Windbreak walls boost efficiency
Obstacles in the landscape in front of wind turbines can increase wind speeds higher up in the air and so improve energy generation by up to 10%.
Wind turbines are a vital part of the solution for the many companies phasing out fossil fuels such as coal, oil, and gas. In the Netherlands scientists have found a method that can improve wind turbine efficiency by up to 10%.
You might assume that a flat landscape would be optimum for wind turbines, without obstacles such as hills, houses or vegetation to reduce wind speeds. But it turns out that obstacles can actually boost efficiency. A low wall in front of a wind turbine will force the wind upwards and so increase the wind speed at the turbine
wings. This delivers a more efficient wind turbine right behind the obstacle. However, studies have shown that the overall effect is negative if that wind turbine is located with others as part of a wind farm, because the other turbines lose more efficiency than the front one gains.
Scientists from the Dutch University of Twente have managed to find a solution. In the lab they simulated obstacles of different heights, widths, and locations in relation to a wind farm of 24 turbines, and they found that with the right obstacles, the total efficiency of the wind farm could
be improved by up to 10%. The obstacles must be round a tenth the height of turbines, and their width must be five times the height. So with walls or trees that match their criteria, the entire row of wind turbines should benefit from improved wind speeds.
The result shows that in spite of decades of experience with wind turbines, engineers can still optimise the technology. If all wind turbines in the world were made 10% more efficient, the increase in power generation would correspond to the power from 50 average coal-fired power plants.