Offshore Wind Journal 3rd Quarter 2017

3rd Quarter 2017 www.owjonline.com

Journal

UNMANNED INSPECTORS CAN ENHANCE O&M OPERATIONS IMMIGRATION ISSUE MIGHT DELAY PROJECTS AND INCREASE COSTS WATER-DRIVEN PILING SYSTEM COULD MAKE NOISE MITIGATION UNNECESSARY

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contents

3rd Quarter 2017 volume 6 issue 3

23 8

Regulars 5 COMMENT 47 BEST OF THE WEB

Area reports

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6 A court ruling in the UK could have significant implications for offshore contractors 8 Industry representatives have warned that UK immigration policy could have an adverse effect on the offshore wind industry 9 With costs falling steeply, German industry associations have lobbied the government for more ambitious targets for offshore wind 10 The authorities in The Netherlands have amended tender procedures to take account of the possibility of zero-subsidy bids 12 The nascent offshore wind industry in the US looks set to grow despite President Trump

Decommissioning 14 Designing for decommissioning can help reduce the cost of energy from offshore wind

Floating offshore wind 16 Floating offshore wind energy has come of age, says WindEurope

Foundations 18 Foundations account for a significant part of the cost of an offshore windfarm and jackets rather than monopiles might provide a solution going forward

40

Substations 21 Work carried out by Atkins Ltd and STX suggests that significant reductions in the weight and cost of jack substructures for offshore substations are possible

Survey 22 EDF Energy Renewables’ experience on the Blyth offshore windfarm demonstrates the benefits of conducting a site survey as early as possible 23 Unmanned aerial vehicles and unmanned underwater vehicles both have a role to play offshore

Turbines 24 It has become accepted wisdom in the offshore wind industry that newgeneration, larger turbines will drive down costs, but is that really the case?

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Offshore Wind Journal | 3rd Quarter 2017

contents Cost reduction 26 Giles Hundleby, a director at BVG Associates, analyses how the next CFD auctions in the UK might play out

Innovations 28 The Blue Hammer pile driving system could revolutionise monopile installation

Scour protection 31 Sonars on turbines have a potential role to play monitoring scour

Training 33 Too much attention is focused on the delivery of training, rather than the assessment of competence

Corrosion control 37 Thermally sprayed aluminium could have a big role to play in the offshore wind industry if misconceptions can be overcome

LiDAR 38 LiDAR is continuing to gain ground and is fast becoming established

Turbine support vessels 40 A decision by the German maritime authority has greatly restricted the employment of experienced masters on German windfarms 41 Unmanned aerial vehicles or drones have great potential in the offshore wind industry but teething problems need to be addressed 42 Damen has delivered its first renewables support vessel or ‘RSV’

Installation vessels

3rd Quarter 2017 volume 6 issue 3 Editor: David Foxwell t: +44 1252 717 898 e: david.foxwell@rivieramm.com Commercial Portfolio Manager: Bill Cochrane t: +44 20 8370 1719 e: bill.cochrane@rivieramm.com Head of Sales – Asia: Kym Tan t: +65 9456 3165 e: kym.tan@rivieramm.com Sales, Australasia: Kaara Barbour t: +61 414 436 808 e: kaara.barbour@rivieramm.com Production Manager: Ram Mahbubani t: +44 20 8370 7010 e: ram.mahbubani@rivieramm.com Subscriptions: Sally Church t: +44 20 8370 7018 e: sally.church@rivieramm.com Chairman: John Labdon Managing Director: Steve Labdon Finance Director: Cathy Labdon Operations Director: Graham Harman Head of Content: Edwin Lampert Executive Editor: Paul Gunton Head of Production: Hamish Dickie Business Development Manager: Steve Edwards

44 As turbines grow in size, so new installation vessel concepts will be required

Profile 48 The end of 2017 should see several elements of an advanced test and validation centre for wind energy completed in the Basque region of Spain

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Disclaimer: Although every effort has been made to ensure that the information in this publication is correct, the Author and Publisher accept no liability to any party for any inaccuracies that may occur. Any third party material included with the publication is supplied in good faith and the Publisher accepts no liability in respect of content. All rights reserved. No part of this publication may be reproduced, reprinted or stored in any electronic medium or transmitted in any form or by any means without prior written permission of the copyright owner.

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COMMENT | 5

BATTERY BOOST WILL RANGE FROM WINDFARM TO CONSUMER

B David Foxwell, Editor

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atteries look set to play an incredibly important role in the green energy revolution and could transform the sector in many ways, from generation and storage to use by consumers.

Earlier this month, the UK National Grid’s annual Future Energy Scenarios publication highlighted the fact that a surge in electricity demand is anticipated as a result of the uptake of electric vehicles – demand that should, of course, be met by clean energy sources, including offshore wind and other sources such as onshore wind, wave and tidal energy.

A new generation of batteries could provide energy storage and a source of power in our cars and in our homes, but the incredibly important thing about them is that they have a role to play at every stage of the process of generating and consuming electricity. In the medium term, it’s possible that a new generation of batteries could provide a way to store and manage the electricity generated by offshore wind and other renewables. As OWJ has already reported, Dong Energy plans to integrate a battery system into its Burbo Bank offshore windfarm, creating a firstof-its-kind wind power and battery hybrid system that will provide frequency response to help keep the grid frequency stable at 50Hz and maintain operability. This will be the first time batteries have been integrated into an offshore windfarm.

Deepwater Wind in the US has taken a leaf out of the same book and is bidding a combined offshore wind/battery storage system into a project. It describes its ‘Revolution Wind’ proposal as the largest combined offshore wind and energy storage project in the world.

It is especially good news therefore that the UK government is committed to the development of new battery technology and its integration into the energy market. Late July saw business secretary Greg Clark launch the UK government’s £246 million (US$322 million) Faraday Challenge, which aims to kick-start a process whereby the UK becomes a world leader in battery storage technology. Renewables such as offshore wind

have already become mainstream technology, providing more than 25 per cent of the UK’s electricity and, as RenewableUK put it recently, battery storage is the “missing piece of the puzzle”, which will allow us to maximise the potential of renewable energy resources.

Talking about the Faraday Challenge, Professor Philip Nelson, chief executive of the Engineering and Physical Sciences Research Council (EPSRC), said batteries will form a cornerstone of a low-carbon economy, whether in cars, aircraft, consumer electronics or district or grid storage.

Juliet Davenport, chief executive of renewable energy company Good Energy, described the government’s commitment to battery storage as “a fantastic move” and an exciting moment for the UK’s renewables industry. “Backing innovation in energy storage, as well as more support for offshore wind projects and electric vehicles, will not only attract investment into the UK, create new jobs and increase export opportunities, it will also make sure we have a healthy and greener economy and environment. The move to a 100 per cent renewable future is possible,” she said.

As James Court, head of policy and external affairs at the Renewable Energy Association, noted, the global market is quickly moving towards a decentralised model, relying less on large fossil generation and more on flexible and increasingly renewable sources. More energy storage empowers this and will lead to a lowercost, lower-carbon energy system. The launch of a battery institute, an important part of the Faraday Challenge, will help guide next-generation storage technology through the development process and into use.

However, as Mr Court also noted, for the handbrakes to be taken off battery development, we also need to see rules and regulations made in a different age updated for new technology and approaches, coupled with a renewed commitment to renewables. The government needs to remember that the success of batteries, renewables and smart technologies are all interlinked. OWJ

Offshore Wind Journal | 3rd Quarter 2017

6 | AREA REPORT UK

COMPLYING WITH AN INTERNATIONAL STANDARD

COULD LAND YOU IN STORMY WATERS THE SUPREME COURT’S DECISION IN THE ROBIN RIGG COURT CASE COULD SIGNIFICANTLY AFFECT RISK ASSESSMENT OF EXISTING CONTRACTS, AS WELL AS INSURANCE AND FINANCE ARRANGEMENTS, IN THE OFFSHORE WIND SECTOR AND BEYOND

The court case centred around the failure of foundations on the Robin Rigg offshore windfarm in the Solway Firth

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s Mark de la Haye, a senior associate at Clyde & Co LLP explains, in a decision that may come as a shock to many – and that will have potentially wide-ranging ramifications for English law contracts – the UK Supreme Court has overturned the Court of Appeal’s decision in the long-running Robin Rigg offshore windfarm dispute, by finding in favour of Eon Climate & Renewables (Eon).

In its judgment, the Supreme Court has held that:

• In giving effect to the natural meaning of the words used by the parties, the contractor, MT Højgaard, was under an obligation to ensure that the foundations at Robin Rigg would have a minimum lifetime of 20 years.

• That was the case notwithstanding the fact that the 20-year lifetime provision that Eon relied upon was ‘tucked away’ in a part of the contract that was, according to MT Højgaard, essentially a technical – rather than a legal – document.

Offshore Wind Journal | 3rd Quarter 2017

• This effectively placed on MT Højgaard the consequences of an error in the applicable international design standard – DNV’s J101 – even though MT Højgaard complied with that standard and carried out its work in accordance with good industry practice.

In 2006, Eon employed MT Højgaard to design, fabricate and install 60 wind turbine foundations at the Robin Rigg offshore windfarm in the Solway Firth. In designing the foundations, MT Højgaard’s

designer, Rambøll, relied on J101, the international standard that was commonly used in the industry at the time and was incorporated into the contract.

Unbeknown to the industry then was the fact that J101 contained a fundamental error (the value given in one of the equations for delta was wrong by a factor of about 10) that resulted in a significant overestimation of the axial load capacity for wind turbines with grouted connections.

In 2009, movement was discovered in the grouted

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UK AREA REPORT | 7

connections, following which the error in J101 came to light. All of the foundations required remedial work, at an agreed cost of €26.25M. The contract between Eon and MT Højgaard contained various warranties regarding fitness for purpose and provisions regarding the intended lifetime of the foundations.

The issue before the court was which of the parties should bear responsibility for the error in J101 and, therefore, the cost of the remedial work.

At first instance, MT Højgaard submitted that it had exercised reasonable skill and care and had complied with its contractual obligations to produce a design that was compliant with J101. Eon, on the other hand, submitted that MT Højgaard had warranted that the foundations would have a service life of 20 years, which had not been achieved, and that MT Højgaard was therefore liable as a result.

The judge, Mr Justice Edwards-Stuart, held that the contract required MT Højgaard to provide foundations with a service life of 20 years and, as the foundations did not in fact have a 20 year service life, MT Højgaard was in breach of contract. As such, MT Højgaard was held responsible for the cost of the remedial work.

On appeal to the Court of Appeal it was held that, although there was “much loose wording” contained in “somewhat diffuse contract documents,” on balance MT Højgaard had not given a warranty of 20 years guaranteed service life for the foundations.

Rather, MT Højgaard had agreed to comply with J101, which was intended to lead to offshore structures with a design life of 20 years. MT Højgaard had in fact complied with J101. As such, the

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Court of Appeal allowed MT Højgaard appeal.

Eon subsequently sought permission from the Supreme Court to appeal the Court of Appeal’s decision. The matter was heard by the Supreme Court on 20 June 2017 and judgment was handed down on 3 August 2017.

In reversing the decision of the Court of Appeal and restoring the High Court’s decision, the Supreme Court unanimously allowed Eon’s appeal, and held that MT Højgaard was responsible for the cost of the remedial work to the Robin Rigg foundations.

In reaching its decision, the Supreme Court held that: • The natural meaning of the relevant 20-year clause of the Technical Requirements involved MT Højgaard warranting either (i) that the foundations would have an actual lifetime of 20 years, or (ii) that they would be designed to have a lifetime of 20 years.

• If this clause was an effective term of the contract, then it was breached by MT Højgaard, regardless of whether MT Højgaard warranted an actual 20-year lifetime or a 20 year design life.

• In those circumstances, there were only two arguments open to MT Højgaard as to why this clause should not be given its natural meaning.

• The first argument that was open to MT Højgaard was that such an interpretation would be inconsistent with MT Højgaard obligation to construct the works in accordance with J101.

• In relation to that argument, the court considered a number of earlier cases regarding the reconciliation of competing contractual terms. Applying the principles established in those cases to the present contract, the court found that MT Højgaard’s case faced “an insurmountable difficulty” as J101 and the 20

year lifetime warranty were stated to be the “MINIMUM” requirements to be taken into account by MT Højgaard in the design of the foundations.

• As such, the court held that the “more rigorous or demanding” provision (the 20 year lifetime provision) “must prevail”, as the “less rigorous” provision (that is, J101) “can properly be treated as a minimum requirement.”

• The court went on to comment that MT Højgaard was obliged to determine whether to employ shear keys within the grouted connection.

MT Højgaard chose not to do so, but had shear keys been employed, the court noted that “the problems which arose would, it appears, have been averted.”

• The second argument that was open to MT Højgaard was that the relevant 20 year clause in the contract was simply too slender a thread on which to hang such an important and potentially onerous obligation (that the foundations “would survive for 20 years or would be designed so as to achieve 20 years of lifetime).”

• MT Højgaard relied on a

number of factors in support of this argument. In dealing with and rejecting those factors, the court emphasised the importance of giving effect to the natural meaning of the words used in the contract, irrespective of where those words appear in the contract and/or the nature of document within which they are contained.

• The court was clear that, in this case, the natural meaning of the words used in the contract “appears to impose a duty on MT Højgaard which involves the foundations having a lifetime of 20 years.”

In reaching its decision, the Supreme Court has, it seems, reinforced the more literal approach towards contract interpretation that has been increasingly adopted by the English courts in recent years.

As such, this decision will be of relevance to all parties who contract under English law.

Going forward, contractors in particular should be aware of this decision and the increased risk that it potentially entails. Now, more than ever, the importance of clearly drafted contracts cannot be overstated. OWJ

Mark de la Haye: “Supreme Court’s decision could affect risk assessment, insurance and finance arrangements”

Offshore Wind Journal | 3rd Quarter 2017

8 | AREA REPORT UK

IMMIGRATION ISSUE COULD DELAY PROJECTS AND CAUSE COSTS TO INCREASE CONCERNS HAVE BEEN EXPRESSED THAT CHANGES TO UK IMMIGRATION CONTROLS COULD ADVERSELY AFFECT THE OFFSHORE WIND INDUSTRY AND DRIVE UP COSTS

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ate June saw the International Marine Contractors Association (IMCA) welcome a short-term concession by the Home Office to immigration rules concerning seafarers joining vessels engaged in the construction and maintenance of offshore wind projects.

However, IMCA noted that the recent change by the Home Office of immigration control over such seafarers (to resume after 21 October 2017) is a deviation from decades of common practice and is causing real operational difficulties.

Consequently, IMCA said it would encourage the Home Office to reach out to industry so that its new application of the legal framework relating to seafarers can be introduced in a way that is consistent with the operational needs of industry; without risk of damaging key projects that are critical to delivering renewable energy capacity in the UK. “The success of such projects are schedule, technology, and safety dependent, and a tapered adoption of the new approach to immigration rules would be welcome to give industry certainty and stability in planning future investments,” IMCA said.

The Home Secretary introduced the concession to the immigration rules in June, to allow the employment of non-European Economic Area nationals who are joining vessels engaged in the construction and maintenance of offshore wind projects in UK territorial waters.

However, as highlighted above, the concession will be time limited.

Rob Grimmond: “it is vital that the government talk to industry”

Offshore Wind Journal | 3rd Quarter 2017

“Leave to enter under the terms of the concession will no longer be granted after 21 October 2017,” said the Home Office. “During this period, firms involved in the construction or maintenance of windfarms in territorial waters should look to regularise the position of their workers. British and European Economic Area nationals do not require leave to enter the UK. Those who require leave to enter the UK should have the appropriate permission to do so under the Immigration Rules. In order to qualify for this concession and maintain border security, workers who are seeking leave to enter the UK should produce at point of entry: a valid passport; an ILO108-compliant or ILO185-compliant (having previously ratified ILO108) seamen’s book; and a letter from their employer stating that the worker is employed in the construction or maintenance of a project in territorial waters.

In July, Offshore Marine Management (OMM) said it was calling on the UK government to ensure that the renewables industry leads the conversation on the movement of offshore personnel before making a deal on Brexit. Taking a step forward to ensure a realistic future for renewables in the UK and help to secure a flexible workforce, OMM is encouraging the decision makers in Westminster to learn from the industry and listen to the potential threats and opportunities available.

Calls to facilitate a flexible workforce and to manage industry certification will be on the agenda to ensure that complications within renewables are limited.

