Resource May 2014

The official journal of the Institute of Waste Management of Southern Africa

Promoting integrated resources management

Landfill

Post-consumer PET recycling

Sustainability

Solutions to emissions reduction

Energy efficiency

Transforming waste into power

ISSN 1680-4902 R50.00 (incl VAT) • Vol 16, No 2, May 2014

Exposed geomembrane solar caps

Recycling

Institute of Waste Management of Southern Africa

Expert Opinion Ex “Geotextiles offer a better alternative to conventional construction materials like sand and stone aggregate in landfills.” Cheri Scholtz of PETCO and Chris Els of Kaytech

is printed on 100% recycled paper

contents

12

Landfill

20

Nuclear waste

22

Sustainability

26

Energy efficiency

39

Renewables

www.3smedia.co.za ISSN 1680-4902, Volume 16, No.2, May 2014 The ofſcial journal of the Institute of Waste Management of Southern Africa

Promoting integrated resources management

Landfill

Recycling

Post-consumer PET recycling

Sustainability

Solutions to emissions reduction

Energy efficiency

Transforming waste into power

The RéSource team stands firmly behind environmental preservation. As such, RéSource is printed on 100% recycled paper and uses no dyes or varnishes. The magazine is saddle stitched to ensure that no glues are required in the binding process.

ISSN 1680-4902 R50.00 (incl VAT) • Vol 16, No 2, May 2014

Exposed geomembrane solar caps

Institute of Waste Management of Southern Africa

Expert Opinion Ex “Geotextiles offer a better alternative to conventional construction materials like sand and stone aggregate in landfills.” Cheri Scholtz of

is printed on 100% recycled paper

PETCO and Chris Els of Kaytech

Cover story PPC goes from grey to green

6

RéSource offers advertisers an ideal platform to ensure maximum exposure of their brand. Companies are afforded the opportunity of publishing a cover story and a cover picture to promote their products and services to an appropriate audience.

Please call Christine Pretorius on +27 (0)11 465 6273 to secure your booking. The article does not represent the views of the Institute of Waste Management of Southern Africa, or those of the publisher.

African energy

Regulars President’s comment

3

Addressing the water-

Editor’s comment

5

energy nexus More competitive electricity

Landfill

market required

Exposed geomembrane solar caps

9

Solid waste compacting

12 15

Power savings are as impor tant as power stations

Ser ving the recycling market

16

Recycling

renewable power

29

Minimising energy waste in heavy-duty enterprises

Post-consumer PET recycling alive and well

18

Nuclear waste 20

Sustainability

32

Technical paper Landfills’ new regulator y requirements

34

Renewables SAPG comparison to

22

stand-alone CSP

in association with infrastructure news

26

Energy efficiency

Hot seat

Sustainable solutions to emissions reduction

25

Transforming SA’s waste into

The ins and outs of waste compaction

Monitoring nuclear waste

24

infrastructure4

39

}

www.infrastructurene.ws

RéSource May 2014 – 1

President’s comment

Waste Amendment Bill Streamlined implementation or punitive measure?

W

hen the Waste Act Amendment Bill was published for comment in July 2013, the explanator y notice indicated that the purpose of the amendment bill is to address certain implementation challenges that have been experienced with the Waste Act, 2008 and to provide the minister with a discretionar y power to establish a waste management agency when necessar y.

During the parliamentar y process preceding the approval of the Waste Amendment Bill [B 32B-2013] we have learnt that the establishment of the Waste Management Agency (now called the Waste Management Bureau) is a given and that a pricing strategy for waste management charges must be published in the Gazette within three months of the commencement of the amendment act.

The definition of waste is also amended, and now includes a list of waste streams contained in a schedule. The Waste Amendment Bill (version 32B) has been passed on 18 March 2014 and is on its way to the president for assent.

This is a totally new approach to waste management and regulation in South Africa, raising a number of concerns for the sector. Therefore, the IWMSA have invited Mark Gordon (DDG: chemicals and waste management) of the Depar tment of Environmental Affairs and his team to address the sector and shed some light on these new developments.

If you want to learn more about these and other new developments on the regulatory

front, join WasteCon 2014 and get the facts straight from the proverbial ‘horse’s mouth’. Make sure that you don’t miss out!

I am pleased to announce that delegates at WasteCon 2014 can look forward to a ver y exciting and full programme in Somerset West from 6 to 10 October 2014. If you have not yet registered, I would encourage you to do so immediately, as space is limited and the interest overwhelming. A big thank you to all the authors who have submitted abstracts; we have managed to accommodate 90 papers in the programme. Delegates can therefore look forward to four parallel sessions, covering a wide range of interesting and relevant topics. I also wish to thank all the exhibitors that booked stands for the event as we have an interesting lineup and WasteCon 2014 promises to have something for everyone.

Other exciting news is that the IWMSA council is planning a workshop to revitalise the chapters in our neighbouring countries.

The chapters have been in existence for some years already, but have slowly faded over time. In recent times, there seems to be a renewed interest in Botswana, Namibia, Zimbabwe and Zambia. The national council therefore took a decision to invite representatives from these chapters and prospective chapters to a workshop to revive the IWMSA’s SADC footprint. I will report on the outcome of the workshop in the next edition of RéSource.

Having a technical advisor of the calibre of Peter Davies on board has been a great

blessing to the IWMSA. When I approached Davies to take up this position, I was totally blown away by his loyalty. He gracefully accepted the position, but instead of negotiating compensation for his time, he offered his services free of charge. Davies, welcome on board and thank you for your selflessness and loyalty to the IWMSA. Looking for ward to meeting you all at WasteCon 2014!

Regards Suzan Oelofse President: IWMSA

Patron members of the IWMSA

RéSource May 2014 – 3

Editor‘s comment Publisher: Elizabeth Shorten Editor: Maryke Foulds Tel: +27 (0)11 233 2600 Head of design: Frédérick Danton Senior designer: Hayley Mendelow Designer: Kirsty Galloway Chief sub-editor: Tristan Snijders Sub-editor: Beatrix Knopjes Contributors: Dr Suzan Oelofse, Mark Roberts, Sipho Dube, Lisa Parkes, Johannes Cilliers, Andrew Etsinger, Paul Fitzsimon, Tim Schweikert, Jack Ward Client services & Production manager: Antois-Leigh Botma Production coordinator: Jacqueline Modise Financial manager: Andrew Lobban Marketing manager: Hestelle Robinson Digital manager: Esther Louw Distribution manager: Nomsa Masina Distribution coordinator: Asha Pursotham Administrator: Tonya Hebenton Printers: United Litho Johannesburg Tel: +27 (0)11 402 0571 Advertising sales: Tazz Porter Tel: +27 (0)11 465 5452 Cell: +27 (0)82 318 3908 tazz@connect.co.za

Publisher: MEDIA No.4, 5th Avenue Rivonia, 2191 PO Box 92026, Norwood 2117 Tel: +27 (0)11 233 2600 Share Call: 086 003 3300 Fax: +27 (0)11 234 7274/5 www.3smedia.co.za Annual subscription: subs@3smedia. co.za R200.00 (incl VAT) South Africa ISSN 1680-4902 The Institute of Waste Management of Southern Africa Tel: +27 (0)11 675 3462 Email: iwmsa@telkomsa.net All material herein RéSource is copyright-protected and may not be reproduced either in whole or in part without the prior written permission of the publisher. The views and opinions expressed in the magazine do not necessarily reflect those of the publisher or editor, but those of the author or other contributors under whose name contributions may appear, unless a contributor expresses a viewpoint or opinion in his or her capacity as an elected office bearer of a company, group or association. © Copyright 2014. All rights reserved.

RéSource is endorsed by:

Changing with the times D

uring our recent market survey of RéSource magazine we were incredibly pleased to note that our readers, on the whole, find the magazine a helpful and interesting read. The research has shown that the waste-management industry respects and trusts the RéSource magazine. An impressive 79% of respondents thought the publication extremely valuable. All respondents indicated that they use the current and back issues as a source of reference. We were also humbled by how satisfied respondents were with the RéSource team’s performance, with 88% of respondents rating the team’s performance as excellent.

But, as the waste market continues to evolve, it is of great importance to keep up with other waste management trends such as that of energy savings. It is with this in mind that we have decided to broaden the scope of the publication, now focusing on issues such as energy savings as well as renewables and alternative energy options. RéSource is and will remain the official voice of the Institute of Waste Management of South Africa and remains focused in its attention to these topics.

We are slowly moving towards the WasteCon 2014 conference which is being held in Somerset West, Cape Town, this year. This important conference and exhibition will put you in touch with all relevant players in the waste management market so be sure to confirm your attendance timeously. In preparation for this event, we again have an interesting and informative mix of articles for your perusal. Of particular interest is the article by Dr Suzan Oelofse, president of the IWMSA, who looks at development in the waste act. We are also looking at the exciting developments in solar capping of landfills. Bringing up the rear are the latest statistics and trends in PET recycling as well as contributions from some big names WASTECON 2014 will be held from in alternative energy solutions 6 to 10 October, 2014 at NH The Lord Charles Hotel, Somerset West, which is nestled amidst the natural and energy savings. beauty of the Cape Winelands.

I hope you enjoy this issue The theme chosen for this year’s conference is “Wired of RéSource and, as always, For Waste: Value * Grow * Sustain”. look forward to your comments “Wired” implies that WasteCon 2014, the International Conference, is well positioned to provide solutions and suggestions on how to and inspiration for change and transformation, with improve the editorial quality of a multitude of specialists, national and international, regularly attending, sharing their insight and lessons the magazine. learnt. The goal of this multi-day conference is to reenergise change and offer solutions for debate.

Maryke Foulds

RéSource May 2014 – 5

Cover story

PPC goes from grey to green The Green Building Council of South Africa (GBCSA), an independent, non-profit company that was formed in 2007 to lead the greening of South Africa’s built environment, has given PPC’s new headquarters a 4-star rating.

6 – RéSource May 2014

Cover story

L

ocated in the middle of the hustle and bustle of the northern Johannesburg business centre, it was imperative that PPC became wary of its own environmental footprint.

Eastgate 20 on Katherine Street, Sandton, now houses one of the largest cement suppliers in Southern Africa. The new building is strategically designed to efficiently reduce energy and water.

The Green Star rating system from the GBCSA was designed to provide the commercial property industry with an objective measurement for green buildings, and to create and reward environmental leadership in the property industry. A 4-star rating recognises a building for its best practices.

Eastgate 20 consumes less energy To consume less energy, Eastgate 20 has been designed to utilise efficient lighting, which is only activated when an area is occupied, almost giving the incumbent the feeling that they light up the room. Further to this, the design has enabled the building to take advantage of natural light, reducing the building’s electricity demands during office hours.

“We have also made considerable progress through our new air-conditioning system. It uses inverter technology for the compressors – the speed is controlled so that cooling is provided as needed and the motors do not just stop and start,” says Tshilidzi Dlamini, PPC’s group sustainability and environmental manager.

A power converter is a power electronic device that changes the supply voltage from a fixed 50 cycles per second mains AC waveform to a variable frequency and variable voltage waveform. This enables a standard fixed speed AC motor to be run at variable speeds, and for the speed of the motor to be accurately controlled. AC motors that are not fitted with a power converter are only capable of running at full speed (switched on) or zero speed (switched off).

With a power converter fitted, the output of the driven machine (e.g. pump, fan, compressor) can be adjusted and controlled to deliver the exact output volume, ie water- and airflow, required to meet demand, and, therefore, energy is not wasted.

“The cost of installing a power converter is significant, but so are the energy savings that can be achieved. Yes, technology like this is expensive, but the payback period from savings in electrical energy costs can be less than a year, making it an extremely viable option,” says Chris Yelland, managing director of EE Publishers.

LEFT Eastgate 20 in Sandton BELOW The imposing front entrance

ABOUT PPC s the leading supplier of cement and related products in Southern Africa, PPC has nine manufacturing facilities and three milling depots in South Africa, Botswana and Zimbabwe. Related products include aggregates from quarries in Gauteng and Botswana. PPC Lime supplies metallurgical-grade lime and burnt dolomite.

A

Water preservation crucial to the cement business Eastgate 20 is expected to make a significant reduction in the usage of potable water through the installation of water-efficient fittings for taps, urinals and toilets.

Furthermore, Eastgate 20 has also increased the quality of the water in the adjacent environments. PPC has a stormwater-treatment site, adjacent to Eastgate 20, where they treat all the water from their premises and that of the neighbouring sites to ensure that it is clean before it flows into the river.

