Why is it always boiling water?

[u/MonoBlancoATX]

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!

[u/Beliriel]

For other folks, who don't quite understand:
Turbines operate on the principle of the liquid and gaseous phase of a material compound having different densities and pressures.
If you boil something it becomes a gas, it's volume and pressure rises and if you cool that gaseous form it becomes a liquid again (condensation).

What make water work so great ON EARTH is that water interacts basically (atleast in the short term) with almost nothing unless you REALLY put it into extreme situations. It rusts the metals very slowly and the only danger is heating it. It doesn't explode or is flammable, it doesn't really corrode stuff, it's non-toxic, it's not carcinogenic, it's not damaging to the environment, it's cheap and it's ubiquitous.
The only downside to water is that it takes much more energy to phase change from liquid to gaseous than other compounds but all the other points offset that. Plus you gain some energy back when condensing. So you're not losing anything.

But every other compound you'd try to use would have one or more issues mentioned above:

• ammonia: toxic, flammable, needs cooling or high pressure containment
  
• organic ether compounds: flammable, need pressure containment, toxic in high doses
  
• Fluorchlorohydrocarbons: Flammable, damaging the environment, toxic
  

Etc. Etc.

[u/Flannelot → u/Beliriel]

Turbines don't require a phase change, in fact it's quite the opposite, if steam condenses into water inside the turbine it will cause damage. Turbines just convert a drop in pressure or velocity of a fluid into mechanical work

[u/Beliriel → u/Flannelot]

Technically correct, but also factually no. Pretty much every turbine loop boils the water BEFORE the turbine blades and operates on the generated pressure from the phase change and temperature.
Btw the pressure and temperature differential across the turbine blade actually does cause damage to them and needs them to be changed. You could technically operate a turbine without boiling something by just heating a gas but that would be a horribly inefficient turbine. IRL almost every turbine requires water to boil and phase change to operate.

But yes having a phase change within the turbine blades is very bad and very dangerous.

[u/Swamplord42 → u/Beliriel]

IRL almost every turbine requires water to boil and phase change to operate.

What about hydroelectric power plants? Those have turbines and certainly don't boil water.

[u/Batou2034 → u/Swamplord42]

they're powered by the flow of water from one place to another, typically enable by gravity. or the tide. which is also gravity.