zlacker

>>RobinL+(OP)
Curtailment, like negative prices, seems like something that it is hard for people to have constructive conversations about.

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.

>>ZeroGr+k8
Balancing a nationwide power grid is very complex. Some energy sources can be started and stopped instantly, but are limited - water. Others are plentiful, but unpredictable - wind. Others are predictable, but take a long time to start and stop - gas, coal(several hours), nuclear(1 day to start, fast to stop, but very expensive). A balanced grid will need all of them, will need them in quantities which can cover faults in the big producers(a nuclear reactor makes 700-800 MW). They will need them built in the right place, because while more power cables can be built, you can't transfer a lot of power on very long distances, for cost and grid stability reasons.

>>redlea+ud
Nuclear power plants can vary their output faster than most people think, see

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.

>>PaulHo+pn
Varying output from a nuclear plant is mostly achieved by simply releasing the generated steam into the atmosphere instead of sending it through the turbine[1].

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...

>>derriz+HJ
I am skeptical that renewables are cheaper than nuclear when one factors in the impossible amounts of energy storage required to make them meet the same reliability guarantees that nuclear (and fossil) can meet - indeed, as far as I know, there exists no proven, cheap, scalable technology to store power at grid scale at all.

>>dTal+ea1
>as far as I know, there exists no proven, cheap, scalable technology to store power at grid scale at all

It's called pumped storage.

We dont need as much storage as people think. Solar and wind anti correlate and a vast amount of demand can be time shifted.

>>pydry+DQ1
I was wondering if someone was going mention that. Pumped hydro is great, but it's not scalable. You need favorable geography to make it economical at all, and in the end it doesn't store enough energy to do more than smooth over transient grid fluctuations lasting a few hours. The UK is, relatively speaking, quite well provisioned with pumped hydro - its largest storage facility is Dinorwig in North Wales, which is built into a mountain with very favorable geometry - it has nearly 6 times as much capacity as the next biggest station. It can store enough energy to run the entire UK for... about 16 minutes. That's not going to do the trick if the grid runs entirely off wind and solar and you have a dark, calm day, let alone the weeks at a time that weather can be unfavorable. And there isn't anywhere to put another hundred Dinorwigs, never mind the budget.

It's because of this that there's a lot of talk about wild ideas like pressurizing abandoned mines and so on - there are a lot of mines around. But then we're back to the "proven technology" sticking point.

>>dTal+CV1
The suitable geography is considerably less rare than the nuclear and carbon industries jointly like to pretend. This has been confirmed by multiple studies (I have posted them at least 3 times before because this talking point is sadly rather common).

Nowhere is currently "well" provisioned for pumped hydro given a solar and wind grid coz while they existed for over a hundred years they have never had to store that much energy. Newer, larger ones are being built around the world. Australia will be well provisioned soon.

Go back in time 10 years when solar and wind first became economic and people made similar comments about how little of it there was (1% of total power!), ignoring the unit economics completely. We are at that exact same inflexion point with pumped hydro.

>>pydry+qW1
The largest pumped hydro facility in the world is Fengning in China, at 40GWh, and the second largest is Bath County in Virginia, at 24 GWh. Dinorwig's 9GWh is really not too shabby. Even Fengning would only power the UK for just over an hour. This is simply not the same order of magnitude for the storage you'd need to make it through a gray UK winter on renewable energy alone.

What's the longest period without wind and sun you're willing to provision for before you give up and tell the population they'll have to do without electricity for a bit? A day, a week, a month? Numerically, how much storage would that actually need? How many stations, how big? You'd need over a hundred Fengnings to power the UK for a week. Where would they go? I'm all for renewables + storage but you can't handwave these questions as FUD, it's a serious problem.

I suspect that if we committed to categorically eliminating fossil fuels, including peaker plants, the first time the lights went out because the weather was bad you'd have people clamoring to build nuclear power plants. Statistically, it'll happen at some point no matter how much storage you provision.