>Data for 2016
This lists California at $0.15/kWh. I've never paid even close to that anywhere I've lived.
The current PGE residential rate of $0.28/kWh [0] is about the same as Honolulu, Hawaii, where 100% of electricity is produced from burning natural gas and petroleum.[1]
[0] https://www.pge.com/tariffs/electric.shtml
[1] https://www.hawaiianelectric.com/billing-and-payment/rates-a...
My PG&E's lowest off-peak rate is now 16c, though I'm on a TOU plan and just installed solar, and I have generation through Peninsula Clean Energy so my bill is somewhat more complicated than the charts involved to send Apollo 11 to the moon.
If you mean Silicon Valley Power, the municipal electric utility for Santa Clara, it's now (as of Jan 2017) 11.82c [1] for residential non-TOU for the upper tier.
It's also only for the city of Santa Clara. Palo Alto has a municipal utility, but its rates are higher, and these are exceptions. AFAIK, the vast majority of California is served by a private utility (e.g. PG&E).
[1] http://www.siliconvalleypower.com/home/showdocument?id=6253
Also California isn't most expensive, seems pretty much the same as many blue states. https://www.eia.gov/electricity/state/