other sensors

Besides the wind speed you need the air temperature, humidity and air pressure to calculate wind energy. Wind direction does not influence the wind energy calculation directly, but is very useful for the layout of the wind farm and siting of the individual turbines. 

There is a broad variety of additional sensors available: bat corders help to determine whether there is endangered species of bats located at the site, precipitation sensors help to get an idea about when those bats are flying and when they stay at home (as recent studies found that bats avoid flying in the rain), solar radiation sensors can give an indication about the use of solar power at the site.