3 ms·

> which in turn makes reactors difficult to run at maximum rates, due to reactor cooling issues. It's due to administrative fish protection issues. Cooling a 3

> which in turn makes reactors difficult to run at maximum rates, due to reactor cooling issues. It's due to administrative fish protection issues. Cooling a 375°C reactor with 40°C water (or even 60°C) is not a big problem. Keeping water temperatures below fish protection discharge limits set decades ago is harder. In heatwaves, the authorities relax the fish laws. https://www.world-nuclear-news.org/Articles/Heatwave-forces-temporary-change-to-water-discharg https://www.world-nuclear-news.org/Articles/Heatwave-forces-... As other commenters say, the big issue right now has to do with outages for checking a corrosion issue.

_ph_ 4y ago
And of course to buy new fish after the heatwave.
- acidburnNSA 4y ago
  Fish have become more accustomed to higher temperatures as well through the years so that kind of rule should be continuously re-evaluated and adjusted in a changing climate, as appropriate.
  - _ph_ 4y ago
    Thats not how biology works. With sweet water, oxygen supply is the killer at high temperatures, and as soon as more than a few fishes die, a cascade reaction is triggered. Yes over centuries, more resilient species might emerge, but short term, life in a body of water can just collectively die. There are very frequent events in the summer, where small lakes completely die, if the point of no return is crossed.
Fiahil 4y ago
didn't that only apply to open circuit cooling, rather than the closed circuit cooling that you would expect in most reactors ? > The precise situation depends on the reactor. But in general terms, water is either returned directly, which is known as an open circuit, which can lead to general downstream river temperatures increasing several degrees, or the water is returned after cooling in air-cooling towers, known as a closed circuit, which typically leads to lower rises of downstream river temperatures, of a few tenths of a degree.
- b3orn 4y ago
  A lot (not all) of cooling towers still require water for evaporative cooling. And the restrictions aren't just for temperatures of returned water they're also for the amount of water taken from rivers, during droughts that amount might get reduced quite a lot.

_ph_ 4y ago

And of course to buy new fish after the heatwave.

acidburnNSA 4y ago
Fish have become more accustomed to higher temperatures as well through the years so that kind of rule should be continuously re-evaluated and adjusted in a changing climate, as appropriate.
- _ph_ 4y ago
  Thats not how biology works. With sweet water, oxygen supply is the killer at high temperatures, and as soon as more than a few fishes die, a cascade reaction is triggered. Yes over centuries, more resilient species might emerge, but short term, life in a body of water can just collectively die. There are very frequent events in the summer, where small lakes completely die, if the point of no return is crossed.

Fiahil 4y ago

didn't that only apply to open circuit cooling, rather than the closed circuit cooling that you would expect in most reactors ? > The precise situation depends on the reactor. But in general terms, water is either returned directly, which is known as an open circuit, which can lead to general downstream river temperatures increasing several degrees, or the water is returned after cooling in air-cooling towers, known as a closed circuit, which typically leads to lower rises of downstream river temperatures, of a few tenths of a degree.

b3orn 4y ago
A lot (not all) of cooling towers still require water for evaporative cooling. And the restrictions aren't just for temperatures of returned water they're also for the amount of water taken from rivers, during droughts that amount might get reduced quite a lot.