The big challenge, wind developers acknowledge, is modifying site permits that restrict the spacing and height of turbines. Neighbors are often put off by the visual impact of the turbines themselves ...Wind developers face an additional hurdle to repower in Denmark, where legislation going into effect next year will require wind-park operators to compensate residents if wind turbines reduce their property values.

They introduced the world to "environmentally friendly" energy, but now some of Europe's "greenest" countries are under pressure to backtrack on wind farms as public anger grows over their impact on the countryside.