For ten minutes this afternoon (around 1:10pm on March 30th, 2014) electricity created from non-large hydro renewable sources (solar, wind, geothermal, biomass, biogas, small hydro) equaled 8202 Megawatts, or 37.7% of California's total utility electricity demand. This, I believe, is a record.
This by and large doesn't include renewable production "behind the meter" such as rooftop solar. It is likely rooftop solar produced another 3000 megawatts or so. (Rooftop solar generally shows up as reduced demand.)
Now this was just for ten minutes. It is likely over the course of the day renewables will be equivalent to only 20% or so the day's electricity demand. (Edit: it turns out on March 30th renewables fed into California's utility grid were equivalent to 25% of the day's 24 hr electricity demand.) But to put this 8202 megwatts in perspective, 30 states in the US averaged less than 8000MW/hour of electricity consumption in 2013. Of course all those states have much lower populations than California. However, California had the lowest per capita electric consumption of the country last year, followed closely by Hawaii. (Climate has a lot to do with it.)
Both California and Hawaii significantly dropped their per capita electricity consumption from 2012 to 2013, California by 2% and Hawaii by nearly 2 1/2%, due to a combination of efficiency measures and increased rooftop solar.Very little wind power was added in California last year, but a heck of a lot of utility scale solar went on line in the 4th quarter of 2013, and we're seeing the results now.
If you're interested in tracking California's renewable electricity production, follow this link. Another fun link is Denmark's real-time electricity production graphic, complete with little turning windmills.