Solar power plants, of course, rely on the sun to produce power. Solar power output depends on the intensity of the sun and varies depending on the hour, the weather, and even the season. The further a solar power plant is located from the equator, the more the seasonal variation affects the output. Solar power plants in northern areas in summer experience more direct sunlight, producing more power. Winter sun is not as direct, and so solar power plants produce less power.
In August, California just passed one giga-watt [1GW] in solar power-generating capacity, pretty impressive considering that eight months earlier, December 2011, there was just 200MW, or 0.2GW, solar power capacity. California’s solar power capacity has only grown since then, leading to a record-setting day in the middle of winter.
The the days surrounding the winter solstice are the shortest and least-sunny days of the year, and wouldn’t be the time to expect record-setting solar power generation. California Independent System Operator [CaISO], operator of California’s transmission grid, recently released the numbers for power generation on December 19, 2012. In the middle of winter, for three hours, California’s solar power output maxxed out between 950kW and 1,000kW.
“On Wednesday, December 19, the CaISO’s preliminary figures for renewable energy output, which are displayed in the chart at the top of this post, indicated that for Wednesday’s solar output reached a peak somewhere between 950 and 1,000 megawatts at around 10:30 am, and held there until just after 1:00 pm,” said a KCET commentator. One gigawatt isn’t much in the overall scheme of things, but points toward California’s commitment to renewable power generation, including solar power.