Que? Heat waves don’t trim nuclear output

As this comment (feddit.org/comment/14419698) says

In France, Hungary, Romania Nuclear Plants have shut down due to concern over ecological impact or not enough water to cool the plant

Also the jellyfish situation for one of the plants as well.

They do. What happens is that either water levels drop sufficiently enough or the temperature of the water in the rivers that they’re drawing from rises to a point that it cannot provide sufficient cooling so they have to turn down or turn off the reactor.

Interesting, thank you for the explanation!

If the water is still warm, can’t they extract that energy somehow?

This would work in winter and there are already heat pumps that use river water. Those are utility scale installations, though, so they don’t just pop up overnight. And they’ll be pretty useless in summer, when the air is hotter than the water.

Not if they don’t already have the infrastructure in place. Remember that these power stations were built 30 odd years ago. No one expected climate change to get this bad this quickly even in the most pessimistic of models.

Heat is the worst form of energy. It’s super hard to extract energy at all from it. Basically, you can’t extract energy from heat itself, you can only extract it through the process of heating something up. So you always need a cold component that gets heated up and a hot component that does the heating.

Without a cold component, you can’t extract energy from heat.

Thermoelectric is hilariously inefficient, so you can’t really use it for electricity production, once it’s served its purpose of turning the turbines.

What you can do with spill heat is to reuse it in district heating networks to provide hot water. And heating, of course, but there’s no use for that during heat waves

Nuclear energy isn’t a solution to anything. Solar and Windmills are much better, there really isn’t any argument for nuclear energy (if you want to teach me a better one, why don’t we start by building a nuclear repository in your region?).

Nuclear energy is the most energy dense form of power generation on the planet, and nothing else comes close. When fuel rods are “expended” taken out of a reactor after their 2 year cycle for the first time ~95% of the energy still remains in the rod. Chemical reprocessing can filter out the decay products and put the fissionable or fertile materials back into production.

Additionally, nuclear is one of the safest sources of power production on the planet. Disasters have occurred at places like Chornobyl, fukushima, and three mile island. And there’s a reason we don’t build reactors like that anymore. Every time an incident has occurred the rules for this power generation have been updated to ensure that such an incident can’t happen again.

As far as building a nuclear repository in my region? We are. We are are standing in the beginning of the next golden age of nuclear power.

While wind and solar are good to have for redundancy and diversity of power generation, they cannot change their generation ability easily at any point of day, during any weather conditions, regardless of external factors.

Nuclear’s global share fell from 17.5% (1996) to ~9% (2024) and is flat outside China. That’s not a golden age. Of the 63 reactors under construction worldwide, all but four are backed by China or Russia. No country has an operating repository yet, not even Finland. France had more than half its fleet down in 2022 from corrosion, and had to throttle reactors again this year from heat. And unlike renewables — ~40% of German renewable capacity is literally owned by private citizens and farmers through energy co-ops — nuclear requires the kind of capital and secrecy that only states or utilities can provide. 19 EU reactors are still fully fuel-dependent on Russia’s Rosatom right now, which bundles its reactor exports with political influence programs. That’s not a coincidence, it’s structural.

Nuclear fission is the current cleanest way of generating on demand power, assuming you aren’t able to build a water based powerplant. If done correctly they can be built in such a way that they inherently fail in a state that renders them inert. I’m not all too familiar with the process, but that last time I looked, with proper refining of spent fuel, the waste was 10% or less than the original fissionable material.

The average reactor running today is 32 years old - “inherently fail-safe” describes future designs, not the existing fleet. On reprocessing: Germany has banned it by law since 2005, so that “10%” argument doesn’t even apply to the case you’re probably picturing. And reprocessing plants like La Hague, which separate weapons-grade plutonium, are exactly the kind of high-security, low-transparency facilities that make nuclear a political problem, not just a technical one.

I was not aware that you were referring to current infrastructure, I assumed since you were talking about solar and wind, which also need more build outs, that we were talking about building new infrastructure. I also wasn’t making any judgments based on legislation, since a decent amount of their justifications are “nuclear bad”, I will grant you that it is a considerable hurdle in most places of the world. This is also why I chose not to factor in the fact that nuclear fuel is generally also very useful for weapons which is another large political hurdle. As to your point about the secrecy of the refining facilities, I personally am opposed to security through obscurity, and I cannot currently think of a reason why the facilities need to be opaque, especially considering that I believe it helps alleviate large amounts of the political issue.

“why don’t we start by building a nuclear repository in your region” really isn’t the own you think it is? Like sure? I genuinely do not think that would be a problem for my life at all

Your personal comfort isn’t consent, a repository binds an entire region for a timescale (100,000 years) that outlasts every democratic institution we have. Nobody alive can consent on behalf of the thousands of generations that timeline covers. The reason siting takes decades everywhere is precisely that “I personally wouldn’t mind” isn’t how legitimate consent works. You need actual buy-in from residents, municipalities, parliaments, not one guy’s shrug.

So why the fuck did you bring that up as your point then?

Sarcasm?

But I was told nuclear would always work, regardless of weather!

Well, at least it sounds like solar would be a great complement. Again.

Not sure if joking or just ignorance? Both?

1. The nuclear capacity losses are because of environmental regulations, not because of inherent issues with nuclear.
   • Regulations restrict discharge of cooled water above 30°C into waterways, and they are responsible for the riverway temperature downstream of them. Since the waterways are warmer during a heat wave and the nuclear plant is responsible for the temperature of that waterway, they cannot discharge as much warm water into that waterway.
2. Solar doesn’t work at night, and sufficiently scalable energy storage technology doesn’t yet exist.
3. Solar loses considerable capacity as ambient temperature increases. At 40°C ambient, you’re talking about a 15% or higher reduction in efficiency. Which would be HIGHER than the ~12% reduction in nuclear capacity Europe hmis seeing

Guys, guys, it’s not an OR, it’s an AND.

We need both nuclear AND renewables.

Oh of course, I’m not arguing against solar. Just arguing against dumb takes.

How about neither?

Well, joking a bit, but also serious. Nuclear has often been presented as working reliably regardless of circumstances, but that’s clearly not entirely true, because they require water. That is an inherent issue with nuclear, and one that isn’t always accounted for. This isn’t the first time I’ve heard about a nuclear reactor having to shut down because cooling water wasn’t available for some reason.

In the past, people have often taken the availability of water for granted, but that’s clearly not something we can afford anymore. See also the issues with water being needed to cool data centers. Combine that with rising temperatures and drought.

Not really news. France has these problems every summer since decades. It’s a common problem of river-cooled power plants. The obvious solution is to build them at the coast - like in Fukushima.