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This is such a misleading comparison. The energy used that comes from a solar panel is already in an extremely low-entropy, highly usable form. The energy used from a fossil fuel is highly inefficient and hard to harness.

For instance, if you just go by the number of joules in an electric car's battery versus the number of joules in a gasoline car's tank with the same range, you'll see that a 'normal' electric car gets around 15 kWh/100km whereas even a rather efficient gas car needs something more like 50kWh/100km. That's because gas combusion loses gigantic amounts of energy to heat and sound.

If you want to talk about 'total energy consumption' and compare solar/wind against fossil fuels, you should count the amount of energy in the sunlight that hits the surface of the solar panel, or the amount of wind energy hitting the turbine blade, rather than the amount of energy they deliver to the grid.

by ragebol4 hours ago|

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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.

by bluGill3 hours ago|

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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.

by ben_w4 hours ago|

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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.

by foota3 hours ago|

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> 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?

by ZeroGravitas2 hours ago|

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

by inigyou1 hours ago|

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(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.)

by bluGill3 hours ago|

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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)

by Veedrac3 hours ago|

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They account for this.

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

by afarah14 hours ago|

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Also interesting to look at the chart per country. [2] US fossil fuel is 4x entire Germany, while for China just coal is over 8x all of Germany. So good and relevant news at a local scale! But pretty irrelevant at a global one... A scale at which there is more talk than action in parts of the world, probably because it would be too economically painful if not unfeasible to e.g. limit or tax imports, outsourcing etc by emission source.

[2] https://ourworldindata.org/grapher/primary-energy-source-bar...