The process of converting wind energy into electrical energy is actually very efficient compared to using fossil fuels where a lot of heat energy is wasted. Wind turbine efficiency is often confused with capacity factor. If a wind turbine worked at its maximum capacity all of the time then it would have a capacity factor of 100 per cent. However, the wind does not blow all the time so a typical wind turbine has a capacity factor of around 30 per cent. This means it produces 30 per cent of its theoretical maximum output each year.
The map on the right shows the average wind speeds across Europe and indicates that the north of England and Scotland has the best wind resources in the whole continent.