Since we are approaching the summer solstice (June 21), the longest day of the year and the official start of summer, I thought it was a good time to look at how longer days and more sunshine are translating into more clean electricity. The bottom line: solar is starting to pull its weight on the grid. Over the past six months, solar electricity from large-scale photovoltaic (PV) plants and concentrated solar thermal generation facilities in California supplied around 6 percent of the state’s electricity needs, and has jumped as high as 20 percent on particularly sunny days.
The data used for this quick analysis comes from the California Independent System Operator (CAISO), which maintains the Renewables Watch page on its website, a great source of information on how renewables contribute to the grid each day. The CAISO’s data only capture generation from large-scale projects, so these numbers don’t reflect the additional electricity generated from small-scale rooftop systems. In addition, this generation data reflect only roughly 80 percent of the California grid — all generation under the CAISO’s control. Electricity served by the Los Angeles Department of Water and Power, Sacramento Municipal Utility District, Imperial Irrigation District, and a few other publicly owned utilities is not included. So, all this means that solar generation is actually higher than what’s reported here.
California sets new solar generation record this month
California broke a new solar record on June 1, 2014, when solar production over the course of the day was more than 47,000 MWh, representing nearly 8 percent of all the electricity consumed in the CAISO region.
But it’s not enough to look at just one day’s worth of electricity. Comparing 2013 average daily generation from May 15th to June 15th in 2013 to 2014 presents another perspective of how fast solar is growing. The 2013 average daily generation between May 15 to June 15 was roughly 16,000 MWh; the same time May-June daily average in 2014 was 41,000 MWh, a 152 percent increase.
In the past year alone, more than 25 large-scale solar projects have come online, including the largest solar plant in the world, Ivanpah, a concentrated solar power tower 40 miles southwest of Las Vegas.
The growth of the rooftop solar market has been equally as impressive. California now has more than 240,000 small-scale solar installations on commercial and residential roofs across the state that amount to more than 2,200 MW of generation capacity.
But, we have just scratched the surface on solar in California and the rest of the country. Part of the opportunity inherent in solar technology, especially solar PV, is its ability to scale up and down in size and locate in both urban and rural areas. Solar power is, to a great extent, an equal opportunity renewable energy.
Every U.S. state has enough sunlight to make solar an attractive option in at least some applications. Policies that promote renewable energy investments at the state and local levels will continue to be key to helping us unlock this clean, renewable resource for our country. Stay tuned for more details about how we make this happen. This fall UCS will release a report on solar that identifies key opportunities for increased solar investments, and how we can overcome the current roadblocks we are facing to more people going solar.
Featured image: Flickr Commons, Walmart Corporate