Here in Switzerland during some heatwaves they have to shut down nuclear plants too because the river water is too warm and adding warm water to it would kill the fish.
number6 37 minutes ago [-]
And it's not cold enough to cool the reactor
masklinn 27 minutes ago [-]
The reactor absolutely is not going to care, it’s the tertiary cooling circuit cooling for the steam turbines, it will have cooked off everything downstream long before it’s an issue.
This is entirely an ecological and safety concern.
seszett 27 minutes ago [-]
No that's never the problem, even 40°C intake is cool enough to cool a reactor, it's all just a question of returned water temperature that can be harmful to a river if too high (generally the limit in Europe is set to 30°C).
pepperoni_pizza 1 hours ago [-]
You can totally retrofit existing nuclear power plants for closed loop cooling. I'm not sure what the cost would be, though, but it might be worth doing.
Elfener 41 minutes ago [-]
I've read that in the case of Paks a retrofit doesn't make sense because the entire thing is so old and needs to be rebuilt anyway.
However, hopefully, they change the plans for (stalled project) Paks 2, because that would've used the same cooling system as the first one.
moffkalast 59 minutes ago [-]
Is it economically viable to run though? Natural draft towers or direct body of water cooling is used almost universally since it doesn't take any extra power. A large chunk of the powerplant's output would be running heat pump compressors to stop itself from exploding.
wongarsu 39 minutes ago [-]
Fully closed loop is probably not viable. But I suspect that's not the extreme GP might have meant.
If for the sake or discussion we simplify cooling to four options:
1: just passing river water through a heat exchanger for cooling
2: ingesting river water, using it for cooling, then passing it through a cooling tower before returning it to the river
3: pass the water output from the cooling tower directly back in the cooling loop, only ingest enough water to replace evaporation
4: fully closed loop via direct heat exchange with air
Then 4 is not very viable. But a lot of nuclear plants are stuck at 1 or 2, and each step up the ladder would allow them to operate in worse conditions. This one seems to be at version one
noduerme 26 minutes ago [-]
How do these things, whose sole purpose is to turn heat into electricity, end up with so much extra heat that it takes more energy than they produce to disperse it? Can't the excess heat in a closed loop system be captured and used to power the cooling? Sorry, maybe this is a stupid question.
Tade0 14 minutes ago [-]
The heat is spread out to a much larger volume.
Heat engines are most efficient when the temperature difference between the hot and cold side is high, so you need to keep it that way to extract energy.
A nuclear power plant achieves this by converting extreme heat from a small, but very angry rock to a huge lake of slightly warmer water.
There exist reactor designs which operate at higher temperatures, thus increasing efficiency, but they're complicated as everything needs to be more heat-resistant.
emsign 44 minutes ago [-]
First of all you can't retrofit every npp with that, it's a lie. And eve; if you could, you are correct, it's financially not viable. Renewable energy is always the cheaper option by far.
Luc 26 minutes ago [-]
Of course a 1960's design isn't adapted to current weather conditions. That doesn't mean the whole technology is useless, like so many commenters imply.
Any new build can and will include cooling adapted to hotter conditions.
cucumber3732842 21 minutes ago [-]
>That doesn't mean the whole technology is useless, like so many commenters imply.
First day in the comments?
Everyone knows that, or could. It doesn't matter because the point is to use it to mislead people. The extra layer of indirection causes any given rebutter have to deal with that first and once that bullshit is peeled back it's still not provable that they're lying to mislead, they could just be stupid after all.
You see this on every goddamn topic.
vrganj 3 hours ago [-]
This is happening all across Europe right now - Romania, France too.
We keep having folks here argue that nuclear, not renewables are the path to take to get rid of fossil fuels. I have strong doubts - it feels like that doesn't account for the sad realities of climate change.
cinntaile 2 hours ago [-]
People arguing for one alternative over the other are usually politically motivated. I feel like you are doing the same. Sometimes nuclear is a good fit, sometimes renewables is a good fit, sometimes fossil fuels are a good fit. Most of the time a mix is the best fit. It depends on what you are optimizing for and what is geographically, (geo)politically and economically possible. All these systems are then built using assumptions, sometimes those assumptions no longer make sense after a certain period of time and sometimes you just temporarily or permanently have to adapt to the changes in the environment. This is an unusual but expected scenario for the nuclear plants along the Danube.
seszett 24 minutes ago [-]
> sometimes fossil fuels are a good fit
There is simply NO safe level of fossil fuel use.
ben_w 19 minutes ago [-]
Disagree, it's just that the safe level is around 0.1% of current use (though I don't just mean use of fossil fuels for electricity, I mean *everything*).
dudefeliciano 19 minutes ago [-]
The point they are making is that climate change will further push these conditions, so are we willing to build more nuclear power plants, knowing that by the time they are ready to go online this problem will be worse? Or better to invest in renewables which can be implemented today and will alleviate this problem? A mix of both with heavy majority of renewables and nuclear/fossil only to guarantee baseloads seems like the best idea to me.
paganel 1 hours ago [-]
Everyone is politically motivated on this subject, and that's a good thing, because this is a political decision by default, where the "political" is comprised of is, the voting citizens. We can't let decisions like these be taken by unelected technocrats alone.
cucumber3732842 17 minutes ago [-]
>and that's a good thing, because this is a political decision by default,
Why is it a good thing that everyone and their brother seeks to apply state violence to micromanage what should be a fairly arcane technical issue?
