Comment by epistasis

6 hours ago

Doubtful, the tradeoff is solar cost versus storage cost. Pumped hydro and gravity are waaaaaaaay too expensive compared to excess solar panels. Pumped hydro takes massive construction projects, which are very very expensive these days. Gravity storage (non-water, meaning non-hydro) never made any sense at all, the material costs are just way too high.

Iron-air storage is still being proven out, but it still requires so much material that only getting 1-2 cycles per year just won't justify it, because electricity is going to be so cheap.

It's hard to overstate how cheap solar panels are these days. Even in the US, which has costs 3x-5x the rest of the world because of failed protective tariffs.

>Doubtful, the tradeoff is solar cost versus storage cost.

The arbitrage is solar cost vs storage cost vs other energy source cost vs capital cost vs transmission cost.

Appropriately priced risk with all of those factors in and what you get out is solar+storage capping the price of other energy sources.

Lithium is the way, almost as cheap as sodium for a superior capability profile. Like solar, it just got cheap enough incredibly fast.

https://pv-magazine-usa.com/2026/07/27/global-battery-storag...

https://www.spglobal.com/energy/en/news-research/latest-news...

https://ember-energy.org/latest-insights/global-electricity-...

  • Cost is influenced by demand. To put this in perspective about 60 TWh of electricity is used globally per day. About 1 TWh of lithium batteries were produced last year.

    Even if every country tried to provision just one day of storage, that would cause a massive spike in demand that would inevitably drive up prices. Not to mention it would make EVs more expensive which would have its own negative consequences for emissions reductions.

  • Cheaper yes, but I don't think Lithium is that cheap, or ever will be. I think storage (even the expensive ones like pumped hydro) will become more useful over time to handle day/night issues. Probably even enough to handle 2-4 week variations in weather. However for seasonal weather storage is going to be too expensive compared to just building a more solar panels that we don't use in summer.

    Of course once we have solar that we won't use in summer there will be programs to use that power. I suspect things like ore refining, steel mills, and the like: will start running in summer only. They will go offline in winter for maintenance. (Investors will make a ton of money buying in summer and selling in winter - as they already do for lots of other commodities that have seasonal aspects)