Iron fuel shows its mettle
spectrum.ieee.org
spectrum.ieee.org
My gut feeling is that transmission lines would still be cheaper. That being said long-term storage seems to be the value proposition here.
In my corner of the world coal is still frequently used to heat homes during winter. A single house uses around 4-6 tonnes of the stuff each season. This heap of coal takes a significant amount of space.
If my back of the napkin calculations are correct, the energy equivalent in iron dust would be half the volume. Of course there's the issue of weight - about 5x that of coal, but perhaps the cost of moving all that iron could be somewhat mitigated by having a rust reprocessing plant in the neighbourhood.
You will also need a very specialized furnace, and supplies of CH4.
My Uber today was a Corolla hybrid and at one point I heard the telltale clunk of the LPG system engaging. Apparently you can have that on a hybrid as well.
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 move than compared to a transmission line, but it's _stored_ energy and can be redeemed at a later time.
Is that still true? Aren't there a number of very successful grid battery installations now? And given the steady decline in battery costs, it ought to just get better and better.
List of pumped-storage hydroelectric power stations https://en.wikipedia.org/wiki/List_of_pumped-storage_hydroel...
List of (non-hydro) energy storage power plants https://en.wikipedia.org/wiki/List_of_energy_storage_power_p...
Largest battery plants in particular: https://en.wikipedia.org/wiki/Battery_storage_power_station#...
"Really small capacity" here apparently means "roughly 4 hours of discharging as fast as possible".
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 outstripping supply.
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...
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.
You could build nuclear to supply your winter power, but then you're overbuilt for summer and don't need any renewable. Or you could store heat directly in the ground like that Alberta pilot project, heat collectors on the roofs all summer drive the heat underground, pump it back out all winter.
Or our current plan, pretend to be "green" by spending money on solar while increasing coal usage and no feasible plan to replace space heating.
If we had reasonably priced seasonal storage we'd use it, but we don't need it.
Europe all gets winter at the same time. If you've got a cold snap for three weeks with low wind, the only plan is reliance on massive fossil fuel backup. The cost of keeping that capacity for only using a week a year isn't priced into solar either.
The CO2-intensity of electricity generation in France stood at around 57 CO2/kWh in 2020 (source: Statista). In Germany, the electricity mix at the same time had a CO2-intensity of 366g CO2/kWh, which was more than six times higher
But yeah Germany's approach is really working!
Depends on the latitude and these numbers seem to be for very high ones close to the polar circles.
> Not cost effective.
Are we pricing in the societal collapse due to climate change? I’d suspect a 4x overbuild would be quite cheap against that.
OTOH, keeping some natgas capacity for when a freakish cold snap with no wind hits seems kind of OK.
No, those values are far from polar circle. I'm guessing closer to central Europe, since for example in Finland the PV produces 0% during the winter months.
10-15% would be insane to get here, but there simply isn't any energy in the sun (and closer to the polar circle you get - there's no sun at all during winter) and the panels are often covered in snow in any case. And I'm not even talking about cloudy days now, but "sunny" ones.
March/October are already approaching those 10-15% levels. Nov-Feb is closer to 0% in most of the Finland.
Keeping gas power plants around for backup power isn’t all that expensive since fuel accounts for two thirds of their cost of generation.
Offshore wind is far more expensive than onshore wind and solar but even so costs about a third of new nuclear power, with strike prices in the UK of £37/MWh vs £106/MWh for Hinckley Point C. Maybe keeping gas backup adds another £15/MWh to that but it still works out at half the cost of nuclear.
By building more France will probably get nuclear costs down some, but even so will struggle to be competitive with renewables and backup.
> But yeah Germany's approach is really working!
Germany’s approach of keeping coal plants around while closing existing nuclear is extremely dumb.
Sadly, no. Given how long the CO2 stays in the air, anything less than 99.9% over all emissions from all nations — and that also includes cement and iron chemistry leading directly to CO2, cattle biochemistry leading directly to methane, etc. — then we're not pushing hard enough.