Offshore Marine and People Academy (OMPA), a sister company of OMM – which trains and provides personnel for the offshore and marine industries – has backed the need for effective communications to secure a stable, qualified workforce that has the ability to continue to move freely within Europe.

Without this, OMPA claims, due to the increase in paperwork, there will be a reduction of personnel, which will see a bottleneck in the availability of UK workers in EU waters and vice versa. “Any reduction could see daily rates of personnel skyrocket,” said the company.

The call came after the Home Office announced the concession to the immigration rules.

OMM director Rob Grimmond said: “It’s vital that the government talks to the industry to get a real picture of what is at threat for the renewables industry, especially offshore wind and marine energy, if the movement of people is limited. “An increase in certification paired with restricted movement costs time and money to both the UK and the EU economy. Our trained and experienced workers look to be missing out on opportunities because of the potential delays in installation caused by a lack of free moving and qualified workforce who are then unable to provide a full crew to these costly installation vessels.”

Antony Lewis of OMPA said: “We want to secure the future of the offshore workforce moving forward, especially as decisions are made leading up to Brexit. It is important that we engage with the government to ensure the best deal possible for the industry is struck.” OWJ

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Germany AREA REPORT | 9

STEEP FALL IN COSTS SEES INDUSTRY MAKE THE CASE FOR HIGHER TARGETS INDUSTRY ASSOCIATIONS IN GERMANY SAY THEY ARE ENCOURAGED BY THE GROWING NUMBER OF OFFSHORE WIND TURBINES IN THE COUNTRY THAT ARE NOW CONNECTED TO THE GRID, BUT WITH THE COST OF OFFSHORE WIND ENERGY FALLING QUICKLY, THEY WANT THE GERMAN GOVERNMENT TO REVISIT TARGETS AND RAISE THEM

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pril 2017’s startling subsidy-free bids to build what will be the first offshore windfarms anywhere that will be developed without subsidies have raised a host of questions about the role of offshore wind energy in Germany, where existing targets for the roll-out of offshore wind energy set by the federal government look even more unambitious than they did when first announced.

July 2017 saw industry associations with an interest in the offshore wind industry petition the German government to increase the current cap, 15 gigawatts (GW) by 2030, raised to at least 20GW by 2030 and 30GW by 2035. The industry bodies proposing the revised targets include the Working Group for Offshore Wind Energy (AGOW), German wind energy association BWE, the German Offshore Wind Energy Foundation, VDMA Power Systems trade body and the Wind Energy Agency for the northwest region.

The associations say the German government’s expansion targets – set some time before the recent subsidyfree bids were submitted and that call for annual capacity increases of 500–840 megawatts (MW) through the 2020s – would slow the growth of the offshore wind industry in Germany and adversely affect manufacturers and the supply chain and need to be revisited.

“A strong domestic market,

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Raising national targets for the roll-out of offshore wind energy will help drive down costs and help the German supply chain

stable policy framework and significant expansion are necessary if the German offshore wind industry is to maintain its technological leadership and exploit economies of scale to reduce costs,” said the associations.

“The industry, which currently employs 20,000 people, can create new jobs only if German companies continue to participate in the international expansion of offshore wind energy and compete successfully in export markets.”

The industry bodies also say that, in the short term, facilities need to be made available for testing prototypes and innovative technology and regulations need to be modified to support new developments. “Only by investing in research and development and aggressively expanding its market volume can Germany strengthen its position as a technology leader,” they said in a statement issued to OWJ. Grid expansion is another

key element of the successful energy transition, they note. “The success of the energy transition also depends on expansion of the grid system,” the industry bodies wrote. “This means a complete transformation of our entire energy system and the rapid establishment of new grid infrastructure and reduced use of carbon-intensive fossil fuels in the heating and transport sectors.”

The industry bodies are calling for a range of technical approaches to be implemented to upgrade the grid on land and overcome bottlenecks in the grid.

These should include measures to improve network utilisation and greater transparency and the introduction of greater competition for offshore grid connections. Interestingly, at about the same time that the industry associations issued their call for action on grid connection, Samuel Leupold, executive vice president and CEO of wind power at Dong Energy, told the German press that hold-ups in

grid connection are “shaking investor confidence.”

“Companies in the offshore wind industry are eager to take an active role alongside political, economic and community stakeholders in shaping this process, which ultimately affects every member of our society,” the industry associations said, noting that, in the first half of 2017, 108 offshore wind turbines with a combined capacity of 626MW fed power into Germany’s national grid for the first time, and as of 30 June 2017, a total of 1,055 offshore wind turbines with a total capacity of 4,749MW were connected to the grid – figures that the industry associations described as “encouraging.”

The industry expects a total increase of approximately 900MW for 2017 as a whole.

In the first half of 2017, offshore wind energy produced 8,480GWh of electricity, which equates to approximately 70 per cent of last year’s total output. OWJ

Offshore Wind Journal | 3rd Quarter 2017

10 | AREA REPORT The Netherlands

German tenders prompt Dutch to seek subsidy-free bids

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he Netherlands minister of economic affairs Henk Kamp says he is seeking subsidyfree bids for both zones in the upcoming tender process for the Hollandse Kust offshore windfarm.

In a letter to the House of Representatives on 28 June 2017, the minister said companies prepared to make zero-subsidy bids would be given the opportunity to bid for the projects first.

“In this tender, market parties may submit a bid for the realisation of the windfarm without subsidies. In the event that this tender procedure fails to yield an acceptable bid, a tender procedure that includes subsidies will be started,” said the minister.

In the tender without subsidies, bids will be evaluated based on criteria established in the Offshore Wind Energy Act. These include the knowledge and experience of the parties involved, quality of the design of the windfarm, the capacity of the windfarm, social costs, the quality of the identification and analysis of the risks involved, and the quality of the measures initiated to safeguard cost-effectiveness.

The Ministry of Economic Affairs said

In the light of recent zerosubsidy bids in Germany, the Dutch Government has opted for a pragmatic solution for its next round of tenders for offshore windfarms

it plans to elaborate on the above criteria in a new Ministerial Order for Offshore Wind Energy.

“For this tender, the deciding factor will no longer be the lowest price, but rather the quality of the bidding party, the quality of the design and the quantity of electricity that will be produced,” it said.

In the event that the subsidy-free procedure fails to provide an acceptable bid, a tender that includes subsidies will be opened, and bids will be ranked based on the bid price.

The decision to seek subsidy-free bids follows three tenders for offshore windfarms in Germany that resulted in a subsidy-free award: the He Dreiht windfarm (EnBW), the OWP West windfarm

(Dong Energy) and the Borkum Riffgrund WII windfarm (Dong Energy).

Martin In De Breakt, a partner at law firm Stibbe in Amsterdam, said the minister acknowledges that there are differences between the recent German and Dutch tenders, including (among other things) the regulatory framework, the expected date of operation and the wind speed. However, despite these differences, Mr Kamp did not want to exclude the possibility that a nonsubsidised bid would be submitted in the tender for Hollandse Kust I and II. The Offshore Wind Energy Act in the Netherlands already provides for a procedure for tenders including subsidies and one for non-subsidised tenders. In a tender procedure including subsidies, the applicant with the lowest subsidy price wins the tender.

The Hollandse Kust (Zuid) Wind Farm Zone (HKZWFZ) lies to the west of the Netherlands, offshore the province of ZuidHolland (South Holland). This windfarm zone has four sites. The tender round for HKZWFZ will offer two 350 megawatt projects for development: one at site I and the other at site II. The opening of the tender is expected this autumn. OWJ

To-date, Dutch offshore windfarms have all been subsidised but cost reduction means that zero-subsidy bids might now be possible

Offshore Wind Journal | 3rd Quarter 2017

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OFFSHORE

JACK OF ALL TRADES W I T H D G J A C K V E R S AT I L I T Y C O M E S A S S TA N D A R D .

E Q U A L LY AT H O M E I N T H E R E N E W A B L E S A N D NON-RENEWABLES SECTORS, DG JACK COMBINES DESIGN AND CONSTRUCTION EXPERTISE TO FULFILL A WIDE R A N G E O F A C T I V I T I E S O F F S H O R E . S PA N N I N G E V E R Y T H I N G F R O M R E PA I R A N D M A I N T E N A N C E T O A C C O M M O D AT I O N , W H AT E V E R Y O U R N E E D S , D G J A C K ’ S G O T I T C O V E R E D .

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12 | AREA REPORT US

TRUMP PRESIDENCY FAILS TO DAMPEN

US OFFSHORE WIND PROSPECTS ALTHOUGH INITIAL ESTIMATES PROVED TO BE A LITTLE OVERBLOWN, THE LATEST ANALYSES OF THE POTENTIAL SCALE OF OFFSHORE WIND PROJECTS IN THE US PAINT AN ENCOURAGING PICTURE FOR THE SECTOR OVER THE NEXT DECADE

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mong the latest reports looking at the potential for offshore wind in the US, Westwood Global Energy Group’s (WGEG’s) ‘World Offshore Wind Market Forecast 2017-2026’ suggests that cumulative capacity is set to grow from 30 megawatts (MW) in 2016 to 2.5 gigawatts (GW) by 2026, with an additional 1GW of capacity from projects that have not yet passed conceptual phases, assuming an offshore wind target of 5GW by 2030.

US offshore wind expenditure is forecast to total US$28 billion between 2017 and 2026, with a 39 per cent year-onyear growth. Hardware capex is expected to amount to €19.1bn, accounting for 68 per cent of total spend, followed by

Westwood Global Energy Group forecasts that cumulative US capacity is set to grow to 2.5 gigawatts by 2026

Offshore Wind Journal | 3rd Quarter 2017

installation at €6.2 billion (22 per cent) and planning and development at €2.9 billion (10 per cent). The US total population of operational turbines is expected to grow from six in 2016 to 580 by 2026.

Since the first offshore windfarm in the US was completed last year, Deepwater Wind has obtained permission to build the 90MW Deepwater One windfarm off New York. Statoil will be exploring the potential to host over 1GW offshore New York. Other encouraging signs include the first US auction under President Trump, which resulted in a winning bid of nearly US$9.1m from Avangrid Renewables for the 1.5GW Kitty Hawk project lease, and the award of offshore wind renewable credits by the Maryland Public Service Commission in May 2017.

“Despite President Trump’s pro-oil and gas stance and his decision to leave the Paris Climate Accord, there are positive signs that US offshore wind is gaining momentum,” said WGEG analyst Marina Ivanova. “More importantly, as each state has its own renewable electricity mandates, the withdrawal from the Paris Climate Accord is likely to affect emission targets at a federal level only. It remains to be seen the extent to which President Trump will be able to influence individual states’ renewable policies,” she explained.

Recent weeks have seen the announcement of details of a survey that is to be conducted by the National Renewable Energy Laboratory in the US. The survey will determine if the Gulf of Mexico can transform 50 years of offshore oil and gas expertise into a thriving offshore renewables industry. Funded by the Bureau of Ocean Energy Management, the project will examine the feasibility of various potential offshore energy resources in the Gulf of Mexico.

The Department of Energy’s ‘Wind Vision’ Report aimed to install 86GW of offshore wind by 2050 (a target that now seems wildly optimistic), with the Gulf Coast playing a large role. States in the region – including Florida, Texas, and Louisiana – will contribute 10 per cent,

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US AREA REPORT | 13

or 8.6GW, of offshore wind energy to help achieve the goals set out in the Wind Vision report.

The Gulf offers a number of advantages for offshore wind, including shallow water that makes turbine installation easier, warm waters, accessibility and close proximity to existing offshore oil and gas infrastructure.

But the region’s lower wind speeds present a challenge, and hurricane-resistant turbine designs and survival strategies may be required to reduce the increased risk posed by environmental factors.

The levelised cost of energy for Gulf Coast offshore wind will be determined using the geospatial offshore wind cost model developed by the National Renewable Energy Laboratory (NREL).

NREL scientists Suzanne Tegen and Walt Musial will use the model, which assesses variables like water depth, wind resource, and distance to port.

Current scenarios show that the levelised cost of energy may fall below US$100 per megawatt hour by 2025 at some sites in the Gulf.

Researchers will also undertake a sitespecific economic analysis to determine which offshore wind locations offer the most promise for developers. A job impact analysis, performed using NREL’s jobs and economic development impact model, will estimate the economic impact of construction and turbine operations.

In July the Carbon Trust said it had successfully completed a project supporting offshore wind development in the US. Building on experience gained over a decade working in the European market, the Carbon Trust has generated guidance for the New York State Energy Research and Development Authority (NYSERDA) on how to deploy cost-effective wind resource measurement technology to generate bankable data to improve project financing of future offshore wind developments. The Metocean Plan aims to support developers and financiers with the deployment of floating light detection and ranging (LiDAR) solutions, a proven technology (see elsewhere in this issue) that delivers cost savings of up to 90 per cent compared with traditional fixed met masts.

Offshore wind development in New York has a lot of potential. In the 2017 State of the State, Governor Andrew Cuomo made an unprecedented commitment: to develop up to 2.4 gigawatts of offshore wind by 2030, enough to power 1.25 million homes. NYSERDA is the lead agency co-ordinating offshore wind development

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In the US, each state has its own renewable electricity mandate and President Trump can do relatively little to influence their policies

on behalf of New York State, which will support the ambitious Clean Energy Standard to meet 50 per cent of New York’s electricity needs with renewable sources by 2030. In support of the governor’s proposal, NYSERDA continues to work closely with coastal communities and the fishing and maritime industries to identify offshore wind sites to be included in New York State’s offshore wind master plan.

Recommendations detailed in the plan cover all aspects of deployment including project management set up, and operations and maintenance of the devices themselves.

Site-specific elements such as New York permitting requirements and the current lack of offshore met masts to validate a floating LiDAR in New York waters are also considered. The plan draws on recent publications from the OWA, including the OWA Floating LiDAR Recommended Practice. NYSERDA sought feedback on the plan to ensure that the final plan reflected views of wider stakeholders.

In another important development, Zentech Inc and Renewables Resources International have announced their intention to build the first Jones Actcompliant turbine installation vessel for the US offshore wind industry. The four-legged, self-propelled, dynamically positioned class 2 jack-up would be based on a US-built barge. Zentech plans to install four truss legs with spud cans on a newly built hull.

Business Network for Offshore Wind executive director Liz Burdock said the vessel would provide the evolving US offshore

wind industry with a much needed, costcompetitive installation asset. She said the vessel could also work in the offshore oil and gas industry, undertaking decommissioning in up to 300ft (90m) of water.

“The Jones Act vessel is designed to navigate the New Bedford Hurricane Barrier and will carry and install in this configuration components for at least three complete 6-9 megawatt wind turbines,” Ms Burdock said.

The vessel’s jacking system will be rated at 16,000 tons. Up to four 8MW, fully assembled wind turbines could be installed using a patented cantilever package,” she said.

Renewable Resources International managing partner Andy Geissbuehler said that “With larger scale offshore wind projects following Block Island, the US market requires marine logistics, such as Zentech’s competitive, Jones Act compliant jack-up installation vessel.”

Dong Energy North America president Thomas Brostrøm said “The deployment of a US-flagged vessel is a positive sign and a step in the right direction for the offshore wind industry in the US. This will help in the creation of a sustainable supply chain that includes several suppliers. We welcome initiatives such as this from serious market players in the industry.”

Ms Burdock added that “Discussions with US shipyards in the Gulf and East Coast predict delivery no later than the fourth quarter of 2018.” She noted that the unit will be constructed utilising US-built components such as the barge, legs, spud cans and propulsion. OWJ

Offshore Wind Journal | 3rd Quarter 2017

14 | DECOMMISSIONING

Understanding decommissioning now

can help reduce the cost of energy In the offshore oil and gas industry, decommissioning is in focus as massive structures such as Shell’s Brent topsides begin to be brought ashore – a similar level of focus in the offshore wind industry could help reduce the cost of energy

The offshore wind industry can benefit from experience in the oil and gas sector, despite the differences between the two

Offshore Wind Journal | 3rd Quarter 2017

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s noted recently in our sister publication Offshore Support Journal, the cost of decommissioning oil and gas infrastructure is a major issue. In the offshore oil and gas industry, greater co-operation to share good practice, lessons learned and decommissioning campaign management is needed to bring costs down. Cost reductions of around 35 per cent are being targeted. Operators need to look for synergies with other energy industries, it is said, and new technology and different working practices will be required to make the most expensive parts of decommissioning less expensive.

