I got curious about the current Solar PhotoVoltaic Cell electricity production in California, so I found this:
http://content.caiso.com/green/renewrpt/DailyRenewablesWatch.pdf
http://www.caiso.com/market/Pages/ReportsBulletins/DailyRenewablesWatch.aspx
This is off their main status page here:
http://www.caiso.com/outlook/SystemStatus.html
Just for April 30, 2015:
22GWh was steamed sewer (filtered sewer dumped into the earth where it heats up and shoots out as steam and generates electricity).
22GWh was wind.
48GWh was PV (solar cells).
18GWh was mirrors (4), water gravity small scale (4), biogas (4) and biomass (5) -- I think biogas+biomass were polluting, so that's 9GWh that was polluting.
This totals to "112GWh was Renewables".
Soap box: Their definition of Renewables excludes an additional ~30GWh or so of water gravity (large scale, like Hetch Hetchy). It would be closer to 40GWh if there was more water, I gleaned from 5 seconds of reading, scarce because of lower snowfall. So, there's the political: they consider ~30GWh of renewable water gravity (dams) as "non-renewable" and "bad" for us (Sierra Club wants to close Hetch Hetchy), but they consider 9GWh of biomass burning and biogas burning as "renewable" even though it is toxic. Sierra Club is one of the most anti-environmental organizations in existence; they hate nuclear power (even though it is very good for environment), they love illegal aliens (who are very bad for environment), they burn forests (which is very bad for environment), they support water policies that don't raise the price of water and keep overpumping the groundwater (which is horrible for the environment), and they vehemently oppose desalination plants (which would be great for the environment if they were built right). Sierra Club is the worst thing to happen to our environment in the last quarter century. Off soap box.
48GWh of PV created yesterday amounted to 7% of our total electrical grid use (676GWh) yesterday.
If you look at those graphs, you'll see the mismatched valleys and peaks that need to be shuffled around better. Tesla's battery packs are supposed to even those out so we could go, say, 100% PV solar cell + other nonpolluting renewables and not need any more of the other polluting sources of energy. We could even appease some of the wacko heads by moving away from good stuff they religiously hate, like nuclear power and dams. We could keep going and power all the transportation that is currently very polluting. And we could keep going even further and build enough desalination plants to water all our farms, forests, fisheries, rivers, estuaries, cities, suburbs, lawns, golf courses, pools, showers, jacuzzies, fountains and all the rest of our water desires, all powered by solar cells, if we want (even if it means we have to learn how to pre-filter the salt water through the ocean floor first to avoid sucking in wildlife). This means we can have our cake and eat it too -- as a prior poster said, Tesla is enabling us to appease both the bottom-line death-before-expenditure bastards and the "enviro"nut nazis at the same time, while meeting in the middle to do something we actually need. This is awesome! And for all my ballyhooing about how nutty the Sierra Club people and short sighted the bottom-liners are, they play an important role in tugging at us reasonable people in the middle to do sort of the right thing, and I think it will all come together because of (and in spite of) it all. And polite people could do the right thing without having to be impolite like I have been (sigh).
We have a long way to go, but just looking at what we've accomplished so far leads to a lot of optimism. I encourage everyone to go the right direction and not wait around for others to do it for us.