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Solar power crashed its way onto the U.S. power grid last year and is now fundamentally changing the makeup of how energy is being produced and consumed. Essentially, it’s becoming a mainstream power source: According to a new report from the Solar Energy Industries Association and GTM Research, solar power had another record year in 2013, with 4.75 gigawatts of solar energy systems installed, including 2 gigawatts in just the fourth quarter alone.

That made solar the second largest source of new electricity generation in the U.S. last year, only behind natural gas. New natural gas made up almost half of the new electricity built out, solar made up about a third of new electricity, and wind delivered about 7 percent of new electricity. New coal power only made up 10 percent of the total (high-fives!).

The amount of solar installed last year was 41 percent higher than in 2012. There are now over 12 gigawatts of solar panels installed in the U.S. — from 440,000 solar panel systems — and 918 megawatts of solar thermal power. Solar thermal power uses the sun’s heat to generate electricity in contrast to solar panels which convert sunlight directly into electricity (see the world’s largest solar thermal plant Ivanpah).

The rate of growth in solar has been dramatic. More solar has been installed in the U.S. in the last 18 months than in the last 30 years, says the report. California was responsible for half of the solar systems installed last year in the U.S.

The researchers behind the report are forecasting slightly slower growth, at 26 percent, for this year, which would bring the amount of solar installed in 2014 in the U.S. to 6 gigawatts. If solar installations hit that target there will be just under 20 gigawatts of solar power in the U.S.

Some other interesting data points in the report include:

The market value of all solar panel installations completed in 2013 was $13.7 billion.

Weighted average solar panel system prices fell 15 percent in 2013, reaching a new low of $2.59/W in the fourth quarter.

There were 140,000 individual solar installations in the U.S. in 2013.

Q4 2013 was by far the largest quarter ever for solar panel installations in the U.S. with 2,106 MW, up 60 percent over the next largest quarter (Q4 2012).