Natural gas is great as a way to buy time, but we can't let it be more than a rounding error in the ultimate ensemble… well, not unless there's corresponding CO2 capture.
Not sure how to reconcile "they aren't available" with "starting to see them everywhere".
They're great batteries (especially compared to lead acid) and at least in small quantities, they have been widely available for years.
This is specifically what I'm talking about. Because of some weird patent agreements, manufacturing of LFPs have been confined to China and they've not really been producing a large enough number of them to fill the role of grid storage (at least outside of china). [1]
[1] https://table.media/china/en/opinion/lfp-advantage-for-china...
Current worldwide lithium production is at 3% of what it needs to be to electrify every car, which is a use case that has strict weight requirements. Ramping up lithium production by a factor of 30 is a big deal, and that's before we use any of it for grid storage!
Grid batteries are static so weight is not a concern, using the chemistry whose main advantage is weight for this purpose is a waste of resources. Heavy battery chemistries have largely been ignored because traditionally batteries have always been for mobile purposes, so we can expect an even better learning curve from low energy density but cheap battery technologies such as iron-air.
There are probably other places where it's difficult to get that large-enough region, for geographic or geopolitical reasons.
In fact, you have to use some sort of transmission lines to get energy to those locations, otherwise you have no way to get energy to or from them. Even if they have local power generation, you still have to use transmission lines to get that power out.
That’s stocking btw that it takes 4 tons of coal per year per house. That’s an absurd amount.
"About 65 % of America's aluminum is currently recycled." That's pretty good. Much better than most materials.
Article says energy density of 11.3 kWh/litre.
WolframAlpha says using that for all global electricity for a day is 33e9 kg iron: http://www.wolframalpha.com/input/?i=2%20TW%20%2A%201%20day%...
Some estimates I did a while back and then wrote up nicely with ChatGPT said a global power grid would use about x100 that much iron: https://github.com/BenWheatley/Studies-of-AI/blob/main/Globa...
So the cut off between them is that if you use this for more than about four (/eight) months, the grid was cheaper.
That said, while I personally love the idea of a global grid, geopolitics rather than technical merit is likely to be the dominant constraint for any solution, as everything[0] is cheap enough that cost doesn't matter.
Also, possibly still useful for shipping? Possibly? I assume they'd prefer synthetic oil, but I don't claim any real knowledge, that's just my uninformed guess.
[0] Well, almost everything — concrete-based gravity batteries produce too much CO2 so they're expensive with current production methods just in a non-monetary sense, and antimatter production is so inefficient it's not viable, but those are the only two exceptions I know about.
It's not actually clear if transmission lines are cheaper. Ships and trains can carry a lot of mass. For an energy dense fuel, this can be cheaper. Then again, this idea needs you to carry things in both directions, both the iron and the iron oxide. That may doom this idea to being too expensive.
I can’t recall it all now, but my understanding was that if you take the entire chain from production to storage to consumption of hydrogen, it’s pretty much an unworkable engineering problem. “The closest thing to a vacuum, other than a vacuum” was one memorable quote. Happy to be shown to be wrong.
Your understanding is the result of years of FUD against it. People really need to understand that they have been lied to repeatedly on this subject. If you have a basic grasp of engineering, you should understanding that it is literally made by running electricity through water. It is an incredible simple idea that you can even do at home. And since hydrogen is already being used in a vast number of industrial and chemical processes, it should be clear that there could not be any fundamental technical challenges that haven’t been solved.
You’re argument seems to be based around economically feasibility, not technical issues, right? So then you will also agree that if green hydrogen radically dropped in cost, then you will agree that it will become a viable solution? Furthermore there will be subsidies going on, that will accelerate the process.
In fact, the problem might be that a combination of subsidies and cost reductions will drive the price to below $0/kg, causing market confusion:
https://www.spglobal.com/commodityinsights/en/market-insight...
That would be an interesting outcome and it will be interest to see how it ends up. But nevertheless, super-cheap green hydrogen should quickly refute the major arguments used against it. It is a process that mirrors what happened to wind and solar energy. They too have years of FUD followed by many skeptics who denied the possibility of cheap renewable energy. But that skepticism simply fell apart because basic economics overrule outdated opinions.
