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by bluGill 50 days ago
Maybe, in the best case, your gas engine is maybe 45% fuel efficient, but realistically, you're probably getting closer to 20-25%. By contrast, a combined cycle power plant gets over 60%.

But that's assuming we're just running power plants off of petrol and fuels. Coal is much cheaper than petroleum in some cases. There's also a lot of people who get their power from nuclear, hydro, solar, and wind. In many cases, your electric prices are not at all affected by the increases in petrullium prices, because most of your electricity is coming from something else. In fact, I doubt there's any place in the world that all your electricity is coming from petroleum fuels. Even if that's the major input, there are almost undoubtedly other sources in the mix.
2 comments
rsynnott 50 days ago
FWIW, I don't think there are any oil or coal power plants left in the UK. Certainly none in general operation.
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philipallstar 50 days ago
> By contrast, a combined cycle power plant gets over 60%.

Over 25% of this is then lost in transmission and distribution[0] (down to 45%). Then 10-25% of that lost in charging the car[1] (down to 40%). Finally, the car itself loses about 10-15% of that[2] (down to 35%).

[0] https://www.statista.com/statistics/322834/transmission-dist...

[1] https://go-e.com/en/magazine/ev-charging-losses

[2] https://evreporter.com/understanding-the-complete-efficiency...

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hgomersall 50 days ago
Total UK electricity consumption is around 300 TWh annually. That would put the grid losses at less than 10% based on your link. The charging is never as bad as 25% (internal house losses are negligible for any sensible charging rate) and the car is typically ~12% charging loss. Moreover, EVs recover quite a bit too. Even in purely dissipative driving (highway driving), I get around 4 miles/kWh, which is about 4 times better than an ICE vehicle.

Furthermore, if you're going to include distributional losses, then let's also drop the available petrol by 10-15% to account for refining etc.

Finally, on anything resembling a sunny day, my car charges entirely of rooftop solar, so what efficiency do we assign to that?

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0cf8612b2e1e 50 days ago
That first chart is in absolute units, not percentage.

25TWh annual distribution losses off of ~300TWh usage per year is 8% loss.

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philipallstar 49 days ago
Oh! Sorry, yes. @dang can I edit it, please?
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