“Normally during a storm event, rainwater runs off hard surfaces into stormwater drains and is directed into the nearest river to avert flooding. In built-up areas, the abnormally amplified increase in water flow during storm events disrupts the natural balance of the ecosystem and the river’s ability to function as part of a healthy ecosystem,” says Dlamini.

+27 (0)11 386 9000 www.ppc.co.za

RéSource May 2014 – 7

Institute news

IWMSA training geared towards positive change Training offered by the IWMSA is focused on providing education on sustainable environmental best practices, promoting the science and technology of waste management and supporting international, national and regional trends in waste management.

A

ccording to IWMSA president, Dr Suzan Oelofse, training is geared towards improving the overall delivery of waste management services in South Africa, so that the industry can become world class.

‘The more people we can reach through our training programmes, the sooner we will

witness positive changes within the industry,' says Oelofse. ‘We are very pleased with the quality and depth of training that took place in 2013. Our footprint is spreading and we are seeing a new level of commitment and interest from delegates as well as very exciting partnerships with training providers.' The IWMSA receives numerous requests for tailor-made training sessions and is able to assist with both accredited and non-accredited courses.

The IWMSA was contracted by the Southern African Wildlife College (SAWC) in Mpumalanga, a regional training institution that has been in operation for 16 years, to present accredited waste management training to 50 unemployed youth from the Bushbuckridge and Thaba Chweu municipalities. The training is part of a three-year project, now in its second year, funded by the Department of Environmental Affairs, under the Youth Environment Service programme.

‘Now that the training is complete, the learners are ultimately expected to participate in theory contact sessions arranged by SAWC, complete workplace assessments and also

participate in community service activities within the Bushbuckridge or Thaba Chweu municipalities. The community services will include collecting recyclable waste, sorting waste, packaging the waste for collection through a buy-back programme, reducing waste going to landfill sites, and establishing SMME cooperatives in waste management,' says Oelofse.

‘With the assistance of our facilitators, we were able to provide world-class training where learners actively participated in discussions, group work activities and question-and-answer sessions. Although learners indicated that they have limited knowledge about waste management, most of them were interested in knowing more about the field, in order to make a positive contribution. It definitely was very encouraging,' explains Oelofse.

‘We have outstanding non-accredited material, excellent training tools and highly skilled trainers and facilitators,' says Oelofse. ‘Our training department is expanding and this means we can reach a much wider audience and make a larger impact on the environment.

‘The SAWC training session is the first of many to be held in 2014. The IWMSA is currently preparing for training sessions to be held in Randburg, Midrand, Durban and Cape Town. We urge members – new and old – to contact us regarding the many programmes we offer to meet their waste management training needs,” concludes Oelofse.

The IWMSA is a multi-disciplinary nonprofit association committed to the protection of the environment and people of Southern Africa from the effects of poor waste management by supporting sustainable best practical environmental options.

For more information on the IWMSA: www.iwmsa.co.za IWMSA is also on Facebook: www.facebook.com/IWMSA Unemployed youths queue to receive accredited waste management training

8 – RéSource May 2014

Landfill

Exposed geomembrane solar caps

By Mark Roberts and Sipho Dube*

The grass is not always greener. The adage proves true at the Hickory Ridge Landfill in Atlanta, Georgia, as well as the other exposed geomembrane solar energy caps.

R

epublic Services, a leading solidwaste management firm in North America used exposed geomembrane solar-cap technology to transform the Hickory Ridge Landfill from an operating landfill that had reached its permitted capacity into a commercial-scale solar-energy-generating facility. The exposed geomembrane solar cap is an innovative new technology that combines an enhanced geomembrane anchoring system to create a stable surface for thin-film photovoltaic solar panels, directly adhered to the geomembrane, to create an integrated final landfill cover system, allowing an owner of a solid-waste disposal facility or a mine tailings storage facility (TSF) to cap it with a system that generates clean and renewable electrical power.

The exposed geomembrane solar cap at Hickory Ridge was designed by HDR for hot and cold conditions, and wind and rain storms associated with the Atlanta area.

The grading of the landfill met the existing permitted elevations that took advantage of the site’s good drainage characteristics, and its large open area, to create an ideal location for the attachment of flexible laminate solar panels. Although these solar panels were initially developed for rooftop uses, they also can be designed into a landfill exposed geomembrane cap system with remarkable results.

This Hickory Ridge Landfill solar-energy cover uses approximately 7 000 solar panels to convert sunlight into more than 1 MW of renewable electricity. HDR provided the design and permit application of the Hickory Ridge solar-energy cover in 2009 that made it the world’s largest exposed geomembrane solar cap and the first of its kind to be approved as a final cover landfill closure system in Georgia.

As well as producing commercial-scale quantities of clean solar energy, the exposed

geomembrane solar cap design is an improvement over soil/grass and composite covers because it: • minimises cap erosion and dust • promotes positive drainage with silt-free stormwater runoff • cuts off any further leachate generation • reduces landfill cap maintenance • accommodates settling and subsidence.

This type of alternative closure cap was approved and has since been a suggested alternative approach, by the United States Environmental Protection Agency (US EPA) because it promotes capping areas of landfills that have achieved their final permitted grades and thereby improves the environmental status of landfills and other waste storage and disposal facilities. 'These caps reduce dust emissions, landfill gas surface emissions and cut off stormwater intrusion into the waste mass from becoming leachate percolating to the bottom of the landfill,' remarked US EPA Region 4 officials when they visited site.

Solar energy caps can also provide a revenue stream with the following

potential benefits: • long-term maintenance cost savings • solar incentives and rebates for project construction • solar-renewable-energy credits • sale of renewable power • availability of on-site electricity to avoid electricity bills and promote energy independence • positive image of sustainability and energy independence.

The Hickory Ridge solar-energy cover and others like it accomplish more than many more complicated energy systems: they provide cost-efficient and environmentally protective containment of materials while generating renewable solar electricity. The Hickory Ridge solar-energy cover is a great example of built-in and affordable opportunities for a truly beneficial secondary use that can be used as a model of future caps for TSFs and landfill closures for the world’s tailings-storage and waste-disposal facilities.

The Hickor y Ridge Landfill closure FIGURE 1 Tessman Road solar-energy cap

RéSource May 2014 – 9

Landfill

represents a milestone in the solid waste industry because it replaces the US EPAprescribed Subtitle D closure cap with an alternative cap system that provides a number of environmental and economical benefits. The transformation of a landfill that has reached its design capacity into a commercial-sized solar energy generation facility is an extension of the ‘solar moment' in the solid waste industry realised in 2009 with HDR’s design of Republic Services' Tessman Road Landfill Solar Energy Cover in San Antonio, Texas. The Tessman Road solar-energy cover project represented the first design and installation of a solar landfill capping system, integrating innovative exposed geomembrane cap design and modern photovoltaic technology with a landfill closure.

The solar-energy cover system closure can harvest solar energy while safely capping a landfill or TSF in accordance with the regulatory requirements. Building solar parks while capping landfills and TSFs provide an ideal secondary use for property with limited potential for redevelopment, and create a beneficial reuse that can provide an immediate environmental, social and economic value to the owners and neighbours -- a classic ‘lemons into lemonade' solution.

Designed with long-term performance in mind HDR engineered the exposed geomembrane solar cap to meet all US EPA landfill closure requirements while providing a stable surface on which to mount an array of thin, flexible photovoltaic laminates for large-scale FIGURE 2 An aerial view of the exposed geomembrane solar cap on Hickory Ridge Landfill

* ABOUT THE AUTHORS Mark Roberts is a Senior Project manager for HDR and Sipho Dube is the managing director for Landfill Consult.

They have established a partnership committed to delivering world-class and innovative waste management and environmental engineering projects to South Africa.

renewable electricity generation.

For the geomembrane portion of the system, HDR used a 60 mm reinforced geomembrane with a long history of successful application and performance characteristics, including UV resistance, seam strength, chemical and puncture resistance and interface friction, and a 30-year warranty.

The flexible solar panels selected for this application proved ideal because they are lightweight, require no bracing and thereby don’t add any point load sources to the surface of the settling waste mass.

Applied directly to the geomembrane atop the landfill, the laminated photovoltaic panels are less than a quarter-inch thick and can generate electricity in high and low light and under low and high temperatures, yearround. The system is designed so the solar panels can be easily replaced at the end of their useable life (with a 20-year standard product guarantee to meet 90% of their rated capacity).

Engineered environmental controls The Hickory Ridge Landfill solar-energy cover system represents a different and more effective design than the typical and traditional closure systems that utilise soils to cover geomembranes. This exposed geomembrane cap design is

engineered to outperform traditional landfill closure designs with greater environmental protection at less than half the material cost of a conventional US EPA Subtitle D-prescribed landfill closure. The figure below illustrates the difference between the cross-section of a solar-energy cover and a traditionally prescribed final-cover system. When comparing a solar-energy cover to a traditional closure, what appears to be a missing component (no topsoil or vegetative support layers above the geomembrane) is actually a design strength, as it is anchored into the material as opposed to draped and ballasted.

Landfills and TSFs are well suited for solar-energy covers because they are graded to achieve positive drainage and the sideslopes are angled in a way to achieve high efficiency of sunlight conversion into renewable energy without the necessity of any bracing and/or angled racking systems. The solar-energy cover can incorporate as many solar panels as the owner chooses and is easily expandable to incorporate more panels without additional detailed design or permitting.

Implementation of sustainability More than just a win-win situation, the solarenergy cover installed for closure at the

10 – RéSource May 2014

)4 0!93 4/ +./7 Landfill

Hickory Ridge Landfill is a win-win-win. Solar-capped landfill closures provide a triple play of benefits that includes generating renewable energy, creating a revenue stream and eliminating erosion and dust.

The Hickory Ridge Landfill Solar Energy Cover project was awarded a $2 million (R21 million) grant obtained through President Obama’s federal stimulus programme.The grant was announced by the Georgia Environmental Facilities Authority as one of the energyrelated projects funded by the American Recovery and Reinvestment Act. The Hickory Ridge solar-energy cover is an example of the type of projects funded to help encourage energy savings and adopt renewable energy. HDR also emphasises the value of solar energy covers as outstanding examples of sustainable investment with a high benefit-to-cost ratio.

Solar energy from a landfill solar park like Hickory Ridge serves as a positive visual reminder of the beneficial reuse of a closed, inactive or decommissioned industrial area. Perhaps one day, solar panels atop closed landfills and TSFs will be as ubiquitous as wind turbines, and provide a new iconic image of alternative ways to power the world.

Solar-energy covers simply make sense, both at current cost and future cost-benefit comparisons with traditional systems with worldwide application potential. The Hickory Ridge solar-energy cover project is an outstanding example of sustainable investment, with a high benefit to cost ratio, relatively low risk and great potential to increase energy efficiency and produce green jobs.

From a purely economic perspective, a solar-energy cover system compared with the cost of a Subtitle D prescribed closure system provides an economic benefit strictly on electricity sales, in less time than the warranty period of the system of 20 years. It can be much less. There are a number other forms of credits and renewable energy incentives that may substantially increase the economic benefits and accelerate the break-even timeline. The economic benefit of the solar-energy cover continues to increase the longer it is in place.

FIGURE 3 Geomembrane solar cap vs Subtitle D cap

ÂĽ #ATERPILLAR !LL 2IGHTS 2ESERVED #!4 #!4%20),,!2 "5),4 &/2 )4 THEIR respective logos, “Caterpillar Yellow,â€? the “Power Edgeâ€?trade dress as well as corporate and product identity used herein, are trademarks of Caterpillar and may not be used without permission.

RÊSource May 2014 – 11

Landfill

Solid waste compacting Mangaung solid waste impressed with new Bomag waste compactors

A

lthough the Mangaung Metropolitan Municipality (MMM) is only the sixth largest in South Africa, this does not mean that its citizens generate less solid waste. As with all well-managed solid waste sites, processing this waste in an efficient and environmentally friendly manner is key.

The MMM has three large solid waste sites with the one in the south of the city the largest, at 117.25 hectares. The city’s northern landfill site is smaller at just over 39 hectares and then the Botshabelo site, some 55 km east of Bloemfontein, is 24 hectares in size.

‘We have a fleet of 26 compaction vehicles collecting waste in the city but, due to a low mechanical availability, they are not always all available and we then make use of contractors,’ says Glory Twala, the general manager for solid waste management at the MMM. ‘Between the two main solid landfill sites in Bloemfontein, we handle more than 16 000 tonnes of waste a month and we were pleased when, in 2013, our fleet management division bought three new, dedicated Bomag BC572 RB-2 waste compactors.’

These specialised machines were bought to replace an ageing and assorted fleet of converted front-end loaders that were nearing the end of their economical lifespans.

