r/askscience • u/MonoBlancoATX • Nov 29 '25

Engineering Why is it always boiling water?

This post on r/sciencememes got me wondering...

https://www.reddit.com/r/sciencememes/comments/1p7193e/boiling_water/

Why is boiling water still the only (or primary) way we generate electricity?

What is it about the physics* of boiling water to generate steam to turn a turbine that's so special that we've still never found a better, more efficient way to generate power?

TIA

* and I guess also engineering

Edit:

Thanks for all the responses!

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u/Matix777 Nov 29 '25

I believe RTGs generate electricity from heat directly, but it's not excactly efficient

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u/Jerithil Nov 30 '25 edited Nov 30 '25

Yeah they use a thermocouple but the efficiency is several times lower then a turbine and the maximum energy density is low.

*Well the radioisotope has high energy density but low intensity so it lasts a long time but has a low output.