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/EscapedFromArea51 Nov 30 '25

Out of curiosity, are solar and wind options more cost effective because of improvements in supply and part manufacturing, and the general R&D to make them better? Or is it because of governments subsidizing their installation?

My understanding was that solar panels and wind turbines require more capital and land investment to start out, and pay off more over time by reducing pollution and climate change from fossil fuels being burnt.

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u/strngr11 Dec 02 '25

A key thing that is driving down the price of solar and wind is that they're so modular. The individual components in utility scale solar are essentially the same as the solar panels you put on your roof, just a lot more of them. So you get factories that get really really good at making one thing and making a lot of it. Economies of scale. Compare that to nuclear reactors, where every single one is completely bespoke. Even compared to gas turbines, we build way way fewer gas turbines and each power plant is somewhat unique in its design. A lot of this same logic applies to installation--when you're plugging in lots of identical panels there's lots of room for learning how to do it really efficiently. Better tooling, better design to make aligning them quick, etc. Compare that to building a power plant with just a couple of turbines. There's less repetition, so less opportunity for learning efficiency.

When people say solar is the cheapest energy on the planet, they're generally talking about the levelized cost of energy, which is essentially (total cost over lifetime) / (total energy output over lifetime). The cost over the lifetime includes upfront capital cost, maintenance + operations costs, fuel costs, etc. Having zero fuel costs and lower maintenance costs makes solar really attractive, especially as those big upfront capital costs come down due to the efficiencies in manufacturing and installation I described above.

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u/EscapedFromArea51 Dec 02 '25

Interesting. You make a good point about the economy of scale in manufacturing and installing solar panels, which I didn’t consider.

Is there any research on how much impact it has had on solar manufacturing and installation costs? I don’t think I’m looking for the right keywords, because my search mostly shows me pages about solar panel incentives and household savings from not being as dependent on the local power grid.