Working through normal tender procedures as set out by the MMM’s supply chain

LEFT General manager for solid waste management at the Mangaung Metropolitan Municipality, Glory Twala (left), discusses landfill sites with Lawrence Jacobs, manager for the municipality’s three landfill sites

12 – RéSource May 2014

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Landfill

management, specific criteria were set for the waste compactors and these, according to Twala, were more than adequately met by the Bomag BC572 RB-2 waste compactors.

We ask Izak van Niekerk, Bell Equipment’s general manager: Bomag and Finlay, why this specific machine was recommended.

‘Our public sector team consulted with me and Christophe Gaignerot, Bomag Southern Africa’s sales manager, to compile a suitable solution for the MMM’s requirements,’ he says. ‘The Bomag BC572 RB-2 was selected for this site according to the tonnage of waste to be spread and compacted during a working shift and at peak hour. This compactor is capable of handling 300 t/h during peak time and generally averages over 500 t/8h in a shift.’

Managing and compacting waste does not merely involve driving over it with something heavy. A kneading method, delivering predetermined compaction rates, is called for and, here, the Bomag BC572 RB-2 does the job more than adequately.

‘The push blade is a massive 3.8 m wide and its 11.6 m³ capacity can spread a large quantity of waste. The upper part of the blade is gridded to allow the operator to see through,’ says Christophe Gaigernot, Bomag Southern Africa sales manager. ‘A high compaction performance is achieved through the heavy weight of the machine at 29 tonnes,

and the wide steel wheels of 1 125 mm.

The oscillation and articulating joint ensure the ground contact of all four wheels for the best traction and compaction.’

According to Gaignerot, the wheels, with their trapezoidal rings and cleats, are designed to give an optimised crushing and kneading effect on the waste, as the front and rear wheels’ tracks have an offset to increase this kneading effect.

The machine, further, is fitted with scrapers to keep the wheels clean for the best compaction performance.

‘Bomag refuse compactors are purposely designed and built to work in the harshest waste sites where industrial and construction wastes are dumped with domestic wastes,’ Gaignerot adds. ‘The base frame is completely closed, with no exposed mechanisms, for less maintenance and a better lifetime, resulting in the expected lifetime, without major overhaul, to be around 15 000 hours.’

Although conceding that while their three Bomag BC572 RB-2 waste compactors are still relatively new, their high mechanical availability in excess of 95% and lower-than-expected fuel consumption have impressed Lawrence Jacobs, the MMM manager for all three landfill sites. ‘These sixcylinder Deutz TCD 2015 V06 engines just seem to purr along,’ he says. ‘We have also

ABOVE One of three Bomag BC572 RB-2 waste compactors that were bought by the Mangaung Metropolitan Municipality to replace an ageing and assorted fleet of converted front-end loaders

been struck by how easy it has been for our operators to make the transition from traditional front-end loaders that are steered with a steering wheel, to the complete joystick operation of the Bomag waste compactors.’

Jacobs is enthusiastic when he talks about the ergonomically designed cab with its joystick control, and all switches and warning lights being within easy reach and clearly in the operator’s field of vision. ‘The operator’s cabin is spacious, ergonomic and designed for fatigue-free work,’ he smiles. ‘It is isolated from vibration and sound for increased comfort and is fitted with an efficient airconditioning unit with filtration against odour ingress. The seat is also air-cushioned for higher comfort.’

‘We’ve been very impressed with the way our new Bomag BC572 RB-2 waste compactors are working and we also have use of new Bell L1506E front-end loaders that unload earth to cover the layers of the landfill site,’ Glory Twala says. ‘We’re confident that this new equipment will add value in our mission to make good on our undertaking of effective service delivery to the citizens of our municipality.’

RéSource May 2014 – 13

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WASTE TRUCKS

Landfill

The ins and outs of waste compaction T

he question is: What is your rear-loading waste compactor (REL) doing?

In Table 1, we take a look at the average eight-hour working day of a 20 m³ REL on a domestic waste collection round.

This REL makes two trips per working day to the landfill, being a total of 40 m³ in waste.

The example in Table 1 reflects the following: • Only the driver in Table 1 works a full eighthour day.

• The staff, consisting of four to five collection crew, work a little more than half the day.

All the RELs start their work day at the same time, all empty.

This results in most of the REL collection fleet having to discharge the first load, as well as the second load, to the landfill at the same time, resulting in a high traffic volume at the landfill site.

Furthermore, every time the REL visits the landfill site, there is a great risk of obtaining damage to the unit, mainly to the tyres and drive train.

The answer to the question above is that the REL spends about half the day collecting waste.

The solution If there is no need for your waste collection unit to visit the landfill site, it will: TABLE 2 • Allow you to collect waste at night, even if the landfill is closed.

Day shift loads • Reduce the risk of Night shift loads truck damage.

• Give you an extra Monday two hours and fifteen Tuesday minutes per day to collect waste.

Wednesday Let’s take a look at this action of ‘not taking your Thursday collection truck to landfill’ Friday in Table 2.

A proven method to obtain more full loads clear undertaking of their commitment to the per day with the result of saving in fleet size South African market.

A very large stock holding, factory-trained and cost, are all included in the Translift staff, as well as two workshops in South demount body system.

The Translift system has proved itself in Africa, all prove that Translift does support many waste collection fleets throughout the its products: • 24-hour product support world, including South Africa.

The Translift compactor has a 20 m³ • long-term full maintenance contracts. demount container body, which is transport- Further to your reading and/or research, suggested material of interest to you: ed to the landfill site with a hook lift.

One hook lift truck will be able to service • Municipal waste management – good practices, CSIR ISBN no. 978-0-7988-5596, five to eight compactor bodies a day.

March 2011.

Full compactor bodies are swapped for empty bodies at any hard surface near the • ‘Twice as good' in Waste Management World, Vol 12, Issue 2. collection area.

This action is used for night-time collec- • www.translift.nl tion as well, where the full TABLE 1 bodies are then demounted Rear-loading waste compactor (capacity 20 m3) only to be moved to the The normal working day of a waste compactor truck starts at 07:00 landfill the following day, and ends at 15:00, giving a total of eight hours or 480 minutes after the landfill reopens Activity Depot time Collection Landfill time for business. (minutes) time (minutes) (minutes) The Translift compactor Travel to collection area 35 has two container lifts – Collecting waste 138 one on the left side and one Travel to landfill 35 on the right side. These lifts Discharge first load 15 can work: Return to collection area 35 • 4 x 240 ℓ bins at a time Collecting waste 137 • 2 x 1 100 ℓ bins at a time Travel to landfill 35 • normal bag waste.

Discharge second load 15 Translift runs their own Travel to depot 35 operation in South Africa, a 70 275 135

REL loads per day 2 0

Side-loading demount body waste compactor (capacity: 20 m3) Side-loader Side-loader loads per day loads per day 3 3 0 2

2 2

3 3

2

4

2 2

Total 10 loads

2 3

5 5 Total 10 loads Extra 15 loads

Total 10 loads

5 5 5

Side-loader loads per day 3 3 6 4

Total 10 loads

8

Extra 15 loads

6 6

Extra 20 loads

RéSource May 2014 – 15

Hot seat

KAYTECH AND PETCO

Serving the recycling market Maryke Foulds speaks to Cheri Scholtz of PETCO and Chris Els of Kaytech about ten years of recycling cooperation.

Please give me some background on Kaytech and its involvement in the PET recycling industry Kaytech (originally Noel Hunt Geofabrics), part of the Kaymac Group, is the pioneering entity that introduced Bidim geotextiles to the South African construction market with the first recorded installation in 1971. Kaytech continued to grow this market to a point where local production of this unique product became more attractive. The commissioning of Kaymac’s own Bidim production plant, situated in Atlantis, Cape Town, was completed at the end of 1978. Kaymac started with exploratory work introducing recycled polyester into its production process around 1984. Original sources of recycled polyester were from soft drink bottle production and reclaimed used soft drink

16 – RéSource May 2014

bottles. Since 2001, all Bidim production has been from 100% recycled products, yielding a stronger product than that obtainable from virgin textilegrade PET polymer.

What is the current status of PET recycling in South Africa?

It is estimated that South Africa produced 1.37 million tonnes of virgin plastic in 2013, with just over half being used in the packaging sector; 21% of this was recovered and 19.9% was recycled. Of the packaging market, the PET market size was 26%. Close on 70% of this was used in the beverage sector, with the remaining markets being the sheet/tray, personal care, food, household and edible oil sectors – PETCO achieved a recycling rate of 48% of post- consumer beverage PET in 2013 – that is, a collection of 59 691 tonnes. This growth

in recycling figures, for the 9th consecutive year, would not have been possible without the continued voluntary financial support of PETCO’s shareholder members who enable the organisation to support the entire value chain and entrench PETCO as a successful model for voluntary EPR in South Africa. South Africa is on track and is working towards recycling 70% of post-consumer beverage PET by 2022.

Currently, PET is recycled into three end-use products for the local and export markets: • Bottle-2-Fibre/filament: Polyester staple fibre/ filament, made from PET recyclate, is used in apparel, home textiles, automotive and industrial end-use applications.

• Bottle-2-Foodgrade: rPET is blended with virgin material for the production of new PET

ABOVE Bidim, in its final form, is presented much like a rolled carpet

containers for both food and non-food products.

• Bottle-2-Bottle: Capacity is currently being installed for expansion into carbonated soft drink grade approved Bottle-2-Bottle resin. This is where the future growth in South Africa will be.

Is this a growing market? If so, why? The largest end-use market for post-consumer PET bottles in South Africa is currently the polyester staple fibre market, which is close to saturation. Bidim fits into the value chain in that its application and process is more tolerant to bottle types not currently considered desirable for the new bottle-to-bottle process, without compromising product integrity. Geotextile

Geotextiles offer a better alternative to conventional construction materials like sand and stone aggregate in landfills

Hot seat

markets have shown a steady growth over the last 10 years, peaking around the time leading up to the 2010 FIFA World Cup. Currently mega projects like the Medupi and Kusile power stations and the infrastructure to support them (coal stockyards and discard areas and so on) are requiring significant lining systems in which geotextiles play a vital role.

Mining is a significant contributor to geotextile usage; domestic and hazardous waste landfills, however, continue to generate the major demand for geosynthetic lining system designs incorporating geotextiles to ensure that the government-legislated minimum requirements are strictly adhered to. rPET is also blended with virgin material for the production of new PET containers for both food and non-food products. This is true closed-loop recycling. Capacity is currently being installed for expansion into carbonated soft drink grade approved Bottle-2-Bottle resin.

Please elaborate on Kaytech’s recycling initiative and how the recycled product is reused to manufacture product Bidim geotextile is produced from sorted, granulated and then washed polyester (PET) bottle flakes. The processed flake is supplied by both large formal, and smaller

entrepreneurial, business, some of which were started some years back, specifically to supply the demand created

by Bidim production. The Bidim production process consists of selective polymer blending, crystallisation, drying, pigmentation, extrusion, fibreand batt-forming and finally, consolidation via a needlepunching process into a fabric, finally presented much like a rolled carpet.

Please explain the use of PET recycled material in the geotextiles industry and how this is a greening initiative PET food-grade polymer is manufactured to a high standard and behaves in a predictable way through its primary processing into bottles.

This characteristic allows for the recycled polymer to be used in strictly controlled applications, like those for geotextiles.

Geotextiles, with a much extended useful life, offer a better alternative to conventional construction materials like sand and stone aggregate in landfills, thereby reducing the CO2 emissions and reducing the carbon footprint. The use of geotextiles in place of thicker sand or other natural material layers thus also helps improve the effective volume available for waste disposal, as well as the associated replacement and land-filling costs.

Please explain the process of recycling of PET bottles. What are the technical aspects and challenges of this? Discarded post-consumer PET bottles are collected (principally by informal collectors), baled and delivered to the recycler. At present, PET fetches one of the highest prices at recycler, with approximately 33 bottles making up one kilogram of PET. Within the recycling plant, bottle tops are removed and the bottles are inspected and sorted according to colour and material. The sorted bottles are washed and then conveyed to a granulator, where they are chopped into flakes before being screened. These flakes are then washed, dried and conveyed to an extruder where the material is turned into pellets. The finished product takes the form of small, clear pellets which are supplied to end-users for the production of other items.

The proprietary Bidim production process varies somewhat from staple fibre and bottle-to-bottle recycle processes. The Bidim process is unique in that it utilises recycled bottle material directly, not needing conversion into virgin mimicking pellets first.

The ability to directly use the chopped-up bottle material makes the recycling process more energy efficient, reducing the overall carbon footprint of our product. Limiting the number of extrusion passes, compared to more traditional fibre recycling processes, aids in the retention of those desirable polymer properties.

