WASHINGTON, D.C. — The renewable energy and energy efficiency industries stand to add millions of jobs and pump trillions of dollars in revenues during the next twenty years, according to a new research report.

"Renewable Energy and Energy Efficiency: Economic Drivers for the 21st Century," from the American Solar Energy Society, said that as many as one in four workers could work in these fields by 2030.

The industries currently generate about 8.5 million green collar jobs and almost $1 trillion in revenue, the report found. That could increase to 40 million jobs and $4.5 trillion in revenues "with the appropriate public policy, including a renewable portfolio standard, renewable energy incentives, public education and research and development," the report said.

"The green collar job boom is here," said ASES's Neal Lurie. "Renewable energy and energy efficiency are economic powerhouses."

The report predicted that solar, wind, ethanol and fuel cells will be future hot areas of growth.

The report comes a week after General Electric Power Generation announced it would invest $39 million and hire 500 workers for a renewable energy division expansion in upstate New York.

Some states, such as California, have mandated that renewables comprise a larger percentage of their energy portfolios.