Companies are stepping up their environmental initiatives, and that may mean a boom in "green-collar" jobs.

A recent forecast by the American Solar Energy Society found that renewable energy and energy-efficient industries were responsible for the creation of nearly 8.5 million jobs in 2006, and by 2030 that number is expected to reach 40 million.

Colleges and universities are taking notice, according to Challenger, Gray & Christmas Inc., a job placement consulting group.

Many have introduced specialized degree programs in eco-commerce, environmental accounting, green and social marketing, and ecological economics.

"The demand for 'green-collar' jobs is really exploding, especially as the cost of energy continues to climb," said John Challenger, the group's chief executive. "Students need to start thinking about developing skills that will give them an edge for these types of careers that did not even exist until recently."

Popular jobs include urban planners, forestry professionals and environmental lawyers, Challenger said. There is also a growing demand for architects and engineers with Leadership in Energy and Environmental Design (LEED) certification from the U.S. Green Building Council, a Washington, D.C.-based non-profit.