When looking at hat kind of graphs, it's good to keep in mind that burning hydrocarbons is relatively inefficient: 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.

Still a long ways to go regardless, but much less bleak. And also, exponentially growing deployments of wind and solar are harder to spot on this 2-year old graph which goes only up to 2024.

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bluGill 3 hours ago | parent | next [-]

That is very much a it depends. The best combined cycle power plants get around 60% efficient. The gas engine in your car is in the ideal case around 45% efficient - but the way you drive in the real world is only about 20-30% efficient.

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ben_w 3 hours ago | parent | prev | next [-]

Indeed. That exponential has renewables being ~100% of electricity in the early to mid 2030s, and approximately ~100% of all power in the late 2030s to early 2040s even without the efficiency improvement from direct electricity use.

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foota 2 hours ago | parent | prev | next [-]

> 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)

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Veedrac 3 hours ago | parent | prev [-]

They account for this.

> Primary energy is based on the substitution method and measured in terawatt-hours.