Economic feasibility due to engineering problems. Just because something can be done in a lab does not mean it can be done at scale. As an example, Musk with his stupid hyper-loop. Sure it is technically possible to evacuate a tube and send a vehicle through it at high speeds. It will never be economically feasible, however. Sometimes the engineers just have to say “not going to work” to an otherwise cool idea.
It’s not the cost of hydrogen production. It’s the engineering problems that pervade the rest of the handling, storage and distribution of hydrogen that look to be insurmountable.
The question then becomes, who's actually saying this? It's certainly not real engineers. In fact, real engineers have pointed out that it is much cheaper to distribute hydrogen than electricity:
>BRINK: How do you move the hydrogen from the solar farms?
> AD VAN WIJK: By pipeline. That’s the interesting thing: It is about 10 times cheaper to transport energy by a hydrogen pipeline than by an electric cable. That makes it possible to transport electricity very cheaply from somewhere like North Africa to the demand centers in Europe, for example.
https://www.brinknews.com/could-hydrogen-replace-the-need-fo...
And all of this is happening under the auspices of effectively free hydrogen due to a combination of subsidies and cost reduction. This should really raise the question of how any of the alternative ideas are going to compete with this, not how whether this idea can work.
I struggle to understand why you would say this. Here is one example. Paul Martin is a Chemical Engineer (that’s the right kind of engineering to talk about this topic). https://www.resilience.org/stories/2023-03-31/paul-martin-hy...
If you actually take off the “hopium” goggles and critically evaluate the problems, I think the truth is the hydrogen solution is not only unsolved it also probably can’t be solved.
This is false, as fuel cells are electrochemical systems that do not follow Carnot's theorem. Which is to say that it is fully possible to build a fuel cell that greatly exceeds the efficiency of diesel engines.
Not to mention that most of his claims are from some years ago, and are becoming obsolete even if they were true. He has not commented on (AFAIK) about the effects of subsidies nor admitted that costs are dropping rapidly. He just sounds like another anti-renewable skeptic similar to those that criticized wind and solar.
It's worth mentioning that all of them are similar in a way: Old, retired or nearly retired, and usually coming from in the fossil fuel industry. And yes, Martin is from the fossil fuel industry, and has no experience with hydrogen beyond its existence as a feedstock for oil refining. He has never had any experience with modern hydrogen-related facilities, equipment and concepts.
Engineers that actually do have experiences with those area do not agree with Paul Martin. So there are alternative viewpoints from knowledgeable people. You can look at recent statements by BMW and Bosch, including what their engineers have said. They are clearly believers of the idea:
https://www.repairerdrivennews.com/2022/09/01/bmw-bosch-anno...
I just picked a critical engineer at random, but I can see I’m wasting my time here. You are clearly not any kind of expert. I am clearly not any kind of expert. This is just devolving into nothingness, and I’ll leave it here.
You are not picking a critical engineer at random. You picking basically one of the very few credible critics, and they're all basically known to the community. The rest of the engineering community in this sector are certainly not as skeptical. In fact, you completely ignored my link about engineers that are doing real work in this area.
I asked previous about "who's actually saying this?" to the question of engineers that doubt hydrogen. And that question is still relevant, because outside of a tiny minority of scientists and engineers, most of whom are outdated and poorly informed, the rest are just armchair experts and random celebrities.
So the point is that you are simply wrong about your understanding of the issue. The intellectual community fully accepts the possibility of hydrogen as a widespread fuel and a way to solve climate change.
That is terribly naive and wishful thinking, I’m afraid.
For even the smallest-scale industrial applications, hydrogen is almost invariably produced on-site, near or within the manufacturing cell consuming it. Even if Linde charged nothing at all for hydrogen, electrolysis would still win: no 10kpsi (good lord) tank, no inevitable 1% loss per month of high-pressure hydrogen, no extra insurance premium.