What is the relationship between Kaytech and PETCO and what is your vision for this partnership going forward? Kaytech, as a contracted recycler, forms part of PETCO’s recycling drive by creating demand for post-consumer recycled PET.

IN A

NUTSHELL N UT P ost-consumer PET recycling in SA, 2013, in a nutshell: • Tonnage collected: 59 691 tonnes • 18.7% growth on 2012 • Approximately 1.9 billion PET bottles recycled • Continued saving of 89 500 tonnes of carbon and 370 000 m3 landfill space • Creation of 41 000 sustainable livelihoods

Bidim demand for recycled PET polymer offers an alternative to the land filling of this useful polymer. Bidim continues to offer an economically viable, long-term outlet for existing and future recycling initiatives.

Amongst other things, PETCO supports projects that focus on increasing the economically viable collection and recycling of post-consumer PET. We provide financial assistance to large-scale projects that currently have an end-use product within their valuechains and subsidise recyclers for every ton of PET that they recycle.

In order to sustain and grow PET bottle collection, consistent demand for postconsumer PET is required.

PETCO could not achieve its collection targets without the support of our collectors and contracted service providers, like Kaytech. Our other contracted recyclers are Extrupet, who produce polyester staple fibre and bottle-to-food grade rPET; and Sen Li Da who produce polyester staple fibre. Later this year, a milestone will be achieved – one of PETCO’s contracted recyclers will be producing CSD grade (Bottle-2-Bottle) recycled resin for the industry.

This would not have happened without the economic support of PETCO.

RéSource May 2014 – 17

Recycling

Post-consumer PET recycling

By Lisa Parkers

PETCO, the industry body for recycling post-consumer polyethylene terephthalate (PET), reports that since its inception in 2004, the organisation has provided millions of rands worth of financial support to the post-consumer PET recycling value chain.

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hey have created an estimated 433 350 income opportunities for collectors, helped to establish 364 plastic recovery stations throughout South Africa, spearheaded the introduction of bottle-tobottle recycling (the manufacture of top-quality PET pellets from used bottles) and diverted 630 380 tonnes of post-consumer PET beverage bottles from landfill to useful purposes.

This is the legacy of a decade of targeted recycling, entrenching PETCO as a successful model for voluntary EPR in South Africa.

2013 results for post-consumer PET recycling in South Africa, show that PETCO achieved a recycling rate of 48% of postconsumer beverage PET – above its 46% target. Growth in tonnage collected reached 59 691 tonnes, an impressive 18.6% growth on 2012’s collection of 50 274 tonnes. It is testimony to the vision of the industry that PETCO is enjoying such success in a relatively short time and is now almost recycling as much material as

18 – RéSource May 2014

is being landfilled, notes Cheri Scholtz, CEO of PETCO. This growth in recycling figures would not have been possible without the continued financial commitment of PETCO’s shareholder members, who enable the organisation to support the entire value chain by paying a voluntary levy on every tonne of raw material purchased. Likewise, industry, government and community collaboration, has maximised the inherent environmental, resource efficiency and socio-economic benefits that PET recycling offers.

In addition to improved recycling rates, 2013 saw an expansion in its contracted recycler capacity with the establishment of two additional wash plants and an integrated flake-to-fibre line in the country. There has also been an acceleration of infrastructure development, such as drop-off centres and recycling initiatives and an increase in visible recycling projects, training and litter awareness projects, notes Scholtz.

The outlook for post-consumer PET recycling in 2014 2014 will be a challenging year, with the world teetering on the edge of a global recession, rising energy and petroleum prices and an increased PET resin market size. PETCO has targeted a collection rate of 48% for this year, which equates to 64 000 tonnes. The market is estimated to grow by seven to eight per cent from last year, so this is no mean feat. 2015 sees a target of 50% of all beverage bottles recycled, representing one in ever y two bottles produced.

PETCO is optimistic about the sustained demand for recycled PET, which is currently used in both the polyester fibre and packaging markets. ‘Over the past 10 years we have seen remarkable growth in the production of recycled PET fibre, negating the need to impor t cer tain kinds of fibre completely,' says Scholtz. ‘With us progressively having saturated the fibre market, we look to new end uses for recycled PET,' she adds. In 2013, there was an increase in the market uptake of PET recycling in bottle-to-foodgrade applications, like juice bottles and packaging, a true closed-loop system. Not only was material sold below the price of virgin material, thus saving money for the PET industr y

Recycling

alive and well PETCO is optimistic about the sustained demand for recycled PET which is currently used in both the polyester fibre and packaging markets (and consumers), but with the recent lightweighting of PET bottles over the past few years (by almost 30%), there has also been a reduction in virgin material required for the production of PET packaging. PETCO is now playing a major role in introducing bottleto-bottle recycling later this year, with contracted recyclers now being able to offer approved recycled resin for use in carbonated soft drink bottles.

This widens the scope of end-market applications for recycled PET and thus fuels our collection drive and contribution to the green economy.

Having already collected the lowhanging fruit, PETCO needs to significantly increase collection volumes and gain access to clean, quality PET to provide feedstock for additional plants and this new end-use. Scholtz adds that there is a need for more innovation in the industr y’s approach to bottle collections and infrastructure roll-out, especially when it comes to the formation of public-private par tnerships. PETCO also sees opportunities in fur ther end-market and FIGURE 1 Growth of PET plastic beverage bottle recycling rates in South Africa

product-development design for recycling and manufacturing innovation.

Post-consumer waste recycling stands at the nexus point of several critical issues of our time, including business competition for increasingly scarce resources, shrinking municipal budgets, climate change and unemployment. Developing the recycling economy presents the oppor tunity to create win-win innovations in the relationship between government, NGOs and business, and truly develop the green economy. ‘In par ticular the waste sector offers oppor tunities for communitybased, labor-intensive job-creation initiatives,' concludes Scholtz. ‘Last year 41 000 income oppor tunities were generated in the PET plastic recycling sector alone and we look for ward to playing a more meaningful role in facilitating this growth, working towards a greener, less wasteful, more sustainable future.'

For more information see www.petco.co.za or keep your finger on the PET Pulse – read the PETCO blog or visit its Facebook page: PETCO-1isPET.

50% 45% 40% 35% 30% 25% 20% 15% 10% 5% 0% 2005 2006 2007 2008 2009 2010 2011 2012 2013

RéSource May 2014 – 19

Nuclear waste

Monitoring nuclear waste legacy ponds Following a rigorous assessment period, EXO water quality monitoring sondes from Xylem Analytics are being deployed in what is arguably one of the most hostile environments imaginable – nuclear waste legacy storage ponds at the Sellafield nuclear reprocessing site in Cumbria, UK.

O

ne of the major challenges facing Sellafield Ltd is the safe decommissioning of the First Generation Magnox Storage Pond (FGMSP), a nuclear fuel storage facility that was originally built in the 1950s and 1960s as part of the UK’s expanding nuclear programme to receive, store and cool irradiated Magnox fuel prior to reprocessing.

In the 1970s a lengthy shutdown at the Magnox reprocessing plant, combined with increased throughput of fuel due to electricity shortages, saw spent fuel stored in the pond for longer than the designed period, which led to increased fuel corrosion and radiation levels.

Over the years, the pond has accumulated significant quantities of waste materials, sludges from corrosion of fuel cladding, skips of fuel, and fuel fragments and other debris, which have blown

into the pond. Standing above ground, this 5 m deep open pond holding some 14 000 cubic metres of contaminated water (approximately the size of two Olympic swimming pools) is considered a decommissioning priority. To assist with future retrievals, a detailed knowledge of the facility’s inventory through visual inspection of the pond is needed.

Despite high levels of radioactivity, this open pond appears to intermittently bloom with a range of microorganisms that cloud the water, reducing visibility and hampering inspection and retrieval operations.

Sellafield is the company responsible for safely delivering decommissioning, reprocessing and nuclear waste management activities on behalf of the Nuclear Decommissioning Authority (NDA), and a project team led by Xavier Poteau has the specific responsibility of transferring monitoring technologies to the FGMSP pond.

Water passing through the pond reaches the Sellafield Ion Exchange Effluent Plant (SIXEP), which removes radioactivity from liquid feeds from a number of plants across the Sellafield site. The plant settles out and filters solids using a carbonation process to neutralise the alkaline pond water and then employs ion exchange to remove radionuclides.

Why monitor?

Water samples are routinely collected from the pond for laboratory analysis, and analytical data is reported to the Environment Agency and the NDA. In addition to this regulatory requirement, water quality data is also required to inform efficient operation of SIXEP and to ensure that legacy fuel is stored in optimal conditions. For example, the water is caustic-dosed to maintain a pH of around 11.5, which reduces the speed of nuclear-fuel degradation.

Water monitoring challenges As a result of physical restrictions, it has only been possible to take water samples from specific locations around the edge of the pond and, being radioactive, routine samples have to be limited to about 100 ml to be within laboratories guidelines.

Sampling is also an arduous, time-consuming process; two people have to be involved and each sampler has to wear a PVC suit and facemask, two pairs of PVC waterproof gloves and a pair of Kevlar gloves to ensure that the gloves are not accidentally punctured. The samplers are also only allowed to be close to the pond for a limited time.

Instrumentation might appear to be the TOP LEFT The Xylem EXO water quality sondes LEFT Over the years the pond has accumulated significant quantities of waste materials

20 – RéSource May 2014

Nuclear waste

RIGHT The instruments are lightweight and rugged with internal batteries and datalogging capabilities

obvious solution but, again, there are several challenges, not least of which is that gamma spectrum analysis has to be conducted on a sample in a lab. In addition, electrical instruments often fail in a radioactive environment, so the general assumption is that they will do so, unless proven otherwise. Continuous monitoring probes, similar to those employed by the water industry, are not feasible because of the wiring that would be required. However, portable instruments offer the potential to reduce the volume and frequency of water sampling.

Trials with EXO sondes The EXO2 sondes are multiparameter sixport water quality monitors that have been developed for remote, long-term monitoring applications. Employed globally by regulatory authorities, researchers, industrial companies and those responsible for the protection of water resources, the EXO sondes are the result of many years of development and feedback from thousands of users all over the world. As a result, these instruments are lightweight and rugged, with internal batteries and datalogging capabilities for long-term monitoring applications. The EXO sondes operate on extremely low power and incorporate a range of features that minimise maintenance requirements and avoid biofouling. For example: wet mateable connectors resist corrosion; components are isolated to prevent short-circuits; welded housings and double O-rings prevent leaks; and high-impact plastic and titanium resist impact damage.

The ‘smart’ EXO sensors are easily interchangeable and users are able to select the sensors that best meet their needs. The FGMSP project team, for example, uses sensors for pH, temperature, conductivity, turbidity, fDOM (fluorescent dissolved organic matter – a surrogate for coloured DOM), blue-green algae and chlorophyll.

Initially, the FGMSP project team trialled an extended deployment version of the YSI 6600 multiparameter water quality monitoring sonde – a predecessor of the EXO. ‘This enabled us to assess the quality of the YSI sensors and demonstrate that they were

able to operate well in a radioactive environment,' comments technical specialist Marcus Coupe, adding: ‘The launch of the EXO was of great interest to us because, with Bluetooth communications and smart sensors that retain their calibration data, the EXO offered an opportunity to dramatically reduce time spent at the pond.

‘The snap-on probes are calibrated in the laboratory and can be quickly and simply swapped with those that have been deployed on an EXO sonde. This means that the main part of the sonde can be left onsite while the sensors are quickly swapped, and the Bluetooth comms enable us to collect 18 600 sets of data in less than 20 minutes.'

Commenting further on the success of the EXO trials, Xavier Poteau says: ‘It has been common experience in the nuclear industry to have to apply significant adaptations to electrical equipment, so that it is able to function correctly in a radioactive environment, and this can incur a heavy cost and time penalty. However, the EXO sondes have performed very well "off the shelf", which is a sign of good design.'

As part of their work with the EXO sondes, the FGMSP project team has deployed an EXO sonde with a submersible remotely operated vehicle (ROV). This enabled the team to monitor water quality at previously unachievable locations. ‘Any loss of visibility in the pond can potentially cause

Despite high levels of radioactivity, this open pond appears to intermittently bloom with a range of microorganisms that cloud the water

a significant risk to operations within the legacy ponds, as well as potentially slowing down future retrievals, so the ability to deploy an EXO with an ROV offers a valuable insight into understanding the challenge, and moves us from single-point sampling to a more 3D-like data stream,' adds Marcus Coupe.

