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Danube's record low levels force shutdown of Hungary's only nuclear plant

bbc.com

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Re: Danube's record low levels force shutdown of Hungary's only nuclear plant

#211

Post by leonidasrup »

pojzon wrote: post #156
ccozan wrote: post #106

Earlier quoted context omitted.

Batteries? Starting this year, in Romania you cannot put new PV capacity online without the storage for it, is mandatory. Possibly for existing ones, but I am not sure.

In Poland you cannot own big capacity storage because it makes you independent from the grid and Gov does not want that. So you can have storage, but not too much, only as much to still be dependant on the grid. See the hypocrisy here?

You are not allowed to have own PV and big capacity storage without connection to electric grid?

Re: Danube's record low levels force shutdown of Hungary's only nuclear plant

#212

Post by leonidasrup »

one33seven wrote: post #83
Luc wrote: post #43

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.

There's a nuclear reaction in the sky beaming free energy to us, let's just use that

According to solar statistics by country in 2025:

https://en.wikipedia.org/wiki/Solar_power_by_country

Hungary had the highest share of produced solar electricity of all the countries in the world 27.3%. And even with this results nuclear energy is usefull for them and plan to build new reactors. (with help from Russia, so there may be same changes in this plan)

Re: Danube's record low levels force shutdown of Hungary's only nuclear plant

#213

Post by leonidasrup »

notabotiswear wrote: post #176
JeremyNT wrote: post #119

Earlier quoted context omitted.

You can do low(er) head pumped hydro storage [0] [0] https://en.wikipedia.org/wiki/Ludington_Pumped_Storage_Power...

Can't speak for Hungary specifically, but the problem with flat terrain wrt hydro storage isn't just elevation difference - which can be offset with flowrate - it's the large surface area to storage and to depth ratios. Large lake means more losses, mainly due to evaporation, but seepage is also to be expected. Now put this fact in the thread's context: water shortage/stress...

Hungary is very flat.

"Most of the country has an elevation of less than 200 m. Although Hungary has several moderately high ranges of mountains, those reaching heights of 300 m or more cover less than 2% of the country."

https://en.wikipedia.org/wiki/Geography_of_Hungary

"Hydroelectricity is not prevalent in Hungary due to unsuitable geographical conditions and civil resentment. The country's capacity of hydroelectricity was 57 MWs in 2015."

https://en.wikipedia.org/wiki/Hydroelectricity_in_Hungary

Re: Danube's record low levels force shutdown of Hungary's only nuclear plant

#214

Post by leonidasrup »

Kon5ole wrote: post #168
pojzon wrote: post #154

Earlier quoted context omitted.

Where are the comments about „molten-salt reactors dont need any of that”. And a closed water loop. China builds them on a desert and we cannot build them anywere in Europe due to plain stupidity.

>we cannot build them anywere in Europe due to plain stupidity. Economics I think. Nuclear power has gone bankrupt in France already (arguably more than once) and gotten bailed out. Now they produce electricity at a price that's often above market price, with losses covered by the taxpayers. This despite relying on cheap cooling from rivers. Adding more expensive cooling won't help. We've quite recently reached mass…

The bad financial shape of EDF had multiple reasons:

1. Cost overruns in construction of the new EPR reactors. The EPR is a extremely safe and as a result extremely overengineered and expensive design. The aim was to merge the French N4 design and German Konvoi design and have a standard design which would satisfy nuclear regulators in all countries. France wants now to simplify EPR and build cheaper and simpler EPR2.

2. EDF was mandated to sell large part of it's electricity production at bellow the market value. The ARENH mechanism.

"The ARENH (which in French means “regulated access to historic nuclear energy”) was created in 2011 in the context of the opening of the electricity market to competition. The law that provided a framework for this opening-up had the main objective of enabling all consumers to benefit from the competitiveness of the French nuclear fleet. Before the ARENH, EDF was the main electricity supplier, covering 95% of the French territory (the rest being covered by local distribution companies). Under the ARENH, so-called alternative suppliers (i.e. other than EDF) obtained access to a regulated price (€42/MWh) for the electricity produced by EDF’s historic nuclear fleet within a volume limit of 100 TWh per year. This is equivalent to almost a third (27.64%) of 2024 French nuclear production (361.7 TWh)."

https://hayaenergy.com/blog-end-of-french-nuclear-procuremen...

