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by close04 53 days ago
If your NPP output is lower than the base load (I think this is almost always the case) then the NPP will always feed all its constant production to the grid to satisfy the constant base load. If you have a battery and what to put it somewhere with the most impact, it should go next to the variable power supply, where it makes sense to store and supply later. That's what batteries do, store what you can't use now to supply it when you can't produce.

Look at this picture [0] of the German grid. Same for France [1]. Why would you store any of the nuclear output when all of it is guaranteed to be absorbed by the grid real time, day or night? You can, but it doesn't make economic sense. Batteries shine where they can smoothen peaks, like solar and wind.

The big reason to put batteries next to NPPs is the existing grid infrastructure. You can't supply GW-level power from just anywhere. It's like building a large warehouse next to a major transportation route.

[0] https://en.wikipedia.org/wiki/Base_load#/media/File:Renewabl...

[1] https://www.rte-france.com/en/data-publications/eco2mix/powe...

1 comments

There are lots of times and places where renewable production is higher than demand. When that's the case "the NPP will always feed all its constant production to the grid to satisfy the constant base load." increases costs.
> increases costs

“Increases costs” for who, the producer, the consumer, the distributor? If you have data on that I’d love to read about it.

I think the article mentions that recently batteries are always together with renewables. The reason this battery was built there has nothing to do with the NPP but with the proximity to the already developed power distribution infrastructure. You can assume they’ve all done the math when choosing to not build batteries next to working NPPs.

> You can assume they’ve all done the math when choosing to not build batteries next to working NPPs.

What a strange assumption. Batteries have become financially viable within the last ~2 years. Nuclear power plants were mostly built in the 70s and 80s.

So you focused on this but still no details on the baseless and handwavey “makes it more expensive” statement? Fine so now that batteries are affordable have you seen any deployments next to active NPPs, which today are used practically exclusively as base load and don’t need to follow demand peaks due to the ton of renewables+batteries taking that role? Did you look at that data from the French grid and how NPP production fits neatly in the base load with almost no variation? When all the NPP’s output goes to the grid no matter the time because that’s the definition of base load, what’s left to go into batteries?

Those times when renewable production is higher than the demand, the producer of renewables pays to feed it into the grid, not the NPP. That’s why they pay for the battery to store that excess, not the NPP.

Years ago when mostly unvarying power plants (coal, NPP) had to cover peaks too with help from hydro it made sense to have some form of storage. Today these plants don’t ever need to cover peaks. Their output is flat as a pancake almost and fits perfectly the role for base load. Peaks get covered from varying sources which can then really benefit from using batteries because first, they have variable production and second, they would pay for any excess power fed into the grid. Batteries help turn to profit what otherwise would be an expense. This is not the case for NPPs.

how much would costs increase? German nuclear was cheapest firm power in merit order