I compared 11 electric-only vehicles and 11 plug-in hybrids for cost per mile on electricity (for electric only) and cost per mile on electricity versus cost per mile on gasoline. I did this at various prices per KWH and prices per gallon.
What's interesting (and infuriating) is that about two miles away from me is another city that doesn't use a for-profit utility, but that has a municipally owned power company. They charge about 11¢/KWH (Silicon Valley Power). I pay about 32¢ per KWH (PG&E).
Bottom line is that until gasoline is over $4.65 per gallon there's no point in plugging my wife's Prius Plug-In. But someone in Santa Clara should plug in as long as gasoline is more than $1.65 per gallon.
Unless you have free or low-cost electricity, the big advantage of plug-in hybrids, or all-electric, vehicles, in California, are those beautiful stickers that go on your bumpers that allow you to use the carpool lanes with only one occupant in the vehicle. Actually they have stopped issuing the stickers for the plug-in hybrid vehicles as they reached the limit, but of course the vehicle manufacturers were able to push through a bill expanding the number again.
Spreadsheet is at:
or if you're scared of TinyURLs, use .
Let me know of any errors. The data is not always easily available. Especially the real battery capacity versus the rated capacity of the battery pack if it were charged all the way (which vehicle manufacturers don't do).