> solar and wind anticorrelate more than you think
They anticorrelate in some locations. In others, they don't. Here in Finland in the winter you get effectively zero sun. We also get persistent stationary anticyclones. That means potentially over a month of temps in the -30°C region, and zero wind.
Australia is extremely sunny. California is even better, they are modeling that assuming they keep their current hydro capacity, they only need to add ~3h in batteries. Hot places also do better than cold places, because the usage peaks track the sun.
> In Europe or America you might need 7-8 while in carbon industry PR models (the same people who denied global warming) seem to think you need 300+.
How on earth do you expect 7-8 to be enough? 300 isn't enough either. The real number for a fully renewable-based grid here is somewhere north of 2000.
Renewables are great in some situations. There are places in the world that should go for 100% renewables as quickly as possible. It also makes sense to locate a lot of the high-consuming industry in such places. But before you hawk your solution everywhere, you need to actually study the local conditions, and not try to extrapolate anything from Australia.
I think it also depends on other stuff. Spain gets bunch of sun even when there's the deepest winter in Finland but even if they are technically part of the same grid, the challenge is getting the energy there.
Spain and Finland are not part of the same grid. Spain is in the CESA, Finland is in the NSA.
>They anticorrelate in some locations. In others, they don't. Here in Finland in the winter you get effectively zero sun.
Virtually nowhere gets zero sun.
Finland is also unusually blessed with tons and tons of hydropower potential which functions both as a battery as well as power generation.
As well as a very low population density.
It is also possibly the best advert for not using nuclear power ever given the disaster of recent projects (e.g. EDF cost overruns).
> How on earth do you expect 7-8 to be enough? 300 isn't enough either. The real number for a fully renewable-based grid here is somewhere north of 2000.
2.000 hours of storage would equate to 83 full days of electricity demand. That's on its face absurd. Most models assume that a "Dunkelflaute" (span of time with significantly reduced solar and wind output) will last at most 10 days. Add a few days as a safety margin. And that is all of Europe becalmed and dark, as the entire European electricity net is synchronized and transfer capacity between various regional grids is continuously expanded.
Power transmission is a thing. And where you can't lay down a transmission line, you can convert electricity into h2 or methane and put it on ships, just like we do with dino juice.
> Most models assume that a "Dunkelflaute" (span of time with significantly reduced solar and wind output) will last at most 10 days.
The longest recorded in Finland is 90 days. More than two weeks of it continuously happens nearly every winter.
> as the entire European electricity net is synchronized
It is not. The CESA is synchronized. The various peripheral areas are not part of it.
> Power transmission is a thing.
It is not a thing you can trust. We have only just gotten a very sharp reminder of that. We have a neighbor that likes to cut sea cables as a fun past-time activity.
> you can convert electricity into h2 or methane
I am very pro that, but this will take a very long time to build out.
> The longest recorded in Finland is 90 days.
Not trying to diss Finnland, but the country requires less than 1,000,000 Terrajoulehours of energy per year. That's like a few percent of Germany's usage. I'm sure Europe could cover you.
> It is not. The CESA is synchronized. The various peripheral areas are not part of it.
You are correct. But transmission lines do exist and synchronization would be possible. The baltic countries have done so in 2025 to get away from the Russian grid.
>> Power transmission is a thing. > It is not a thing you can trust.
You trust it now. My guess would be that most fossil fuels in Finnland are imported and that the country is already deeply dependent on cross-border electricity transmission (as basically every other country in Europe)?
For most countries, energy independence is no realistic option and never has been since serious expansion of industry. It's something you factor into hardening your infrastructure and Finnland can hedge against this with land-based transmission lines to Sweden and building out capacity for h2/methane imports.
> I am very pro that, but this will take a very long time to build out.
Longer than the presumed 20+ years to build even a single nuclear reactor?