Floating Windfarms Show Promise of Low Cost Renewable Energy
The UK is off to a running start with windfarming. At present, the country has 538 wind turbines in offshore commercial farms that are producing 1,708 MW (megawatts) – as much as the combined production of the rest of the world! These bottom-mounted turbines work well in the shallow waters off the coast.
But it seems that the intriguing goal of having vast deep-water wind farms may soon be reached.
The benefits of deep-water turbines are considerable. The winds from miles offshore are stronger and more consistent, capable of providing untold amounts of clean, renewable energy. Instead of turbines attached to the ocean floor, these deep-water turbines float on the surface, avoiding any risk of disturbing the fragile ecosystems below the waves. Their distance from land puts them out of sight, where there are no issues of “visual impact” which has frustrated much use of land based wind farming in the UK
The WindFloat foundation, created by Seattle based company Principle Power, could be the key to realizing these goals. In Portugal, a 2-MW turbine was attached to a WindFloat platform. In November 2011, the whole thing was taken 350km out into the Atlantic Ocean. For the next two years, it will be tested while it send electrical power back to Portugal via an undersea cable.
The performance of the WindFloat will be closely monitored and compared with the performance of Statoil’s Hywind, another floating turbine located off the coast of Norway since 2009. The Statoil’s 2.3MW turbine is atop a steel cylinder that’s been filled with rocks and water as ballast; the turbine is then held in position by three mooring lines.
The WindFloat base uses three underwater columns for stabilization. The turbine itself is directly over one column that has little ballast; the other two columns are filled with more ballast so that their weight counterbalances the weight of the turbine. The triangulation of the three columns creates more stability.
An advantage of the WindFloat is that no heavy lifting equipment was needed to deploy the base and turbine, which created considerable savings in cost. While Principle Power has declined to disclose the commercial costs, it has been suggested that the project was completed for less than $30 million; compare that to the $75 million spent on Hywind. Observers will be keeping a close eye on WindFloat’s energy production, and comparing it to the 15 MWh (megawatt hours) generated by Hywind in its first two years.
In a story that warms the hearts of many renewable energy proponents, Japan is about to begin construction on a floating wind farm just off the coast of Fukushima. While the project is beginning with a 12 MW capacity, it is expected to be increased to as much as 1 gigawatt by 2020. The funding for the project is coming from monies budgeted for reconstruction after the 2011 earthquake/tsunami.
The news of Japan entering the floating turbine market is very encouraging to advocates of offshore wind energy production. By having a big industrial power like Japan get into the market, it could cause major reductions in cost, which would be a benefit worldwide.
Article contributed by businesselectricityprices.org.uk