California’s strategy to push hard for renewables, may have backfired horribly this week, as its system operator CAISO, instigated a series of rolling blackouts to avoid its grid running out of power. By denying 200,000 to 250,000 customers power, CAISO may have spelled out the difficulties of shifting to a renewables based grid – either investment must be made up front – so that it should have built its huge battery energy storage systems two years ago, or dispatchable reserves need to be kept online until such reserves are installed. The cause was a heatwave reaching 38 degrees (100 F) triggering huge uptake of air conditioning, driving electricity usage above the 45 GW mark repeatedly, as compared to 35 GW…