The offshore wind industry won’t have to deal with some of the high cost aspects of decommissioning an oil field – such as plugging and abandoning infrastructure in which hydrocarbons are involved – but as a number of poster presentations at Offshore Wind Energy 2017 Conference highlighted, the industry needs to begin to focus on decommissioning now if costs aren’t to escalate later.

As experts from DNV GL told the conference, from the early stages of designing marine structures, decommissioning should be considered in order to minimise the impact on lifetime costs. Prudent consideration of end-of-life costs during the design and operation phases and the efficient execution of the decommissioning phase when it comes can reduce the cost of energy, and liability can be reduced. Similarly, owners of existing offshore windfarms need to make cost-efficient decisions regarding life extension, late-life operation and ultimately decommissioning and removal.

If you think that decommissioning isn’t an issue for the offshore wind industry yet, think again. A handful of projects have been dismantled in the last two years (such as Yttre Stengrund, Lely and elements of others), and others are approaching the end of their design lives.

As DNV GL pointed out, decommissioning in the offshore oil and gas sector began more than 30 years ago, and a large body of experience and specialised techniques has been developed and continues to evolve. With care, the offshore wind sector can benefit greatly from this extensive experience whilst keeping aware of distinct differences between the two sectors.

At a high level, the main similarities with offshore oil and gas structures are the range of foundation types (jackets, piles, gravity base, suction buckets) and the site conditions. Much knowledge is transferable, says DNV GL, but there are significant differences between the two sectors arising primarily from the much greater risks of pollution and environmental impact with oil and gas installations, requiring much greater consideration during dismantling and removal, and also from the scale and numbers, whereby windfarms comprise multiple installations that are essentially identical compared with the single complex entity at an oil installation.

The oil and gas industry has also made advances in subsea cutting technologies, in remotely operated subsea vehicles and in heavy-lift vessels to serve the needs of decommissioning.

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DECOMMISSIONING | 15

Developments needed for offshore wind include cutting techniques for the largest monopiles, and alternative techniques such as vibroremoval may be embraced if complete foundation removal is desired.

“In terms of planning ahead, ease of decommissioning should be built into the design, such as breaking down large structures into modules or releasable joints,” says DNV GL. “Throughout the lifetime, structural changes need to be recorded in detail. The marine logistics during decommissioning need careful optimisation as costs are particularly sensitive to the use of expensive specialised vessels.

“Without considering decommissioning at all stages in the life of an offshore wind project, the overall cost of energy may be higher than necessary. The offshore oil and gas industry has learned pertinent lessons in the need to plan years ahead before cessation of production and preferably at the design stage. It has developed techniques and methodologies in certain key areas. For offshore wind, these methods need to be supplemented by enhanced and new techniques. Optimisation of marine operations is essential, for example, taking advantage of the programme nature and scale, working with multiple vessels and recognising their major contribution to the overall costs.”

Experts at NIRAS in Denmark say they agree that there is a need in the offshore wind energy industry to gain a greater understanding of decommissioning. “Planning for decommissioning can reduce the cost of energy,” said Johan Finsteen Gjoedvad and Morten Dallov Ibsen from NIRAS in a poster presentation at Offshore Wind Energy 2017. “It is important to address it as early as possible, even during the de-risking or design phase.” They note that other industries – such as offshore oil and gas – have failed to seriously assess the cost of decommissioning “and have been surprised with the actual cost.”

In 2014, NIRAS initiated the ODIN-WIND project, the aim of which is to develop a model and management tool for the decommissioning process. The project also includes tools for estimating the remaining lifetime of an offshore windfarm and provides a best-practice guide for decommissioning windfarms.

The project is being undertaken in collaboration with the Danish Energy Agency, Maersk Broker, Vattenfall, Dong Energy, DTU Energy and TWI. It was due to be completed in mid-2017.

“ODIN-WIND has made it possible for NIRAS to assist clients on offshore wind projects in regards to decommissioning,” the authors of the presentation explained, “including projects’ initial feasibility, due diligence and evaluating windfarms for decommissioning.”

The ODIN-WIND tool assesses decommissioning requirements through a detailed analysis of actual methods, logistics, environmental issues, legislation and weather models. Cost estimates of capex are produced. This is in contrast to the more conventional viewpoint of reverse engineering and assessment of cost as a multiple of installation costs.

The ODIN-WIND approach has been applied in the different phases during which decommissioning can be addressed: feasibility, design phase, due diligence and actual decommissioning. Relevant techniques and data have been collected from partners and experts.

The tool supports the development of a decommissioning strategy, which is used for decommissioning by design during the design phase. The decommissioning strategy is updated continuously through the lifespan of an offshore windfarm, including commissioning and O&M. NIRAS says the ODIN-WIND approach has proved to be more accurate than conventional approaches to decommissioning. “The detailed and accurate estimates that ODIN-WIND provides are due to the fact that economic contingencies are replaced with actual costs based on actual methods,” said NIRAS, noting that it can also help reduce costs and the cost of energy because the owner of a windfarm can allocate funds for decommissioning that are accurate. It says the cost of energy is further reduced because ODIN-WIND enables interaction between designers of offshore wind structures and entities that are active in the O&M phase.

“The benefit of addressing decommissioning early in the design phase is clear and is directly linked to reducing the cost of decommissioning,” NIRAS concluded. “Optimisation of decommissioning assists in reducing environmental impact, reduces the use of resources and promotes a circular economy.

ODIN-WIND can guide asset owners through the different phases of a project and provide input to end-of-life estimation and re-powering considerations and provide the basis for an environmental impact assessment.”

Experience with met masts proves the point Another poster presentation at Offshore Wind Energy 2017 Conference from Emilie Reeve, Dan Kyle-Spearman and Jan Matthiesen at the Carbon Trust noted that more and more met masts and earlyinstalled windfarms are being decommissioned at extremely high costs.

The Carbon Trust has undertaken a study reviewing the costs, barriers and opportunities of decommissioning. The conclusion was that the supply

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chain is not prepared for offshore wind decommissioning and there is no fit-for-purpose technology so the costs are extremely high.

It noted that decommissioning activities will continue to increase in the next 10–15 years, and there is an opportunity to develop the appropriate tools and methodologies to support future large-scale decommissioning activities.

However, this needs to be started now in order to ensure

the tools are sufficiently developed and tested.

A study undertaken by the Carbon Trust demonstrated that the industry will start seeing larger-scale decommissioning within the next 10–15 years. At present, it’s expected that the costs of decommissioning would be equivalent to approximately 65–70 per cent of installation costs, which is excessive.

Through discussions with developers and industry, the Carbon Trust has identified the

opportunity for innovation to considerably decrease the cost of decommissioning, largely by reducing the dependency on a costly heavy-lift vessel.

However, these innovations will need to be developed, trialled and tested in advance of the large-scale decommissioning activity in order to achieve the necessary cost reduction.

“Decommissioning needs to be considered now, in order to ensure the industry doesn’t pay excessive costs later,” said the Carbon Trust. OWJ

Offshore Wind Journal | 3rd Quarter 2017

16 | FLOATING OFFSHORE WIND

FLOATING OFFSHORE WIND COMES OF AGE

AS HYWIND SCOTLAND TAKES SHAPE The turbine for one of the Hywind floaters is lifted into place

FLOATING OFFSHORE WIND IS NO LONGER CONSIGNED TO THE LABORATORY – IT’S READY TO BE ROLLED OUT ON AN INDUSTRIAL SCALE

Offshore Wind Journal | 3rd Quarter 2017

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ccording to the latest report from WindEurope, not only has the technology for floating offshore wind reached maturity, costs are also predicted to plummet in the coming years. One of the key advantages of floating offshore wind is that turbines are located further away from shores in areas with higher average wind speeds without depth constraints.

Turbines can be significantly larger on floating installations, and construction, installation, operation and maintenance costs could be lower than on fixed sites.

Capacity can thus be improved leading to an increased generation of electricity, allowing for cost reductions of 10 per cent by 2020 and 25 per cent by 2030.

Ivan Pineda, WindEurope’s director for public affairs, said “Floating offshore wind is no longer an R&D exercise. The technology has developed rapidly in recent years, and it is now ready to be fully commercialised at utility scale projects.

Adding this option to the market means more offshore wind in total, and it’s this extra capacity that we will need to meet the 2030 goals.”

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FLOATING OFFSHORE WIND | 17

Floating offshore wind offers a vast potential for growth – 80 per cent of all the offshore wind resource is in waters 60m and deeper in European seas, where traditional bottom-fixed offshore is less attractive. At 4,000 gigawatts, it is significantly more than the resource potential of the US and Japan combined.

WindEurope says tapping into this inexhaustible resource will be key to expanding the overall capacity of offshore wind and supporting the EU in reaching the target of 27 per cent of energy by renewables by 2030. As highlighted in WindEurope’s latest report, Unleashing Europe’s offshore wind potential, offshore as a whole could in theory generate between 2,600TWh and 6,000TWh per year at a competitive cost – €65/MWh or below, representing 80–180 per cent of the EU’s total electricity demand.

Among the floating offshore wind projects in Europe are: Hywind Scotland, a 30 megawatt (MW) project in Scotland expected to be commissioned in 2017; Kincardine, 48MW, Scotland, from 2018; Dounreay Tri, 2 x 5MW, Scotland, 2018; WindFloat Atlantic, 30MW, Portugal 2018/9; French pre-commercial windfarms 4 x 25MW, 2020; Atlantis/Ideol, 100MW, UK, 2021; Gaelectic, 30MW, Ireland, 2021.

Late July 2017 saw the first Hywind Scotland floating wind turbine arrive in Scottish waters, the turbine having been installed on the floating foundation in Norway and then towed to the UK. By the end of July, all of the Siemens Gamesa 6MW turbines that will make up the Hywind project had been installed on their foundations. The floaters, which use a spar-type substructure, are being towed from Stord on the west coast of Norway to Scottish waters where they will be installed 25km off the coast of Peterhead in Aberdeenshire in water depths ranging from 90m to 120m.

“Siemens Gamesa views the floating windfarm market area the same way as we did with offshore windfarms in the early beginning: it is a very interesting area that is initially a niche market. This niche may, however, develop over time into a large market. It is a niche in which we would like to build a strong position,” said Michael Hannibal, chief executive, offshore at Siemens Gamesa Renewable Energy.

The Hywind concept has already proven its effectiveness back in 2009, when Statoil and Siemens Wind Power installed a 2.3MW turbine for the first full-scale floating wind turbine project,

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the Hywind Demo.

Apart from the above-mentioned, there are a growing number of research, development and demonstration projects underway in Europe.

LOC Group has been selected to head a consortium of companies in a Carbon Trust-led floating offshore wind joint industry project (JIP) to investigate the infrastructure and logistics challenges faced in utility-scale projects.

The investigation report and recommendations, which has been commissioned by the Carbon Trust and JIP partners Dong Energy, Engie, Eolfi, E.ON, Innogy, Kyuden Mirai Energy, Statoil and Vattenfall, will help drive the commercialisation of floating wind technology. The consortium includes Portuguese offshore renewables consultancy WavEC and offshore geoscience and geotechnical engineering consultancy, Cathie Associates.

DNV GL updating design standard for floating wind turbine structures DNV GL says it expects to publish a revised and updated version of its standard for floating wind turbine structures later this year. It first issued DNV-OS-J103 Design of Floating Wind Turbine Structures in June 2013. The standard was based on a joint industry effort with representatives from manufacturers, developers, utility companies and certifying bodies.

It now plans to publish a revised version of DNV-OS-J103 as part of the harmonisation of the DNV GL codes for the wind turbine industry following the merger between DNV and Germanischer Lloyd in 2013.

The updated standard will reflect experience gained after the first issue was published in 2013 as well as the current trends in the industry.

Building on its members’ extensive experience in the offshore wind industry, and drawing on new technical information and knowledge, the consortium will outline key solutions for the realisation of floating offshore windfarms with a capacity of 500MW. The report will first categorise all floating wind platform solutions currently being trialled by industry to provide recommendations for overcoming foreseeable challenges in the construction of 500MW windfarms, regardless of the type of floating technology being used.

LOC’s report will outline the essential logistics needed for the assembly, storage and construction of floating offshore wind platforms and, in particular, cover the details of dockside construction, marine transportation and installation operations.

Bureau Veritas has issued a preliminary design approval for a floating offshore wind turbine foundation designed by DCNS Energies. The floating foundation is based on a semi-submersible and was designed to be competitive, adapted to mass production, easily towable, connectable and disconnectable, and adaptable to site conditions and local industrial environments.

Approval was provided as part of the General Electric and DCNS Energies Sea Reed project, a floating offshore wind turbine development initiative supported

by ADEME, the French Environment and Energy Management Agency.

Matthieu de Tugny, chief operating officer, senior vice president and head of offshore at Bureau Veritas, said “We are seeing increasing interest in floating offshore wind technology as demand for wind power increases. Foundations fabricated onshore can be installed in deep water. Because of their low environmental impact during installation and application in deeper waters, we can see that demand for floating offshore wind will grow.”

Preliminary design approval implies that the basis of design has been approved.

The design is feasible and achievable and contains no technological issues that may prevent the design from being matured.

Co-operation between Bureau Veritas and DCNS Energies will continue to grow with a floating wind project planned to be deployed between the Groix and Belle-Île Islands. The array will consist of four 6MW GE Haliade turbines installed on a hybrid (steel and concrete) version of DCNS Energies’ floating foundation. OWJ

Offshore Wind Journal | 3rd Quarter 2017

18 | FOUNDATIONS

EVER-LARGER TURBINES PUT JACKET FOUNDATIONS IN THE FRAME Foundations account for a significant part of the cost of an offshore windfarm – making them more cost-effective can help meet ever-lower cost targets, and jackets rather than monopiles might provide the solution

Monopiles such as the one shown here have predominated to date but jackets have plenty of potential

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oundations can account for 30–50 per cent of the total cost of development of an offshore windfarm, so their design, construction and installation is an incredibly important area on which the industry needs to focus in order to continue to reduce the levelised cost of energy from offshore wind.

Continuous improvement and a fair amount of innovation will be required in a number of areas, not least because the size of turbines is growing all the time.

8–9 megawatt (MW) turbines are being offered by OEMs now, and 12MW – even 15–20MW units in the longer term – are on the drawing board.

However, as experts at Atkins in the UK told the Offshore Wind Energy 2017 Conference in London in June, foundations capable of supporting 10–20MW turbines are perfectly feasible.

Atkins has been reviewing foundation design, looking at potential future trends between now and 2025, including fixed and floating structures. It notes that foundation

Offshore Wind Journal | 3rd Quarter 2017

design will need to evolve quickly to meet the demands that new, larger, more powerful turbines will place on them.

Atkins believes that monopile foundations will continue to predominate in shallow water (0–40m), but the shift to larger turbines of 8+MW will favour the use of jacket foundations. The use of gravity base foundations is also gaining momentum for offshore windfarms with challenging ground conditions, and the use of floating structures is a great option for water depths exceeding 60m.

The results of the work that Atkins did are reassuring in as much as the company believes that reducing jacket weight by up to 10–15 per cent is possible. This was done by reviewing the requirements for installation, fabrication and design parameters such as corrosion allowance and local jacket joint design.

Having carried out extensive market research on foundations, Atkins believes it has identified a number of design drivers that can help reduce costs. It

believes it has also identified cost-saving opportunities for standardisation – a view shared by ST3 Offshore in Poland, which believes that, although jackets are relative newcomers in the offshore wind space, there is significant potential for design optimisation. It also believes that jackets can be an attractive alternative to the monopile cost wise.

Working closely with Salzgitter and a number of major developers, ST3 Offshore has developed a standardised jacket foundation that it anticipates is adaptable to the majority of seabed types, water depths and turbines.

Norman Skillen, managing director of ST3 Offshore UK Ltd, noted that, with the downward forces on a foundation increasing with turbine size, these forces must be distributed through the foundation.

“For large turbines and expected turbine development, jacket foundations present a technical and commercial alternative to building larger monopiles,” he told delegates.

He explained that ST3 Offshore’s standardised jacket foundation is built using prefabricated nodes, standard pipes and serial production techniques. The prefabricated nodes are prepared using robotic welding and automated manipulation as part of the series production process.

“ST3 Offshore has developed the design of a number of standardised jackets and found that they offer developers a real alternative in terms of a significant reduction in the levelised cost of energy and weight reduction. The jacket solution is also a more environmentally friendly solution, particularly when considered within the lifecycle cost of offshore windfarms,” Mr Skillen said.

