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by brookside 1270 days ago
Are you aware not using the heater does not affect fuel efficiency in an ICE car? Heaters in ICE cars take the pull existing heat from the engine.

(I'm not aware of how your hybrid is programmed, it may or may not turn the engine on sooner if the heat is on.)

Letting off the gas 100 meters before a stop light and coast that will save gas, but of course it won't be more efficient to brake for the 100 meters before a stop sign, except for regen, as you mention. And is indeed obnoxious for other drivers if you are braking way before a sign.

Hypermiling is a good idea, but it's a trap to to slip into an orthorexia-type mindset about efficiency - imbuing virtue into deprivation. Going to "great lengths" to not turn on your car's heater, in addition to being 100% pointless if your ICE engine is running, is an asshole move if other people are in the car. I think it's worth it to fight the feelings of superiority you allude to in your last sentence.

I say all of this as somebody who thinks 95% of drivers would be best served by a Prius or Leaf.

2 comments

> Are you aware not using the heater does not affect fuel efficiency in an ICE car? Heaters in ICE cars take the pull existing heat from the engine.

It does in many hybrids, particularly those that can operate in EV mode at higher speeds. When heat is commanded, they often will idle under even under no load conditions just to maintain coolant temp. These are conditions which otherwise would use zero fuel.

A fun party trick in my hybrid is that I can turn on and off my engine during the winter at a stop light by using the on/off switch for the climate controls. It’s instantaneous.

Seconded by a plug-in Prius owner.

Sadly the climate control pre-conditioning on the PiP only uses the battery (or mains, if left plugged in) to cool the interior before you set off, not to heat it. I guess this is because it doesn’t have reverse cycle AC, so can’t pump heat into the interior, only out of it. Far less useful in the UK than California.

So if you want heat, you have to run the engine.

Turning on the heater reduces my electric miles by a factor of 3. More energy is spent on heating than on moving.

> I think it's worth it to fight the feelings of superiority you allude to in your last sentence.

In every other thread about climate, people hyperventilate about the doom of climate change. But when I try to do my part, it's "100% pointless" and is characterized as merely wanting to feel superior?

This to me sounds like people want to be cynical while at the same time not wanting to do anything about it.