Solar energy in the United States is becoming a major part of the nation's power sector as installation costs decline, Energy Secretary Ernest Moniz said.

Moniz announced more than $53 million in funding for more than three dozen research and development projects aimed at driving down the cost of solar energy.

"As U.S. solar installation increases and the cost of solar electricity continues to decline, solar energy is becoming an increasingly affordable clean energy option for more American families and businesses," he said in a Wednesday statement.

The secretary said the country has 15.9 megawatts of installed solar power, enough to meet the energy demands of more than 3.2 million average households.

Moniz in early October rolled out $25 million in funding for research and development of concentrated solar power technology, which uses mirrors to focus the sun's rays onto a transfer system in such a way that thermal energy is stored around the clock.

A recent report from the International Energy Agency found solar energy resources could combine to become the world's largest source of electricity by 2050, while at the same time offsetting more carbon dioxide emissions than the United State currently puts out.