Solar and wind power accounted for all--that would be 100 percent--new electricity generating capacity added to the U.S. power grid in September.
Five wind projects totaling 300 megawatts and 18 solar installations totaling 133 megawatts were added in September, according to Federal Energy Regulatory Commission's Energy Infrastructure Update, which was initially reported by renewable energy analyst and SUN DAY Campaign executive director Kenneth Bossong.
This wasn't an isolated event for either renewable energy source. Solar and wind, although still trailing fossil fuels, collectively account for 40 percent of all new generating capacity added since January 2012. Include other renewable energy sources in the mix, such as biomass, geothermal, waste heat and water, and that figures increase to 43.8 percent of all new generating capacity added since the beginning of the year.
Wind has done particularly well. More than 4,000 MW of wind capacity has been added to the U.S. power grid since January, outpacing installations of all other sources of electricity except natural gas, which had 4,587 MW of installed capacity over the same time period.
Solar has seen a rise U.S. electricity generation capacity as well, albeit on a much smaller scale compared to natural gas, coal, nuclear and wind. In the past nine months, 154 solar projects have added 936 MW of capacity.
Solar and wind still have a long way to go before either energy source takes over traditional fossil fuels. According to FERC, solar accounts for 0.31 percent and wind 4.43 percent of total installed operating generating capacity on the U.S. power grid.
Meanwhile, coal and natural gas still provide the greatest share of electricity to the grid. Coal has 338.98 gigawatts of installed capacity on the U.S. power grid, accounting for 29.4 percent. Natural gas has 483.92 GW of installed capacity, accounting for nearly 42 percent of total operating generating capacity.