If you’d dealt with hydrogen in industry, you might appreciate the problems with it. The static electric discharge from fingertip to ground required to ignite hydrogen is barely perceptible, and a ridiculously low atmospheric hydrogen concentration will burn with a very hot flame invisible in daylight.
The proposition of the public driving high-pressure hydrogen tanks around is brain-damaged. If you want fuel, you should make methanol from your hydrogen - for the same reasons that, if you want hydrogen, you already produce it from water or natural gas or propane.
Hydrogen has been an excellent topic for boastful press releases by car companies, corrupt nations, and fossil fuel producers murderously determined to continue the status quo indefinitely. It’s ideal for that, because there’s no danger of practicality.
On the other hand, real engineers with real experience in the area are saying the exact opposite: https://www.repairerdrivennews.com/2022/09/01/bmw-bosch-anno...
In reality, you are just repeating the claims of some random armchair expert. These days, those seem to be usually battery car fanatics. Though you still see the occasional pro-biofuel or pro-fossil fuel guy. Either way, it is coming from a totally unqualified person.
The issue is you’re going to need distilled water in order to create hydrogen particles.
A membrane-based seawater electrolyser for hydrogen generation (2022)
Here we propose a direct seawater electrolysis method for hydrogen production that radically addresses the side-reaction and corrosion problems.
A demonstration system was stably operated at a current density of 250 milliamperes per square centimetre for over 3,200 hours under practical application conditions without failure.
This strategy realizes efficient, size-flexible and scalable direct seawater electrolysis in a way similar to freshwater splitting without a notable increase in operation cost, and has high potential for practical application.
Hydrogen itself is more likely to be used to store energy in salt caverns, which is a proven technology for decades now. Aside from storage for the above use cases, it's a workable fuel for gas turbines for backup power.
This seems like the most likely outcome in my opinion.
Iron is not a good solution for moving energy because it is so heavy. Aluminium would be a much better solution.
See interesting chart of energy densities by weight and volume.
https://en.wikipedia.org/wiki/Energy_density#/media/File:Ene...
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. Iron oxide in nanoparticle size would likely be a pollutant and hazardous to human health, not something that will break down quickly and harmlessly.
The high fuel density and low explosiveness may make it a good use case in some niches, 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.
I am more concerned/confused by the fact that they use hydrogen to reduce the iron. That seems like a very convoluted process, why not use the hydrogen generate heat instead? Yes, it has much lower density, but it has advantages to make up for it, for instance the fact that you don't need to worry about evaporation, leakage, filters, all that at all.
https://en.wikipedia.org/wiki/Spin_isomers_of_hydrogen
freshly liquefied hydrogen contains a lot of stored energy in that form which will be released over time and cause quite a bit to vaporize, for long term storage you have to release that energy.
Thus people have looked at all sorts of schemes for storing hydrogen such as absorbing it in metals like palladium, metal hydrides, chemical carriers such as ammonia, methane, etc.
Sodium has higher energy density (3.5 kWh/L) than liquid hydrogen, there is no energy needed to store it and no catalyst is needed for the fuel cell because sodium is so reactive with water. The fuel cell is rather easy to construct (I know somebody, who has done it in a garage). NaOH solution is very caustic but also neutralizes well naturally without long term effects at least in comparison to crude oil that seems to be the better proposition. And of course sodium is everywhere, where NaCl - table salt is.
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).
As for the disposal of HEPA filteres loaded with air-stable inorganics, that still is pollution, only the kind of waste you store safely, and if not give people cancer, but highly localized so.
I'm also somewhat concerned about the nanoparticle's effect on living things. It is likely that it is only a question of local exposure, as in general once they get out they should still rust in some relatively short period of time, and as Earth is the aforementioned big ball of iron, a bit of rust in the environment is quite unlikely to hurt anything because if it could hurt a thing that thing would already be dead, but locally nanoparticles would be something weird and I could see breathing them could be problematic. It is also entirely possible that it is safe up to surprisingly absurd levels too (your body is familiar with iron, and while there are toxic doses of iron you're not getting to them with nanoparticle exposure any time soon), it would just be something that would need some study.
