More than 3,400 companies are in the solar energy sector and employ about 25,000 to 35,000 workers, including installers, manufacturers, distributors and project developers and materials suppliers.

“We estimate that will grow to more than 110,000 direct solar jobs by 2016,” said Monique Hanis, a spokeswoman for the organization.

Solar workers install thermal collectors, which convert the sun’s rays into heat used to supply buildings with hot water, for heating and cooling systems and to warm swimming pools. They also install solar panels to convert the sun’s rays into electricity that can power things like appliances and lights. When more electricity is being produced than the customer is using, the excess can be stored in batteries for use at other times. When batteries are full, the surplus electricity can be exported back to the electrical grid if the building is connected to it, offsetting electricity costs from the utility company.

Consumers are turning to solar energy for various reasons, including, of course, the idea that solar power creates no carbon emissions. And many people feel that solar power is important in reducing the dependence of the United States on foreign oil. Some even see a roof festooned with solar panels as an ecological status symbol.

Beyond all of that, government subsidies can reduce the cost of installing solar panels.

Bob Cowen of Morris County, N.J., chose solar panels for his roof for both ecological and economic reasons. To outfit his home with 49 solar panels, he paid $64,700, minus rebates of $42,500  for an out-of-pocket cost of $22,200.