Jesper Møller, head of offshore concepts and solutions, told the Offshore Wind Energy 2017 Conference that, prior to the formation of Siemens Gamesa, Siemens

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FOUNDATIONS | 19

Wind Power had been working on a gravity jacket concept since 2012.

“The governing thought in designing the jacket was to make it as simple as possible,” said Mr Møller. “From sourcing to assembling to installation, why use customised material if standard pieces will do? Why design a foundation that requires special installation equipment? Getting a high number of players involved around a jacket foundation can ensure that the design is optimised to manufacturing, transportation and installation.”

Mr Møller said internal and external projects that Siemens Gamesa has been running the last few years had provided valuable lessons on where the company and the industry as a whole needs to focus in order to achieve the desired cost levels.

“In addition, current standards for jacket construction are conservative and leave room for improvement,” he explained.

“One way to achieve this is robot-welded nodes, which make it possible to reduce the likelihood of mistakes and enable more accurate, smoother welding.”

Mr Møller noted that jackettype foundations have been used in the offshore industry before, as have standardised components, but have not yet been used in the offshore wind industry.

However, Siemens is currently involved in a number of projects with partners to define new manufacturing standards for robot-welded nodes.

Among upcoming projects is one recently awarded by Innovation Fund Denmark that will bring together a developer, academia, welding firms and a manufacturer of foundations.

Mr Møller said that conceptual design of standardised jackets demonstrates that cost savings of up to 40 per cent are realistic. “Working together along the value chain has provided valuable insights and benefits in design for manufacturing and transportation,” he said. “Fatigue tests of nodes have shown that robot-welded nodes are feasible, and the feedback from DNV GL has been very positive.

“Using standard components from an existing supply chain and ensuring flexible manufacturing, transportation and installation are crucial to ensure longterm cost reductions,” Mr Møller said.

“Modularisation of jacket structures is important in order to avoid large upfront investment, which significantly reduces bankability. Modularisation can provide the necessary flexibility to deal with fluctuating market situations. In finding

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fast and effective assembly methods, a bolted jacket solution is one of the major contributors as it will work in and around the splash zone. Siemens Gamesa will work on this and potential other solutions,” Mr Møller concluded.

Representatives of ODE in the UK told delegates that, to date, most solutions for deeper water had focused on floating technology, but ODE believes that another type of fixed foundation, the articulated wind column (AWC), has much to recommend it.

They described the AWC as a ‘crossover’ technology with 40 years of use in the offshore oil and gas industry that ODE had re-engineered for mid- to deepwater environments (50–200m). “Designed to accept turbines of 8MW and above, field demonstration sites are now being sought with a 6–8MW deployment in the range of 90–100m water depth,” they explained, noting that the AWC provided a cost-effective solution combined with ease and flexibility of construction, ease of installation and removal and the ability to

support very large turbines. Constructed from steel or concrete, the AWC has an articulated joint at the foundation’s base that enables it to be a robust, stable and durable solution for larger turbines in deep water.

“Engineering and model testing demonstrated that the AWC is economically and technically feasible for deepwater, large turbine applications when modelled with an 8MW turbine in 90m of water,” they told delegates.

“Modelling demonstrated a tilt of more than 6 degrees occurred 0.002 per cent of the time, well within parameters set by the turbine supplier.

Looking for a demonstration site, it was found that the AWC increases the UK offshore wind market size,” they claimed, “and opens much of the north, west and southwest to offshore wind, which would be of particular relevance to Scotland, where only around 1 gigawatt of offshore power is accessible by conventional technology but deepwater technology would open up over 60GW of potential.”

UPDATED STANDARD TO BE PUBLISHED Representatives of the University of Massachusetts, DNV GL and Dong Energy have described the development of an updated standard for bottom-fixed foundations. They explained that the International Electrotechnical Commission (IEC) standard for bottom-fixed offshore wind turbine design (IEC 61400-3) has been significantly updated to reflect advances in offshore wind turbine technology since the standard was first published in 2009. To increase international applicability of the standard, more guidance was provided on ice loading of wind turbine structures and new guidance added on the prediction of tropical cyclone loading. Additionally, a number of changes were made to the standard to align it more closely to the latest updates to the IEC standard for onshore wind turbine design 61400-1.

A review of the standard was carried out by a team of 40 international experts from industry, academia and certification bodies. Ten meetings of the maintenance team were held over a period of four years, at which the requirements of the standard were discussed, the work of subgroups was presented and updates to the final text of the standard were agreed.

The starting point for the work of the maintenance team was a set of recommendations from IEC TC88 national committees following review of edition 1 of the IEC 61400-1 standard.

Members of the maintenance team added their own experience of using the first edition of the standard and suggestions for improvement. A committee draft for voting was circulated to national committees earlier in 2017.

Significant updates include simplifications to the design load case specifications to make the standard simpler to apply, a greater focus on the assessment of site-specific environmental conditions, additional guidance on ice loading of offshore wind turbines and their support structures and new guidance on extreme loads that result from tropical cyclone events. The standard has also been aligned with the latest updates to IEC 61400-1.

“Edition 2 of IEC 61400-3 contains significant updates that embody the latest best practices of the offshore wind industry and make the standard easier to apply,” they explained, noting that edition 2 of IEC 61400-3 will be reviewed by national committees later in 2017 and is expected to be published later this year. A separate technical specification for the design of floating offshore wind turbines is also expected to be issued in 2017. OWJ

Offshore Wind Journal | 3rd Quarter 2017

Foto: Kristina Becker

THE BIGGER DIFFERENCE Foundations by EEW SPC EEW Special Pipe Constructions GmbH info@eewspc.de, www.eew-group.com

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SUBSTATIONS | 21

IMPROVED DESIGN

CAN MAKE NEW-GENERATION SUBSTATIONS MORE COST-EFFECTIVE WORK CARRIED OUT BY ATKINS LTD IN THE UK AND STX IN FRANCE SUGGESTS THAT SIGNIFICANT REDUCTIONS IN THE WEIGHT AND COST OF JACKET SUBSTRUCTURES FOR OFFSHORE SUBSTATION ARE POSSIBLE AND THAT ‘SCALABLE’ OFFSHORE PLATFORMS CAN ALSO HELP REDUCE COSTS

D

escribing an analysis of substructures for offshore substations carried out at Atkins at the Offshore Wind Energy 2017 Exhibition and Conference in London in June, representatives of the company said their review of current design practice and recent design experience suggested that savings of up to 15 per cent in weight of jacket substructures could be achieved in future.

“This saving resulted from reviews of the requirements for cable pulling, corrosion allowance and the methodology for local jacket joint design,” they explained.

“However, further future weight savings are also considered possible, both for AC and HVDC platforms.”

The design of offshore substations substructures needs to fulfil whole life cycle requirements by considering all phases of design, including fabrication, installation, operation and decommissioning.

Projects in the offshore wind industry are moving further from shore into deeper waters, which will lead to an inevitable cost increase due to more complex fabrication and installation, making potential cost reductions even more important.

“To offset the costs involved in developing such challenging projects, there is a clear need to reduce the cost of substructures through

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Atkins believes that substructures for substations can be made more cost-effective to build and maintain

improved reliability, structural efficiency and challenging the norms,” said Atkins, noting that a holistic approach, taking account of fabrication, installation, operation and decommissioning requirements is essential for successful delivery of a design.

Standardisation also has an important role to play.

The company has carried out extensive market research on the AC and HVDC markets.

This identified historic trends in substation design around the world, observing key design drivers and characteristics and based on Atkins’ extensive experience in the substation substructure design, in-depth in-house knowledge has been used for the prediction of future trends.

Since there is potential synergy between offshore wind turbine substructure and substation substructure,

Atkins undertook a comparison between the two types of substructures, and the key differences between both structures have been identified and listed. This was supplemented by carrying out an in-depth review of DNV GL-ST-0126 (Support structures for wind turbines) and DNV GLST-0145 (Offshore substations).

Having completed its analysis of substructures, Atkins believes that, although the drivers of design decisions for offshore substations can be quite different from those for wind turbines, to achieve efficient (or lighter) design, it is important for the industry to challenge current design philosophy and to integrate further with wind turbine substructure design so that efficiencies in installation may be obtained by standardisation. As highlighted elsewhere in this

issue, standardisation is also seen as one of the keys to more cost-effective design and production of jacket-type foundations for turbines.

STX says it believes that the concept of modular, scalable substations also has a role to play in reducing costs. It has developed a new generation of substations called SeeOs (Scalable Efficient Evolved Offshore Station) that it believes can reduce energy costs by reducing delivery time and lowering capex and opex costs.

Because it is a scalable, modular solution for offshore platforms, STX believes that SeeOs can accommodate any power requirement, ranging from 200 megawatts (MW) to 900MW. Interestingly, it can be installed on monopile, jacket or floating foundations, depending on the site. The base module design is a fully enclosed 200/300MW unit that can accommodate any OEM MV GIS, transformer and HV GIS. Two or three of the base modules can be combined to meet any power requirement up to 900MW. In addition to scalability, SeeOs can also be customised to fulfil specific client preferences, maintenance strategies, local regulatory requirements and requirements associated with the distance to shore. These client-specific requirements, such as shunt reactors, harmonic filters, back-up generators, living quarters, workshops or warehouses, will be implemented as add-ons to the base module.

STX says it believes that the design of the SeeOs is such that delivery time could be reduced by 20 per cent and that project capex and operations and maintenance costs could also be reduced by up to 20 per cent. “These efficiency gains are a result of the standardised design which uses 80 per cent common features across all modules,” the company said, noting that SeeOs has also been designed to accommodate the latest technical developments such as 66kV. OWJ

Offshore Wind Journal | 3rd Quarter 2017

22 | SURVEY

Blyth project highlights benefits of technology and early surveys EDF Energy Renewables’ experience of surveying for unexploded ordnance on the Blyth offshore windfarm demonstrates the benefits of conducting a site survey as early as possible, adopting the right strategy, making use of new technology when required and working closely with the authorities

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he Blyth offshore windfarm in the UK is a high-profile demonstration project at which a number of new technologies are due to be demonstrated. It will consist of five MHI Vestas Offshore Wind V164 turbines installed on gravity base foundations with the first use of 66kV export and inter-array cables.

As for all offshore windfarms, in order to minimise installation risk, it was necessary to undertake surveys of the seabed for unexploded ordnance (UXO), inspect any anomalies found and dispose of any confirmed UXO within the requirements set out in the marine licence for the project.

Certain assumptions were made about the likely prevalence of UXO at the site. This was based on early stage site details gathered during the consenting process, which indicated the site would be a relatively low risk.

However, as representatives of EDF Energy Renewables explained in a presentation at Offshore Wind Energy 2017 Conference, a post full investment decision (FID) survey of the windfarm site discovered in excess of 700 potential targets. This presented considerable potential challenges in terms of budget and programme timescale, so EDF was forced to amend its UXO strategy.

The area surveyed had a high level of magnetic shielding due to dumping of dredged material from the Port of Blyth and other dumping from the former power station and marine vessels over the years. A flexible approach was required to contracting and consenting, and this flexibility proved vital for the work to take place at all and

certainly to conclude successfully.

“It became obvious that acoustic profiling technology could be utilised in a more concentrated fashion to ease uncertainty associated with the standard magnetometer derivation of targets and reduce the associated costs,” said EDF. “Ways of better defining what actually presented a threat were investigated. The outcome of these investigations was that the independent UXO specialist carried out additional processing to remove some of the magnetic shielding, and a PanGeo sub-bottom imager (SBI) was used to investigate potential UXO.” Immediate engagement with the consenting authorities on varying the licence was also seen as prudent.

Through the adoption of a flexible approach, EDF was able to adapt quickly to the issues discovered during the detailed site investigation. The use of modified and additional techniques enabled risk to be mitigated to manageable levels in terms of programme and contracting. Working closely and openly with the consenting authorities allowed progress to be made quickly to ensure that consent amendments did not impact the project’s critical path.

In addition, the investigation and detonation contractor replaced the proposed vessel with one with dynamic positioning (DP), which proved to be a very good choice, with the vessel continuing to work through seas as high as 4m whilst still being able to launch a remotely operated vehicle (ROV).

“Although the work was resource demanding, in order to meet the requirements of the programme and consent needs, the use of a good contracting strategy and contractor proved that this type of work can be managed successfully whilst not shortcutting the normal processes,” said the company. “Timing issues were managed with respect to consents and the investigations, but without the ability to make quick decisions, choosing the right contractor and constant communication with the authorities, it would not have been successful.”

Overall, said EDF, the lessons learned from the project include the need to carry out an UXO survey as early as possible – and certainly before FID. “The money spent early will not only give greater clarity to the post-FID budget but will give a full view of the possible issues early enough to be planned into the workstream for the project,” said the company, which noted that early engagement and constant communication with the authorities is vital to prevent expensive delays. The use of a high-spec DP vessel for the investigation also reduced weather-related downtime, and the use of the SBI reduced the target count by a third. OWJ

PanGeo’s sub-bottom imager reduced the target count that EDF needed to deal with by around a third

Offshore Wind Journal | 3rd Quarter 2017

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SURVEY | 23

UNMANNED INSPECTORS CAN PROVIDE COMPREHENSIVE O&M PICTURE

THE OFFSHORE WIND INDUSTRY CONTINUES TO FOCUS ON EVERLARGER TURBINES AS A MEANS OF COST REDUCTION, BUT THERE IS ALSO A HUGE OPPORTUNITY TO REDUCE COSTS BY FOCUSING ON OPERATIONS AND MAINTENANCE

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ecognition that O&M costs can be reduced significantly is leading to greater attention on new vessel concepts and unmanned aerial vehicles (UAVs) or drones. But it doesn’t stop there: autonomous underwater vehicles (AUVs) or unmanned underwater vehicles (UUVs as they are sometimes known) have a potential role to play too.

As OWJ reported recently, a research consortium in the UK has been awarded a £4 million (US$5 million) grant to create remote inspection and repair technologies using robotics and autonomous systems. The aim of the Holistic Operation and Maintenance for Energy from Offshore Windfarms project is to address weaknesses in windfarm asset management and reduce the risks associated with human intervention and inspection.

Now Danish researchers are getting in on the act, and scientists at the Technical University of Denmark (DTU) have inaugurated a laboratory where they will test a modular underwater robot that will be capable of inspecting foundations for offshore wind turbines. They aim to use the robot to inspect turbines initially, but in the longer term, the goal is that unmanned underwater robots will also be able to carry

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Unmanned underwater units that can inspect and interact with offshore installations have already been proposed in the oil and gas industry and could be applied to offshore wind

out repairs on foundations.

Remotely operated vehicles, which have been used in the offshore oil and gas industry for years, are tethered and deployed from a ship. Ships cost a lot of money to build and operate and to man, so why not use an underwater vehicle without a tether that could be pre-programmed to inspect the turbines in an offshore windfarm? UUVs of this type have already been developed to inspect pipelines in the oil and gas industry, although their take-up has been adversely affected by the downturn in that sector.

As the DTU notes, there is a real need for small, flexible,

robust underwater robots that can inspect offshore turbines and rigs. “We have a vision of creating a modular robot that is simple to operate,” said Roberto Galeazzi, an associate professor in the electrical engineering department at DTU. As his colleague Ole Nørrekaer Mortensen, who works in business development at Force Technology, explained, underwater technology is moving quickly in the direction of small AUVs. “Other scientists are working on similar projects, but our robots differ in one key respect in that they are modular, which means that each individual robot is able to work alone or together with

other modules,” said Professor Galeazzi. He suggests that a modular robot could install and replace sensors in a docking station on a foundation to provide continuous monitoring of its condition.

Perceptual Robotics in the UK is investigating the use of remote robotic inspection for offshore wind turbines and has moved quickly from focusing on smart drones for the abovewater inspection of onshore wind turbines to investigating a methodology for whole-turbine inspection of offshore windfarms, including above-water and underwater components.

The methodology described by the company in a paper at Offshore Wind Energy 2017 incorporated the use of UAVs inspecting the exterior of the tower and the blades as well as an AUV that would be used for underwater inspections. Both vehicle types would be operated from an autonomous seaborne platform, the data from both platforms then processed in parallel to form a comprehensive report with actionable information as well as a record allowing for long-term analytics.

At the heart of the autonomous systems is the distributed autonomous intelligence provided by Perceptual Robotics.

