It is rated at 450W but it needs a good wind to do it. Ideal for marine applications or first class inland wind sites. It performs rather poorly in low wind areas as the compromises made to get the high top end performance ( sells better) make it virtually useless below 10 mph.

Energy capture is much more related to prop diameter than alternator maximum rating.

Most wind areas produce 90% of the energy in winds below 20 mph. A well designed 100W machine set up for low wind will capture more energy in most inland sites.