New York ? The fledgling renewable energy industry has grown steadily over much of the past decade, adding jobs at more than twice the national rate, according to a Pew Charitable Trusts study released Wednesday.

Solar and wind-power companies, energy-efficient light bulb makers, environmental engineering firms and others expanded their work force by 9.1 percent from 1998 to 2007, the latest year available, according to Pew.

The average job growth in all industries was 3.7 percent during the same period.

The entire energy sector has experienced growth in recent years as well, according to the Bureau of Labor. Bureau data shows coal mining jobs jumped 16 percent from 2003 to 2009. Oil and gas extraction jobs jumped 28 percent.

The Pew study does not include employment data from the past 18 months, a volatile period for the energy industry.

Since the data was collected, the government has said it would pump billions into renewable energy and efficiency programs.