While this is certainly a major milestone, California’s peak demand on Jan 10 was 31.5 GW. 1 GW of solar power is thus theoretically about 3% of the total amount of power needed, except of course, solar doesn’t generate 24/7 so the actual amount of produced solar power will be substantially less than its potential.
As you can see, wind produces far more renewable power that solar. Big hydro dwarfs them all but inexplicably isn’t considered renewable energy by California. How weird is that? certainly big dams can be environmentally destructive but virtually all the locations in the US for big hydro were built decades ago, so why not include it?
California is pushing hard for rooftop solar power, which is a great idea, and I hate to be a wet blanket, but 31.5 GW of peak demand will never ever be met by rooftop solar. During the summer peak demand in California can be more like 75 GW. California plans 33% in-state renewable energy by 2020. We got a long way to go and a short time to get there, especially considering the big hydro behemoths, the Hoover and Grand Coulee Dams, are in other states, as are wind and solar farms that send power to California - and none of them will be allowed to be part of the 33% number.