Europe is turning green, but there may be costs

In March 2007, the European Union put flesh on its claim to be a world leader in fighting climate change by committing itself to boosting green energy, curbing air pollution and cutting energy bills, but a year later it is still struggling with the implications of these ambitious goals.

European leaders put a "greener Europe" high on their political agenda in the face of two main challenges: potentially catastrophic changes in world temperatures and sharply rising dependence on externa...