In January 2025, Germany burned about 236 TWh of fossil fuels.
You cannot even mostly replace fossil fuels with solar.
fossil fuels are very inefficient when used in most applications (especially ICE and oil for heating). As countries use more and more electricity instead of fossil fuels to generate motion and heat, total energy demand will decrease accordingly.
Currently, Germany imports almost all of its fossil fuel from abroad. Mainly Norway, USA, Gulf countries, etc. Russia used to play an important role and we paid dearly for that. As we are for the reliance on the US, I guess.
We could actually bring our energy dependence closer to home and make it cheaper by substituting fossil fuel imports with solar + battery with the PV part being distributed across northern African countries. But most likely it will be more convenient (if less efficient) and politically desirable to create a mix of domestic and souther European sources, with specialized stuff like H2/Green NG imports from Iceland and other energy rich places being mixed in.
Also, Germany will (and does) a large share of it energy requirement not from solar, but from wind. Already, renewable energy has very much softened the effects of the Iran war on electricity prices. They never exceeded the highest levels of 2025, while fossil fuels jumped to levels last seen immediately after Russia's invasion of Ukraine and are still elevated over 2025 levels.
And if you had invested in Drake Landing https://en.wikipedia.org/wiki/Drake_Landing_Solar_Community solar setup instead of PV, then neither the Russian invasion of Ukraine nor Hormuz blockade would have been a huge deal. The cost of energy is destroying your industrial base.
> Also, Germany will (and does) a large share of it energy requirement ... from wind
15TWh in January 2025. Again, you burned about 230 TWh of fossil fuels. Nearly every heating system is over 80%, electricity closer to 50%, so lets say 150TWh. Do you have an order of magnitude more land and water you're able to put wind generation on? And are you willing to base your life and economy on not having Dunkelflaute?
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.
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.
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.