Sarens (On Vs. Offshore Wind Farms

Image sourced: www.sarens.com/services/wind.htm

Author: Sarens

Wind, the response to the energy demand of the future

For years, the world has been immersed in a major paradigm shift in energy demand and consumption. In part due to geopolitical factors, which define how important energy sources will be in the immediate future, but also due to various international regulations seeking to reduce greenhouse gas emissions to achieve better living conditions for citizens worldwide.

During the COP26 in November 2021, it was clear that governments worldwide have to redouble their efforts to achieve the goals set by the Paris Agreement to reduce global warming by 1.5 degrees compared to the pre-industrial era. And at the next COP, the trend will continue in the same vein.

Australia is not an exception. During the COVID-19 pandemic, energy demand slowed down significantly, but this didn’t slow down the transition to cleaner energy sources. It’s important to raise that our region continues to rely, for the most part, on coal-fired electricity generation: up to 51% of the electricity produced across our continent comes from this source, which is the most damaging to the environment and, therefore, to the health of our citizens.

In contrast to this worrying figure, 29% of all energy produced came from renewable sources in 2021, according to the Australian Energy Statistics 2022 prepared by the Department of Climate Change, Energy, The Environment and Water. In addition, 19.1% of the energy consumed in Australia already comes from wind power.

Our region must become a world leader in this type of energy generation. Approximately 1% of all wind power installations in the world are located in our territory, with 75 wind farms already in operation. The contribution of these installations goes beyond the energy sector, as they generate employment in the areas where they are installed, both in their installation and later in their maintenance, and in the form of taxes and rents for the landlords on which they are installed.

This, of course, is also a significant boost to the construction industry. Each of these wind farms requires the installation of foundations, the transport of the wind turbines from where they are manufactured to their final location and, once there, their hoisting. This overcomes all kinds of technological challenges, as these are infrastructures weighing hundreds of tonnes and are installed in areas that are usually difficult to access. A task, in short that requires great precision, which is why it’s important to turn to companies like Sarens, which have participated in hundreds of similar installations all over the world, and also have the capacity to advise and collaborate throughout the process and to choose the necessary machinery at all times.

OFFSHORE WIND ENERGY AS A NEW SUSTAINABLE ALTERNATIVE

As a complement to traditional wind farms, a new type of wind energy exploitation is becoming increasingly common all over the world: offshore wind power. Unlike traditional wind farms, each wind turbine is installed at sea, sometimes dozens of kilometres from the coast, to take advantage of the greater power of the wind currents produced there. Australia has not wanted to lag behind in exploiting this modality, and at the beginning of August 2022 announced the approval of the first wind farm of this type on the coast of Gippsland, in the southwest of Victoria. This project will soon be joined by projects in the Hunter Valley and Illawarra in New South Wales, in Portland, Victoria; northern Tasmania; Perth; and Bunbury in Western Australia.

Approximately 1% of all wind power installations in the world are located in our territory, with 75 wind farms already in operation. The contribution of these installations goes beyond the energy sector, as they generate employment in the areas where they are installed, both in their installation and later in their maintenance, and in the form of taxes and rents for the landlords on which they are installed.

These installations are also full of challenges. The first, and perhaps the most complicated, is connecting the entire infrastructure to the grid, which is usually located far from the coastal area. The actual transport and installation of each wind turbine also require specialised work such as that carried out by Sarens, as it is necessary to load each structure onto barges, usually semi-submersible. Each piece must then be anchored, either directly to the seabed or installed on floating structures, which are more respectful of the seabed and the natural ecosystem and allow for faster and more efficient installation and dismantling.

Regardless of the type of installation, it is necessary to carry out maintenance on each unit throughout its useful life to avoid downtime. Having the machinery and specialised personnel for this can end up being an important competitive advantage to ensure the success of any new or existing project. Sarens assure our commitment to wind energy to secure Australia’s electricity supply in a much cleaner and more sustainable way.

It’s important to raise that Sarens owns extensive international experience in the assembly and maintenance of wind farms. The company is currently participating in some of the most critical projects in the world, such as SaintNazaire in France, Provence Grand Large or, more recently, in the lifting and transport of the foundation bases of the new offshore wind farm in Saint Brieuc, off the Brittany coast, where it has been able to transport loads of more than 1,150 tons. Those works demonstrate how important it is to have specialists who can ensure the project’s viability and maximise cost reduction and efficiency throughout the implementation phase.

