[out_of_protocol]

> hold a charge for around a hundred hours

Meaning background discharge is quite high, impacting efficiency. Good enough to smooth daily peaks though

Also, 10x cheaper than pricy li-ion might not be enough, there are lots of other [weird] solutions, like pumping water up. Better question - how many cycles will battery last? This impacts price a lot

[alwa]

Shuttling water around, though, depends on having a bucket big enough and high enough to put enough water into to matter. A big ol’ bucket of rust might be easier to site if you don’t have a dam or a hillside reservoir handy.

[giaour]

I think this was just poor wording in the article. My local power company (Dominion Energy VA) recently started a huge iron-air battery project because the technology supports 100 hours of active discharge [0]. I'm sure there's some background discharge, but it takes a lot longer than 100 hours for iron to naturally rust through.

[0]: https://www.pbs.org/wgbh/nova/article/iron-air-battery-renew...

[NullPrefix]

Pumping water up requires massives amounts of water, rarely available for regular homes