The company believes that there are significant gains to be realised with the application of autonomous robotic systems for offshore turbine inspection, particularly given that the scale of offshore turbines and weather conditions present a significant challenge for rope access and manned diving for underwater inspection. Perceptual Robotics believes that smart UAVs and AUVs will significantly expand the operational envelope for inspection, in parallel with reducing the inspection time required to produce a comprehensive report with actionable information. Unlike conventional fault reporting, UAV and AUV data can be stored and post-processed to provide additional information for timely maintenance that can further enhance the long-term efficiency of wind turbines. OWJ

Offshore Wind Journal | 3rd Quarter 2017

24 | TURBINES

ANALYSIS PROVIDES INSIGHT INTO COST-REDUCTION POTENTIAL OF VERY LARGE TURBINES

10MW + turbines could help reduce the cost of energy from offshore wind even further, but their adoption would not be without risk

IT HAS BECOME ACCEPTED WISDOM IN THE OFFSHORE WIND INDUSTRY THAT NEWGENERATION, LARGER TURBINES WILL DRIVE DOWN COSTS, BUT IS THAT REALLY THE CASE, AND WHAT MIGHT THE IMPLICATIONS OF HUGE NEW TURBINES BE ON COSTS ELSEWHERE IN THE SUPPLY CHAIN?

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ecent offshore wind auctions in The Netherlands and Denmark have left many asking the question, how can a project be built at the kind of very much reduced strike prices that won recent tenders?

It is often said that everlarger, more powerful turbines

will play an important role in driving down costs, but without hard data about next-generation turbines from turbine manufacturers, how can project developers be sure that future turbines will provide the kind of cost reduction they require?

Among the questions that need to be asked are:

Offshore Wind Journal | 3rd Quarter 2017

• Will larger offshore wind turbines definitely result in a significantly lower levelised cost of energy (LCOE)?

• What are the risks in larger wind turbines?

• How do larger turbines affect turbine support structures?

• Will installation techniques and operations and maintenance (O&M) strategies need to change to account for large wind turbines?

• How will the layout of windfarms change with larger wind turbines?

“Offshore windfarm developers are working hard on strategies to win future auctions,” said DNV GL. “We want to give them an insight into what next-generation turbines will look like, how they will perform, how turbine support structures need to

change and the impact on the whole project. At this stage, turbine OEMs have not announced detailed designs, but developers need certainty about what is coming next, as do vessel operators and the supply chain.”

To attempt to answer some of these questions, DNV GL explored how the next generation of 10+ megawatt (MW) turbines could contribute to a reduction in LCOE, enabling more competitive projects with reduced strike prices and potentially subsidyfree projects in the future.

Without access to detailed information about newgeneration turbines, it used modelling software to arrive at its results – results that are reassuring in some respects but not in every respect.

As Simon Cox, Ben Chilvers and Fred Davison from DNV GL told delegates at the Offshore Wind Energy 2017 Conference in London in June, their work explored the potential size and performance of next-generation turbines based on detailed modelling using the Bladed wind turbine simulation software, an enhanced version of which was released in late 2016.

They then looked at how loads from the turbine affect turbine support structure design and costs using another suite of programs. Turbine.

Architect is a software tool that has the ability to assess the impact of technology and design on windfarm level, calculating costs and energy

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TURBINES | 25

production based on realistic project and site specifications advance modelling.

The impact of nextgeneration turbines on installation and O&M was assessed using construction planning (O2C) and operations planning (O2M) software. In this way, DNV GL hoped to enable a detailed analysis of the impact of next-generation turbines on capex and opex costs.

Finally, an offshore windfarm was modelled using nextgeneration wind turbines in the WindFarmer windfarm design software in order to enable the impact of 10+ MW turbines on layout design and windfarm energy yield to be analysed.

The yield was then combined with the costs to calculate the impact on LCOE. DNV GL says the results of the work highlighted the technical challenges that arise from increasing turbine size and the potential impact this has on turbine support structures and windfarm design, posing an answer to the question, ‘Is bigger always better for offshore wind turbines?’

The results of DNV GL’s analysis suggest that 10+ MW turbines are achievable using current technology but the cost per MW is expected to increase significantly for these turbines compared to 6–8MW turbines.

The company found that turbine support structures are achievable for next-generation turbines with a reduction in the cost per MW. Additional reductions in the cost per MW of the balance of plant, construction and O&M were also modelled.

The resulting impact on windfarm energy yield and LCOE is still work in progress, with results expected soon.

The technical risks associated with new, much larger offshore wind turbines were also examined in a presentation by Philipp Stukenbrock and Pascal Sommer from 8.2 Consulting AG in Hamburg, Germany. Like DNV GL, they point to the fact that, in recent European auctions, the cost of offshore wind energy has fallen significantly. However, like DNV GL, they also noted that the development of future offshore windfarms relies

heavily on turbines that are currently in the demonstration or design phase.

“Many project developers are struggling to define the best project setup and submit a competitive bid for upcoming auctions,” they said. “Apart from the interfaces in an offshore windfarm, turbine technology and its maintainability is a crucial factor in a developer’s ability to guarantee bid prices per kilowatt hour over the lifetime of a windfarm. Thus, many developers are trying to predict future developments in terms of yield, price and risks.”

In order to mitigate the potential risks involved in construction, installation and operation of future turbines, 8.2 Consulting analysed the development life cycle of offshore wind turbines from the development phase until commercial availability, in order to try to provide a reliable picture about future turbines.

The company assessed all of the major wind turbine suppliers in the European market and their ability to bring new turbines to market. Going

beyond its technology forecast published in 2016, it investigated technical risks involved in the development and adoption of new technology. The analysis focused on MHI Vestas, Siemens, GE Energy and Senvion.

Considering recent development paths and the industrial dynamics of the offshore wind energy industry, the company arrived at an estimate of what rated power future turbines will have, what their power curves might be and when they will be available.

“Project developers and investors involved in the new tender rounds and/or in negotiating projects that have already been awarded will be able to utilise the technology to better understand the risks associated with as yet unproven technology and its influence on windfarm set up,” said 8.2 Consulting. “The result of our work should reduce the uncertainties of project developers and investors and help to mitigate risks associated with new turbines entering the market without a proven track record.”

12MW turbines in sight, says MAKE The pace of technical innovation in the wind energy market continues to be rapid with 12MW offshore wind turbines in sight, according to a new report from MAKE. New wind turbine designs are being introduced to the global market with increasing frequency, a trend that MAKE expects to continue.

Competition among turbine OEMs has intensified in core markets, causing most to innovate and develop new turbine designs.

“All turbine OEMs are exploring methods to differentiate product

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performance and cost, in order to deliver the lowest LCOE,” said MAKE. “Most OEMs are now deploying a platform approach to product development to accelerate design cycles and leverage common components across products.” Doing so is causing turbine life cycles to contract as fierce competition and pressure to lower LCOE sees current products replaced by next-generation platforms.

“In the offshore market, leading OEMs are expected to accelerate turbine growth even faster than the onshore segment,” MAKE said. “The

next generation of 10–12MW turbines are expected in the next couple years. R&D is in full swing at leading turbine manufacturers. Massive 12MW turbines with rotor diameters in excess of 200m are being planned for the offshore market, as turbine size remains the single most important differentiator in the segment.”

Dong Energy would seem to agree with this kind of analysis. Benj Sykes, vice president, head of asset management and UK country manager, has gone on record saying he anticipates that

much larger turbines could be installed before long. “If you wind the clock back four or five years, this scale of technology was considered very ambitious,” he said of the 8MW wind turbines. “Now, you can see them in reality, commercially deployed. It’s very difficult to say where we will ultimately get to. We’re already talking about the need to scale up the current turbine range to 12MW to 15MW as part of the cost-reduction journey. I think we will see that scale of turbine come in but we’re not sure from who or when,” he said. OWJ

Offshore Wind Journal | 3rd Quarter 2017

26 | COST REDUCTION

The cost of UK offshore wind projects will fall as they have elsewhere in Europe

THE NEXT UK CFD AUCTION

– HOW WILL IT PLAY OUT?

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he upcoming results of the contract for difference (CFD) auction in the UK will be scrutinised closely, following the record low prices contracted in last year’s auctions in the Netherlands and Denmark and this year’s bids by Dong Energy and EnBW at zero subsidy in Germany.

I can foresee people jumping to conclusions, many of them partly or wholly wrong, and lots of high horses being mounted in supposed defence of the poor, ripped-off UK consumer. So before the madness starts, it’s helpful to take a measured look at where we are, what we might expect to see and what that could mean.

As Giles Hundleby* explains, the cost of energy from the next tranche of offshore windfarms built in the UK will be lower than previous projects but won’t be as low as some in Europe because – at least for the time being – the auction model used there is different to those used in the Netherlands and Denmark

Offshore Wind Journal | 3rd Quarter 2017

The next UK round is a competition between different developers (or consortiums of developers), each with a different windfarm, bidding for a CFD power purchase agreement. The projects must be operational by 2023 to 2025, and we expect around 2 gigawatts (GW) to be awarded to a maximum of four projects, with the biggest project being between 700 megawatts (MW) and 1,200MW in size.

The CFD includes the cost of the offshore and onshore substations and transmission cables between the two.

BVG Associates (BVGA) analysis suggests that the levelised cost of energy (LCOE) (including transmission

system) for the potential UK projects varies between £70 per megawatt hour (MWh) and £80/MWh (€80–92/ MWh), based on 6.5 per cent weighted average cost of capital (WACC) and a 25-year project life. Due to the CFD being for 15 years, this would imply CFD bids around £80/ MWh. However, if developers pull all of the LCOE levers at their disposal in the way they did in the other recent auctions, volumes could be higher and prices lower.

In contrast, three of the four winning bids in the recent German offshore wind auction for projects coming online in 2025 rejected the comfort of a minimum reference price. By

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COST REDUCTION | 27

contracting to deliver energy without even a ‘subsidy-free’ minimum reference price, the windfarm developers must be expecting to make a better return based on the wholesale market price than they could under a subsidy regime.

BVGA has calculated the LCOE of these windfarms taking into account their characteristics, expectations about new technology and costs from 2025, published information and statements from the winning bidders Dong Energy and EnBW. The use of much larger turbines (13MW or more) was implied by both bidders. This is in line with expectations of the technology that will just be coming available by the time these projects are being built. The sites are also windier on average than many other sites bidding for offshore wind support.

Treating the two neighbouring Dong Energy sites (OWP West and Borkum Rifgrund 2 West) as a single site, BVGA calculates an average LCOE (in today’s terms and including the cost of the grid connection) of around £48/ MWh (€55/MWh) at 6.5 per cent WACC. The refusal of a governmentbacked minimum reference price does appear to make the commercial viability of these windfarms as stand-alone projects riskier. The time horizon for them to come online further complicates that risk. Those risks and timescales present an interesting dilemma for all stakeholders for this project. If they turn out to be optimistic on LCOE and/or overly pessimistic on the wholesale price side, will the developers still want to proceed with a potentially lossmaking project? In the converse situation, will consumers and governments eventually find that they are paying more than they needed to?

In July 2016, the announcement of the Borssele I and II auction results was

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greeted by the offshore wind industry with a mixture of astonishment, delight and (from competitors) a little concern.

Dong Energy had beaten the €100/MWh LCOE barrier well ahead of the 2020 target that industry previously committed to.

Dong Energy’s bid secured 15 years of SDE+ (the Dutch equivalent of CFD) funding for the project followed by the ability to sell energy at market price for the rest of the project’s life.

Dong Energy’s bid was actually at €72.7/MWh, which implies an LCOE of about €68/MWh (or £59/MWh) excluding transmission. The Dutch Government has already paid for key elements of project development activity and is taking the risk on the transmission connection for which it will add a (fairly modest) €14/MWh to the costs, giving a total project LCOE of about €82/MWh (£71/MWh). That was a dramatic decrease from other levels seen at the time.

The Shell consortium that won last December’s Netherlands auction for an offshore windfarm at Borssele III and IV achieved an even lower bid price of €54.5/MWh, implying an LCOE including transmission of around €70/ MWh (£61/MWh).

When Vattenfall’s bid price of €50/MWh for Kriegers Flak was announced, it seemed at the time a crazily low price that surprised much of the industry.

The fact is that, with the same technology and timing, the windfarm costs should be pretty much the same at Kriegers Flak as it is at Borssele I and II (see above). That’s because Borssele’s advantages of being a little bit bigger and a little bit windier are mostly offset by Kriegers Flak being a little bit closer to shore and having a little better wave conditions. Kriegers Flak has to be operational by the end of 2021, and while Borssele could be as late as mid-2020s, we expect it to be delivered

earlier than that. Both are in similar water depth, and both bid prices exclude transmission and some development costs.

But the LCOE for Kriegers Flak implied by the €50/MWh bid price is around 20 per cent lower than the equivalent LCOE for Borssele I and II – around €68/MWh (£59/MWh).

Some commentators have indicated that Vattenfall will use a next-generation 10+ MW turbine at Kriegers Flak (though having these ready for a project completing in five years’ time is a bit of a stretch) and is banking on reducing operational costs through the project life, but our calculations suggest this explains at most a quarter of the benefit. The explanation appears to lie either in increased revenues, reduced project returns or a combination of the two.

It’s clear that, in all these recent auctions, the developers are using all six levers of LCOE: energy production, annual operating cost, total capital cost, project lifespan, WACC and timing of capital expenditure.

The Netherlands system of doing development and

Giles Hundleby: “CfD system does not deliver as much competition as the Dutch system”

having developers compete for sites delivers benefit in reducing risks (and thus WACC) as well as removing costs from developers.

The German system is an interim measure before it moves to a new system similar to the Netherlands.

However, though superficially attractive, zero bids add risk to the process and are not necessarily helpful to ensuring capacity is built and delivers to consumers at lowest cost.

The CFD system used in the UK provides opportunity for consumers to ‘claw back’ subsidies if strike prices are below the market price for energy supply but does not deliver as much competition as the Netherlands system due to developers bidding on different projects.

The winning strike prices in the upcoming UK auctions will likely imply slightly higher LCOE than the other markets, but the UK LCOE will not be grossly out of step after adjusting for timing (and assumed technology), project sizes, wind speeds, depths, distances to port and synergies with other projects.

The UK LCOE will be marginally higher due to the less directly competitive situation and the carrying of development risk by each different developer.

A combination of the best elements of the UK and Dutch systems could be the optimum way forward. The sooner the UK moves to the Netherlands-style system while retaining use of CFDs, the more level the LCOE playing field will be across the whole of the European offshore wind market and the more transparent the results. To reap the further benefits will require a clearer definition of the future pipeline of projects so developers can plan accordingly, not project by project as now. OWJ *Giles Hundleby is a director at BVG Associates

Offshore Wind Journal | 3rd Quarter 2017

28 | INNOVATIONS

WATER-DRIVEN PILING SYSTEM COULD ENHANCE MONOPILE INSTALLATION NOISE MITIGATION DURING PILE DRIVING HAS LONG BEEN AN ISSUE IN THE OFFSHORE WIND INDUSTRY, AS HAS THE GROWING SIZE OF MONOPILES – THE BLUE HAMMER DEPARTS FROM CONVENTION AND COULD PROVIDE A SOLUTION

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eveloped by a Fistuca, a Dutch company that started life as a spin-off from the faculty of mechanical engineering at Eindhoven University of Technology in which crane manufacturer Huisman has a stake, the Blue Hammer is a pile-driving solution unlike any other.

Rather than hammering a monopile into the ground, the Blue Hammer concept developed by Fistuca uses acceleration of a water column by a gas mixture to provide the driving force – a mechanism that can deliver a large amount of energy without exciting undue vibration in a monopile.

As Jasper Winkes, founder and director of Fistuca, and Henrik Bisgaard Clausen, a senior consultant at Ramboll in Denmark, told the Offshore Wind Energy 2017 Conference in London in June, a prototype of the new concept has been successfully tested.

“The combustion of a gas mixture leads to an increase in pressure. This pressure creates an upward acceleration of the water and a downward force that pushes the pile into the seabed,” Mr Winkes explained.

“Another powerful downward blow is delivered to the pile when the water mass falls. After the exhaust gases have been released, the cycle is repeated.”

Mr Winkes believes that ‘blue piling’ has a number

of advantages compared to conventional impact hammers.

Firstly, the hammer produces very low levels of noise compared to conventional hammers. This means that noise reduction

The Blue Hammer promises to be quieter than conventional technology

Offshore Wind Journal | 3rd Quarter 2017

measures – which can add significantly to the cost of piling operations – are much less likely to be required. The underwater noise level produced by the Blue Hammer is approximately 20dB lower than that produced by conventional hydraulic hammers. “This means that noise mitigation is unnecessary in most conditions,” Mr Winkes said.

