4 ms·
Looks pretty interesting. Note this is a coupling technology, i.e. the power input is at the reduction stage when iron oxide is reduced back to metallic iron vi
by photochemsyn 5y ago
Looks pretty interesting. Note this is a coupling technology, i.e. the power input is at the reduction stage when iron oxide is reduced back to metallic iron via the use of hydrogen (generating water). To make it a non-fossil process, you have to scale up hydrogen-from-water using wind/solar:
> "The resulting iron oxide is a solid material, so it can be captured after the combustion process. It is then reused by regenerating it with green hydrogen into flammable iron fuel. In this way, iron fuel offers a revolutionary method to store energy in a circular and carbon-free fashion."
It has some real advantages over shipping hydrogen, as hydrogen is tricky to work with, relative to methane. There is an alternative process, developing direct-air-capture of atmospheric CO2 and using the hydrogen to reduce the CO2 to CH4, which has the advantage of being able to use existing natural gas pipelines for transport and distribution. In contrast this iron process has some long-term storage advantages; it could serve as a way to store excess wind/solar power over longer periods i.e. months. The notion it could be used to fuel long-distance shipping is also intriguing: ships could use hydrogen to regenerate their iron fuel at the end of each voyage.
However this all depends on massive scale-up of hydrogen-from-water. That hydrogen can be used in many industrial processes, including also fossil-fuel-free steel production. Without that, this iron process can't be run at any scale.
- galangalalgol 5y agoIs there a way to make an iron oxygen battery, maybe a thermal single use one? Direct to electricity is so much more efficient than combustion. I don't want to trade oil wars for lithium wars, iron wars seem less likely, so that is a plus.
- dragontamer 5y agoOf course. Iron has an anode voltage of 0.2V though. A far-cry from Li-ion's more useful 3.7V. EDIT: My search-engine abilities apparently failed me. I'm seeing 0.44V as the voltage... well... whatever Iron's voltage is... it is pretty small. That's my point. There's a reason we didn't make Iron batteries. Iron definitely stores electrons, but the voltage dropoff leaves a lot to be desired...
- mrfusion 5y agoYou could wire them up in serial to increase the voltage.
- jfengel 5y agoCan you really add nineteen .2V sources together to get one 3.8V source? I know that the basic high-school version of E&M says that serial voltages add, but does that work in real life? Or is that the frictionless-massless-pulley of electricity?
- jacquesm 5y agoThe voltage isn't really relevant.
- dragontamer 5y agoVoltage * Electrons == energy. Iron stores 2 electrons at very low voltage. That fundamentally limits its energy density. Li-ion stores ... some number... of electrons at 3.7V. Looking at the periodic table, I think 1 electron? In any case, the big 3.7V drop really changes its energy / power characteristics. You'll need additional cells to increase either voltage or current (doesn't matter which: electric-engineers can convert either voltage or current into power). But without fundamentally good voltage or current (ie: stored electron) stats, you're just not going to have much energy storage. And if each of those cells are heavier because you're using say... a heavier element (ex: Iron) instead of lighter elements (ex: Hydrogen or Li-ion), then its that much worse.
- jacquesm 5y agoThey're not aiming to use this for a mobile application.
- dragontamer 5y agoI'm sure they aren't. But the status-quo for chemical energy storage (that is burned / re-released) is maybe Hydrogen? If you don't care about weight / density issues, then a giant steel-tank containing many/many tons of Hydrogen Syn-gas might be a better storage option than iron? Hard to say really. I'm willing to see people experiment with the technology. Iron is one of the most abundant elements after-all, so any use of Iron will almost certainly have raw cost-benefits. But will it be cheaper to use the iron as energy storage? Or is it cheaper to turn the iron into steel, and then pump Hydrogen into the Steel like a balloon and pressurize-store Hydrogen at 10,000PSI or whatever?
- photochemsyn 5y agoBattery technology development is a huge field with a long record of failed promises (often related to issues like lifetime, flammability, manufacturing cost, etc.). One interesting recent development is the replacement of the cobalt needed in lithium batteries with iron. Cobalt wars in Africa's Congo are a current issue: https://nextmoneyng.com/2021/12/22/the-cobalt-war-the-sino-american-battle-for-supremacy-in-the-democratic-republic-of-congo/ https://nextmoneyng.com/2021/12/22/the-cobalt-war-the-sino-a... Now it seems that cobalt can be replaced with iron with no efficieny/storage capacity losses: https://crm.org/articles/a-clean-industry-revolution-the-lithium-iron-oxide-battery https://crm.org/articles/a-clean-industry-revolution-the-lit... Lithium itself doesn't really seem replaceable for where it's used, in applications that demand relatively high energy density and voltage.
- otherotherchris 5y agoThe world has a nearly infinite supply of lithium. Evaporating naturally occurring brine in poverty stricken shitholes is just a lazier way of extracting the tiny amount that we've used historically rather than capital intensive extraction from spodumene, clay, and geothermal or desalination wastewater.
- yellowapple 5y ago> Evaporating naturally occurring brine in poverty stricken shitholes Come to think of it, I guess Nevada is a poverty stricken shithole, but it's my poverty stricken shithole and I'm proud of it.
- bdamm 5y agoConveniently, lithium is also abundant and can be mined from many different sources, including the ocean. So wars over lithium seem unlikely, and lithium shortages also seem unlikely since the main constraint is over scaling up efficient mining.
- imtringued 5y agoI hope that lithium recycling is going to be more cost effective than extracting new lithium. In theory it should be a very straightforward process compared to mining.