Power costs vs. uses

Power costs vs. uses

Is the billed KW from home charging the same as the used KW recorded in the car? is there line loss and charging loss to be factored in to the actual costs?

David Trushin | 5 May 2013

As far as I know, the car only tells you the electricity used during driving. It does not include loss while standing or inefficiency in charging. Some one on the forum has hooked up a meter and has numbers that you can examine. You might try searching with

magaulin | 5 May 2013

Thanks found it looks like anywhere from 20% to 30% charging and vampire loss is to be expected. That's a big hit.

dortor | 5 May 2013

I have a meter on my charging circuit - I'm seeing anywhere from 65 to 80 % charging efficiency - it depends on vampire loss and other factors but at $0.18/kwh it's coming at to be about 20% less than my ICE monthly fuel bill - and unlike an ICE it costs me $$$ to leave it parked doing nothing - go away for a week come back and have to fill it up again.

It's still good to drive, zero emissions, and gets me a car pool sticker. But I no longer believe it's much cheaper than an ICE fuel wise give my observed electrical use in two months and 5000 miles - it will probably be cheaper overall given lower maintenance costs

Brian H | 5 May 2013

The loss while standing is reflected in available miles the next time you start.

David Trushin | 6 May 2013

Yes, but not in the kwh on the trip meters. I found that i went from 6 fillups per month to one. That'a savings of 200 on gas for an additional 50 on electricity. Tbs, i didn't buy the car for the gas savings. I just don't like oil.