But prices are now falling, and other trends identified in the Depart­ment of Energy’s 2010 Wind Technologies Market ­Report suggest that last year could be a low point for American wind rather than a new norm.

The report, written primarily by Ryan Wiser and Mark Bolinger of the Lawrence Berkeley ­National Laboratory, summarises the main factors contributing to the fall-off in installations last year: “The delayed impact of the global ­financial crisis, relatively low natural-gas and wholesale electri­city prices, and slumping overall demand for energy”.

The