average residential electricity rate is 15.34 cents per kWh
This didn't seem right, as I pay more than double that here in San Francisco. (I calculated $0.35/kWh by dividing the total I paid for electricity generation and delivery, and dividing it by the number of kWh consumed.)
The linked page cites data from over a decade ago (2012).
That whole section is BS in general. The server linked isn't going to use 1KW of power ever, not on the worst of days. The only real point that they're making is that "it's loud" which is true, very true, but, it's designed to run in a rack away from humans..
While their solution is more livable for them, the hardware is vastly inferior for actually hosting serious services on, and they don't seem to understand that because they're software guys who're getting away with it.
Within the state, there's huge variation. The average is around 25 cents. E.g. if you live in Santa Clara, you pay 16.6 cents per kilowatt hour to Silicon Valley Power, while all surrounding cities pay 45 cents-ish.
Technically the CA government only sets a maximum price, not prices themselves. Power companies can sell at market rate if they want. But that same CA government also allows monopolies, so the price ceiling becomes the floor.
The linked page cites data from over a decade ago (2012).