>We can't let decisions like these be taken by unelected technocrats alone.
Do you feel the same way about topics where your opinion differs substantially from the local majority?
gib444 27 minutes ago [-]
I'm not filled with joy about my chav ("redneck") neighbours weighing in on nuclear vs solar and climate change and national and international energy markets and power distribution...
I don't have a clue either. Don't ask for my vote on how to power a country. Take my taxes and use them to listen to experts
29 minutes ago [-]
stavros 1 hours ago [-]
Agreed, whenever I hear someone say "we need more/less nuclear and less/more solar/wind", I hear "let's burn more fossil fuels while we uselessly split hairs".
vrganj 2 hours ago [-]
I'm not really opposed to nuclear power politically. I just think it's a non-starter given the much higher cost, complexity of buildout and lack of reliability.
deepsummer 57 minutes ago [-]
In countries with dark winters and without enough hydro power, the only reliable alternative are fossil fuels...
comrade1234 54 minutes ago [-]
Iceland has no nuclear power plants.
defrost 45 minutes ago [-]
Iceland is a small area, small population outlier literally sitting on two plates rubbing up against each other and a relative excess of active volcanism and large lava fields.
About 85 percent of the total primary energy supply in Iceland is derived from domestically produced renewable energy sources. Use of abundant hydroelectric and geothermal power has made Iceland the world's largest electricity producer per capita.
What works for Iceland works in few other places to the same degree (New Zealand, Yellowstone, places with thin crust and feisty caldera's).
number6 34 minutes ago [-]
Germany also has potential for 85% geothermal energy.
There are some interesting spots here but it's generally enough through the country to do it everywhere.
Munich gets quite a lot of it's energy from geothermal sources
deepsummer 49 minutes ago [-]
Countries like UK, Ireland, Germany, Danmark, Netherland, Poland also have dark winters. Solar in winter is only about a fifth of production in summer months.
Iceland has geothermal, which is amazing, but won't help central Europe.
ben_w 11 minutes ago [-]
Those places also have a huge wind resource in the form of the North Sea, for Ireland whatever the other bits of that submerged continental shelf are called, and for Poland the Baltic: https://globalwindatlas.info/en/
This is important because wind season anti-correlates with PV season.
Storage of energy in the dimensions required for weeks with almost no wind is an unsolved problem. Right now, we can't store enough to make it through a single night without using fossil fuels. Most countries don't even have the capacity to store the energy for a single hour.
RandomLensman 28 minutes ago [-]
As we can store fossil fuels for weeks of demand, we can store the required energy in chemical form, no? Germany has huge natural gas storage, for ezample.
emsign 33 minutes ago [-]
Geothermal and storage is worth investing in, investing in nuclear is not. NPPs are simply too expensive and you won't find investors unless you heavily subsidize it with tax money. Only compnies willing to invest in NPPs are those with virtually free money: the handful of AI big tech giants.
ThePowerOfFuet 41 minutes ago [-]
>sometimes fossil fuels are a good fit.
Oh come on.
eecc 44 minutes ago [-]
It’s the second of third year in a row that this happens.
It can be, but you need water, just like for solar you need sunlight and storage and for wind power you need, well, wind. Coal and gas rely on natural resources, which can be disrupted through geopolitical tension, like Russia's gas supplies into Europe getting cut off / sanctioned.
Every power source has their tradeoffs, and I don't think anyone is denying that.
What I do think is that people are making up arguments or statements that Other People have and call them out on it.
flr03 55 minutes ago [-]
Different reasons though, France has nothing to do with water level or availability. It's for environment protection.
emsign 39 minutes ago [-]
Not true at all. It's both in France and increasingly because the rivers run dry in the summer. Besides killing rivers for electricity and for "saving CO2" is as stupid as burning coal to keep HVACs running becauae the summers are getting hotter and hotter each year.
stefan_ 55 minutes ago [-]
This is a technical problem with technical solutions. You can just fix things, you don't need to throw out 30% of your power generation to pay billions for climate change vagueposting.
Cthulhu_ 39 minutes ago [-]
Kind of? I'm sure you can change a nuclear power plant so it doesn't rely on river or sea water but that's not something that can be done overnight.
