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Iron fuel shows its mettle

spectrum.ieee.org

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Re: Iron fuel shows its mettle

#111

Post by elihu »

jokoon wrote: post #91

At that rate, there should be an encyclopedia dedicated to all projects that can be described as greenwashing. I think it's a new strategy to "drown the fish", by flooding the media with "green" technologies just to pretend to say "we heard you, we are going to change the world with green new things" only to save more time until everybody realize each of those new projects are just not viable. The air travel sector s…

1 ton vehicles would actually be an improvement on the status quo, at least in the U.S. where a "small" car is usually more like 3,000 to 4,000 pounds.

Also, if self driving becomes wide-spread and successful, we're going to start seeing a lot of zero-occupant cars on the road, most likely bringing the average vehicle occupancy below 1.

Re: Iron fuel shows its mettle

#113

Post by samus »

howlin wrote: post #100

I don't really understand why iron is being considered over aluminum. Is aluminum production from ore too complex compared to iron? I would have to imagine burning metallic aluminum produces much more energy per gram.

Aluminium production is complex and might be less efficient per kilogram than iron production. Also, compared to iron there are no known processes to employ hydrogen, which can be had from green-ish sources, in aluminium production.

Re: Iron fuel shows its mettle

#114

Post by hankman86 »

SmooL wrote: post #71
Tade0 wrote: post #50

> “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 transmission lines. Metals can solve a big problem in the renewable energy transition: long-duration energy storage.” My gut feeling is that transmission lines would still be cheaper. That being said long-term storage seems to be the value prop…

> My gut feeling is that transmission lines would still be cheaper Transmission lines are great for moving electricity, but only if there's demand for that electricity _right now_. Otherwise, you have to store it - which is a problem, because battery tech right now isn't great (or rather, it's not good enough for grid-scale requirements) . This iron powder could be thought of as a "battery". It might be harder to mov…

But isn’t that the point of transmission lines - match supply and demand? Given a large enough region, there is going to be a place where renewable electricity can be produced. Case in point being offshore wind turbines where there are almost always strong winds to spin these. Moving this electricity to where it is consumed is a huge issue though. Existing power grids were created with centralised power stations in mind, which are usually located close to where the electricity will be needed.

Re: Iron fuel shows its mettle

#115

Post by cogman10 »

concordDance wrote: post #96
cogman10 wrote: post #85

Earlier quoted context omitted.

> or rather, it’s not good enough for grid-scale requirements I disagree with this point. LFP batteries are cheap, high density, and have huge cycle life. The big drawback of LFPs is manufacturing is just starting to ramp up on them. That is, they aren’t available. LFPs just came out of patent protection last year and you are already starting to see them everywhere. The biggest problem with LFPs today is demand is ou…

Got any numbers here?

For LFPs at the moment we are looking at 100->150/kwh of storage. [1]

Cycle life is around 3000->10000 cycles depending on how deep the cycles are (more shallow cycles, longer battery life). [2]

Note: Cycle life is about how long it takes for a battery to lose 20% of it’s capacity. That doesn’t mean you can’t still use it.

[1] https://www.fastmarkets.com/insights/the-ev-battery-chemistr...

[2] https://www.powertechsystems.eu/home/tech-corner/lithium-iro...

Re: Iron fuel shows its mettle

#116

Post by bbojan »

The elephant in the room are, as always, nitrous oxides (NOx).

Whenever you burn something in a nitrogen atmosphere, NOx are created. They contribute to acid rain and the formation of smog, and are a trigger for asthma.

Re: Iron fuel shows its mettle

#117

Post by samus »

rfreytag wrote: post #60

I assume they are using renewable energy to reduce naturally-occurring iron oxide. When the iron is burnt are they going to do with pure oxygen? Otherwise they'll get pollutants like nitrogen dioxide, possibly ozone. And the 0.5% not burnt will also become a pollutant unless carefully removed in some smokestack scrubber. Or is this 'burning' to occur some kind of iron fuel cell? How would they liquidize the iron whic…

The article assumes the viability of a hydrogen-driven process to reduce the iron. The intention is to establish a circular economy of reducing iron oxidized by burning it in the proposed fashion.

The byproducts from burning iron are no more noxious than burning fossil fuels, possibly less so. Filtration technologies exist as well.

Of course this technology would have to compete with other technologies to make use of excess renewable energy, like liquid hydrogen storage and transport (which it has several advantages over), iron-based battery technologies, or green-produced carbon-based fuels. I guess it makes the most sense in applications where heat instead of electricity is required.

Re: Iron fuel shows its mettle

#118

Post by samus »

thescriptkiddie wrote: post #104

> Iron oxide can also be reduced to iron using hydrogen > Altiro gets around this problem by adding a little natural gas This is transparently just green washing from the fossil fuel industry. There is no way that this will be an efficient energy storage mechanism and it definitely won't be carbon neutral. Developing cost-effective methods to produce steel from iron ore without the use of coke (coal) is important, bu…

The natural gas is used to help starting and stabilizing the flame. Actual use of natural gas is probably negligible to the total output of the process.

Re: Iron fuel shows its mettle

#119

Post by Retric »

concordDance wrote: post #96
cogman10 wrote: post #85

Earlier quoted context omitted.

> or rather, it’s not good enough for grid-scale requirements I disagree with this point. LFP batteries are cheap, high density, and have huge cycle life. The big drawback of LFPs is manufacturing is just starting to ramp up on them. That is, they aren’t available. LFPs just came out of patent protection last year and you are already starting to see them everywhere. The biggest problem with LFPs today is demand is ou…

Got any numbers here?

They’re cheap enough for EV’s, but the big number here is you can get 10,000+ charge/discharge cycles. Predictions are near term ~2c/kWh grid storage looks realistic which completely changes the economics of the electricity grid. (As in whatever you pay for the electricity to charge the batteries you need to charge 2 more cents/kWh at discharge to break even.)

Pair with renewables and not only is nuclear and coal looking obsolete but even natural gas is uneconomical at current prices. Of course the economy reacts as you start to bring this stuff online which means wholesale natural gas prices could fall quite a bit etc. You also need enough wind/solar/hydro to actually charge the batteries, but that doesn’t seem to be an issue either.

Re: Iron fuel shows its mettle

#120

Post by scythe »

volkl48 wrote: post #110
GlibMonkeyDeath wrote: post #87

Sounds like one of the least efficient energy storage ideas I've heard in a long time, I wonder how this is getting funded? Hmm, let's check to see who is behind this...the founding professor https://www.tue.nl/en/research/researchers/philip-de-goey/ is a fellow/awardee of the Combustion Institute, gets funding from ERC, etc. OK, so I guess all that European taxpayer money won't spend itself, and if you have a hammer…

> Meanwhile, stationary class (i.e. relatively poor energy density) iron air batteries are making commercial progress. https://pv-magazine-usa.com/2023/06/12/form-energy-to-deploy ... Also seems worth mentioning ESS. https://essinc.com/ They're a bit further along (scaling up from low-volume production, some installs in the wild) with a different approach to the use of iron (flow batteries).

ESS should not be mentioned except as an example of how prone the green news cycle is to fraud. As I detailed last year, their claims are highly dubious:

https://news.ycombinator.com/item?id=31430227

(previously I misspelled the last name of Sri Narayanan as "Narayan", for which I belatedly apologize)

And that prediction was substantiated when they were subject to a class-action shareholder lawsuit in February involving a fabricated customer which was actually a subsidiary:

https://www.bloomberg.com/press-releases/2023-03-10/the-law-...

The other shoe has yet to drop, but I suggest that any battery company without publications should be considered with appropriate salinity.

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