[hn_throwaway_99]

"Seasonal storage" is a problem so far out that it feels like it's not even worth worrying about until renewables are a much higher percentage of the overall energy mix. What I mean by this is that even places that (for example) have a huge abundance of solar power during the day still have to burn fossil fuels when it's nighttime or when it's cloudy - solving the "24 hour problem" will still take a lot more renewable capacity than we currently have.

And even then, we already have the ability to create synthetic fuels from electricity, so any new development would need to be competitive with what we can already do.

[pfdietz]

I disagree! It's a vital problem to solve, especially if solar becomes significantly cheaper than wind (as appears to be happening; solar has the better experience rate). And solving it punctures one of the last arguments bad-faith nuclear advocates use to argue against renewables.

I will once again point to Austin Vernon and Standard Thermal, which has an approach that could truly solve the problem. The first principles analysis of the issue shows the problem with "sand batteries" and the like.

https://www.orcasciences.com/articles/standard-thermal

"Given that heat capacities of solids are all generally similar at ~3kb per atom, we’d need to store heat in a solid that costs ~$10-30/ton or less and tolerates very high temps. But nothing built on a foundation or made in a factory is sold for less than $100/ton. There’s almost nothing that even gets shipped in the dollar per ton range."

https://www.austinvernon.site/blog/standardthermal.html

https://www.standardthermal.com/