A Little Arithmetic: The Costs Of A Solar-Powered Grid Without Fossil Fuel Back-up
Yesterday’s post made the point that states or countries seeking to march toward 100% “renewable” electricity don’t seem to be able to get past about the 50% mark, no matter how many wind turbines and solar panels they build. The reason is that, in practical operation, due to what is called “intermittency,” no output is available from the solar and wind sources at many times of high demand; therefore, during those times, other sources must supply the juice. This practical problem is presented most starkly in California, where the “renewable” strategy is based almost entirely on solar panels, with only a very small wind component. Daily graphs published by the California Independent System Operator (CAISO) show a clear and obvious pattern, where the solar generation drops right to zero every evening just as the peak demand period kicks in from about 6 to 9 PM.
Commenter Sean thinks he has the answer: “Given the predictable daily power generation cycle of solar in sunny places like California and the predictable daily demand which peaks in the evening perhaps solar generators should be required to have electricity storage equivalent to the daily generation of their PV system.”