Looking forward Neill Cornwell from Xylem Analytics has been involved with the trials at Sellafield from the start. He says: ‘A lot of hard work has gone into the process of demonstrating EXO’s suitability for deployment in the nuclear sector; not only has the equipment had to perform well in challenging conditions, but we have also had to demonstrate a high level of technical and service support.

‘Naturally, we are very pleased that the sondes have performed so well, and further instruments are now being deployed in other applications at the Sellafield site. For example, a slimmer version of the EXO, the EXO1, is being used to monitor the effluent distribution tanks because the only access is via narrow pipes and the EXO1 is ideal because its outer diameter is just 1.85 inches.'

The data from the FGMSP sondes compare favourably with the results of laboratory analysis, so Xavier Poteau believes ‘a high level of confidence is being established in the EXO data and this means that we will be able to reduce the amount of sampling that we undertake, which will save a great deal of time, hassle and money.

‘I strongly believe that our experience could be beneficial to the wider audience as well as the nuclear industry,' says Poteau.

RéSource May 2014 – 21

Sustainability

Sustainable solutions to emissions reduction The November 2013 United Nations Climate Change Conference identified human actions as the dominant cause of global warming, and highlighted an urgent need to reduce carbon emissions by at least 4% per annum in order to stay within the global carbon budget and prevent further harm to the environment.

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longside other major industrial sectors, the cement industry has a major obligation to contribute towards achieving this objective, particularly since the traditionally resource-intensive cementmaking process has resulted in this industry being ranked among the world’s top contributors of CO2 emissions.

Traditional cement-making consumes large quantities of materials such as limestone and other minerals. Although limestone is currently an abundant resource, it is non-renewable. At the same time, the energy required to power the kilns during clinker production is considerable, releasing high volumes of environmental emissions into the atmosphere.

22 – RéSource May 2014

Energy conservation has become a major focus area in the cement industry because, apart from ever-increasing energy costs, there are growing concerns over future energy availability. In South Africa, the thermal energy required to power the kilns is predominantly derived from coal (direct feed into the kiln) and electricity from the national grid. Every tonne of clinker produced from this process burns about 200 kg of coal.

Burning coal and other fuels produces undesirable greenhouse gases. Both this process and the calcination of limestone and clay materials release additional CO2 into the atmosphere. On average, the amount of CO2 released is almost 900 kg

AfriSam has invested significantly in research to develop and implement a CO2 measurement system on all its cement products

for every tonne of cement traditionally produced. Consequently, the cement industry worldwide is judged to be responsible for about 5% of the total carbon emissions into the atmosphere — among the highest industries in the world.

A typical cement plant presents several additional environmental challenges that must be managed at each stage of production, including dust emissions during blasting activities at quarries and at the cement factories, and the noise associated with these activities.

Sustainability

The drive to achieve economic Using 2000 as its base year, Energy conservation has growth is invariably associated with AfriSam has reduced its electrical become a major focus area in an increase in demand for cement energy consumption by 25% and its the cement industry because and other building materials, and this thermal energy consumption by 40%. there are growing concerns over has prompted the industry to find Another industry focus area is to new ways to overcome the associreduce the use of natural resources future energy availability ated environmental challenges and through the increased production so embrace the challenge of making of composite cements, sometimes cement production a sustainable process. fledged CO2-reduction programme and set called extended cements. This is evidence of This robust commitment has already led ambitious targets to reduce emissions asso- the industry’s growing willingness to make to the introduction of several cutting-edge ciated with its products, then took its first environmentally responsible decisions, and initiatives to mitigate environmental deg- major step towards CO2 reduction by launch- the resulting technological advancements radation, including technologies that make ing Project Green Cement that same year. have afforded cement manufacturers the Between 1990 and 2012, AfriSam reduced luxury of using alternative materials that it possible to reduce energy and resource its CO2 emissions per tonne of cement by possess cementitious properties and have consumption at all levels of production.

Green manufacturing calls for the preser- more than 30%. In 2009, the company a low carbon footprint. vation of natural resources and the reduc- introduced a world-first CO2 rating system on By definition, composite cements are protion and, wherever possible, elimination of all its cement bags, which means that the duced using a combination of clinker and harmful pollutants released into the atmos- carbon footprint of each AfriSam product is an increased proportion of pozzolanic minphere, especially CO2. There have been printed on every bag. eral components. Typically, these include widespread calls for ‘green’ cement with Advanced fuel- and energy-efficient by-products from other industries such as industry groups around the world adopting technologies play a major role in reduc- ground-granulated blast furnace slag from different sustainable cement initiatives. ing emissions and AfriSam was the first the steel manufacturing industry, pulverised These approaches range from pushing for South African company to install a much fly ash from coal-powered stations and silica the reform of international building codes, more energy-efficient vertical roller mill for fume, a by-product of silicon and ferrosilicon to finding alternative solutions to traditional grinding cement. alloy production. high-energy-intensive cements.

When AfriSam began Project Green For the past two decades, AfriSam has AfriSam signalled the authenticity of Cement, it installed state-of-the-art blenders conducted extensive research and developits environmental conscience more than that allowed the company blend cement with ment into the production of these advanced 15 years ago with the introduction of an mineral components (Mic). These Mic mixes cements, replacing the environmentally ahead-of-its-time environmental policy – result in a reduction in excess of 40% on unfriendly clinker and reducing its carbon long before ‘green’, ‘sustainability’ and electrical and thermal energy used in the footprint dramatically. AfriSam has poured ‘environmentally friendly’ became universal cement production process. The company considerable capital investment into upgradbuzzwords. In fact, it was the first cement has also invested in major energy-efficient ing its production facilities to produce producer in the world to develop an environ- upgrades of equipment at its production advanced composite cements, resulting in mental policy of this kind. plants and employed a team of process engi- a reduction in the clinker factor from a world AfriSam implements the drive towards neers to extract maximum energy efficiency average of about 90% to an average of ‘greening’ its industry at several different from each plant component. These meas- 60%, with reductions to as low as 35% for levels simultaneously, definitively position- ures, alongside behavioural, educational its particularly environmentally friendly Eco ing it as a South African market leader. In and staff-advocacy initiatives, have yielded Building Cement.

2000, the company implemented a fully significant energy savings.

Years of research at its Centre for Product Excellence have led to the composite cement technology that is today applied to all AfriSam products, including its innovative new 42.5 N All Purpose Cement, an advanced composite cement with active mineral components. This technology makes it possible to achieve greater concrete yield per bag of cement than before, without compromising performance. Interestingly, concrete made from the company’s 42.5 N cement continues to gain strength past the traditional 28-day cut-off, actually improving with time to achieve stronger structures.

AfriSam commissioned a vertical roller mill in 2009 to increase cement production capacity, decrease energy consumption and make its production processes more environmentally friendly

RéSource May 2014 – 23

African energy

Addressing the water-energy nexus

By Johannes Cilliers*

Since 1994, the United Nations has used World Water Day to focus the global consciousness on critical issues that have an impact on our most precious natural resource.

T

his year’s theme, ‘Water and Energy’, spotlights an issue that presents one of the greatest challenges to water conservation – the production of energy. According to the International Energy Agency, energy production alone accounts for some 15 per cent of the world’s total water withdrawal, which amounts to an estimated 580 billion cubic metres of freshwater per year. To put that number into context: global energy generation now consumes enough water per year to fill about 232 million olympic-sized swimming pools. In fact, thermoelectric power plants already account for over a third of freshwater withdrawal in the United States, where the volume is even more than the water used for agriculture, and in Europe.

There is no doubt that the water-energy nexus is real and of particular concern to water-scarce countries, such as South Africa. The fact of the matter is that most energy-generation technologies – including coal, nuclear and even concentrating

solar power (CSP) – consume tremendous amounts of water during operations, for processes such as fuel extraction, cooling and cleaning.

As our energy needs continue to grow, so too will our use of water to generate it.

The World Bank – which, earlier this year, launched its ‘Thirsty Energy’ initiative to highlight the water-energy nexus – predicts that while global energy consumption will increase by 35% by 2035, water consumption will increase by an alarming 85% during the same period of time.

Looked at in the context of energy demand in South Africa, where forecasts estimate a need for an additional 40 000 MW of electricity by 2025, the management of water resources will be critical to sustainably driving growth in the country’s generation capacity. Water is a finite resource and its use in electricity production should be managed through a diversified power-generation portfolio that minimises impacts on water usage.

Sunlight, on the other hand, is an abundant resource and, if effectively harnessed, can help mitigate some of the impact on our water resources.

Photovoltaic (PV) solar energy is one of only two electricity-generation technologies, the other being wind, with comparatively negligible water consumption. With only 20 litres of water consumed per MWh FIGURE 1 LEFT Volume of water used by different generation technologies to produce 1 MWh of power. Each drop represents 100 litres of water

24 – RéSource May 2014

of electricity produced, PV power plants consume as much as 152 times less water per MWh than wet-cooled CSP technologies, 17.5 times less than dry-cooled CSP, and 64 times less than coal plants. With over 8 000 MW of modules installed worldwide, First Solar alone helps displace over 14 billion litres of water per year.

On a life-cycle basis, PV also consumes less water than most other power-generation sources, including hydrocarbon-based technologies and those that use biofuels in the production process. With the smallest carbon footprint, lowest life-cycle water use, and fastest energy payback time in the industry, our thin-film PV modules provide a sustainable solution to climate change, water scarcity, and energy security. First Solar has further reduced life-cycle water use by reusing water during manufacturing, implementing advanced site preparation techniques to reduce dust generation during project construction, and using dry methods for module cleaning in dust-prone climates.

While a power portfolio that completely excludes thermal generation is an unrealistic expectation at this point in time, the reality is that water conservation needs to remain a priority. This year, as the world commemorates World Water Day, it will be important for the power-generation sector in South Africa, and around the world, to recognise the importance of minimising the use of water and to implement measures that address this very real challenge.

* ABOUT THE AUTHOR Johannes Cilliers is director of business development for subSaharan Africa at First Solar.

First Solar is a leading, global solar energy company.

African energy

More competitive electricity market required The spotlight was once again on South Africa’s power supply system when Eskom recently declared a power supply emergency, says Paul Fitzsimons of GIBB.

W

hile the state-owned power utility is better positioned to handle the constrained situation we face than it was in 2008, the country needs to consider a more market-driven demand side and competitive model to overcome some of its challenges.

That’s the word from GIBB’s power and energy sector general manager, Paul Fitzsimons, who says in mature markets different power generators sell electricity to a central independent buying office, which then sells the electricity on to energy wholesellers and retailers via distributors.

‘Whilst in many countries there are varying degrees of vertical integration, at the moment the majority of the entire process in South Africa – from generation and transmission to distribution to the end-user – is controlled by Eskom, but with municipalities and metros playing the role of retail distributors and on-sellers in many cases.

‘Although South Africa’s Renewable Energy Independent Power Producer Procurement Programme is a step in the right direction, independent power producers continue to bid electricity to the Department of Energy and transfer it back to Eskom, meaning the man in the street is not able to choose where he gets his electricity from.

‘In a "perfect" market there would be many generators competing to provide electricity to a single network operator. The electricity would then be transmitted to a number of distributors and, while the assets are geographically fixed, it is also possible to open operations of such systems to a form of competitive process through fixed-term management and operating contracts. While users may be stuck with a particular distribution network by virtue of geography, they would be able to buy electricity from anybody, and the introduction of competition in operations would naturally drive up performance and drive down cost,'says Fitzsimons.

This type of model was introduced in the users is actually a perfectly normal marketUK during the Thatcher years. ‘Competition driven response and a form of price hedging was forced into the system and an open bid- widely practiced in competitive commodity ding pool was established to buy electricity markets. In South Africa, industry reform from different generators. Different qualities has been on the agenda for some time. The of electricity (base load/peak-time) were Independent System and Market Operator priced differently. Prices were published and Bill, which proposes placing the operation there was a high degree of transparency. of the electricity grid in an independent, ‘Today, with electricity prices rocketing but state-owned entity, is a positive move in the UK, there has been a lot of dis- towards reform, but has been put on hold cussion around whether this model works twice this year,' says Fitzsimons. or not. Generating companies have been Eskom is the third largest electricity genaccused of creating internal middlemen erator worldwide. ‘This doesn’t make sense to sell electricity to themselves at inflated given the size of our population. The East prices, before on-selling it to the customer,' Coast of the US is probably ranked first and states Fitzsimons.

China second – which seems reasonable While the UK model is largely deregu- considering their large populations. SA is lated, Fitzsimons says a degree of regula- similar in size to the UK, but we probably tion is required to ensure the system is not have less people connected to the grid. abused. “Perhaps a good example is the While the UK has six major electricity generaUnited States where utilities are privately tors, three or four major generators would owned, but the sector remains highly regu- probably make sense for us.' lated. This is, of course, notwithstanding Fitzsimons explains that to avoid recurring spectacular failures such as the California energy crises, South Africa needs to serienergy crisis of 2000/2001,' he explains. ously consider deregulation of the market.