No it's not.
Inside the crust both Si and Al are more common.
There is plenty of Fe, which is all in oxide form. Mining and processing required.
Iron is abundant on Earth, including within the crust, where it's the fourth most abundant element (after Oxygen, silicon, and aluminium), roughly 5% by mass. And yes, considerably more prevalent in the core. Iron and oxygen account for roughly 32% of Earth's total mass, each, the largest proportion of any element.
<https://en.wikipedia.org/wiki/Earth_mass>
Sure, not as abundant as silicates. But nowhere near as rare as gold, platinum, and rhodium. Or even copper, silver, or lead.
<https://en.wikipedia.org/wiki/Abundance_of_elements_in_Earth...>
There's even a fair bit of it flowing though your veins and arteries right now.
And yes, the major ore deposits are old. Most are BIFs (banded iron formations), and date to 1 bya or 3.5 bya, laid down by early oceanic algae for the most part.
Sometimes it's more than fine to allow a slight exaggeration to pass without litigating it to death.
Crust iron is all oxide. Fe at 5% average. In some locations obviously more concentrated up to 90% ore. Not all sites are viable for mining, and this is very important to understand. Just because there is plenty of iron out there doesn't mean all of it is commercial grade.
This means energy input to turn iron oxide into iron, which the article claims could be used as fuel and/or long term energy storage.
-Fuel I don't believe for a second.
-Energy storage it's a maybe. It needs to commercially beat plenty of options. Which to me seems unlikely since the path still includes heat and steam engine which would incurr at a cicle loss of at least 50%. And this being conservative etc. Would mean a steam engine operated in a very narrow power band - which would mean a baselevel powerplant not a peaker powerplant. And didn't yet consider other possible losses, as for one, the Fe degradation over time. Energy cycles that count on heat and engine are wasteful. Could this waste be compensated by a much cheaper capex and/or opex relative to Li or similar batteries? That's a big Maybe.
I myself want to believe there is a solution to renewables intermittency. But on this one in particular, I'm quite bearish for the reasons above.
To that extent, it resembles other synfuel concepts. The principle difference being that iron-as-energy-storage entails reduction rather than synthesis, in the chemical sense, for hydrocarbon synfuels.
There's a lot to be said for options which provide long-term, "shelf-stable", environmentally-benign, high-volume energy storage with convenient storage, handling, and utilisation characteristics. I've looked with interest on petroleum-analogue hydrocarbon synthesis (Fisher-Tropf) and alcohol (Sabattier) processes for some years. Both have long (multi-decadal, approaching a century) of established use. Yes, the overall process is lossy (as little as 15% net energy recovery), but there are applications for which there are very few alternatives: powered heavier-than-air flight, marine transport, mobile use, off-grid primary or back-up power systems, heating, and industrial applications.
I think I'd made abundantly clear that the abundance question is pedantry.
Can this scale up? Or is this a small scale only solution?
Transportation. How much energy would a truck be able to move? How does it compare to a tank truck? Weight is absolutely relevant here.
Also, production. Consider that reducing iron is measured by millions of tons per year per plant, and right now, it's done burning it with plain old coal.
Seems very odd to me the subtitle of the news is 'carbon free fuel'. That alone is a massive bullshit indicator, but I digress.
How something that may have a 10% global energy recovery efficiency could beat a pure redox power storage solution? This question has been avoided so far.
I became aware of the prospect of synthesis from captured CO2 + hydrogen (from electrolysis) from a US Naval Research Lab study around 2015. Those papers had ... misleadingly-truncated citations, dating back only to the 1990s. It turns out that hydrocarbon synfuels were first proposed in the 1960s, by M. King Hubbert and studied at Brookhaven National Labs and M.I.T.
Google had an X Project devoted to the idea as well, though ran into insurmountable cost barriers.
Scaling seems to be a major concern, though the process does work at experimental scales, and produces usable fuel. It seems worth continued research based on the potential advantages, even if costs remain higher than fossil fuels. (The USNRL research suggested "competitive" costs, particularly for in situ military fuel generation, notably in aircraft carrier task groups which have ample supplies of nuclear energy, but need fuel for aircraft.)
