The 10 big energy myths

"Myth 2: wind power is too unreliable 

Actually, during some periods earlier this year the wind provided almost 40% of Spanish power. Parts of northern Germany generate more electricity from wind than they actually need. Northern Scotland, blessed with some of the best wind speeds in Europe, could easily generate 10% or even 15% of the UK's electricity needs at a cost that would comfortably match today's fossil fuel prices."

http://www.guardian.co.uk/environment/2008/nov/27/renewableenergy-energy