In Hot Water: The Effects of Even Modern Nuke Plants On Water 303
Harperdog writes "Dawn Stover has a fascinating article on the newest nuclear power plant to get approval: the Blue Castle Project on the Green River in Utah. Stover details the enormous damage done by nuke plants on local water systems, and points out that the 1-2 punch of climate change and cooling systems is already taking a toll on the ability of nuclear power plants to operate, because in summer the water they use to cool systems with is too hot even before they use it (Tennessee Valley Authority is the example). "
Re:There are other options I guess (Score:5, Informative)
Point i) is a thermodynamics fail.
Re:How much would better cooling cost? (Score:4, Informative)
There are ways to cool without dumping heat into rivers and oceans or evaporating water. You could drive a bunch of Stirling Engines. You're not interested in the power from the Stirlings, just their use of the excess heat. How much would that cost though?
There are ways to cool without dumping heat into rivers and oceans or evaporating water. You could drive a bunch of Stirling Engines. You're not interested in the power from the Stirlings, just their use of the excess heat. How much would that cost though?
The need for "cooling" is a bit of a red herring. It's not strictly about keeping things from getting too hot, but about providing a sufficient temperature (and therefore pressure) differential. Such differentials would also be required to drive a Stirling Engine, and while they will function at a much smaller differential than a steam turbine, they will still have cooling requirements, otherwise they would achieve thermal equilibrium. And since Stirling engines are more useful for performing relatively slow mechanical work (you can gear them up, but gears have parasitic losses), you may well end up using more energy to create the same amount of electrical power as a steam turbine. That's just my armchair analysis, though I trust that the engineers who designed the plant have made optimal decisions in generator selection, so the fact that they're using steam turbines speaks for itself in that regard.
Almost right. (Score:5, Informative)
Water used in steam turbines is distilled water - as few particulates as possible at they will erode the turbine into junk.
The heat source heats water into steam to drive the turbines. That water is then cooled by external water before being returned to the heat source.
The external water may be pass through or recycled, but it never ever gets to the turbines.
And water really doesn't expand during heating (under 1%) until it boils and becomes vapor.
Re:There are other options I guess (Score:2, Informative)
Not a thermodynamics fail in Utah. The Palo Verde nuke plant in Arizona does OK in a desert climate. The Utah plant would be no different. Desert climate usually equates to low relative humidity, which means the evaporative cooling used in the condensers will still work, even in the peak of summer there.
Contrast that with the southeast US, where high temps *and* high humidity reign in the summer. During the drought, water levels were way lower than they were. Shallower bodies of water tend to be warmer than deeper bodies of water. The condensers there have a much harder time using evaporative cooling, if they do at all, so they try to pull in cool enough water from a big body of water next to the plant, whether it is a significant river or a large lake. Except in this case, due to the drought, high temps and low water levels, the water being pulled in simply wasn't cool enough.
Re:Should read "power plants", not "nuclear plants (Score:5, Informative)
Keep in mind those same laws of thermodynamics dictate that the larger the temperature difference, the higher the efficiency. Now, temperature isn't the same thing as heat, so that doesn't automatically put limits on small-scale operations. However, in practice it tends to do so. Generating high temperatures in a huge furnace is a lot easier than doing it in a small one, which is why a coal plant is more efficient than a car engine.
Re:But hydro power *cools* rivers, can't they offs (Score:5, Informative)
The trouble is that dammed rivers are (at least in CA) generally warmer over all (due to lower flows and a larger heating surface on the surface of the lake). Then you do a release from the dam (bottom of the lake) and dump a bunch of frigid water into the stream. Huge temperature swings for the organisms to deal with.
Re:Doesn't matter (Score:5, Informative)
Yup, the French make prolific use of cooling towers in order to reduce thermal impact on rivers.
Also keep in mind that this affects coal plants just as much as nuke plants, and will also affect combined cycle natural gas plants that use steam for a bottom cycle.
Re:Nothing is ever good enough (Score:4, Informative)
Actually, it was an endangered tortoise, not a lizard. And it wasn't shut down, the company behind it had to acquire more land to manage habitat for displaced animals.
So really, nothing actually happened to that particular solar plant. I swear, sometimes I think environmentalists are the new all-powerful bogeyman. Everything goes wrong is their fault, even the stuff that doesn't go wrong.
One source: http://energy.gov/articles/department-announces-loan-guarantee-brightsource-energy-inc [energy.gov] 2 minutes of googling finds you load more.
Re:Doesn't matter (Score:5, Informative)
Uh, no. Even if I hadn't RTFA I'd know you are wrong. Cooling towers are built to cool the water through evaporation, and said evaporation (and blowdown) of the proposed "closed-loop" cooling system is what TFA was complaining about, since none of the water taken would be returned to the river.
Also, a lot of cooling towers are built precisely to cool the used river water before returning it to the river, so, because of evaporation, they not only return less water to the river than taken, because the river is lower temperature than the typical ambient wet bulb temperature, what they return is warmer than the river (unless you had a really unusually hot river).
Re:Doesn't matter (Score:5, Informative)
Re:Should read "power plants", not "nuclear plants (Score:3, Informative)
I believe you have this backwards; not sure why you got all the positive mods.
I can trivially generate a 1000 F temperature on the end of a cigarette, but I sure can't do that to a football field.
Similarly, I can reduce the size of the chamber in my foundry and it will heat up faster, easier, and cheaper.
If you dumped a huge pile of cigarettes onto your football field, you'd find that it takes far fewer of them with less ventilation per cubic inch to heat them up to 1000F, compared to what you have to do with a single one. Sure, it does require more heat, but not more heat per unit of volume.
Heat is lost through the surface of an object - the larger an object is, the less heat it loses per unit of volume through its surface, since the former increases with the cube of size, and the latter increases with the square.
All that said, it is true that it takes a smaller heater to heat an oven than a foundry. It just takes a bigger heater per unit of volume to heat a kitchen oven.
Re:And coal doesn't? (Score:4, Informative)
Yes, since they use exactly the same process at all points past the "fuel->heat" stage. But you get more attention if you say "nuke" in the headline.