The capacity credit of wind power

What happens when the wind doesn’t blow? How much of a wind farm’s output can be relied on as “firm” capacity, and how much backup generating capacity is needed? The answer is in a measure called the “capacity credit”.

Cow-sized UFO prangs wind turbine

The “flying cow” is the new unit of UFO mass.

The capacity factor of wind power

A wind turbine’s ‘rated’ capacity is its maximum power at an optimum wind speed. This is the value commonly quoted for a wind farm’s ‘installed capacity’. How does this compare with the wind farm’s average power output? That is, what is the capacity factor of wind power?