If you live or have an office in SF, my understanding is that you have PG&E. At least once per decade for several decades, there have been impassioned efforts to implement municipal power in SF, to transfer all of the PG&E assets and staff to SFPUC - not easy to implement perfectly, but an equitable goal.
Now that I've left SF after living there most of a decade, and I live in the east bay, I think it's also a concern that SF gets to own a power source so far away, because of the historical timing of when it was implemented.
The SF Bay Area's intertwining municipalities are a major impedance to certain types of progress, but I also think they are a valuable alternative to a region like NYC where you have a massive city with areas that aren't really like one another.
Anyway, my understanding is that the water power plant supplies muni and other SF public purposes, such as possibly some street lights. I know, though, when I lived in the TL, and we had a power outage, the street lights would go out, so this may all flow together and be metered, rather than be separate, redundant systems.
