I haven't really been following the California peak capacity figures since the crisis eased last year, so I'm not sure how much reserve you have today. It varies by season, of course, but I think it's still low, less than 10%.
I did note, though, that California's population (according to state estimates) is projected to increase to 46 million people by 2020, up from 34 million in 2002. All things being equal, that means that you have to increase your supply by 25% in the next 17 years, just to stay dangerously thin.
How in the hell are you going to do it, since you can't build any more Shasta or Oroville dams?
LOL! Well we do have enough energy in excess fuel in our forests to make that difference on a sustainable basis. I don't suppose you knew that there is enough excess fuel in the 190 million acres of National Forest currently at risk of catastrophic fire to produce enough power to meet the residential electricity needs of 140 million Americans (with zero net added carbon). Of course, distribution would be a problem... Oh well, so much for the Wildlands Project!
Realistically, the only way we could make that kind of a change in production capacity is to simultaneously go nuclear and install micro-generating capacity for residential use, and do it in a damned hurry too. The latter seems to me more doable although fuel distribution is a problem. I agree with you, we are in a world of hurt.
I'm not thrilled with a California of 50 million, BTW. When a state grows that fast there are a lot of voters without a clue about the issues. I liked it better at 12.