Wildlife Impact

Bats
Why wind turbines cause bat deaths in far greater proportion than bird deaths: internal bleeding due to pressure changes between blades.
http://www.sciencedaily.com/releases/2008/08/080825132107.htm

Impact of Wind on CO2 Emissions

Denmark

Denmark generates 20% of its electricity from wind, and has reduced its carbon dioxide (CO2) emissions by 23%. However, wind seems to have been a minor factor in the CO2 emissions reduction. Energinet.dk, the owner and operator of the Denmark's electrical transmission grids, attributes most of the reduction to the replacement of coal with natural gas. Read the Environmental Report 2008. (see pages 26 and 27)

Germany

"Wind turbines in Europe do nothing for emissions-reduction goals"
http://www.spiegel.de/international/business/0,1518,606763,00.html
This story in a prominent German newspaper discusses the limitations of wind power in reducing CO2 emissions, which even Green Party representatives admit.