Question:

I recently visited a wind farm in Vendée (France). By comparing the stated output of 20 MWe to the power produced, I was able to deduce an annual operating time of about 2,500 hours. Is this a profitable investment?

Answer:

For an energy production of 45,660 MWhe and an installed capacity of 19.5 MWe, the average annual operating time for the eight generators on the farm is 2,340 hours. Given that there are 8,760 hours in a year, the “availability” of this facility is therefore just over 26%, which is low compared with other power generation methods. To be considered as being sufficiently windy, a wind farm site must provide more than 2,600 hours of production per year. But we should not forget that in this area, cost is separate from price. Thus, in France, as for most European countries, legislation requires that power companies buy wind-generated electricity at a high price as an incentive for the development of renewable energy sources.