Importantly, proper demand-side manage- ‘Of course, the system can get highly compliment is where consumers are given the cated and relies on transparency and moral choice as to which supplier they buy their integrity, but it can have an enormously electricity from. This would be possible positive spin-off in the form of newly created in a market characterised by independ- businesses, a more secure power supply, ent transmission and distribution grids and increased foreign investment and – imporindependent power producers competing in tantly – more jobs for South Africans.' an open electricity market and characterised by the emergence of various market-driven demandmanagement solutions In a ‘perfect’ such as demand aggregamarket there would tors, energy brokers and be many generators similar risk and liquidity competing to provide measures. electricity to a single ‘While it has been critinetwork operator” Paul cised, the forward selling of bulk electricity for Fitzsimons, power and energy large-scale industrial sector general manager at GIBB

RéSource May 2014 – 25

Energy efficiency

Power savings are as important as power stations

By Andrew Etzinger

While the construction of Eskom’s three new power stations has attracted public interest, much less attention has been paid to a dedicated programme to reduce demand until the new power stations are on-line.

D

emand-side management, which became the broader Integrated Demand Management (IDM) programme, has been a key component of Eskom’s success in avoiding load-shedding since 2004.

It’s cheaper, quicker and more environmentally friendly to save a megawatt of power than to build a power station to generate one. Eskom’s new power stations are going to be essential to power South Africa’s expanding economy, although the first units of the Medupi and Kusile power stations – under construction in Limpopo and Mpumalanga, respectively – will take some time to come on-line. In the meantime, demand keeps rising over the long term.

This is why Eskom’s strategy is to increase capacity while at the same time helping customers to reduce demand through the implementation of energy-efficient measures and encouraging them to move consumption out of the peak evening and morning periods.

Since 2005, Eskom’s demand-side management programmes have yielded electricity savings totalling 3 587 MW. This is equivalent to the output of a ‘six pack' power station with six 600 MW generators.

The demand-management initiatives have both a short-term focus, the need for rapid energy-savings responses from customers, and energy-efficiency marketing programmes that aim to change customer behaviour immediately and over the longer term.

Changing customer behaviour is a crucial element, as South Africa is no longer a country with abundant or even excess electricity supply. At times, Eskom’s margin of supply over demand has been razor-thin, and it has only been the support of major customers, who have curtailed consumption in terms of agreements with Eskom, that has enabled Eskom to keep the lights on across the country.

The power supply is likely to remain tight for the next few years – margins will remain slim until 2015 – and the situation will not really ease until 2017 when most of Medupi’s units will be on-line and Kusile will have started supplying power to the grid. Even then, with the economy growing and industrial and residential demand rising, there won’t be a huge surplus of power.

Eskom has said repeatedly that it is committed to avoiding load-shedding and will do everything it can to keep the lights on, but that it cannot do it alone. That means that Eskom’s customers, residential, industrial and agricultural, will have to reduce electricity demand where possible and use electricity wisely by switching off unused lights and appliances, as well as the geyser and swimming pool pump during the evening peak period (between 17:00 to 21:00). Installing energy-efficient lamps and equipment also goes a long way in reducing consumption.

Eskom’s IDM team has been helping customers do just this for the past 10 years.

The IDM programme uses a combination of: • energy-efficiency measures that allow a specific function to be fulfilled as usual, while using less electricity (by installing more efficient equipment or process optimisation) • demand-management measures that shift electricity usage from a constrained or peak consumption period to a time when electricity is more readily available • demand-response measures that call on consumers to reduce consumption rapidly during critical periods to avoid blackouts.

The Medupi power station construction is underway

26 – RéSource May 2014

Energy efficiency

FIGURE 1 Peak demand graph

The role of and contribution from Integrated Demand Management Since its inception, the focus of the IDM programme has changed from a predominantly small-scale demonstration and awareness-creation initiative to a concerted drive to reduce energy consumption measurably, in light of the demand and supply inconsistencies.

During the period from 2004 to 2013, the IDM programme has saved the energy equivalent of a full year’s electricity consumption by the country’s capital, the City of Tshwane, in Gauteng.

Demand-side management interventions also successfully contributed to alleviating critical supply constraints during both 2006 and 2008.

In addition, Eskom has also made use of extensive mass rollouts for specific technologies such as compact fluorescent lamps, light emitting diode downlights, geyser blankets, shower heads and timers, among others. With the Residential Mass Rollout Programme, several of these technologies are being combined under one mass rollout programme.

South Africa’s Integrated Resource Plan, also known as IRP 2010, now incorporates a significant energy-efficiency and demandmanagement contribution to meet the forecasted electricity needs.

In the financial year ended March 2013, demand savings of more than 590 MW were verified, of which 103 MW was achieved in the commercial sector. The total was made up of savings of 376 MW in residential areas and municipalities, 105 MW in the industrial and mining sectors, 103 MW in the commercial sector and 7 MW in agriculture.

All consumers are going to have to contribute if Eskom is to keep the lights on over the next few years. Eskom has published energy-saving tips on its website www.eskom.co.za/idm, and the IDM team is ready to help with expert advice.

Below are some of the ways to save electricity.

Domestic users can adopt the following measures • Compact fluorescent lamps (CFL) – Compared to general-service incandescent lamps giving the same amount of visible light, CFLs use one-fifth to onethird the electric power, and last six to

fifteen times longer. A CFL has a higher purchase price than an incandescent lamp, but can save over five times its purchase price in electricity costs over the lamp’s lifetime.

• Light emitting diode (LED) downlights LEDs have many advantages over incandescent light sources, including lower energy consumption, a longer lifespan, improved physical robustness, smaller size and faster switching.

• Heat pumps and solar water-heating systems – A heat pump offers you a way to use electricity to heat water efficiently.

Where a geyser uses three units of electrical energy to produce three units of heat energy, a heat pump converts just one unit of electrical energy into three units of heat energy. Solar power is one of the most effective renewable energy sources available. By implementing it in water heating, we can target one of the most power-intensive household activities for maximum power-saving effect.

• Shower heads and timers – By simply changing a shower head to an energy efficient model, the consumer can save litres of water a day.

Commercial users can adopt the following measures • Policy – Companies can adopt a workplace energy-efficiency policy to encourage employees to use energy in a thoughtful manner.

• Turning off equipment – The computer may go to sleep, but it’s still sucking up energy. All computers should be turned off at the end of the day. Don’t leave equipment on standby mode. They continue to use up to 50% of normal power

consumption at no use.

• Printers – Where appropriate, use inkjet printers because they consume 90% less energy than laser printers.

• Control air conditioners – During the day, keep doors and windows closed while the aircon is on. Early mornings, open doors and windows to allow cool air to escape and warm air to flow in.

• In the kitchen – Most workplace coffee makers use more energy than one would think, especially those with a hot-water tank inside that remains hot 24/7. For those coffee makers, use a timer that will turn off the power overnight and turn it back on early in the morning so that the water is hot before the first coffee-drinker arrives.

• Light sensors – Install occupancy sensors instead of indoor light switches in offices. A preferred technology in recent years is a light switch that occupants turn on when desired, and the sensor will turn it off if the room is vacant.

• Outdoor lights – Ensure that parking lot and outdoor lights are turned on only when needed. Install or fine-tune occupancy sensors and/or photocells.

Replace outdoor lights with LEDs with good controls.

• Solar power – Investing in solar power systems in the business will help save electricity bills and help the environment.

Increased economic activity also results in a greater number of employment opportunities. Economic data indicate that for every hour without electricity supply, the country risks losing 235 jobs. This means it is in everybody’s interest to continue to save electricity.

RéSource May 2014 – 27

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Energy efficiency

Transforming SA’s waste into renewable power

By Tim Schweikert, President and CEO, GE South Africa

More than 90% of South Africa’s electricity is generated from the burning of coal. With governmental pressure mounting on companies and organisations to reduce their carbon footprint, renewable energy has quickly become the resource of choice to deliver growth for the country while protecting our environment.

L

ast November, the government took an important step forward by approving an additional 17 renewable energy projects, paving the way for a further R33.8 billion worth of investment that will add up to 1 470 MW of clean energy to South Africa’s national grid. Along with more commonly known technologies like wind and solar power, the announcement included approval for a waste-to-energy landfill gas project.

Though it may come as a surprise to some, landfills are one of the most fruitful resources for generating renewable power. Created during the decomposition of organic substances, landfill gas consists of methane, carbon dioxide and nitrogen.

The controlled collection and combustion of this problem gas is an indispensable step in the modern operation and re-cultivation of a landfill site. In addition, the high calorific value of landfill gas makes it a viable fuel for gas engines that can be effectively used for power generation.

For the past 25 years, GE Landfills are one of the most has been per fecting the fruitful resources for generating Jenbacher gas engine to renewable powers.” Tim Schweikert, transform various types of president and CEO, GE South Africa gas, including landfill gas, into renewable energy. GE currently has deployed more than 1 500 sewage) and gaseous (e.g. refinery gases) Jenbacher landfill gas systems, with a waste. The process of transforming this total electricity output of about 1 500 MW, waste into clean, renewable energy is throughout the world. called waste-to-energy (WTE) and GE is Importantly, the use of GE’s Jenbacher continuously innovating to drive efficiency engines is beneficial for the environment. and performance in this space.

With a class-leading efficiency of up to WTE is becoming an enabler to resolv47.8%, GE Jenbacher engines have an ing energy challenges in a cost-effective outstanding fuel economy and are parallel and sustainable way, globally. Europe, with the highest levels of environmenfor example, currently has more than tal performance. The engines reduce the 1 100 Jenbacherengines running on biogas. user’s reliance on coal for power genThe engines are also being used to convert eration while increasing reliability through coal-mine gas to electricity in Australia and distributed power. the Ukraine.

Ukraine GE’s Jenbacher technology can be applied Currently, South Africans generate around to several types of waste: from the semi60 to 70 million cubic metres of waste solid (e.g. thickened sludge from efflua year, ac according to the Department of Environmen ent treatment plants) to Environmental Affairs, and approximately liquid (e.g. domestic 95% of South So Africa’s waste is disposed of in landf landfill sites. This is an enormous, untapped reserve of renewable energy that can be transformed to power our homes and a businesses.

In 200 2007, the eThekwini Metropolitan Municip Municipality worked with GE to develop the first firs landfill gas-to-energy project in Sou South Africa. The project, which conver ts waste from three landfill sites in Durban (Mariannhill, La Mercy and Bi Bisasar Road), was identified by LEFT The Jen Jenbacher landfill gas system

RéSource May 2014 – 29

Energy efficiency

ABOVE Waste-to-energy plant in Durban ABOVE RIGHT The Jenbacher engine

KPMG as one of the world’s most exciting infrastructure projects.

The Bisasar Road landfill site is the busiest landfill in Africa, accepting 3 500 to 5 500 tonnes of municipal sewage waste daily, and will continue to accept waste for

another ten years. It has the potential to generate up to 10 MW of electricity through collection, combustion and landfill gas.

When combined with the landfill gas from the Mariannhill site, the project generates enough renewable energy to power 46 000 homes in South Africa.

The WTE process, powered by GE’s Jenbacher engines, not only provides

waste-collection entities an opportunity to contribute positively to the country’s sustainable energy supply, but also creates the potential for these entities to attain carbon credits. More municipalities, and indeed the country, can benefit from following in the footsteps of the eThekwini Metropolitan Municipality by adopting the WTE approach to power South Africa.

30 – RéSource May 2014

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Energy efficiency

Interesting insights shared at Coal Open Day Global and domestic energy needs give South Africa’s coal sector a long future, but there are a number of challenges the sector must meet if it is to make best use of its valuable carbon-based fuel resources.

T

his emerged at a Coal Open Day hosted by global consulting engineers and scientists, SRK Consulting SA, at their Johannesburg offices in Februar y. Various experts addressed media and clients on the prospects and challenges for coal.

The demand for coal globally remains strong, especially in the developing world, according to SRK principal engineer Andy McDonald, and par ticularly in countries like China and India. In China alone, where 70% of electricity generation is coal-fired, plans are afoot to almost double energy output from current levels of about 1 145 gigawatts to 2 000 gigawatts by 2025. The countr y burns some 3.8 billion tonnes of coal each year.

Demand in Africa is also high; the continent needs another 7 000 MW more electricity each year to keep up with its growth rate, says McDonald, and South Africa has 20% of its households still needing to be electrified.