Secondly, compared to the impact of a conventional hammer, the duration of the impact from the Blue Hammer is much longer, which minimises fatigue damage to the monopile.

“Conventional hammers exert force over a short period of time,” Mr Winkes explained.

“The Blue Hammer delivers a blow over a period of more than 100 milliseconds. This makes the force delivered by the system more efficient. The water-based blows ensure a gradual build-up of force on the monopile, reducing tensile stresses in the pile and reducing acceleration levels. Fewer blows and lower stress levels reduce installation fatigue.”

A third and increasingly important benefit of the Blue Hammer, given the rapid growth in the size of offshore wind turbines and in their foundations, is that it is able to drive largediameter piles.

Another advantage is that the concept is compatible with having secondary attachments mounted on the monopile before pile driving is undertaken. Lower acceleration levels allow piles to be partially pre-assembled prior

to piling, reducing the loads on components such as flanges.

Based on a generic monopile design and a typical North Sea site, Ramboll has demonstrated that monopiles can be driven into the seabed using the Blue Hammer and that this can be done with pre-mounted attachments such as boat landings, internal platforms and cathodic protection equipment installed. This leads to a reduction in the amount of work needed on a monopile once it has been installed offshore.

Apart from being able to drive larger-diameter monopiles, Blue Hammer is also well suited to doing so in deeper water.

“It is suitable for all types of conventional piling and foundation work using jacket (pin) piles as well as so-called XL monopiles. It interfaces with the pile in the same way as conventional piling technology, so the pile itself doesn’t need to be adapted in any way,” Mr Winkes concluded, noting that Huisman Equipment is currently building a Blue25M, which he believes will be the largest and most powerful hammer in the world, on behalf of Fistuca.

It is due to be delivered by the end of 2017 and will be tested at Port of Rotterdam in the first quarter of 2018 and then offshore in the second quarter of 2018. Several major players in the offshoire wind industry have shown interest in supporting the demonstration. OWJ

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SCOUR PROTECTION | 31

CONTINUOUS MONITORING

CAN COMBAT EFFECTS OF SCOUR

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hanges in seabed level around a vertical structure, otherwise known as scour, can present big problems across the offshore sector. Scour pits can be caused by tidal currents moving around foundations and can impact the integrity of offshore structures by gradually washing away the supporting sediments. The result of this can, and has, led to the unnecessary premature decommissioning of expensive offshore assets.

The extent and effect of scour is of particular importance around the nearshore environment, where the tidal effects are amplified due to the relatively shallow waters involved. This brings the issue into the spotlight for all manner of renewables developments, but particularly the offshore wind sector, where the infrastructure is in place on such a large scale.

As Philip Bishop and Lucy Maclennan from Fugro in the UK explained at the Offshore Wind Energy 2017 Conference in London in June, UK Round 1 and 2 windfarms have begun experiencing the effects of scour, leading to newer windfarm developers increasingly taking notice of this potential threat. Some sites have been known to witness up to 20m of sediment being eroded away from the foundations, and this can lead to early decommissioning as turbines may only be piled 30–40m into the seabed.

Bathymetry surveys, traditionally used for

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Sonar manufacturers say cost-effective technology is available that can monitor the effects of scour around the foundations of offshore windfarms

monitoring scour, can miss short-term scour pits generated by extreme conditions, but correlated with other oceanographic measurements, in situ scour monitors installed on foundations can provide invaluable information on the integrity of offshore assets.

Scour monitors are secured to foundations below lowest astronomical tide (LAT), ideally with one device placed on each principal tidal axis, ensuring the most extreme effects are monitored. The devices use four acoustic beams configured at four angles from the vertical and can be programmed to capture data at user-specific sampling rates. A depth sounding is calculated from the reflection of each beam off the seabed and can produce a time series of seabed elevation.

Data can be transmitted in real time via a cable and displayed on a dedicated website or remain logged on the instrument for postprocessing. Measurements of

local tide, waves and currents can be collected concurrently to evaluate how environmental conditions affect the generation of scour and which conditions pose the greatest threat.

Bishop and Maclennan said results from individual windfarms are highly site-specific as scour is predominantly driven by factors such as seabed morphology, sediment type and local environmental conditions as well as the age of the windfarm. They would expect a high correlation between extreme weather conditions and short-term scour generation. Longer-term scour pits are usually caused by a combination of sitespecific factors and require further investigation due to the potential for impact on the structural integrity.

“Scour monitors offer a simple and cost-effective solution that require a minimal amount of maintenance following initial installation. Data can highlight which turbines are most at risk, ensuring plans can be made well in advance to secure their long-term operational future,” they said.

“Compared to traditional bathymetry surveys, scour monitors provide data on a 24/7 basis, irrespective of weather, and this allows for the assessment of both shortterm and long-term scour pits.

Continuous monitoring allows offshore operators to decide on appropriate protective measures, such as rock dumping, to mitigate against further scouring and damage to the structure. In addition

Scour is of particular importance in marine renewable energy, particularly the offshore wind sector

to providing site monitoring, the scour data could also be used for numerical modelling initiatives, contributing to future windfarm development and foundation engineering design.”

Other manufacturers, such as Kongsberg, agree with this approach. Pavel Kapricheski, product and application manager, subsea monitoring at Kongsberg Maritime in Hamburg, Germany, described the use of a 3D scour monitoring system. He advocated moving away from conventional underwater inspection to permanent structural 3D monitoring that can provide real-time data “from the seabed to the office” linked to a cost-efficient intelligent control system with advanced data-processing capabilities. OWJ

Offshore Wind Journal | 3rd Quarter 2017

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Move Forward with Confidence

TRAINING | 33

Competence and outputs the key, rather than inputs Chris Streatfield, director of Forge Risk and a former director of health and safety at RenewableUK, argues that too much attention is focused on the delivery of training, rather than the assessment of competence

Mr Streatfield says clients and employers should take greater ownership of training and not assume that others will ensure competence

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very responsible employer recognises the value in investing in training and skills. The overall quality of health and safety training in the renewables sector is good and compares well with related sectors.

However, we remain fixated on ‘inputs’ – such as attendance and participation – rather than ‘outputs,’ that is, skills, knowledge and ability. In other words, too much focus is on training delivery and not enough on assessing competence.

The renewables sector and wind in particular deserve some credit in developing what are now global health and safety training standards in less than a decade. The UK took the lead in defining training standards for wind technicians for work at height and rescue and sea survival. This was shortly followed by the major OEMs and developers agreeing what are now the default international standards via the Global Wind Organisation

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(GWO). Combined with the enhanced governance and verification processes that we have seen in recent years (such as Winda, the global wind industry training records database), safety training has a good story to tell.

However, safety performance compared to benchmark sectors remains worse than we would like, and the next phase in the cost reductions being sought is going to present some enormous challenges. We still see too many contracting strategies that are compliance-driven and that certification (safety tickets) are in effect the default basis of determining competence both of organisations and individuals.

While this may be efficient from a short-term project management perspective, we see limited evidence that the focus on training as opposed to competence is a sustainable approach in the long run.

So what is competence? It can be described as the

Offshore Wind Journal | 3rd Quarter 2017

34 | TRAINING

combination of training, skills, experience and knowledge that a person has and their ability to apply them to perform a task safely.

Other factors, such as attitude and physical ability, can also affect someone’s competence.

This article doesn’t aim to solve every training issue – not least as UK plc has been underinvesting in training and skills for decades. However, we can see there are three key areas to enhance safety standards but also improve the wider sector capability in managing risk. These are adding value to existing baseline training, focusing on competence requirements for safetycritical roles and recognising the role and importance of soft skills.

Baseline training: Once an employer has fulfilled its duty to eliminate risks so far as is reasonably practicable, it is required to provide such information, instruction, training and supervision as is necessary to address the residual risks. A person can be considered competent if they have suitable and sufficient understanding of the risks and safe systems of work that are relevant to the location where they are working; knowledge of the specific tasks to be undertaken and the risks that they entail; training, experience and ability to undertake their assigned duties; and sufficient understanding to recognise their own limitations.

Industry training standards (such as GWO) provide a good baseline but alone will not demonstrate an individual is competent.

Many companies build on this baseline training to ensure employees and contractors are competent. However, the move to more outsourcing of technicians and related roles increases the risk that the verification of essential safety competencies could fall through the cracks.

To reduce this risk, the industry needs to ensure that employees/contractors are provided with suitable task/role-specific health and safety induction and training, especially at a project/ site level, regular briefings and updates on new, live or dynamic health and safety risks and regular ‘hands-on’ refresher training to minimise the risk of skills fade.

Safety-critical roles: It is understandable why training focuses on technicians and frontline employees – not least as the perceived immediate cause/human error often appears to happen on the ‘shop floor’. However, experience in managing risks in more complex environments makes it clear that developing the competence of individuals working in safetycritical roles is essential. The safety-critical nature of some

roles is obvious. However, in many cases, the safety risks and consequences that could follow a bad decision are less clear.

There is no accepted right approach, so it is essential that organisations undertake a more comprehensive training needs analysis that integrates the specific needs of individual roles alongside the wider risk management processes carried out.

Examples of roles and activities that could be deemed safety-critical in the wind sector include hazard/activity-specific roles such as lifting supervisors, cable jointers, technical and safety trainers and ergonomists and support roles such as marine coordinators, client reps, health and safety advisers, inspectors, site/project managers, operational controllers and logistics personnel. These are indicative only – the main point is to identify potentially safety-critical roles, understand the consequences of failure and then develop a risk-based training plan that addresses the technical and safety gaps that need to be addressed.

Soft skills: Although we are seeing the emergence of a wider range of delivery and assessment options, such as role play, exercises and interactive and e-learning, health and safety training is still dominated by ‘talk and chalk’ with too little experiential hands-on delivery. The baseline and safetycritical training needs summarised above are calling out for innovation to make them more engaging and relevant to those on the receiving end. However, even if this is improved, its value will be limited unless we also invest in the soft skills to support the role and individual.

This is a vast area with extensive academic and educational theory to support those interested. Examples that are relevant include: personal skills such as communications, coaching/ mentoring, decision making, team work, problem solving; and self-reliance, such as situational awareness, interpersonal skills, self-awareness, mindfulness and personal safety.

Clients and employers should be encouraged to take greater ownership of training and development and not assume or rely that others will ensure workers are competent.

Industry-endorsed ‘tickets’ provide a helpful baseline and benchmark. However, if we are to grow the industry, reduce costs and improve safety performance, there must be a collective investment in our workforce and in turn that we create the ‘learning organisations’ that differentiate the average from world-class performing businesses.

Simulator training for enhanced safety Simulator training has come to be widely used in the offshore oil and gas and offshore vessel sectors but is less widely used in the offshore wind industry. However, as Søren Einar Veierland, a business development manager at Kongsberg Digital in Norway, told the Offshore Wind Energy 2017 Conference, simulator training could be widely used

in the offshore wind industry to train and assess competency and ensure safe end costefficient operations.

“Simulator training can provide trainees with physical, behavioural and visual realism to simulate daily operations as well as emergency situations,” said Mr Veierland, noting that one of their biggest advantages is that they can be used to train

Offshore Wind Journal | 3rd Quarter 2017

personnel in inherently risky, potentially dangerous operations that cannot be taught at sea.

“Using a simulator, they can be fully exercised in an advanced simulator, preparing a student how to respond to escalating scenarios and manage crises,” he explained.

In Mr Veierland’s view, simulators can be used to train personnel for most offshore

wind operations, such as ship handling for turbine installation vessels including dynamic positioning in close proximity of windfarm installations, maritime operations and walkto-work simulations for crew transfer vessels and foundation installation operations involving heavy-lift vessels, cablelay, operations by remotely operated vehicles and trenching. OWJ

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CORROSION CONTROL | 37

CONSORTIUM TACKLES BARRIERS TO ADOPTION OF GAME-CHANGING CORROSION CONTROL CONCEPT WIDELY USED IN THE OFFSHORE OIL AND GAS INDUSTRY, THERMALLY SPRAYED ALUMINIUM PROVIDES AN ALTERNATIVE TO THE USE OF CONVENTIONAL COATINGS AND ANODES ON FOUNDATIONS IF BARRIERS TO ADOPTION CAN BE OVERCOME

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orrosion protection and management of foundations for offshore wind turbines is a potentially costly undertaking in terms of initial capital outlay and in longterm maintenance. The current solution of paint and sacrificial anodes not only slows foundation construction time but has a limited lifetime that requires frequent inspection and maintenance activities.

Anodes require additional secondary steelwork to be added to a foundation, and paint requires many days to dry, slowing production times and adding cost. Typical marine paints will degrade over time (particularly in the splash and tidal zone) under the action of UV radiation and marine fouling and can be damaged by impact. Organic paint coatings provide no protection to the underlying steel when damaged and corrodes rapidly.

The Welding Institute (TWI) in the UK believes that a more cost-effective solution could be at hand in the form of thermally sprayed aluminium (TSA), which, it believes, has the potential to entirely replace paint and anodes, providing robust, long-term corrosion protection that saves money not only in O&M but also in initial capital outlay.

Although TSA is used extensively in the offshore oil and gas industry on platforms and in pipeline applications

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and successful use of TSA has been reported on tension leg elements and production risers in deep water, it has yet to be embraced by the offshore wind industry. Now, however, an industry consortium of which TWI is a part, which is funded

by Innovate UK, intends to change that.

“Replacing conventional corrosion protection, based on paint and sacrificial anodes, with a single coating of TSA can provide a highly reliable coating that requires less maintenance and repair and also the cost of manufacturing foundations,” it says. “While often seen as an expensive coating option, TSA can offer significant savings during fabrication as there is no need for sacrificial anodes, secondary steelwork or extended curing times for multiple coatings of paint.”

As Henry Begg, a senior project leader at TWI, told the Offshore Wind Energy 2017 Conference, apart from its perceived cost, another challenge of using TSA in the offshore wind industry that the consortium is addressing is quantifying its ability to provide local cathodic protection in regions of damage. If sacrificial anode use is to be reduced or eliminated, a high level of confidence is required in the ability of the coating to prevent corrosion of the underlying steel.

To gain further insight into the potential of TSA coatings TWI used electrochemical methods to provide quantitative data on their corrosion rates in a range of conditions. The effect of coating damage was investigated, including data on area ratio of acceptable damage, geometric distribution of any through-thickness defects (holidays) present and absolute size of holiday areas.

The interaction of TSA with imposed cathodic protection was also investigated to provide data on current drain of any galvanic anodes when used in conjunction with TSA coatings, allowing cathodic protection systems to be efficiently designed.

Mr Begg said electrochemical studies showed that TSA was able to tolerate damage in excess of 15 per cent of the total area, while still providing protection to the steel substrate. Local pH changes in the region of damage as a result of the cathodic protection action of the coating result in the precipitation of calcareous material from seawater. Such deposits act to reduce the area of exposed steel, enabling the coating to continue to provide protection without being consumed at a high rate. The interaction of imposed cathodic protection was combined with damage tolerance studies, providing

TWI believes that thermally sprayed aluminium has a number of potential benefits on foundations

industry with the data needed to design cathodic protection systems in cases where sections of structures must remain uncoated (such as for inspection purposes).

“By addressing barriers to TSA adoption in the offshore wind sector, costs associated with the installation and maintenance of foundations can be significantly reduced,” Mr Begg said. “Providing foundation designers and developers with data on the corrosion performance of TSA under a range of conditions will afford the required levels of confidence in the technology and facilitates its more widespread adoption.” OWJ

Offshore Wind Journal | 3rd Quarter 2017

38 | LiDAR

LiDAR ON COURSE TO BECOME MEASUREMENT TECHNOLOGY OF CHOICE

LiDAR IS CONTINUING TO GAIN GROUND IN THE OFFSHORE WIND INDUSTRY, WHERE IT IS FAST BECOMING ESTABLISHED FOR WIND RESOURCE ASSESSMENT AND POWER CURVE VERIFICATION

LiDAR experts say the technology is gaining quickly in acceptance in the offshore wind industry

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iDAR (light detection and ranging) has become the technology of choice for offshore wind measurement campaigns, saving millions in costs, thanks to efforts at manufacturers, developers and the Carbon Trust’s Offshore Wind Accelerator. That was the consensus of opinion at a seminar at Offshore Wind Energy 2017 at which industry leaders discussed the advantages of the technology.

