Out of the 25GW being generated right now only 3GW are renewable. There is a corner where there is more demand from "100% renewable" customers than there actually is available renewable energy. There is no point at which this gets made up.
I’m not sure where your figures are coming from, did you mean at the moment of posting your comment? If you look at the integral over the year, California does decently well[1] on renewables, and the people paying for it help blunt the competitive edge of the tremendous federal subsidies enjoyed by fossil fuels.
Technically it does decently well on combined "non greenhouse gas + renewables." This is a rather self serving categorization of generation sources and might not be what people buying "100% renewable" energy think they're actually getting.
In any case, subtracting Nuclear and Hydro, if more than half the kWh purchased in the state are purchased as "100% renewable", they cannot all be possibly served by renewables even in the aggregate.
The first is that at any given point in time, my instantaneous energy use is offset by renewables.
The second is that over some period of time (e.g., one month) my aggregate energy use is offset by renewables.
The second is MUCH easier. When people say things are 100% renewable, I generally think they mean the second thing. This is a bit of a fudge (not wrong but not 100% level).
