Submission Statement

One of the challenges for the widespread adoption of green energy is the lack of large-scale, long-term energy storage. While lithium-ion batteries seem like a potential solution, they rely on scarce materials - often mined under poor working conditions. Furthermore, their short effective operating life and sensitivity to extreme hot or cold makes them only a subpar solutions for a green energy future. The introduction of low-price, sand-based batteries, which are able to store heat for months at a time, could offer a promising alternative.

I originally posted this article in /r/ConstructiveNews.

The following submission statement was provided by /u/ChriAZii:

Submission Statement

One of the challenges for the widespread adoption of green energy is the lack of large-scale, long-term energy storage. While lithium-ion batteries seem like a potential solution, they rely on scarce materials - often mined under poor working conditions. Furthermore, their short effective operating life and sensitivity to extreme hot or cold makes them only a subpar solutions for a green energy future. The introduction of low-price, sand-based batteries, which are able to store heat for months at a time, could offer a promising alternative.

I originally posted this article in /r/ConstructiveNews.

Please reply to OP's comment here: https://old.reddit.com/r/Futurology/comments/10h1z2n/climate_change_sand_battery_could_solve_green/j55x4va/

This is a good idea, if you're going to use the heat directly for home or water heating. However, it's not very applicable if you primary need is electricity.

I'd be happy to have a few cubic meters in a box in my garage ready to supply hot air when I need it. Haven't seen this suggested as an approach at all and can imagine industrial and commercial would be the most obvious target.

At a grid scale, sand batteries using resistive heating can regenerate electrical power with ~53% round trip efficiency, LCOS of maybe $0.05/kWh.

https://arpa-e.energy.gov/sites/default/files/2021-03/07%20Day1-Zhiwen%20Ma_NREL.pdf

Babcock and Wilcox are commercializing this technology now.

> The efficiency falls dramatically when the sand is used to just return power to the electricity grid.

It seems like a major drawback that the stored energy can only be used as heat.

Still, a step in the right direction. Bonus points for being based on an absurdly common and valueless material.

Heats the main use of energy in a lot of countries

>One of the big challenges now is whether the technology can be scaled up to really make a difference - and will the developers be able to use it to get electricity out as well as heat?

>The efficiency falls dramatically when the sand is used to just return power to the electricity grid.

So it's useful where you have district heating, but that's not most places.

Not really useful to turn the heat back into electricity.

It's something but it doesn't solve green energy's "big problem" like the headline suggests.