If you check the figures in the link below, for 2013, only 4.3% of the electricity consumed in California was generated using coal, and that number included the electricity purchased from out-of-state sources. If you looked ONLY at the amount produced by burning coal INSIDE of California, it only comes to 0.3% of the power consumed.
And if you look at power from renewable sources (hydroelectric, geothermal, biomass, wind and solar), that accounted for over 20% of the power consumed in 2013.
As for 2006, the tables below shows that the power generated from coal-fired plants INSIDE California accounted for only 1.3% of the power consumed that year. That year, renewable sources accounted for 24.5% (the reason for the drop from 2006 to 2013 was almost entirely due to reduced availability of hydroelectric power due to the drought conditions these past few years but wind and solar have ramped-up during the same period, providing for 3 times as much capacity in 2013 as it did in 2006).
http://energyalmanac.ca.gov/electricity/electricity_generation.html
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