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Energy Information Administration, “California drought leads to less hydropower, increased natural gas generation” (10.6.14)

• “The drought in California continues to increase in severity since California's governor declared a state of drought emergency in January 2014. As of September 30, 58% of the state was classified as experiencing exceptional drought, the most intense drought category. These dry conditions limit hydropower generation, requiring generation from other sources to make up for the shortfall. … In California, natural gas-fired capacity is often used to help offset lower levels of generation from hydropower facilities. The chart below shows how this inverse relationship can work: when monthly hydropower generation dips under 10-year average levels, monthly natural gas generation often rises above its 10-year average in response. From January through June of 2014, natural gas generation in California was 3% higher compared to the same period in 2013 and 16% higher compared to the January-June average from the previous 10 years."

Energy Information Administration, "Today in Energy, Half of power plant capacity additions in 2013 came from natural gas" (4.8.14)

• “Nearly 60% of the natural gas capacity added in 2013 was located in California. The state is facing resource adequacy concerns as well as the need for more flexible generation resources to help complement more variable-output renewable resources, particularly solar, being added to the system."
• "Solar photovoltaic (PV) added 2,193 MW of capacity in 2013, continuing the trend of the past few years of strong growth, helped in part by falling technology costs as well as aggressive state renewable portfolio standards (RPS) and continued federal investment tax credits. Nearly 75% of the capacity added was located in California, followed by roughly 10% in Arizona. (Note: these figures do not include distributed capacity under 1 MW. Distributed solar PV capacity additions also grew in 2013, with industry reports estimating nonutility additions of 1,900 MW. Most of this capacity was also located in California.)”

Energy Information Administration, “Today in Energy, California continues to set daily records for solar” (6.25.14)

• “In 2013, 2,145 MW of utility-scale solar capacity entered service in California, of which more than 500 MW came from large-scale solar thermal plants. California accounted for more than 75% of U.S. utility-scale solar capacity installed in 2013. Total solar electricity output in May 2014 constituted 6% of the total CAISO electricity load that month, compared with 2% in May 2013. However, during the average peak solar output hour, between 11:00 a.m. and noon for May 2014, solar supplied 14% of total power, compared with 6% in May 2013. Solar generation facilities generally provide power to the CAISO grid from early morning until the evening, and reach peak output around midday. When solar electricity is being generated, less electricity from other sources such as natural gas or interstate electricity imports is required. Conversely, when there is little-to-no solar generation, the shares of other fuels used in California's supply mix rise.”