The future will be full of significant challenges, but only with the commitment of all stakeholders, companies, institutions and individuals will Australia be able to meet them all successfully.

BENEFITS AND DISADVANTAGES OF ONSHORE WIND FARMS

BENEFITS

Cheaper to install.

As it is not necessary to use barges to move the wind turbines several kilometres offshore, the transport logistics are considerably cheaper. Similarly, it is not necessary to carry out marine excavation work to prepare the foundations for each wind turbine using specialised machinery.

Shorter cabling is required for operation.

It is possible to install the substation that converts the energy produced by the wind turbines to high voltage just a few metres from them, which reduces the need for long cable runs, sometimes tens of kilometres long, while at the same time reducing their impact on the land. Connection to the grid is also easier.

Low environmental impact.

Wind energy does not produce any type of waste in its generation, and wind turbines do not cause pollution in their environment so that the land on which they are installed can be exploited both for agriculture and livestock with no risks.

Easier and faster maintenance.

As they are more accessible installations, any maintenance manoeuvre, both predictive and corrective, only requires the participation of a crane and the necessary technical equipment.

Smaller wind turbines with low visual impact on the environment.

Although they tend to have heights that sometimes reach 100 metres to benefit from the wind currents produced at higher altitudes, the blades and turbine module size are smaller.

DISADVANTAGES

Lower power generation capacity.

Due to the smaller size of its blades and the low power of the wind gusts produced on land, this modality generates less energy, with an average of approximately 2.5 MW per year.

Variable wind speeds.

As wind gusts and wind speed change direction on land, it is not always possible to maximise the use of wind turbines, although, in their installation, the optimal orientation is studied to minimise this effect.

Noise pollution.

As the blades are in motion, their aerodynamic noise can become unpleasant if exposure to this sound increases over time.

BENEFITS AND DISADVANTAGES OF OFFSHORE WIND FARMS

BENEFITS

Increased power generation capacity.

Marine winds are more intense and frequent, which maximises the performance of each wind turbine, up to a capacity of more than 3.5 MW per year.

Greater wind consistency.

As no obstacles can deflect the gusts of wind (mountains, towns, etc.), the wind that reaches the wind turbines is more stable.

Less visual impact.

Wind turbines can be installed dozens of kilometres from the coast, so they can be larger and have less visual impact than those installed on land.

Low environmental impact.

Especially in the case of the new floating type (FLOW), in which damage to the seabed is reduced depending on the type of anchoring used.

Easier and faster dismantling.

In the case of floating wind farms, the dismantling time is exponentially reduced while minimising the impact on the seabed once unanchored. All of this also reduces costs.

DISADVANTAGES

More expensive installation.

Unlike onshore wind farms, this type of installation requires construction infrastructure in a nearby port, specialised dredging machinery and barges to move the wind turbines on multiple trips.

More expensive maintenance.

Benefiting from stronger and more intense winds, rotor maintenance is higher and more frequent. Likewise, the continued impact of waves increases the wear and tear on the poles, which increases the need for regular servicing of the installations.

Longer cable runs.

As the entire installation is carried out kilometres from the coast, kilometres of cable must be laid on the seabed, a more complicated, delicate and expensive task.

it is important to remember that wind energy comes from an inexhaustible source, and its generation does not produce any waste, making it one of the cleanest sources of energy.

HOW SARENS SEES THE FUTURE OF WIND ENERGY

When the world is turning to renewable energy as a more environmentally friendly energy source, it is important to remember that wind energy comes from an inexhaustible source, and its generation does not produce any waste, making it one of the cleanest sources of energy.

Although the first steps are already being taken around the world to extend this type of energy, there is still a long way to go. The future, in this sense, will be bright for wind energy if the kilometres of coastline present in Australia are used to extend the offshore mode and if the onshore projects already in operation are consolidated and properly maintained. From Sarens, we offer all our support and international experience to both public institutions and construction companies involved in developing wind energy facilities so that the future of this energy is bright and contributes to reducing the impact of the current energy crisis and dependence on unsustainable sources.