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Iron fuel shows its mettle

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Re: Iron fuel shows its mettle

#31

Post by umvi »

obblekk wrote: post #14

> 0.3% of the Iron-oxide becomes nanoparticles which cannot be converted back into Iron. At that rate, 50% of the initial iron will be gone in 333 cycles of iron -> iron oxide -> iron. This a hard type of energy source to reason about: 1. It's not a pure fuel and acts like a battery most of the time, but it's also not renewable 2. Iron is extremely abundant on Earth, but it requires mining and processing to extract 3…

> The nanoparticles are not emitted in the atmosphere but captured in a HEPA filter.

If that's true, your point #3 is moot. And if the nano particles can be captured by a filter, maybe we could design filters specifically for iron oxide nano particles that would allow the nano particles to be extracted

> but I imagine it's actually more scalable and healthy to burn jet fuel and reproduce it from renewable powered carbon capture, where density is needed.

You're saying capture carbon from CO2 and turn it into kerosene? I tried googling around and everywhere I look it seems like this is currently way more difficult than renewable iron fuel (https://www.planet.veolia.com/en/how-produce-kerosene-co2).

Re: Iron fuel shows its mettle

#32

Post by usrusr »

csours wrote: post #8
usrusr wrote: post #5

I used to be very excited about the iron cycle when the first news about that brewery appeared. But these days I wonder how useful it really is, as an energy store? Won't it start oxidating at room temperature unless kept in inert atmosphere? And if that's a requirement, is it really that much less trouble than plain H2 or some gaseous or liquid intermediate?

Yes, and gasoline will evaporate, natural gas will disperse, etc. It's kept in a container until they burn it.

Sure, but liquids and gases are routinely handled in vessels with a maintenance interval of "never" on the inside, I'm not so sure that could be transferred to a powder. But this might be my lack of knowledge of existing processes in "powdery industries" speaking, if those are solved problems there I would not know.

Your mention of gasoline evaporating made me realize that some of the iron oxidating is probably not all that bad, just make sure that there's no ventilation continuously swapping in fresh air. I guess I'm looking forward to the next iron age!

Re: Iron fuel shows its mettle

#33

Post by thsksbd »

usrusr wrote: post #5

I used to be very excited about the iron cycle when the first news about that brewery appeared. But these days I wonder how useful it really is, as an energy store? Won't it start oxidating at room temperature unless kept in inert atmosphere? And if that's a requirement, is it really that much less trouble than plain H2 or some gaseous or liquid intermediate?

There's the kinetics of oxygen transport into a big pile of iron powder. If that's not good enough, you can always transport it in a closed container with a block of dry ice. You don't even have to seal it, just change the chemical potential of O2 in Fe.

Re: Iron fuel shows its mettle

#34

Post by intothemild »

balaga01 wrote: post #29
intothemild wrote: post #16

Earlier quoted context omitted.

Sure you could use renewables to make iron. But that thought process also extends to other methods too. You could use renewables to make other non renewable fuels. Why not just skip the middleman? Use renewables?

Well, it ties into the storage issue that we see with renewable. We still need energy when there is no wind at night. Burning iron at night and regenerating during the day could be a solution. It needs to prove that it can be competitive with the other methods (compressed air, li-ion batteries, flow batteries, molten salts, flywheels...).

Thank you.

Re: Iron fuel shows its mettle

#35

Post by dmix »

TheGeminon wrote: post #26
intothemild wrote: post #16

Earlier quoted context omitted.

Sure you could use renewables to make iron. But that thought process also extends to other methods too. You could use renewables to make other non renewable fuels. Why not just skip the middleman? Use renewables?

I think this is likely more of an energy storage project, rather than an energy production one (which seems to be the stance the article takes). At grid-level, battery tech is challenging, requiring technologies like pumped storage that require particular environments (e.g. damming a river) and can't really be transported. If this works out you could use excess solar during the day to deoxidize the rust produced, and…

How does that battery/production distinction work? How is it a battery if it is consuming/burning a fuel? More as a stable fallback or something?

Re: Iron fuel shows its mettle

#36

Post by cr__ »

kinnth wrote: post #21
c0nsumer wrote: post #12

Earlier quoted context omitted.

The article says this. It wraps up with: "If these problems can be overcome, you could use renewable electricity to produce iron, store it as long as necessary, transport it there and then burn it for power when needed, says Bergthorson. “Places that have excess energy could make iron, and others can buy it. This way, you could commodify renewable energy so it can be globally distributed without the need for transmis…

This is actually the same principle as BTC. High volume cheap electricity is used to process random numbers and the value is stored as BTC allowing it to be freely transferred once first mined. The green economics of this need some serious consideration as i'd be really aware if you can reprocess it and get a second reaction for less energy than it cost you to turn the rust back into free iron metal.

> the value is stored as BTC

What value? Where did any value originate in this process?

Re: Iron fuel shows its mettle

#38

Post by csours »

usrusr wrote: post #32
csours wrote: post #8

Earlier quoted context omitted.

Yes, and gasoline will evaporate, natural gas will disperse, etc. It's kept in a container until they burn it.

Sure, but liquids and gases are routinely handled in vessels with a maintenance interval of "never" on the inside, I'm not so sure that could be transferred to a powder. But this might be my lack of knowledge of existing processes in "powdery industries" speaking, if those are solved problems there I would not know. Your mention of gasoline evaporating made me realize that some of the iron oxidating is probably not a…

Handling iron particulate is well-established technology:

https://www.youtube.com/watch?v=PZHpeBubb_M

Note that this is about when it goes wrong, but also that it is usually due to cost-cutting measures.

Re: Iron fuel shows its mettle

#39

Post by thsksbd »

OrbitalPewPew wrote: post #19

Imagine thinking that a material stars can't use for fuel is one that makes sense as a "renewable energy source." These idiots need to go back and take undergraduate thermodynamics.

Stars cant use Fe's chemical energy because they're too hot and the entropy of not being bound to O2 is too high. (And Fe is a trace element).

No one is talking about using Fe as fuel in a nuclear reactor, or (even though the article muddles this) as a primary source of chemical energy.

Its a battery. A heavy, big battery.

Re: Iron fuel shows its mettle

#40

Post by OrbitalPewPew »

JoeAltmaier wrote: post #37
OrbitalPewPew wrote: post #19

Imagine thinking that a material stars can't use for fuel is one that makes sense as a "renewable energy source." These idiots need to go back and take undergraduate thermodynamics.

Confusing chemistry with fusion there.

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