The numbers are in... at least for 2006. According to the Worldwatch Institute, some 2.3 milion people worldwide were employed by the renewable energy industry that year, either directly or by one of their suppliers. The breakdown: wind power employs about 300,000 people, solar energy employs some 794,000 people, and biomass/biofuels account for more than 1 million jobs. The U.S. was responsible for about 446,000 of the green-collar jobs, and the numbers across the board are projected to continue rising.

The Worldwatch Institute points out that, by comparison, jobs in the American coal industry have dropped by half in the last 20 years, even though production has increased by a third. The reason for the sunset? Improved technology has displaced workers, whereas the renewable-energy industry still tends to be more labor-intensive. Of course, not all green-collars are created equal: the study duly notes the poor labor conditions for biofuel plantation workers in Brazil and Indonesia.

--Suzy Khimm