To ser ve this need, coal exploration in African countries has been ongoing, says SRK principal coal geologist Lesley Jeffrey.

‘The projects ser ved by our Johannesburg office have been mainly in Southern Africa, par ticularly in South Africa, Botswana, Zambia and Mozambique,' says Jeffrey, ‘and the work has been varied – including geological reviews, resources and reser ve reviews, exploration management, mining studies and competent persons’ repor ts.'

Turning South Africa’s coal to account, however, is become increasingly difficult. With much of the countr y’s easily accessible deposits now depleted – in the Witbank coalfields, for example – the resources now targeted are often more geologically complex and expensive to mine, according to SRK chairman Roger Dixon.

As a founder member of the South African Mineral Resource Committee and currently the South African representative on the global Committee for Mineral Reser ves International Repor ting Standards, Dixon highlighted the ‘modifying factors’ that underlie a realistic assessment of economic value in a coal deposit.

‘The geological complexity of a deposit, for instance, features strongly among the modifying factors to be applied when conver ting a coal resource to the status of reser ve,' he says. ‘The coal geology of the Waterberg is challenging, and this requires investors to be especially vigilant about how exploration results are gathered and interpreted.'

Emphasising water management issues facing coal mining was SRK par tner and principal hydrologist Peter Shepherd, who warned that SA’s water resources were under strain and that new mines could only be brought on stream if they found innovative ways to meet their water needs.

Shepherd was encouraged by the steps taken by mines to conser ve water, but says the price of water could double in the next five years as a reflection of its real cost to society.

On the broader sustainability theme, SRK par tner and principal sustainability consultant Donald Gibson, welcomed the gradual acceptance of ‘shared value’ as a

principle to underpin a more developmental role for mining; the challenge, he says, was for better implementation of sustainability strategies in day-to-day operations.

He also says that the carbon tax to be introduced in 2016 will affect the coal sector along with many others.

‘South Africa is star ting to accept that carbon emissions must be priced,' says Gibson. ‘The fact that organisations can pollute the atmosphere and not pay for the negative impacts of that pollution is one of the most obvious market failures – hence the carbon tax. It remains to be seen whether South Africa will structure the tax appropriately to avoid affecting competitiveness. South Africa’s carbon intensity is a key factor that needs to be considered in decision-making at both government and mining company level.'

Senior mining engineer Xolani Gumede shared insights on blast design and blast optimisation, to reduce carbon emissions and mining costs. He stressed the value of blasting advisor y ser vices that are not directly linked to a ser vice contract – to avoid possible conflicts of interest in the advice given.

The projects served by our Johannesburg office have been mainly in Southern Africa, particularly in SA, Botswana, Zambia and Mozambique” Lesley Jeffrey, principal coal geologist at SRK Consulting

RéSource May 2014 – 31

Energy efficiency

Minimising energy waste in heavy-duty enterprises

By Jack Ward, Managing Director of Power Provisioning Specialist, Powermode

Diesel-engine-driven baseline power generation in heavy industry is conducted on a massive scale in South Africa. It is the main source of electricity for many organisations operating in remote locations, such as mining companies, where the cost of grid connection is prohibitive or even impossible.

I

ts use is justified, as many believe it will take years before SA’s electrical power grid and attendant infrastructure will be capable of meeting current and future expansion needs.

Unfortunately, diesel generators are expensive to operate and energy inefficient. In addition, there are the logistical problems of transporting the fuel to be considered.

These factors have a strong influence on the overall power generation costs. Until now, however, diesel power generation has proven to be the only viable solution for many companies.

Increasingly, renewable energy components are being added to these diesel-based systems in moves to supply reliable power solutions combining naturally occurring power resources with the benefits associated with dependable baseline diesel generation.

Renewable energy components such as wind power have performed successfully in trials, but SA’s wind climate seems to be best suited to this application only in coastal regions.

Solar-powered projects have proven to be more reliable, thanks to SA’s climate in which solar irradiation is abundant. Moreover, they have proven to require less development time before providing attractive yields.

Of the various solar options available, solar photovoltaic (PV) power has stepped forward as a desirable way to boost efficiency, minimise energy waste, reduce spiralling fuel bills and improve CO2 emissions at minimum cost.

Solar PV provides a means of reducing the amount of diesel generation during daylight hours, giving companies the ability to slash their fuel bills by up to 60%. It also saves wear and tear on the diesel generators and significantly extends the time between major services.

These solar PV-diesel hybrid solutions are gaining broad acceptance. The technology is maturing quickly with fast-to-implement installations springing up in remote sites around the globe, as a return on investment can be achieved in around three years. The falling prices of solar PV panels underpins such a short amortisation period.

In South Africa, this allows heavy industrial projects in remote areas, previously dependant solely on diesel power generation, to be launched on a totally new level of profitability. Already, solutions with capacities ranging from 200 kW to multiple megawatts have been commissioned.

The challenge in terms of application lies in technically conceiving and implementing a solar PV-diesel hybrid system without the use of energy storage systems (batteries), which are costly, and whose temperature sensitivity and limited lifespan are limiting factors when the longevity of the entire system is considered.

How does the system work? Basically, the solar PV system complements the diesel generators by substituting PV energy during the daytime to reduce diesel consumption. This has a direct fuel- and energy-saving implication.

Solar PV provides a means of reducing the amount of diesel generation during daylight hours, giving companies the ability to slash their fuel bills by up to 60% 32 – RéSource May 2014

There are many benefits associated with the deployment of solar PV technology in this scenario. First, solar PV systems are flexible and can be expanded on a modular basis as the energy demand grows.

Solar PV reduces the risks associated with future price increases and supply shortages, thanks to optimised planning. And, as mentioned, minimal CO2 emissions protect the environment and can facilitate CO2 certificate trading.

There are two key components of a solar PV-diesel hybrid system. The first is the PV inverter which converts direct current to alternating current (AC) at the required voltage and frequency for use by the installation’s transformers, switching and control circuits. It must remain productive in harsh ambient conditions, such as heat, moisture and salty air, among others, and it should be designed to cope with high voltage and frequency fluctuations.

There are two inverter options; centralised and decentralised designs. In the former, there is only one string or link to the inverter, while in a decentralised system, the solar PV power is divided into many strings, which are converted into AC by several inverters, all of which will have to perform grid-management functions.

The choice between a centralised or decentralised system depends on many factors centred on installation and operating costs.

For example, maintenance work on a decentralised system is not complicated. If service is needed, local electricians can replace individual inverters. However, remote monitoring and management are simpler tasks for a centralised system structure to handle.

An intelligent management system is the second key component of a solar PV-diesel

RR006A

Energy efficiency

hybrid system. This software-based solution provides the interface between the generator, solar PV system and the load, managing demand-based PV feed-in to the diesel-powered grid. Its performance is directly associated with the value of reduced fuel costs and the reduction in quantity of CO2 emissions.

Application-specific load profiles, such as heavy-duty industrial loads for mining, or the processing raw materials as well as for agricultural use, are generally characterised by loads with high starting currents and widely fluctuating load curves.

Intelligent system management ensures that generation and load are perfectly matched. Constant system stability should be achieved by reacting quickly to generation and load performance spikes, such as when a conveyor belt is turned on.

What level of savings can be realised? In a modern solar PV-diesel hybrid solution around 60% of solar PV capacity, compared to installed generator capacity, is the target. This means 600 kilowatt of solar PV power should be generated for every megawatt of installed generator power, on average.

Of course, solar power can only be generated during daytime, so variances in the actual day/night load profile could affect this percentage.

Nevertheless, as an example, when a one megawatt diesel plant with 24-hour base load generation is supplied with 600 kilowatts of solar power, for an average of 12 hours per day, savings of more than seven million litres of fuel can be realised over 25 years – the installation’s projected lifespan.

This translates into approximately R85 million at the current diesel price point. In addition, a reduction in greenhouse gas emissions of over 25 000 tonnes during this period could be achieved by this plant.

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Technical paper

Landfills’ new regulatory requirements

Dr Suzan Oelofse of the CSIR presented at the Landfill 2013 conference which was jointly organised by the Institute of Waste Management and GIGSA. This is an abridged version of the full paper.

A

vailable data indicates that domestic waste is disposed of on approximately 1 203 general waste landfills in South Africa and hazardous waste on 77 hazardous waste landfills.

Historic problems with municipal landfills include sites that are poorly sited, designed and operated and thus impact negatively on both the environment and quality of life. The main reason for the historic problems is the fact that many of these landfill sites were

34 – RÊSource May 2014

established before environmental legislation was in place. The first step to protect the environment and the public from the impacts of bad waste disposal practices was to implement a control system involving permits for landfill sites.

The minimum requirements on its own did not have any legal standing but became legally binding once incorporated as conditions into disposal site permits. The minimum requirements could therefore only be

enforced on permitted landfill sites. The consequence of this situation was that landfills that were not in line with the minimum requirements could not be permitted. This resulted in a total of 461 unauthorised landfills (as of October 2007) in South Africa.

One hundred and two of these sites needed authorisation for closure (present environmental fatal flaws and have a lifespan of less than three years) and the remaining 244 needed to be authorised for continued

Technical paper

This paper will therefore specifically only focus on those changes in legislation that impact on landfilling in South Africa.

2. National Environmental Management: Waste Act and landfilling 2.1 Landfill Licences The Waste Act introduced licences for a range of listed waste management activities, including disposal of waste to landfill. The licence application process will require a basic assessment or a full assessment in terms of the environmental impact assessment regulations, depending on the size and nature of the

2007 census are implied here. Goal seven of the National Waste Management Strategy, established in terms of the Act is to provide measures to remediate contaminated land sites. Assessment of 80% of the sites reported to the contaminated land register must be completed by 2016. It should, however, be noted that Sections 35-41 of the Waste Act, dealing with contaminated land, is not yet in force.

2.3 Waste Management Hierarchy Including the internationally accepted waste management hierarchy as one of the objectives in the Waste Act promotes alternatives

Historic problems with municipal landfills include sites that are poorly sited, designed and operated and thus impact negatively on both the environment and quality of life

use (do not present any environmental fatal flaws or can be upgraded to conform to the objectives of the minimum requirements and have a lifespan of more than three years remaining).

The promulgation of the Waste Act, (Act 59 of 2008) (RSA, 2009a) changed the legal landscape for waste management in South Africa quite significantly. It is the first South African law dedicated to waste management and provides a framework for effective waste management practices in South Africa. In addition, the shortcomings in the application of past legislation to South African landfills also needed to be addressed under the Waste Act.

disposal activity. A basic assessment process is required in the following instances: • Disposal of inert waste in excess of 25 tonnes and with a total capacity of 25 000 tonnes, excluding the disposal of waste for levelling and building purposes, which has been authorised by or under other legislation.

• The disposal of general waste to land covering an area of more than 50 m2 but less than 200 m2 and with a total capacity not exceeding 25 000 tonnes.

• The disposal of domestic waste generated on premises in areas not serviced by the municipal services where the waste disposed does not exceed 500 kg per month.

A full environmental impact assessment is required for the disposal of any quantity of hazardous waste and the disposal of general waste to land covering an area in excess of 200 m2.

It should be noted that the list of activities requiring a waste management licence is under review by the Department of Environmental Affairs.

2.2 Contaminated Land The Waste Act provides a legal mechanism for remediation activities at contaminated sites to be instigated and controlled. In 2010 the DEA produced a draft notice on ‘high risk activities' in terms of Section 36(1) of the Waste Act. The owner of land on which hazardous waste was disposed without a licence would in terms of this notice have to conduct a site assessment, within a period of two years of the date of the notice. The owners of the unauthorised hazardous waste landfills identified in the

to landfilling. The result of this inclusion in the Act is that landfilling is no longer the preferred waste management option in South Africa.

Therefore disposal should only be considered after all other waste management options have been exhausted, including waste minimisation, reuse, reduce, recycling or treatment to reduce the volumes and risk associated with waste going to landfill.

3. Waste Regulations Section 69 of the Waste Act lists a number of regulations that could have an impact on landfilling in South Africa, if developed.

The possibility of regulations that can prescribe the manner in which particular waste streams, or priority waste streams, must be dealt with and managed is of particular interest to this discussion. To date the choice of technology applied to the approved treatment and disposal of a particular hazardous waste stream, has not been prescribed. Therefore it will be interesting to see if this approach will continue to be applied in the development of these regulations.

The Waste Classification and Management Regulations and the Waste Information Regulations have been passed and must be implemented.