LiDAR has been replacing met masts to become by far the most important measurement tool for wind resource assessment and power curve verification. Over the last several years, said experts speaking at the seminar, LiDAR technology has proven its ability to provide wind measurements that are every bit as reliable as met masts. They also claimed that LiDARs are faster, easier and much less expensive to deploy, enabling significant development and operational cost reductions. LiDAR also has health and safety advantages because it is so much easier to deploy and does not require the use of installation vessels and cranes.

Offshore Wind Journal | 3rd Quarter 2017

At the seminar, hosted by Leosphere, wind measurement experts explained that years of successful LiDAR validation campaigns have enabled the industry to choose the technology over met masts for feasibility studies and power curve verification tests.

“Experience has taught us that the uncertainty levels offered

by LiDARs are at least on par with those offered by met masts.

Although we still encounter performance misconceptions surrounding LiDAR technology, it is now hopefully merely a question of time before the industry as a whole recognises the technology, and IEC standards are adapted accordingly,” said Anders Thoft Marcussen, head of measurements at Dong Energy and chairman of the LiDAR seminar. In practice, the use of nacelle mounted LiDARs is already frequently required in the turbine supply agreement for power curve verification testing, even if LiDAR measurements are not yet covered by IEC standards.

Met masts cannot compete with LiDAR on cost grounds, attendees at the seminar were told, highlighting examples such

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LiDAR | 39

as the Beatrice Offshore Wind Farm Ltd (BOWL), where the wind measurement campaign was carried out without the use of a met mast. BOWL chose instead to install two vertical profiler LiDARs which enabled it to start the measurement campaign much earlier and without the significant costs associated with installing an offshore met mast.

For an offshore project developed by RES, the installation of a met mast – estimated at €12 million – was ruled out in favour of a single fixed LiDAR, coupled with two floating LiDARs. The fixed LiDAR, installed on a nearby lighthouse, and the floating LiDARs located at points across the windfarm zone, enabled the company to secure reliable, bankable data and make millions in cost savings compared with the use of a met mast.

Alongside its floating LiDAR roadmap and recently-published floating LiDAR recommended practice, the Carbon Trust has co-ordinated a pioneering industry effort to test and validate four floating LiDAR systems. The project has helped de-risk and validate several floating LiDAR systems whilst allowing developers to learn about the different systems and the practical lessons in undertaking these campaigns.

In the trials conducted under the auspices of the Offshore Wind Accelerator initiative, validation trials were conducted on four different floating LiDAR systems, each being deployed for a minimum of six months at an existing or prospective windfarm site and independently validated by a third party against existing met masts. Three of the four trials were project managed by a developer to allow them hands-on experience in deploying floating LiDAR, whilst the fourth was managed by the system supplier themselves.

The result of the programme was the independent validation of four floating LiDAR systems as well as invaluable lessons in deploying the floating LiDAR devices. These lessons include health and safety lessons which will be important to disseminate more widely to the industry, as well as more nuanced lessons of maximising data availability and maintenance strategies.

The conclusions are that floating LiDAR systems deliver highly accurate and dependable data for wind resource assessments, and that the future of wind resource assessment offshore is swiftly transitioning to floating LiDAR. Moreover, with more and more systems now available competition will enable further costs reductions to be achieved.

Representatives of RES and Leosphere told delegates that Offshore Wind Accelerator carried out a four month trial of two pairs of scanning LiDARs which were installed in Dublin Bay and validated against two vertical profiling LiDARs to determine their accuracy and precision.

The devices were set up to measure wind speeds in a nominal offshore windfarm within the bay, which stretched to over 10km from the devices at its furthest point. Each device was to measure wind speeds at a range of heights at eight set points offshore and validated against fixed vertical LiDAR. The system suppliers were left to devise their own scanning patterns and algorithms to process the data, and the trial was carried out completely blind with validation by RES as an independent third party.

RES and Leosphere said the results “showed phenomenal accuracy at ranges never tested before in offshore wind” (>13km) and demonstrated that whilst single Doppler will need further work to be viable for offshore wind, dual Doppler has given very convincing results for both manufacturers. The results also showed the effect of deploying scanning LiDAR on a potential annual energy production, with uncertainty of the P90/P50 ratio being brought down by 1-2 per cent (exceedance probabilities for wind

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energy production are expressed as P values (the P stands for probability). P90 denotes the level of annual wind-driven electricity generation that is forecasted to be exceeded 90 per cent of the year. P50 is average level of generation: half of the year’s output is expected to surpass this level, and the other half is predicted to fall below it).

“The main conclusion of the trial is that scanning LiDAR can work for offshore wind and can produce very accurate wind speed measurements at very long ranges,” said RES and Leosphere, noting that “there is further work to be done in order to improve some of the algorithms of the devices themselves but for certain sites this technology can have real cost reduction benefits.”

Beatriz Cañadillas from UL International (formerly DEWI) also highlighted some of the many benefits of LiDAR, noting that in addition to being more cost-effective than a met mast use of LiDAR also saved time and is more flexible than the alternatives.

Eliminating the met mast also means that there are no tower impacts on measurements. Among the many potential applications of LiDAR in the offshore wind industry she highlighted wind resource/ site assessment; power curve verification; turbine performance monitoring; correcting yaw misalignment; shear measurements; wake effect measurement and the provision of data for turbine control (including fatigue and extreme loads). She said work remains to be done to improve/review estimation of wind LiDAR uncertainties in general and improved turbulence estimation.

Representatives of EDF Energies Nouvelles also told the seminar that LiDAR could provide robust, accurate and reliable data, but noted that they are not yet accepted everywhere in the wind industry and noted that nacelle-based LiDAR is not always accepted by manufacturers for contractual purposes. They also noted that it is sometimes difficult to reach agreement between a manufacturer and developer regarding power curve verification using LiDAR. OWJ

In brief…

• AXYS Technologies has confirmed that it has met all of the Stage 3 performance criteria outlined in the OWA Roadmap.

Since the initial deployment of its FLiDAR system in 2009, along with the acquisition of FLiDAR NV in September 2015, AXYS’ FLiDAR buoys have successfully completed or have underway 20 commercial offshore wind assessment campaigns and 16 offshore met mast validations.

• ZephIR Lidar has confirmed that its UK wind LiDAR production centre will open by the end of 2017, in response to what it described as “increasing demand for more accurate wind measurements in the development, construction and operation of windfarms worldwide.”

The site near Ledbury also has a new research and development studio and is part of a wider complex that includes the first remote sensing test site in the UK at Pershore. The centre will cater for existing ZephIR models, future products and creates what the company described as “a step change in manufacturing capacity.”

• Titan Technologies Corporation has ordered two Fraunhofer IWES LiDAR buoys to conduct surveys of the wind resource at the Zhangpu and Changle offshore windfarms off the coast of Fujian province in China. This will be the first time a floating LiDAR system has been used for offshore wind measurements in China.

Offshore Wind Journal | 3rd Quarter 2017

40 |TURBINE SUPPORT VESSELS

GERMAN DECISION DRIVES RATES UP AND SAFETY DOWN In April, the German maritime authority, BG Verkehr, made a decision that has greatly restricted the employment of many experienced masters of foreign crew transfer vessels on German windfarms. As Philip Woodcock* explains, the move has not only driven up operating costs, but will also adversely affect safety

The decision by the BG Verkehr has driven up operating costs on German windfarms and could adversely affect safety

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he German authorities concluded that the Maritime and Coastguard Agency (MCA)-issued Seafarers’ Training, Certification and Watchkeeping (STCW) II/2 Master Code Vessel <200t Certificate of Competence (CoC) for vessels up to 200gt is not a valid CoC, recognised by the International Maritime Organisation (IMO).

Without consulting the MCA or industry bodies such as the National Workboat Association (NWA), they started to board and detain foreign-flagged crew transfer vessels (CTVs) working in German Waters.

The only way to get this detention lifted was to place a master qualified to handle vessels of up to 3,000gt on board. However, these ‘big ship’ masters are rarely accustomed to operating small, high-speed vessels, and the new requirement therefore threatens to compromise the safety of passengers and crew. At least one recent safety incident is already being linked to the decision. Furthermore, it has needlessly elevated operational costs – with an impact that is felt throughout the supply chain.

A recent conversation overheard between a vessel operator and a contractor with a job in Germany was telling. The CTV operator offered the vessel with his existing certified crew, and placed the obligation on the

Offshore Wind Journal | 3rd Quarter 2017

contractor to supply an additional master qualified to handle vessels of up to 3,000gt, at their expense, to drink coffee in the wheelhouse with the required CoC. This resulted in the contractor having to increase his offer to the wind farm by €500 per day just to satisfy a poorly thought out decision by a regulator.

It is ironic that Germany has taken a step that will ultimately reduce safety levels right at the start of the busy summer season, and at a time when the industry has been making great strides in improving competence and further reducing the low levels of risk experienced by CTV operators.

Over the last few years, the National Workboat Association (NWA) in particular has been vocal about the need to reduce the industry skills gap, and driving CTV masters to upgrade to the MCA-issued STCW II/2 Master Code Vessel CoC for vessels up to 200gt. However, at the same time, it has also stressed that this certification alone does not ensure competence when it comes to the safe transport and transfer of personnel within the offshore wind industry.

These efforts have been accompanied and supported by industry-wide advances, as evidenced by the G+ issued Good Practice Guidelines ‘The Safe Management of Small Service Vessels in the Offshore Wind Industry,’

and the International Marine Contractors Association (IMCA) Guidance Document C 017, ‘Guidance on Competence Assurance and Assessments: Marine Roles for Small Workboats.’ The UK government’s safety body, The Health & Safety Executive (HSE), has been also working in collaboration with the industry to look at perceived risks during the transfer process. In its assessment, the HSE has involved all stakeholders to ensure that their concerns are recognised and addressed, to avoid making knee-jerk decisions with unforeseen consequences.

In this context, the German decision seems even more counterintuitive, and this may suggest that other factors are at play. Many believe that one possible motive behind this action is a desire to protect and create jobs within the German maritime sector.

Traditionally, Germany has had a strong merchant shipping industry, but very limited exposure to offshore oil and gas and marine contracting. Germany’s fishing fleet is also one of the smallest in the European Union, with less than 2,700 crewmen employed, which means that these traditional sources of competent crew for the CTV industry are limited.

Given the overall decline in using western European officers in general merchant shipping, this could also be a means of using regulatory powers to find work for unemployed container ship officers. This cabotage strategy is common in Africa, Brazil and America, but goes against the free movement of labour espoused by the European Union.

Whatever the motivation, since the German authorities first took action in April, the industry has been coming to terms with the uncertainty the decision has generated. The NWA has been issuing regular information bulletins, negotiating with the MCA and communicating directly with the operators of German windfarms to make them aware of the action, and to help them understand the consequential risks that were added overnight to their operations.

While the industry waits for more clarity, it is imperative that efforts continue to improve safety standards, raise awareness of these issues, and mitigate risks in areas where it still has an opportunity to do so. OWJ *Philip Woodcock, general manager, Workships Contractors

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TURBINE SUPPORT VESSELS | 41

UAV limitations need to be addressed in order to maximise offshore utility Unmanned aerial vehicles or drones undoubtedly have a big role to play in the offshore wind industry but teething problems involving their use from vessels need to be addressed before they can become widespread, as Philip Woodcock* explains

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he use of unmanned aerial vehicles (UAVs) or drones as they are known is accepted practice in the onshore windfarm industry. Use of the correct provider should result in quicker and cheaper inspections with no reduction in quality.

The most significant advantage from drone use is through reducing or eliminating exposure of humans to risk during routine inspection work. High definition cameras coupled to blade mapping reporting software has even allowed some operators to accurately automate the reporting process. However, their entry into the offshore wind industry however has not been as smooth as onshore.

Drones in the offshore and maritime industries are common in certain circumstances. On an oil platform, a drone team can quickly give the offshore installation manager a quick indication of the status of maintenance on hard-to-reach areas such as the outboard side of the superstructure or stacked containers, under lifeboat platforms and helidecks, while the equipment and team is small enough to be flown in and out by helicopter.

Shipping companies are using drones to inspect the inside of ballast tanks and cargo holds on large ships to eliminate the risks of enclosed space entry and working at heights in a cost effective fashion. However, the offshore wind industry has yet to see the same results consistently due to a few fundamental differences in environment.

In offshore wind, drones tend to be flown from the small

Unmanned aerial vehicles are widely used on land but their use at sea is more complicated

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crew transfer vessels that are used to transport personnel within a windfarm. It is common for technicians to get seasick on the passage out in anything but the calmest weather. However, the drone pilot, who is expected to spend hours staring at a small screen piloting a drone in close proximity to the tower or blades, is exposed for much longer periods and is at a much higher risk from motion sickness.

This introduces the hazards of poor inspection quality, reduced number of inspections and striking the turbine, blade or vessel through pilot error. However, this risk will eventually be eliminated when windfarms have a suitably high-speed data connection in field which will allow the pilots to be based ashore and only the launch and recovery performed offshore by experienced seamen.

The recovery of drones on small vessels has also proved to be problematic as many small unmanned units are still landed by flying into the operatorâ&#x20AC;&#x2122;s hand. When the vessel is pitching and rolling in a seaway, this method of recovery will reduce flying time because any incident offshore that results in a loss of control will also cause the drone and data to be lost into the sea with little chance of recovery.

Thus the operator will err on the side of caution and not fly in marginal conditions.

All drones are limited in the amount of mission equipment they can carry because more weight will result in reduced flying time.

In the offshore wind industry, when the contractor tries to get the optimum performance from a day in field, unpredictable weather conditions will also reduce flying times.

In an onshore scenario, the only cost is the drone team driving to a windfarm, while offshore there is also the vessel, its crew and fuel to be considered as well.

As windfarms are constructed in areas of high average winds, this can result in many smaller drones having limited flying time as they are limited to 8m/s wind speed. The biggest improvement in the use of unmanned aerial vehicles is a wider weather window, with speeds up to 14m/s.

In one recent case it was reported that gusting winds combined with recovery problems resulted in the contractor falling significantly behind the inspection schedule. In that particular example, the contractor stated that it would have been quicker and more efficient to have performed the inspection scope with traditional rope access techniques.

The future of routine blade and tower inspection in the offshore wind industry definitely involves the use of UAVs as the hazard to workers working at heights is reduced or eliminated altogether.

However, much work is needed to improve operational performance in the challenging conditions found offshore before they can compete effectively with traditional rope access techniques. OWJ *Philip Woodcock, general manager, Workships Contractors

Offshore Wind Journal | 3rd Quarter 2017

42 | TURBINE SUPPORT VESSELS

DYNAMIC POSITIONING GIVES RENEWABLES SERVICE VESSEL AN EDGE DAMEN IN THE NETHERLANDS HAS BEEN BUILDING MULTI CAT WORKBOATS FOR YEARS – THE LATEST EVOLUTION OF THE DESIGN IS A WORKHORSE SPECIFICALLY INTENDED FOR THE RENEWABLES INDUSTRY

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amen recently delivered the first example of its renewables service vessel (RSV ) 3315, a newdesign developed in close co-operation with Scottish company Delta Marine for work in the offshore wind industry. Delta Marine took delivery of its first Damen vessel 12 years ago, and the Shetland-based company now has four Damen Multi Cat vessels in its fleet as well as one it manages.

The first in the new series was named Voe Vanguard at Damen Shipyards Hardinxveld. A week later, Voe Vanguard was off to its first offshore windfarm, the Walney Extension project.

The RSV 3315 design can undertake all duties normally expected of a Multi Cat but also has a spacious, unobstructed deck, class 2 dynamic positioning (DP2) and dedicated four-point mooring.

The Dutch ship designer and builder describes the evolved Multi Cat as a “serious workhorse” with powerful propulsion generating a bollard pull of 42 tonnes whilst remaining under 500gt. Added to this is a standard outfit of cranes and winches. With the option of DP2, a four-point mooring system, two good size cranes and hydraulic shark jaws with guide pins, the vessel is designed to be able to undertake a wide range of duties. An AHT winch can be deployed over both stern and bow. Safety and visibility were key design guidelines along with the largest possible deck space, enabling the RSV 3315 to load equipment, carousels or remotely operated vehicles or be used as a walk-to-work vessel. The foredeck provides room for containers.

David McNaugthan, Delta Marine general manager, says the decision to invest in a vessel specifically tailored for renewables was taken around four years ago.

“We knew at Damen we would get a good project and good quality backup.

Offshore Wind Journal | 3rd Quarter 2017

Voe Vanguard can undertake all of the duties normally expected of a Multi Cat and also has a spacious, unobstructed deck, DP2 and dedicated four-point mooring

“We were particularly interested in having DP2 capability. This vessel is suitable for offshore wind but also for tidal projects, where it can stay in position using DP in some pretty strong currents,” said the owner.

