> only ~20-30% of the energy in the fuel turns into useful work, while electricity is much, much more efficient. So, we need much less of it.

Isn't a lot of energy used for heating, not work?

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ZeroGravitas 2 hours ago | parent | next [-]

Yes but by a weird coincidence most of that heat can be provided by heat pumps at a similar 3-5x ratio.

	▲	inigyou an hour ago \| parent [-]
		(it's not a coincidence, it's the exact opposite formula. You can only get 20% out of a certain heat engine because running it in reverse would be a 500% efficient heat pump, and the closed loop can't be more than 100%. This still applies even if the engine isn't built to be able to act as a heat pump, because some other engine could.)

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bluGill 2 hours ago | parent | prev [-]

Maybe, but that other 70-80% is waste - we could turn it into useful heat, but instead we vent it to the environment.

I've seen plans to run an engine in your furnace, thus creating both electric (at 20-30%, and capturing the rest as heat to the house. I've never seen this in the real world and experts who have looked as those systems said they won't enter a building that has one using that design. (it is possible to make a design they would trust, but they haven't seen any)