The Future of Floating Off-Shore Wind and What it Offers Us

We are all familiar with the sight of wind turbines in the countryside and alongside our motorways. You may also live near to, or have visited a coastal area and seen offshore wind turbines operating perhaps a kilometre from the shoreline. These types of wind turbine installations are named on-shore and off-shore respectively. However, there’s a third type of installation that is likely to offer up a solution to global energy needs – and that’s floating off-shore wind turbines.

The climate emergency has meant that there is an international race to design, develop, install and prove systems of generating energy in a sustainable, zero carbon way that can be deployed to meet the global energy demand and end our dependency on harmful fossil fuels. Different regions around the globe are likely to become reliant on several forms of generation in order to overcome limitations of availability resource such as sun, wind, suitable hydro. This also brings the benefit of not  becoming reliant on just one or two sources of critical power. The technologies allow countries to become self-reliant in terms of their own energy needs, and not beholden to the degree of political stability in oil and gas producing regions which have traditionally been as volatile as the fuels they export. An industry around renewable energy has now matured and is set to continue its exponential growth, with Photovoltaic (PV) and Wind Turbines playing a major role in meeting global energy needs.

It’s worth noting that while our focus is rightly on reducing CO2 emissions, the global community continues to focus on one big challenge at a time. The management and protection of fresh water as a resource remains on the fringes of the climate crisis debate, largely because scarcity of fresh water isn’t a challenge for first world nations. However, the role of water in our ability to sustain a healthy population is undeniable. Whether its drinking water, water for farming or water for manufacturing and industry, we can be certain that the global demand for fresh water is going to grow. Therefore the need for more and more desalination plants is in turn going to impose higher energy demands in water critical areas of the world.

The proliferation of on-shore and near to coast off-shore wind farms underlines the success of this form of solution, so why do we need to push technologies further and develop the floating off-shore wind turbine? The reasons are many and here are a few of the primary reasons. Onshore Wind Turbines remain controversial in terms of their visual and audible impact on the environment and for this reason, many projects get delayed and/or rejected at planning stage. For the same reason, near to coast off-shore wind farms receive opposition at planning stage and added to that, their installation can be disruptive to fishing and shipping activities. Floating off-shore wind turbines have little or no visual or audible impact on the environment,  being located ten kilometres or more from the coastline at sea depths of greater than sixty metres. As such, they rarely affect shipping lanes and where they do, amendments to shipping lanes are more easily accommodated as the depth of water means other man-made (wrecks) and natural obstructions are less common, while fishing activities are more easily adjusted also.

Equally as important, floating off-shore wind turbines are more efficient in the open seas as winds along sea surfaces are stronger and more consistent in terms of direction. This is because the surface of the sea, unlike the land, is a flat linear surface and therefore creates less friction for winds as they pass over the surface of the water, allowing them to gain higher speeds. Additionally, without obstructions such as hills, towns and cities, and forests the winds at surface altitude are not re-directed and therefore more turbulent.

The knowledge, science and technology necessary for the needed growth in the floating off-shore wind turbine sector is available to us today. Our understanding and ability surrounding wind-turbines for the purpose of power generation is now three decades old. Danish scientist and engineer Henrik Stiesdal installed the first off-shore windfarm in 1991 and continues to lead innovation to make larger and more efficient turbines. Recently, Stiesdal created a ninety four meter long turbine blade, a jointless, single piece blade that permits turbines to be yet bigger, and therefore more efficient. Advances in the technology surrounding off-shore wind turbines mean that costs associated with this type of generation are set to fall by 60% by 2040.  Stiesdal now focuses his attention on the development of energy storage to complement the advances in wind-power generation, and feels that his team are about to break through critical barriers in terms of both daily and seasonal storage.

Of course, we have been installing complex, vast floating structures at sea for years in the form of oil and gas drilling rigs. Through this time we have developed proven methods by which we can secure huge floating steel structures to the sea floor in a way that can overcome the power of tornados and other forces of nature. This knowledge has been applied to the off-shore wind turbine sector and the floating wind turbine installations which are present today all vary in the way that their installation floats. This is borne out of marine engineering knowledge largely associated with the off-shore petrochemical sector.

The potential for growing the global wind-turbine stock is huge. The International Energy Agency finds that off-shore wind has the capability to meet global energy demands eleven-times over. The technology we have in the sector today means that with just one revolution of a  wind turbine blade, enough energy is created for one typical European home for one day.

Its apparent that the growth of floating off-shore wind turbines will be an essential element of our global power generation solution as we move rapidly away from our reliance on CO2 producing fossil fuels. These technologies, along with other renewables, such as PV, will mean that more countries and regions will no longer be reliant on traditionally less politically stable regions for their essential fuel requirements, and can be self sufficient in terms of their own energy needs. Furthermore, clean low cost power can be afforded to the less wealthy regions of the globe offering a great opportunity for levelling-up wealth and opportunity around the globe and potentially reducing the potential for conflict between regions.