Interesting concept, but it's basically trying to store hydrogen for winter, with up to 60% losses. It's main advantages are that it's kinda simple and shouldn't have a charge/discharge limit, but it's really just meant for cold climates where you would have a surplus of solar in the summer and you could use it much later, like in the winter. Not gonna be great for grid level storage, to lossy.
this post was submitted on 02 Sep 2024
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It seems like it's best use case would be in conjunction with nearby buildings. Where the waste heat can be used for heating.
Not solved but it is a step in the right direction. Just powder rust and hydrogen in tanks
They're using hydrogen to de-rust iron, and later let the iron rust again. I don't have a degree in chemistry, but that sounds like a scam.
There are basically two sources of hydrogen that matter at an industrial scale: fossil fuel cracking (not clean energy) and electrolysing water. In the first case, if you want power it's more green to burn the fossil fuel directly.
And if you're electrolysing water and then using the hydrogen to chemically derust iron, it would (as far as i understand with high school chemistry) be strictly more efficient to electrolyse rust directly. The oxygen can dissipate into the environment or be reintroduced as necessary, like with a sacrificial metal for ship's hulls.
It's undoubtedly innovative that they have a relatively efficient way to store the latent chemical energy of hydrogen given an excess of hydrogen, but in terms of energy storage that is putting the cart before the horse.
it would (as far as i understand with high school chemistry) be strictly more efficient to electrolyse rust directly
I'm not a chemist either, but I do know a bit of chemistry.
Typically, you need a solution of NaOH (sodium hydroxide) to directly reduce iron oxide in an electrolysis cell. If your iron oxide contains impurities, those may react with NaOH and ruin the fun. Also, if you have exposure to CO2, your NaOH will gradually degrade, producing NaHCO3 and losing potency.
My impression: wet electrolysis is great for making high purity iron, but it would be hard to make it work for energy storage.
I think on YT thunderf00t was attempting to use a mix of Sodium and potassium metals for combustion producing water and some "white clouds".
Instead of Iron or rust, you could separate Sodium out of Salt-water and start depositing and collecting sodium metal to store under oil or some non-reactive container. Then you could use that sodium metal for later reactions.
From fission I believe the lowest stable element you get after fission ends up being mostly Iron. I suspect Fusion is also very similar after He-H-He fusion reactions I think the most stable element you can reach is also Iron.
Iron is mostly not energy-dense mostly stable element that rusts Fe-II or Fe-III or Fe-V .... I think those are the non-organic iron compounds with Oxygen / hydroxide ?
So it is probably a very stupid and bad idea to use Iron as the primary energy storage since it will not have the density or the capacity to use long-term.
That is also why Li-Fe-Po batteries exist..... Lithium - Phosphate ? works better with the Iron as some kind of stabilizing agent maybe ?
But this does sound a lot like a scam and not really there yet.