Why not nuclear power?

[progree]

13. Why the massive cooling is needed

Last edited Mon Sep 23, 2019, 12:25 PM - Edit history (4)

Because of the high pressures to get reasonable efficiency out of the steam turbines we need MASSIVE containment buildings, massive amounts of water (usually near large bodies of water) and massive cooling towers.

No, that's not why they require massive amounts of cooling and containment buildings and all that. Coal-fired plants operate at higher temperatures and pressures for example. Today's conventional nuclear power plants operate at lower temperatures than coal-fired or oil-fired steam thermal power plants because of maximum safe temperature limits of the nuclear fuel rods (only about 1000 deg F IIRC -- much above that and they melt).

Late edit 9/23 1202p ET - well, both conventional (LWR nuclear) and coal-fired plants need massive amounts of cooling and massive cooling towers. But conventional nuclear power plants don't need massive containment buildings (I'm assuming you mean the big thick containment domes) because of their low temperature high pressure operation normally. Coal-fired power plants don't have containment domes. I don't think the regular builidings housing MSR plants would be much smaller than that for coal-fired plants producing the same total MWe. Nor compared to LWR nuclear, if we weren't worried about steam explosions from runaway fission, or hydrogen explosions, or other sizable radioactive material leakage accidents --it is these nuclear accident scenarios that necessitates the containment domes.

I've had nuclear Navy training and experience, as well as about 15 years as an electrical engineer in the planning and generation operations area of an electric utility. I've also read gobs of nuclear magazines (I forget the titles) and books. I'm a bit rusty though, it's been about 30 years or so since I was immersed in that.

The reason for the massive amount of cooling -- both today's nuclear and coal- and oil- fired thermal plants require them, is that any thermal engine -- one that converts heat into motion (the spinning of the electric turbine-generator) -- is limited in efficiency by the difference between the heat source and the heat sink.

http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/carnot.html

Coal-fired and oil-fired plants need almost as much cooling as conventional nuclear power plants. Not quite as much because they operate at higher temperatures than nuclear, thus having somewhat more thermal efficiency and thus needing a little less cooling per megawatt of electricity generated. The largest coal-fired power plants are like about 40% efficient, whereas nuclear are about 35% efficient (well, Wikipedia below says 30–32%). Meaning the other 60% and 65% (or 70%) of the heat produced from the fuel must be cooled away.

https://en.wikipedia.org/wiki/Thermal_power_station#Thermal_power_generation_efficiency

The containment domes are thick to withstand hydrogen explosions, and steam explosions from possible run-away fission, not because the pressures are so high normally. Again, conventional coal-fired power plants operate at higher temperatures and pressures, but don't have more than ordinary buildings to contain them (not thick high-pressure-withstanding domes).

But yeah, any thermal power plant that operates by boiling water into steam and spinning the turbine-generator with steam is going to be quite limited in its thermodynamic efficiency and thus generate a lot of waste heat that has to be removed by massive cooling towers using massive amounts of water.