When people start talking about battery technology that has not even reached scale as any kind of political solution, you know people have lost the plot.
Taking one look at just the cost required for the network, even outside of the cost of any generation at all, you realize this is an insane and slapping a few solar panels down is far from a solution.
And also lets not ignore that places that have done a lot of the 'lets just build renewable and hope for the best' have very high energy prices. And maybe possible maybe sodium batteries might show up will not solve these issues.
I calculated the costs of covering the needs of Germany for a 2 days low production event (as it happened between 6-9 december) and you would need about a trillion dollar.
That's for something that cannot even garantee you more than 48h of runtime for half the country's needs.
You would need at least 4 times that to be safe.
Even if batteries price are divided by 2 (very unlikely, there are large fixed costs) you would need trillions of dollar for a single country.
That's just not happening any time soon and even in 30 years time, I doubt it will be that prevalent of a solution.
I did a conservative calculation if you started around 2000 in Germany and went full nuclear like France did. Not using any fancy new nuclear or anything. Literally just mass production of standard nuclear plants. Plus all the updates of the grid, including domestic fuel enrichment and 'waste' storage. Plus all the investment necessary to great a fully modern grid to electrify the economy.
We are talking in the order of 500 billion Euro and this is very conservative assumption on nuclear construction cost. Much worse cost then what France actually achieved in their build-out. Also much of that is actually the grid, grids are really expensive it turns out. But building nuclear in central location next to places where there used to be coal plants, makes grid cost much cheaper because most of the grid is already there perfectly positioned to feed the population clusters. And that accounts for actually increasing overall production of energy, not decreasing as Germany is actually doing.
On the other-hand for the renewable path that Germany is going since 2000, just the grid alone is going to cost more then 500 billion euro, some estimation suggest that 2000-2045 total gird investment requirement is above significantly above that. Sadly today where everything is in this different private organization, this information is all over the place and 'semi'-private organization doing different parts of the infrastructure.
In total, between all the renewables, the grid and the storage, we are talking 1.5 trillion euro and that still includes gas peakers. If you want to go beyond and really go all in, it would be even more then that, as you suggest.
Turns out, if you plan includes trying to gather solar energy in Greece and Spain (or even Egypt), transporting it to Germany and then storing it into batteries there, well yeah, that's going to be expensive. And the solar panels you import from China aren't the expensive part.
France did the exact right think in the 70/80s build reliable long term energy generation, sadly since the 90s the newer generation of French politicians done literally anything they can to handle the situation as a badly and as incompetently as possible but that's a different story.
One thing that is really important to understand is that power is not something that is uniformely needed everywhere at the same level.
Traditionally, power plants were created close to where industries needed them. Renewables require specific conditions to be viable and those factors are not necesseraly what allows industries to thrive, so you need a lot of additional infrastructure to make it possible.
Turns out this infrastructure is extremely coslty and very hard to make reliable. So, even if you have infinite money, that's a massive challenge in itself. But now Europe does not have that much money, the massive debt burdens being a large evidence of this. Yet we are asked to pay more for this future, in the name of climate change, even though most of the factors contributing to this is already happening overseas, largely out of the control of European regulations. So what is the point exactly ?
In the long run, it just ends up making everyone more dependent on external powers while weakening the position of the countries that believe in that "solution".
Nuclear constructions costs are largely overblown, because of the massive bureaucracy/over-regulation, thanks to Germany in no small part. If China can manage to build twice as fast at half the cost, we are doing something wrong for sure.
But the conversation is dominated by ideologues, that have an sadist like fetish. As if weakening your position will ever make your competition/enemies take pity on you and allows you to dictate the terms of the converstion, because people are supposed to be nice, right ?
Even with perfect implementation, there is no way to make renewables work to allow industries to thrive, and now we are going to pay the price of those poor political choices.
With all the money in the world, it was already a discutable choice, but now it is just replacing depence on fossil fuel with depence on overseas manufacturing (most of it in China). Funny thing is that China is not that stupid, and we are selling them the knowledge/skillset to become dominant on the cheap.
I just can't fathom what was going on in the mind of the decision makers 20 years ago, but now it seems they are just insane. There is no way it will work in 15 years, yet we needed that power generation yesterday.
In the process of trying to make climate change better, we have done the reverse. Now people are burning more wood, and I feel like we might go back to coal if electricity doesn't become cheaper (for residential heat). Gas is hopeless, even if the depency on Russia wasn't that strong.
Electric cars are very nice but if it turns out to be more expensive to run them than just using foreign oil it's not going to happen.
I'm just rambling at this point but it feels like there was a large anti-nuclear sentiment by people who are dominated by irrational fears and they have dominated our politics for the worse. It's really not usefull to fear a nuclear meltdown if you end up making your people poorer overtime. Why would you fear something with such a low probability of problems if you end up having to become dependent on foreing power that has no such quaslm.
France had the right path but then leftist ideologues took power and Germany's sabotaging did the rest. In theory we are not at war but in practice, there is very much an economical/ideological battleground going on and we are losing it.
Taking one look at just the cost required for the network, even outside of the cost of any generation at all, you realize this is an insane and slapping a few solar panels down is far from a solution.
And also lets not ignore that places that have done a lot of the 'lets just build renewable and hope for the best' have very high energy prices. And maybe possible maybe sodium batteries might show up will not solve these issues.