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throw-qqqqqlast Monday at 4:20 PM2 repliesview on HN

> That's because a) some batteries suffer degraded performance at low temperature, and b) ICE cars use the plentiful waste heat for cabin heating whereas an EV needs a heat pump or even resistive heating of the cabin air.

You are making my point here actually. Combustion engines suffer from the exact same, but because they waste so much energy as heat already, less “extra” energy needs to be spent on that.


Replies

mort96last Monday at 9:39 PM

I don't think there's a contradiction here. Electric cars suffer degraded range when it's cold (in part) because they're so much more efficient that they don't produce enough waste heat to heat the cabin. And batteries are so much less energy dense than diesel and gasoline that the extra power draw reduces their range to a meaningful degree.

Dylan16807last Monday at 9:58 PM

Part of your point is right, part is wrong.

Yes heating impacts range in an EV, but it's not really an efficiency thing, it's because you can't get it "free". If an ICE didn't let you harness the heat, you'd see a similar percent drop in range.

And for extra weight, it's just not true. Making a motor work 10% harder at 90% efficiency, compared to making an engine work 10% harder at 20% efficiency, both of these are going to reduce your range by 9%.