3.1 Waste Classification and Management Regulations Waste Classification and Management Regulations, 2013 have been developed under Section 69 of the Waste Act. The purpose of these regulations includes the introduction of a new waste classification

RéSource May 2014 – 35

Technical paper

system and requirements for five years. Information submitthe disposal of waste to landted thereafter must be based The National Waste Management fill. Including requirements for on actual quantities. All inforStrategy was established in terms of disposal of waste in regulamation submitted to SAWIS Section 6 of the Waste Act tions, automatically gives it must also be kept on record legal standing unlike the miniby the person submitting the mum requirements that first information for a period of needed to be incorporated into five years. permits to gain legal standing.

Implementation of the Waste The regulations that came into Information Regulations resulteffect on 23 August 2013 are ed in compulsory registration therefore also applicable to unliof landfills on SAWIS. Recordcensed sites as opposed to the keeping of tonnages and waste minimum requirements that types landfilled is now comcould only be enforced on perpulsory for all landfills with an mitted sites. For full details area in excess of 200 m2 and reporting of waste data into a on waste classification and management, please contact the editor of the case of general waste, if the disposal area national system is a requirement. is in excess of 200 m2. Reporting of waste RéSource at maryke@3smedia.co.za. data to SAWIS commenced 90 days after the 4. National Waste Management Strategy 3.2 Waste Information Regulations The National Waste Management Strategy end of the registration process.

The National Waste Information Regulations A person submitting information on haz- (NWMS) was established in terms of Section came into effect on 1 January 2013. Persons ardous waste must submit the information 6 of the Waste Act. The problem statement in disposing of waste to landfill must register on based on actual quantities while information the NWMS identifies a shortage of compliant the South African Waste Information System on general waste may be submitted based landfills and hazardous waste management (SAWIS) if the waste is hazardous waste or in on an estimation of quantities for a period of facilities as a hindrance to the safe disposal 36 – RéSource May 2014

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Technical paper

of all waste streams. A target of 80% of waste disposal sites with permits by 2016, has been set by the strategy.

The NWMS also set targets for amongst others, diversion of recyclable waste away from landfill. In addition, it notes that the National Norms and Standards for Disposal of Waste to Landfill provides for diversion of particular waste streams from landfills within prescribed timeframes. In this regard, municipalities are given the responsibility for diversion of organic waste from landfill but the strategy does not set targets or time frames relating to organic waste diversion.

Such targets are now set in the National Norms and Standards for Disposal of Waste to Landfill, notably a 25% diversion of garden waste from baseline at a particular landfill in five years and a 50% diversion in 10 years.

5. Conclusions The most important changes as a result of the implementation of the Waste Act, and subsequent development of regulations, norms and standards, is stricter regulation of waste

management activities including disposal of waste to landfill. The fact that the waste management hierarchy is included in the Waste Act and will be implemented through various mechanisms including norms, standards and regulations should result in less recyclable waste finding its way to landfill. It is also expected that the introduction of new technologies may result in a change in composition and characteristics of waste streams being disposed of at landfill.

The most drastic change is expected to come with the implementation of the Waste Classification and Management Regulations, 2013. The approved new approach for assessment of waste for landfill disposal requires more, and more complex, analytical processes which in turn is more costly than the previous system. The fact that analyses will in future have to be done at accredited laboratories is another complicating factor.

There are a limited number of accredited laboratories available that are equipped to analyse waste samples. Establishing more of these laboratories will be costly as the required equipment does not come cheap.

Accreditation of a new laboratory is also not a trivial thing and may take a year or longer to obtain.

The results of the analyses under the new regulations may also have a different outcome as compared to the classification system contained in the minimum requirements (DWAF, 1998a), that is, wastes that were previously classified as hazardous may no longer fall into this category and vice versa. A change from a previously hazardous waste category to a non-hazardous waste category and vice versa, may have serious implications for landfill operators now having to accept and manage waste streams that were previously not disposed of at their landfills. The magnitude of the change in waste categories will only become evident with the implementation of the regulations.

Therefore it can only be speculated what the impacts on available landfill airspace, operations, cost and income generation potential of landfills will be.

Standards for waste disposal are nationally applicable and enforceable irrespective of whether it is incorporated as conditions RéSource May 2014 – 37

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RéSource May 2014 – 37

Technical paper

in landfill licences or not because all regula- a concern for municipalities where available Advantages of the expected changes tions issued in terms of the act have legal landfill airspace is limited, but it may provide in waste characteristics entering landfills standing. This approach is significantly dif- stimulus for diverting waste away from landfill in the future include that landfills may ferent to the minimum requirements that for reuse and recycling. become less attractive to informal pickers made provision for defensible deviation Successful implementation of policy and and expected lifespans of municipal landfills where site specific factors are such that strategy should, over time, result in a change will be extended. the rule cannot or need not be applied in the characteristics of waste being disAlthough record-keeping of waste volumes (DWAF, 1998b). In addition delisting of haz- posed of at landfills. It can reasonably be disposed of at landfills was a requirement in ardous waste streams terms of the minimum and exemptions are requirements, at the practices of the past majority of larger genwhich are not allowed eral waste and all hazunder the Waste Act ardous waste landfills, and its regulations. the implementation of This is a significant difthe Waste Information ference as compared Regulations (RSA, to what was in place 2012d) has added a under the Environment registration and reportConservation Act. ing requirement on all The classification syslandfills. In addition, tem for landfills has also estimations of waste changed with the new quantities have to be regulations. Following phased out over a fivethe minimum requireyear period. Therefore, ments, landfills were landfill operators have classified based on type to introduce measures Waste accepted by the different classes of of waste disposed, size that will result in the landfills is now determined by the waste of site and potential capturing of accurate acceptance criteria outlined in the National for leachate generation data of tonnages and Norms and Standards for Disposal of Waste (DWAF, 1998b). The the different waste new approach classifies types landfilled at all to Landfill landfills based on consites in order to comply tainment barrier design. Waste accepted by expected that less recyclable waste will find with these regulations. The environmental the different classes of landfills is now deter- its way to landfill. It is also likely that waste impacts associated with high impact, unpermined by the waste acceptance criteria out- sent to landfills in future will have undergone mitted landfills and dumpsites, which will lined in the National Norms and Standards for some pre-treatment, i.e. extraction of useful never qualify for waste disposal licences, Disposal of Waste to Landfill (RSA, 2013c). components, likely to change the nature and can be addressed through the provisions The costs of landfill design and construction appearance of the waste. If waste-to-energy on contaminated land in the Act. The fact in line with the new design requirements is in is actively pursued, large volumes of poten- that the relevant sections of the Act dealcomparison, significantly higher. This situa- tially hazardous ash may find its way to land- ing with contaminated land are not yet in tion may further limit the development of new fills. Therefore, landfill operators may have to force, is a particularly great concern, espelandfills and consequently increase the pres- adjust on-site operations to ensure continued cially in light of the potentially lofty target set sure on existing landfills. This is especially safe handling and disposal of all waste. in the NWMS. 38 – RÊSource May 2014

Mills & Otten cc Johannesburg Tel: (011) 486 0062 Fax: (086) 554 6573 Contact: Charles Mills / Kirstin Otten

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Renewable energy

Driving the solar agenda Renewable energy (RE) resources can possibly provide effective sustainable energy solutions. However, the application of solar energy for power generation purposes is not currently competitive with conventional fossil fuel systems.

A

recent academic study compared the solar-aided power generation (SAPG) solution with that of a similar-sized, stand-alone concentrating solar power (CSP) plant in the South African context. The objective was to determine the real advantages of these technologies, if any.

To determine the performance of the two types of RE technology, the study simulated a solar-aided power generation plant at Lephalale, Limpopo province, and compared it with a model of a standalone concentrating solar power plant near Upington, Northern Cape.

Solar-aided power generation The integration of solar-thermal collectors into conventional fossil plants, or SAPG, has proven a viable solution to address the intermittency of power generation and combines the environmental benefits of solar power plants with the efficiency and reliability of fossil power plants.

The basis of SAPG technology is to use solar-thermal energy to replace the bled-off steam in regenerative Rankine power cycles.

The increased steam output then enables additional power generation from the turbine (solar boosting mode) or fuel consumption can be reduced (fuel-saver mode).

The temperature of the heat source is one of the major defining factors of a power plant – higher temperature results in higher overall power-plant efficiency. With SAPG, the heat-source temperature is not limited by the solar-input temperature and is therefore an effective means of utilising low or medium solar heat (250˚C) for power generation. However, internationally, the adoption of the technology has been slow, despite it being a viable and quick means of CO2 emission reduction.The study was conducted on a simulated SAPG power plant at Lephalale,

which was based on a generic 600 MW electric subcritical fossil power plant with a reheater and regenerative Rankine cycle with two low-pressure feed-water heaters (FWH) downstream of the deaerator and three high-pressure FWHs upstream.

Stand-alone CSP CSP plants convert the sun’s rays into high-temperature heat using various mirror configurations. This thermal energy is converted to mechanical energy with a heat engine (e.g. a steam turbine) and ultimately to electricity, utilising a generator.

The plants consist of two parts: one that collects solar energy and converts it to heat, and another that converts heat energy to electricity. Thermal energy storage is a possible addition which accommodates dispatchable power – a drawcard for solar thermal amongst RE resources.

For the study, the plant was simulated in the solar booster mode, which has proven to produce more rewarding and stable results than the fuel-saving mode.

The following components, which are standard to power plants with steam turbines, were integrated into a whole-plant model: • Boiler – with a furnace, water walls, drums, evaporative bank, superheater, reheater, economisers and air heaters.

• Steam turbine – extraction condensing type with high-, intermediate- and low-pressure sections.

• Electrical generator – no gearbox included.

• Condenser – heat exchanger between turbine exhaust steam and cooling water from cooling towers (either wet or dry).

• Feedwater system – feedwater pumps and heaters.

With the above components, a sequential approach was followed and heat and mass balances were per formed with efficiency analyses.

SAPG and CSP comparison The case study compares a SAPG plant in Lephalale, home to the Matimba and under-construction Medupi coal-fired power stations, with a CSP plant near Upington, a very good solar-resource area. In order to make a direct comparison with the SAPG, the solar field for the CSP plant was unaltered – an actual aperture area of 80 000 m2 was used, equating to around 50 MW thermal-peak capacity. No thermalenergy storage was considered.

Annual simulations at a conventional north-south orientation were per formed.

Parabolic trough collectors are the most mature concentrating solar technology and were used for the simulations. The selection

SAPG combines the environmental benefits of solar power plants with the efficiency of fossil power plants

RéSource May 2014 – 39

Renewables

of suitable solar-collector technology is outside the scope of this study.

Furthermore, the same power-block specifications were used for both plants. From a SAPG perspective, this can be seen as being conservative.

The stand-alone CSP plant is a complete plant, including solar field, power block and balance of plant, while the SAPG is essentially a solar field integrated into a power plant. The National Renewable Energy Laboratory developed a component-based cost model for parabolic trough solar-power plants for use with System Advisor Model.

From this database, the cost of SAPG was extracted as 72% of that of a stand-alone CSP system (solar multiple of 1.1 with no storage).

thermal energy, SAPG proved 1.5 times more efficient than CSP (similar results were found in previous studies).

• Ultimately, the annual electricity generated from solar thermal at the SAPG plant is over 25% more than from the standalone CSP plant.

• The breakdown of costs showed that SAPG is 72% of the cost of CSP. Therefore, a SAPG feedwater heater system at an existing coal-fired power station is 1.8 times more cost-effective than a standalone CSP plant.

A 2012 study, The value of hybridizing CSP, found SAPG to be competitive with largescale, ground-based photovoltaic plants in terms of ‘levelised’ cost of electricity.

Results

Conclusions

While the solar resource at Upington, in terms of annual total direct normal irradiation, is 20% higher than at Lephalale, the study found that: • In terms of the conversion of solar

SAPG is a more viable solution for South Africa in the short to medium term, with its significant coal base and good solar resource, and is comparable to large-scale, ground-based photovoltaic plants.

SAPG has a high potential for localisation of manufacturing

In South Africa and other developing countries, CSP has been identified as having a high potential for localisation of manufacturing, thereby, creating jobs and stimulating the green economy.

SAPG has a higher local content potential than stand-alone CSP due to simpler sub-systems.

SAPG can assist utilities to meet their CO2 emission reduction targets in a quick and feasible manner.

SAPG is a mechanism for the deployment of large-scale CSP technologies.

The innovative concept of SAPG allows conventional coal-fired power stations the ability to generate renewable electricity. The integration of solar energy into conventional power stations provides a viable solution to overcoming the numerous legislative and cost-related issues of implementing large-scale RE.

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Envitech Solutions

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Pikitup

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Wastecon 2014

40 – RéSource May 2014

4

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