Turbine at Noble Ellenburg
According to ConEdison Solutions—which just sent me a certificate to make its point—Lantern Books managed to purchase 760 kilowatt-hours of green energy in 2008. The certificate states that "In satisfaction of your 2008 purchase of wind power, this certificate verifies that clean, emission-free electricity in the amount shown above was produced and delivered to the electric grid." The sources? "The Fenner, Madison, Maple Ridge, Noble Bliss, Noble Clinton, Noble Ellenburg, Steel Winds, and Wethersfield Wind Farms, as well as other wind farms in the region."
How much is 760 kWh? About enough to run an energy-efficient fridge for one year. It's not much, but I guess it's a start.