# Range formula for an AC system?



## sailfish11 (Sep 15, 2007)

I've seen several good formulas and calculators for estimating your EV's range, but all the one's I've seen assume you're using a DC system. Does anyone know where there's a good AC system estimator? Thanks!


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## judebert (Apr 16, 2008)

The same formulas should work for AC, in general.

You can sometimes expect an AC system to be more efficient; however, it's generally a very minor difference. If you know your system is one of the more efficient ones, add a percent or two.

One major difference is regenerative braking. Not all AC systems support this, but many do. Real-world experience indicates that you can expect about 5% range improvement; less if you drive on the highway, more if you drive in the city with lots of stoplights (and you're careful about it).

The other major difference is the batteries. With DC systems, we tend to assume Lead-Acid batteries, with a high Peukert factor and only 80% max depth of discharge. AC systems often use Li-Ion, NiMH, or other advanced battery technologies. You'll have to figure out the adjustment for those on your own.

And of course, the folks at MetricMind are generally very helpful.


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## sailfish11 (Sep 15, 2007)

Ok, I guess I misspoke (mis typed?) earlier . I know about a couple range _calculators_, but I can't find a good formula. The problem with the calculators is that they don't seem to have been updated recently. Can anyone give me a link (or the formula)? Thanks!


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