Restoring river water levels can't be done through technical solutions though, they rely on the weather and we can't control that. The European river levels are largely influenced by inland rain, snowfall, and glacier forming/melting; snowfall and rain has been meagre this year, glaciers have been melting and receding for decades now.
emsign 37 minutes ago [-]
Electricity costs by nuclear power is heavily subsidized by tax money in France, so the French are paying the higher costs anyway. Just saying. Maybe there's a technical solution involving nuclear but it's really expensive compared to the much cheaper technical solution: renewable energy.
raverbashing 35 minutes ago [-]
If only there was a power source that would excel during sunny and warm days, huh
Then we could stop the nuclear plants when needed for cooling and maintenance
seszett 25 minutes ago [-]
> we could stop the nuclear plants when needed for cooling
Well that's exactly what they did thanks to solar power provided by the rest of the grid, so your snark seems rather unwarranted.
Ethan312 3 hours ago [-]
[flagged]
emsign 46 minutes ago [-]
This is what nuclear power enthusists like to ignore when they talk about nuclear power being a solution to energy and climate change.
bsza 25 minutes ago [-]
Worth mentioning we also had to shut down the largest block in our largest gas power plant on the exact same day due to an unrelated error.
Is that a fact or are you just trying to spark a debate?
mertbio 35 minutes ago [-]
They also constantly criticise Germany and its nuclear power plant closures, linking almost every negative news story about the country to this issue. It seems they’re completely unaware of the potential consequences of operating a nuclear power plant.
fylo 36 minutes ago [-]
Every power source has trade offs, bud. They call solar renewable, but in fact panels have a shelf life, and take valuable finite resources and energy to manufacture. This is what climate change activists like to ignore /s
inigyou 1 hours ago [-]
How can this be? They told me nuclear power was reliable base load.
Rendered at 10:30:01 GMT+0000 (Coordinated Universal Time) with Vercel.
This is entirely an ecological and safety concern.
However, hopefully, they change the plans for (stalled project) Paks 2, because that would've used the same cooling system as the first one.
If for the sake or discussion we simplify cooling to four options:
1: just passing river water through a heat exchanger for cooling
2: ingesting river water, using it for cooling, then passing it through a cooling tower before returning it to the river
3: pass the water output from the cooling tower directly back in the cooling loop, only ingest enough water to replace evaporation
4: fully closed loop via direct heat exchange with air
Then 4 is not very viable. But a lot of nuclear plants are stuck at 1 or 2, and each step up the ladder would allow them to operate in worse conditions. This one seems to be at version one
Heat engines are most efficient when the temperature difference between the hot and cold side is high, so you need to keep it that way to extract energy.
A nuclear power plant achieves this by converting extreme heat from a small, but very angry rock to a huge lake of slightly warmer water.
There exist reactor designs which operate at higher temperatures, thus increasing efficiency, but they're complicated as everything needs to be more heat-resistant.
Any new build can and will include cooling adapted to hotter conditions.
First day in the comments?
Everyone knows that, or could. It doesn't matter because the point is to use it to mislead people. The extra layer of indirection causes any given rebutter have to deal with that first and once that bullshit is peeled back it's still not provable that they're lying to mislead, they could just be stupid after all.
You see this on every goddamn topic.
https://www.euronews.com/business/2026/07/13/france-shuts-do...
https://www.reuters.com/business/energy/hungarys-paks-nuclea...
We keep having folks here argue that nuclear, not renewables are the path to take to get rid of fossil fuels. I have strong doubts - it feels like that doesn't account for the sad realities of climate change.
There is simply NO safe level of fossil fuel use.
Why is it a good thing that everyone and their brother seeks to apply state violence to micromanage what should be a fairly arcane technical issue?
>We can't let decisions like these be taken by unelected technocrats alone.
Do you feel the same way about topics where your opinion differs substantially from the local majority?
I don't have a clue either. Don't ask for my vote on how to power a country. Take my taxes and use them to listen to experts
What works for Iceland works in few other places to the same degree (New Zealand, Yellowstone, places with thin crust and feisty caldera's).
There are some interesting spots here but it's generally enough through the country to do it everywhere.
Munich gets quite a lot of it's energy from geothermal sources
Iceland has geothermal, which is amazing, but won't help central Europe.
This is important because wind season anti-correlates with PV season.
Plus, it's not like north-south power lines are beyond the wit of mankind. The US western interconnection includes both Canada and Mexico: https://en.wikipedia.org/wiki/File:NERC-map-en.svg
Oh come on.
At some point it will be the new normal.
Every power source has their tradeoffs, and I don't think anyone is denying that.
What I do think is that people are making up arguments or statements that Other People have and call them out on it.
Restoring river water levels can't be done through technical solutions though, they rely on the weather and we can't control that. The European river levels are largely influenced by inland rain, snowfall, and glacier forming/melting; snowfall and rain has been meagre this year, glaciers have been melting and receding for decades now.
Then we could stop the nuclear plants when needed for cooling and maintenance
Well that's exactly what they did thanks to solar power provided by the rest of the grid, so your snark seems rather unwarranted.
https://www.dert.hu/hu/sajtoszoba/0/141 (in Hungarian, couldn't find an English source)