Delta Marine and Damen adapted the traditional Multi Cat design by moving the wheelhouse forward and leaving the aft deck open. Additionally, it was important to make sure the vessel was under the 500gt mark to keep costs down.

“The vessel is diesel-electric and has four azimuths with a large stern thruster. It is also very flexible, with a shallow draught of only 2.6m. The two aft azimuths can swing up into the hull, and we can easily switch from DP1 to DP2 mode,” said Delta Marine.

In addition, Voe Vanguard has two powerful cranes, one of which has a

capacity of 15 tonnes with an outreach of 20m. “With these, we can carry and lift an awful lot for a wide variety of tasks.” The vessel has comfortable accommodation for 18 crew.

Delta Marine said the DP2 system is “very important for our clients” and “every single job is crying out for DP2.”

Jos van Woerkum, managing director of Damen Shipyards Hardinxveld, said the Dutch company has been working on the design of the vessel with Delta Marine since 2013.

“Delta Marine gave us a sketch and outlined their requirements, and I think Damen has built exactly what they wanted,” he said. “I think the renewables service vessel has the potential to be a big success for Damen once it has proved itself in the market.” OWJ

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44 | INSTALLATION VESSELS

NEW-GENERATION INSTALLERS

RESPOND TO NEED FOR HEAVIER, HIGHER LIFTS

JACK-UP VESSELS HAVE LONG BEEN THE VESSEL OF CHOICE FOR TURBINE INSTALLATION, BUT LARGER, HEAVIER TURBINES HAVE PROMPTED A RETHINK AND A NUMBER OF NEW DESIGNS

GustoMSC’s NG-20000X is characterised by a high variable load, the ability to install in deep water and an integrated telescopic leg crane

Offshore Wind Journal | 3rd Quarter 2017

O

ver the last decade, self-propelled jack-ups have evolved into autonomous platforms able to carry turbine components on deck, position themselves using dynamic positioning (DP) and provide a stable working platform on a robust jacking system designed for frequent operations. Combined with a dedicated crane, these features have enabled them to safely install the latest generation of 6–8 megawatt (MW) turbines.

Over time, the design and operation of units such as these has evolved in the direction of process optimisation, in which the main focus has been on minimising installation time per turbine, thus enabling faster overall field development.

However, the trend towards larger turbines exceeding the 6–8MW size range has presented new challenges, such as a requirement for increased lifting height, the ability to lift heavier loads and increased crane reach. This trend has also increased focus on the issues related to the dynamics between the turbine and the installation vessel.

The latest generation of installation vessels can be enhanced and upgraded, but the industry has come to realise that a new generation of vessels will ultimately be required for 8–10+ MW turbines. Bigger is almost always better as far as installation vessels are concerned, but greater operational flexibility is also required.

Responding to some of the above-mentioned requirements, GustoMSC has unveiled a new turbine/foundation vessel, the NG-2000X, which is characterised by a high variable load and the ability to install in deep water. Equipped with the GustoMSC integrated telescopic leg crane, the NG-20000X can install heavy foundations, and when the boom is fully extended, it reaches adequate lifting height and capacity to install future generation wind turbine components, the company said.

“A different approach is required for the future turbines with capacities beyond 10MW,” said GustoMSC of the new jack-up unit, noting that it enjoys the advantages of the proven VSD jacking system and a large unobstructed deck area. “The variable load capacity of 16,500 tonnes enables contractors to make a round trip carrying six complete sets of wind turbine components with a turbine weight of 1,000 tonnes or carry seven 900-tonne jacket foundations, optimising the cost per installed turbine or foundation,” said the company. “A key feature of the design is the innovative combination of high hoisting height for wind turbine installation and heavy load capability for foundation installation.”

To combine these two requirements, GustoMSC has developed a telescopic leg crane. “By introducing a telescopic boom that

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INSTALLATION VESSELS | 45

features a very high hook height when extended (1,250 tonnes at 160m) and increased hoisting capacity when retracted (2,500 tonnes at 120m), it is possible to break the cycle of extremely long booms and increasing crane weights, resulting in a more economic crane design and increased variable load available for operations,” GustoMSC said.

GustoMSC has also proposed using liquefied natural gas (LNG) as a fuel for new-generation vessels but not just to reduce emissions. It also believes that, apart from the environmental benefits of LNG-fuelled ships, closely matching the LNG propulsion system to the operational profile of a vessel can provide a significant reduction in capex.

“A capex-optimised design approach further enhances the business case for an LNG-fuelled installation vessel,” the company claims. “Optimising the LNG capacity installed to the long-term average operational profile is a very effective way of reducing the capex.”

As highlighted previously in OWJ, a number of companies have ordered vessels targeting the growing market for ships capable of decommissioning offshore oil and gas platforms and installing jacket foundations for offshore wind turbines. Among the forthcoming newbuilds targeting the decommissioning and offshore wind markets are Orion, DEME’s new vessel, and Bokalift 1, based on an existing semi-submersible heavy-lift ship that the Dutch company is converting into a 3,000-tonne crane ship.

The new vessel for Boskalis will combine the 3,000-tonne lifting capacity revolving crane with a deck area of 165m x 43m and a DP2 positioning capability. Like Orion, it will be used to install jackets and monopiles for offshore wind turbines and to remove obsolete oil and gas platforms and transport. Boskalis says it could also be used to transport and install certain types of newbuild oil and gas production platforms. Having DP2 will mean that the vessel will not rely on the installation of an anchor spread. The vessel will have accommodation for 149 people and a helicopter deck for offshore transfers. Delivery is expected at the beginning of 2018. A sister vessel is also scheduled for conversion into another 3,000-tonne capacity crane vessel.

Bokalift 1 will be capable of lifting 3,000 tonnes at a radius of 28m and 1,200 tonnes at 50m. The load a heavy-lift crane can lift is important, but so too is the height to which it can lift a load. Using its main block, the crane on the vessel, which is being built by Huisman, will be capable of lifting a load to 90m above deck at a radius of 30m and 99m at a 35m radius.

The 216m long vessel has a breadth of 43m, moulded draught of 13m and operating draught of approximately 8.5m. The deck will be strengthened to 25 tonnes/m2. The machinery takes the form of four 3,840kW Wärtsilä engines and two 4,800kW Bergen engines with a 1,110kW auxiliary engine from Wärtsilä. Bokalift 1 will have a ballast capacity of 2 x 1,500m3/hr and an anti-heeling system with a capacity of 8 x 2,000m3/hr. The vessel will have a transit speed of 14 knots.

In foundation installation mode for the offshore wind market, the vessel would load itself with jackets or other types of foundation using its crane and, having arrived at the location of the windfarm, would lift the foundations and stab them into place on pre-installed pin piles using the crane whilst in DP mode.

New types of jack-up vessels have also recently been proposed, among them one from SeaOwls and Ulstein. The SOUL (after SeaOwls and Ulstein) heavy-lift jack-up was unveiled at the Offshore Wind Journal Conference in London in February this year.

The companies say the cruciform structural layout of the jack-up makes the patent-pending solution more than 10 per cent lighter than

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The innovative SOUL heavy jack-up makes use of a cruciform structural layout

conventional jack-up vessels. “In combination with a high-capacity crane, SOUL enables operators to take the next step in developing offshore windfarms,” they said. The concept was developed with the installation of next-generation wind turbines in the 10–12MW class in mind but is also suitable for installing 6–8MW units.

“The development of this novel jack-up vessel is the logical next step in our strategy to broaden our portfolio and support the offshore wind industry with more efficient assets,” said Ulstein Group deputy chief executive Tore Ulstein. “Combining the track record in heavy-lift vessel designs from Ulstein in the Netherlands and SeaOwls’ experience in jack-up technology has resulted in an innovative jack-up vessel concept based on proven technology.”

The companies note that scaling up conventional heavy-lift jackup vessel designs is challenging due to the disproportional weight increase compared to gain in variable deck load but believe that their design overcomes this problem.

“We noticed this created uncertainty among turbine manufacturers, windfarm operators and installation contractors about how to install larger turbines,” said Erik Snijders, founder and managing director at Rotterdam-based SeaOwls. “So we went back to the optimal jack-up design, a square platform with the legs spaced out as far as possible. Rotating the platform by 45 degrees provided a natural bow shape with two legs and the crane on the vessel’s centreline.”

“This seemingly simple twist in the design allowed us to make a huge improvement in operations,” said Ulstein Design & Solutions BV deputy managing director Bram Lambregts. “With the main crane around the stern leg, optimal main deck reach and over-theside lifting capabilities is created, and as the hull now houses much larger leg footings, bearing pressures on the seabed are reduced, while the wake of the spud cans does not interfere with the inflow to the propulsion thrusters.”

The SOUL series will be available in various sizes, allowing the transport of three to six 10–12MW turbines. All loading and installation operations can be performed without the need for ballast water. OWJ

Offshore Wind Journal | 3rd Quarter 2017

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BEST OF THE WEB | 47

BEST OF THE WEB Offshore Wind Journal’s website covers the latest developments in the offshore wind sector. Our news coverage is now exclusively online and free to read. Here are some of the most popular stories covered over the last few months

UK, said “We are delighted to see Dong Energy’s Race Bank development receiving blades made in Hull. This first load out represents a significant milestone in the story of how, in just a few years, we have helped increase the UK economic benefit of lower cost offshore wind and helped make the Humber region a hub for low-cost, green energy expertise.”

Installation of the blades and rest of the components is on track with 25 turbines installed to date. Race Bank is expected to be fully operational in 2018. http://bit.ly/2uBTvdM

Blyth offshore windfam hits new milestone The Blyth offshore windfarm demonstration project in the UK has reached an important milestone with the first turbine foundation making its journey up the River Tyne on route to its final destination.

EDF Energy Renewables is building the Blyth Offshore Demonstrator Windfarm after taking over responsibility for the scheme from Narec (now ORE Catapult) in October 2014. The project will see five wind turbines with a total generating capacity of 41.5 megawatts installed around 6.5km off the coast of Blyth.

Concrete gravity-based foundations (GBFs) form part of the project and are being installed using a ‘float and submerge’ technique – the first time this method has been used for offshore wind turbines.

http://bit.ly/2uqoHx2

Jan De Nul Group’s jack-up vessel Vole au vent has installed the last blade on the final wind turbine at the Tahkoluoto offshore windfarm in Finland.

The first phase of construction of the windfarm was completed in 2016. The second phase started in April 2017. Vole au vent will be demobilising from the Finnish project shortly and starting preparations for its next project at Blyth in the UK. Wind power company Suomen Hyötytuuli Oy selected Jan De Nul NV, part of the Jan De Nul Group, as the main contractor for the marine aspects of the Tahkoluoto offshore windfarm in 2016.

GeoSea set to buy A2SEA

http://bit.ly/2uuHRBP

First blades from Siemens UK factory en route to Race Bank windfarm

Subsea cable specialist JDR to be acquired by TFKable

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providing water-blocked power cores for its cable and umbilical systems.

Monika Cupiał-Zgryzek, chief executive officer of TFKable, said “TFKable is a strategic investor with a long-term vision for JDR, sufficient resources to support its continued growth, and vast knowledge of the market. TFKable is planning to maintain JDR’s operations in current locations, providing new opportunities for the local employees and business partners, and offering our customers innovative solutions.”

The transaction, which is subject to receipt of required regulatory approval and consents and other customary closing conditions, is expected to close in the third quarter of 2017.

Jan de Nul completes turbine installation on Finnish offshore windfarm

http://bit.ly/2tlOnec

The first wind turbine blades manufactured at the Siemens blade factory in Hull have been completed and delivered to the Race Bank offshore windfarm. Siemens’ blade factory in Hull opened in December 2016.

Clark MacFarlane, managing director Siemens Gamesa Renewable Energy

owjonline.com

JDR Cable Systems (Holdings) Ltd ( JDR), one of the leading suppliers of power cables for the offshore wind industry, is to be acquired by TELE-FONIKA Kable in Poland.

TELE-FONIKA Kable (TFKable) is a leading producer of wires and cables. Both companies have a long history of collaboration, with TFKable being JDR’s business partner

Belgium’s marine engineering project specialist GeoSea is to buy A2SEA of Denmark from Dong Energy and Siemens.

An agreement was signed early in July 2017 but the transaction is conditional upon authority approval so is expected to be completed in the third quarter of 2017.

A2SEA has been owned by those two partners since 2009, “when both companies needed to consolidate their position in the offshore wind market,” a statement issued

by GeoSea’s parent group Deme said. Now, “owning A2SEA is no longer within the scope of their core businesses and therefore the divestment came naturally,” it went on.

It will continue to operate out of Denmark with offshore wind turbine service and installation and the managing director of GeoSea, Luc Vandenbulcke, said its activities form “a strong and complementary fit with GeoSea’s operations.” He said that the combined organisation “will be well positioned to provide a broader range of integrated services and solutions to offshore wind energy customers.” He also paid tribute to A2SEA’s “highly skilled and specialised employees.” http://bit.ly/2sTOGYT

Offshore Wind Journal | 3rd Quarter 2017

48 | PROFILE

2017 AN IMPORTANT ONE

FOR BASQUE SUPPLY CHAIN AS WINDBOX COMES TOGETHER

S José Ignacio Hormaeche: “WINDBOX provides the offshore wind industry with an opportunity to test and validate new technology”

pain does not have any offshore windfarms but the supply chain in the country has long-standing experience in wind energy. It is focusing much of its effort on development and testing of technology for multi-megawatt turbines used in the offshore wind energy industry, as José Ignacio Hormaeche, managing director of the Basque Energy Cluster, a non-profit association comprising more than 100 organisations involved in energy in the Basque Country, told the Offshore Wind Energy 2017 conference in London in June.

Mr Hormaeche holds an MSc in Civil Engineering from the Polytechnic University of Madrid an MBA from the University of Deusto, Bilbao. Previously, he worked for seven years as managing director at the Basque Energy Agency (EVE), an agency of the Basque government.

From 1998 to February 2006, he worked at Gamesa (now Siemens Gamesa Renewable Energy). He was appointedchief operations officer of Gamesa in 2004.

The energy cluster he currently leads has been developing ‘WINDBOX’ – in which a consortium of Basque companies including turbine manufacturers Gamesa and Adwen and component manufacturers including Hine Renovables, Laulagun, Glual, Wec, Antec, Matz-Erreka, are developing an advanced manufacturing centre that will be capable of integrate and testing subsystems for multimegawatt wind turbines – since 2014. Their aim is to enhance the capabilities of Basque companies in the wind power sector and help them to improve their position in the international market.

Mr Hormaeche explained that the objectives of WINDBOX are to reduce the levelised cost of energy by developing and testing components and products for wind turbines, and to provide Basque and other manufacturers with access to cutting-edge testing facilities, thus improving their competitiveness in the global market. Other objectives include validation of integrated systems, independent assessment, and component testing

Offshore Wind Journal | 3rd Quarter 2017

for all kinds of wind turbines, with a particular focus on new-generation offshore wind turbines.

Mr Hormaeche told the conference that WINDBOX will provide a suite of testing facilities to support the development of new products. To this end, the partners in the project are cooperating in the specification, engineering, design and commissioning of equipment for the construction of five test benches for components and subsystems.

The test benches will simulate operating conditions for wind turbines particularly accurately and allow a number of elements to be tested at component and system level, including pitch systems, generator slip rings, blade bearings (including the hub and connections), yaw systems, and bolted joints, including connections between the parts of a wind turbine.

A hydraulically operated pitch test bench that was designed to test pitch actuation systems and components under similar conditions to those found on a windfarm has been up and running since November 2015 and tests are ongoing on a complete pitch system. A generator slip ring test bench is currently being commissioned, and will be used to test and optimise generator slip rings.

A blade bearing test bench is currently under construction and should be operational by the end of 2017. It will be used to undertake tests on the hub, blade bearings, bearing hub and blade bearing joints. The yaw test bench should also be operational by the end of 2017, and will be used to test and validate yaw systems. The test bench for bolted joints is in the concept design phase.

Once all of the test benches are up and running at IK-Tekniker, an alliance of technology and R&D facilities in Eibar, Spain, the WINDBOX association will own and operate the facilities.

“Applications from interested parties who want to have their products validated by an independent body with cutting edge facilities, including turbine, system and component manufacturers – particularly those working in the offshore wind market – are welcome,” Mr Hormaeche concluded. OWJ

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