[Azsy]

You're missing a lot of background on how these markets work. And i'm not remotely qualified to explain them.

But, very broadly and simplistically speaking.

We are not even remotely close to living in a "We have too much power" world. ( Markets will change drastically then.)

All the nuclear supply has already been sold and is being constantly used 100% of the time. It never makes sense to turn off the nuclear power plant.

There is more demand then that, not meeting the demand is catastrophic.

If a popular sports is on TV and halftime everybody boils water, or the wind is unexpectedly low, or some part of the grid is having trouble.

We must still meet the demand.

Turning on a gas plant is the cheapest solution we have at the moment.

[BenoitP]

> All the nuclear supply has already been sold and is being constantly used 100% of the time.

This couldn't be further from the truth, at least for France: hover over the lower graphs to animate the source upper graph here: https://app.electricitymap.org/zone/FR

Every single day nuclear oscillates between 60% and 80%, in strong anti-correlation with wind, solar and border exchanges.

With hydro and pumped storage, this margin is well enough for attending to peak demand. And it is economically viable; This is the thing about nuclear: it costs practically the same wether you're at 20% or 95% of the plant's capacity. You consume your fuel faster, but it is only a small fraction of the cost (15% IIRC). And you still get 0 CO2 emission.

And with current gas prices this is the cheapest solution we have at the moment. (not the cheapest in terms of political will, but educating masses can solve that)

[adrianN]

If you're at 20% capacity it costs about 5x as much as when you're at 100% capacity. With nuclear almost all the cost is in building (and decommissioning) the plant.

[japanuspus]

Working in the strategy back office of a one of the worlds largest producer of renewable power, I feel I have a reasonable grasp of the problem here. Not sure what background you believe I am missing.

The point I was trying to make in my second paragraph is that when hydrolyzers get sufficiently cheap that you can buy enough to cover your peak over-production and let them idle when you are missing power, then you have effectively moved the elasticity from the production side to the demand side -- and then slow baseload does not require you to derate down your renewables.

This is far from the situation today where hydrolyzers are so expensive that you need to run them at pretty high utilization to make the economics work out.

[wazoox]

The question is: given that we MUST be reducing our CO2 output extremely quickly (5% a year, equivalent to an additional COVID19 crisis every year), what are the chances for your magical cheap hydrolyzers to 1° be developed 2° be deployed at scale before large parts of the world dive into climatic chaos?

BTW there is a very efficient way to run hydrolyzers at 95%: run them on nuclear power. Problem solved?

[johnchristopher]

> All the nuclear supply has already been sold and is being constantly used 100% of the time. It never makes sense to turn off the nuclear power plant.

Assuming the plant operations are running smoothly https://en.wikipedia.org/wiki/Nuclear_power_in_Belgium#Hydro...

Which will be less and less the case for the European nuclear champions whose plants are approaching their 40-50 years lifespan of commercial support and safe operations (or so I am told) and it's going to cost a lot to replace them, more than going full renewables apparently.

In Belgium, at some points we had to shut down offshore wind turbines because there was not enough demand on the grid and turning off and on our nuclear plants would take too much time.

Gas plants don't have that problem (or so they say). So we are building some to compensate until we have enough renewables to shut them off for good.

Also, SMR are gaining tractions so who knows.

Disclaimer: I hear both sides, one claiming we don't need nuclear to reach our emissions carbon target and the other claiming we need classic nuclear plants to manage climate change and I don't know who's right.

[yobbo]

> We are not even remotely close to living in a "We have too much power" world

Not a "world", but this happens locally in Europe due to wind/solar momentarily producing more than demand. There have been instances with negative prices.

Anecdotally, one mitigation seems to be adjusting the local base voltage to 220V so that peaks due to solar stay below 240V (or something like that).

Nuclear can, at least theoretically, be throttled hour-by-hour over the day to compensate wind, although hydro is probably more cost-effective if available.