The Tesla S hype has me interested. So now I’m curious,
what does it really cost to run per mile? The Tesla site has a
decent
calculator, here’s some numbers derived from it.
Tesla says they get 283Wh/mile. Electricity in San Francisco costs $0.35/kWh.
So that works out to $0.10/mile in a Tesla. Tesla
compares itself to 22 MPG cars. Gas in San Francisco is roughly $4/gal,
so it’s $0.18/mile in a gas car. By that math,
a Tesla is roughly half the cost of a gas car in San Francisco.
San Francisco has outrageously high electricity costs. At the national
average of $0.11/kWH a Tesla is more like $0.031/mile, or six times
better than a gas car.
On the other hand, batteries wear out. Tesla is offering
to replace the battery after the 8 year warranty at a prepaid
cost of $10,000 – $12,000. Assuming 12,500 miles a year that
adds $0.10/mi to the cost of driving a Tesla, dwarfing the cost of the
electricity! The Tesla ends up being $0.13 – $0.20 / mile
compared to $0.18/mi for the 22 MPG gas car
(and roughly $0.12 – $0.20 / mile for gas cars in general).
Update: Ken points out the battery lasts
another 8 years, so battery replacement really adds $0.05/mi. Our
SF Tesla then is $0.15/mi. Also
Dan asks
if some part of drivetrain maintenance should factor in to
gas car operating costs.
If you think of the battery as another form of “fuel”
that needs replacing every eight years, then the Tesla costs about the
same per mile to drive as a gas car no matter what electricity rates you
pay. But maybe the battery will last longer; no one really knows. Also,
I suspect most Tesla customers think of the battery cost as depreciation
and not a consumable.
Another argument for Tesla is that electricity is somehow more
environmentally friendly than gas. Not really; a Tesla is
metaphorically spewing 44% coal emissions
out its tailpipe. It’s 20% nuclear though, I think that’s a win.