Re: Danube's record low levels force shutdown of Hungary's only nuclear plant

#215

Post by leonidasrup »

masklinn wrote: post #89
voakbasda wrote: post #88

Earlier quoted context omitted.

Begs the question: coul reactors use radiative air cooling? Channel the water through a huge radiator and transfer the heat to the air

Not really, a large reactor is way too power dense. An EPR reactor has a thermal output of 4.6GW. And the tertiary is cooling steam turbines so it's below boiling, you'd need something like 10 sqkm worth of surface, per reactor, with an environment cool enough that this could actually radiate. Even using industrial air-cooling design you'd need on the order of a million sqm or two (for reference a good quality comput…

Mochovce nuclear power plant, with evaporative cooling towers, uses around 21.6 to 24.8 million m³ per year depending on operating units and seasonal weather demands. (About 0.7 m³ per second)

https://www.seas.sk/wp-content/uploads/a3/b4/2023_SE_NPP_ENG...

Re: Danube's record low levels force shutdown of Hungary's only nuclear plant

#216

Post by pojzon »

leonidasrup wrote: post #211
pojzon wrote: post #156

Earlier quoted context omitted.

In Poland you cannot own big capacity storage because it makes you independent from the grid and Gov does not want that. So you can have storage, but not too much, only as much to still be dependant on the grid. See the hypocrisy here?

You are not allowed to have own PV and big capacity storage without connection to electric grid?

You cannot have big storage either way. Its normal to have two installations and be able to switch between them.

Not in Poland, because you are too independent.

Re: Danube's record low levels force shutdown of Hungary's only nuclear plant

#217

Post by peterashford »

cozzyd wrote: post #165
peterashford wrote: post #161

Earlier quoted context omitted.

Scott base in Antarctica (NZ's scientific research base) is installing wind turbines and batteries and getting rid of diesel generators.

Yes but the South Pole burns jet fuel. Not much wind and 6 months of darkness. The hut point peninsula is consistently windy though and the turbines are pretty! https://photos.app.goo.gl/goDVb7KuiKr6soHT6

So, larger batteries, then. Or produce hydrogen from excess wind power in the summer as a chemical battery.

Re: Danube's record low levels force shutdown of Hungary's only nuclear plant

#218

Post by leonidasrup »

pojzon wrote: post #216
leonidasrup wrote: post #211

Earlier quoted context omitted.

You are not allowed to have own PV and big capacity storage without connection to electric grid?

You cannot have big storage either way. Its normal to have two installations and be able to switch between them. Not in Poland, because you are too independent.

The legislation was updated:

"According to the adopted act, devices with a capacity of up to 30 kWh are exempt from any construction procedures; only reporting to the grid operator (OSD) is mandatory. Those between 30 kWh and 300 kWh in a building and 30 kWh and 2000 kWh freestanding are obliged to prepare a land development plan and make fire safety arrangements."

https://renewablesnow.com/news/poland-adopts-rules-to-ease-e...

Re: Danube's record low levels force shutdown of Hungary's only nuclear plant

#219

Post by noduerme »

Tade0 wrote: post #52
noduerme wrote: post #42

Earlier quoted context omitted.

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.

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 increasin…

okay but to maybe beat a dead horse, if you have these enormous cooling towers spewing out steam, is the steam coming out the top of those just not economically viable to use to run smaller generators or something?

Re: Danube's record low levels force shutdown of Hungary's only nuclear plant

#220

Post by leonidasrup »

bequanna wrote: post #201
slow_typist wrote: post #129

Earlier quoted context omitted.

You still need water when cooling with towers. Instead of heating the river you consume some of its water and release it into the atmosphere.

Not TOO much loss tho, right? I thought the cooling tower design helped maximize cooling and minimize loss as steam.

You try to maximalize evaporation. Evaporating water removes heat very efficiently with relatively small amount of water loss.

Short introduction into cooling towers:

https://m.youtube.com/watch?v=tmbZVmXyOXM

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