Here's the California Independent System Operator (CAISO) data that shows the share of different energy sources over the course of each day: http://www.caiso.c

Here's the California Independent System Operator (CAISO) data that shows the share of different energy sources over the course of each day: http://www.caiso.com/todaysoutlook/pages/supply.aspx http://www.caiso.com/todaysoutlook/pages/supply.aspx Power is being exported in the afternoons, but even at that time natural gas plants continue to run.