By Diane Kittower
To assess the wind power (expressed as wind speed) in an area, you can either estimate or take a precise measurement, which will cost more. It costs nothing to look at wind maps of your site's area -- there are several Web sites that offer them (rredc.nrel.gov/wind/pubs/atlas, www.nrel.gov/wind/statemaps.html, and ncdc.noaa.gov).
Airports and weather bureaus often have wind-monitoring stations and will share the information freely. Ask them where their stations are, so you know how close and how similar their situation is to yours.
Use your eyes, too. Are trees bent or deformed after years of wind blowing on them from one direction?
If you want to pin down the wind speed, you'll need an anemometer, which costs $500 to $1,500. It measures both speed and direction and can be rented or bought. If possible, put the anemometer at the same elevation as the top of the wind turbine tower would have. Monitor the anemometer for a period of time to get enough consistent data.
Looking for case studies, statistics, wind power maps, and resources? Start here.
American Wind Energy Association, Washington, D.C. www.awea.org
Bergey Windpower Co. www.bergey.com
Database of State Incentives for Renewable Energy (DSIRE) www.dsireusa.org
Innovative Power Systems www.ips-solar.com
National Renewable Energy Library PIX Photo Collection www.nrel.gov/data/pix
National Wind Coordinating Committee www.nationalwind.org
Wind Power Monthly www.wpm.co.nz
Wind Powering America www.eren.doe.gov/windpoweringamerica
Earth Policy Institute www.earth-policy.org
Renewable Energy Policy Project and Center for Renewable Energy and Sustainable Technology www.crest.org
--Diane Kittower is based in Rockville, Md.
BIG BUILDER Magazine, March 2002