Probably the cheapest and best option is to build more wind and not care too much if it increases curtailment.
Yes, all the things mentioned should be looked into and done when it makes financial sense but "wasting wind" is much less a thing to worry about than "burning gas", and I'd rather waste wind than waste money.
https://www.oecd-nea.org/upload/docs/application/pdf/2021-12...
... most of the modern light water nuclear reactors are capable (by design)
to operate in a load following mode, i.e. to change their power level once
or twice per day in the range of 100% to 50% (or even lower) of the rated
power, with a ramp rate of up to 5% (or even more) of rated power per minute.
One trouble is that changing the power output does put stress on components because of thermal expansion and contraction, potentially shortening their lifespan, but it something that can be designed for.But operating a nuclear plant in this fashion pushes up the price per MWh considerably given their very high cap-ex and op-ex. And while fuel cost is negligible for nuclear, creating more nuclear waste per useful MWh generated is a further drag on costs.
So as a solution, it "works" if the nuclear plant does not have to compete in terms of price with other sources of electricity. But nuclear fails to compete on cost even if operated continuously - it's uncompetitive with cheap, quick to deploy, low op-ex, modern tech like CC gas turbines or renewables in most western electricity markets and can only survive with government subsidy[2].
[1] https://www.nrc.gov/docs/ML0703/ML070380209.pdf [2] https://www.washingtonpost.com/business/2022/04/19/biden-adm...
The big problem is that energy prices are set based on the most expensive unit that needs to be turned on to meet demand. Renewables do not tend to be that during periods of low supply, as low supply of energy in the eu market generally means sub-optimal weather conditions for renewables. It is going to be either fossil fuels, nuclear, or battery. If we take out fossil fuels then that leaves battery or nuclear. Neither is very economical without subsidies. Governments (and tax paying citizens) are however very keen on grid stability and thus willing to spend a lot of money to keep it running.
That is not a problem, it is the incentive to have supplies available so they can be turned on.
I therefore wonder if the market couldn't be structured in a better way which would still ensure that the fossil backup generators are adequately compensated but smoothes the extra cost over the remaining cheap GWh. Something like a meditating party which is aware of the production costs and buys up the daily power and sells it on at an averaged price. There are probably good reasons why this wouldn't work, but I am too stupid to figure them out.
It's worth noting there are some demand response initiatives and the like that are approaching this from the other side - they will pay a user to not use power at particular times of high load. If you don't want to pay a premium on power, I suspect there will be providers happy to oblige, so long as you are willing to forgo the 100% service guarantee.
At this point there isn't really any part of the energy grid that governments do not subsidize. They subsidize companies that provide grid stability. They subsidize renewables that provide capacity. They subsidize the customer who buy energy. They subsidize the grid infrastructure that transports the energy. They subsidize the interconnection between countries that enables trade between countries. They subsidize the cleaning up and associated costs from pollution.