Battery storage has numerous limitations: low energy density by both volume and weight, and the fact that whilst fuel burns off during flight (and accounts for 50% or more of take-off weight), batteries don't. In the case of metal-air batteries (iron and aluminium have both been proposed), as the redox reaction progresses, the battery gains mass as oxygen from the atmosphere is bonded to it. This poses problems for flight, and even ground-based transport tends not to work well with batteries at large scale.
Nanoparticles of iron oxide are already rust.
There is certainly some inorganic phenomenon that will turn it into normal, aggregated rust. It probably requires water and some time.
But those particles sound like the kind of thing that will stay for years on the atmosphere, and contaminate every living thing. And yeah, they are probably safe in some surprisingly large amount, so whatever direction it goes, we will only know after we start doing it.
Where does the Iron go??? It's not like Fission or Fusion is happening, right?!
This is a totally useless thing to say unless you have secret technology for core mining.
You need to extract the feedstocks for any energy-to-fuel system. Iron is cheap and simple to extract, compared to say carbon from the atmosphere.
The nanoparticles do not get released to the environment. Emissions from burning carbon based fuels also include pollutants that are hazardous to human health.
Which do get released into the environment in quite large quantities!
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).
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.
Are there numbers on the energy efficiency and costs of this process? This seems very strange. Batteries are above 90% round-trip efficiency now. This has to be lower.
The entry for iron in the link below is also higher than the iron energy density reported in the parent link (11/3 kWh/L).
https://onlinelibrary.wiley.com/doi/full/10.1002/ente.202000...
Of course, aluminum used in this way is the classic thermite reaction; I conjecture that the iron reaction is also.
I'm not criticizing the process, but it's not accurate to call it "fuel" like it could be the solution to replacing fossil fuels.
"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 transmission lines. Metals can solve a big problem in the renewable energy transition: long-duration energy storage.”"
Why not just skip the middleman? Use renewables?
There could be a space for it. Or maybe batteries will just always be better. Depends on the full costs of each and the use case. Burning fuel to make electricity is pretty inefficient, but burning fuel for heat compares better.
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 then run the iron reactor overnight, or on cloudy, windless days.
and then put back energy in the spent fuel to make new fuel again
then you have really a battery. That's how li-ion batteries work. The issue is the efficiency: how much of the energy you used to recharge the "battery" (iron) is going to be available when you discharge (burn) it
It is a bit of a fuzzy distinction. Batteries are typically simple chemical reactions that cause electrons to move around. But viewed from the outside a hydrogen fuel cell behaves the same; so why not call this one a battery too (especially since the process is reversible).
I think the one thing is that iron storage would be a potential long term form of storage, while all those other methods that you mentioned are really short term, designed primarily just to deal with the daily peaks and troughs of renewable production, but not as much the "it's been completely overcast for 3 weeks" problem. The only other form of storage I'm aware of that is also long term like that is pumped water storage, and that is obviously very geographically limited.
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.
What value? Where did any value originate in this process?
Misappropriated rare resources cause destroyed nature for the reason that capitalism said it was sound.
Every joule can only be spent once, but and as long as there is no moral coercion, there is a profit to be made from pillaging it from the supply.
I can imagine a solar plant, making iron in the day and burning it in the night and essentially act as a base load plant, the holy grail of renewable energy.
I was under the impression that basically all naturally found iron is in the form of iron oxide. Which means you first have to put in energy to reduce it to pure iron, to then burn it and turn it back to iron oxide. That's much closer to what a battery does, or hydrogen, than it is to coal.
I imagine it's still useful in many applications since hydrogen is a pain to store and transport.
And the article doesn't even hint at any way to do this using renewable energy. Which makes me suspect that no such process exists.
https://www.youtube.com/watch?v=NMJtieqVUc4
I hosted this. Getting permission from the Building department to have fire indoors was lotsa fun.
I learned that stainless steel burns the hard way. You can use stainless steel scrubby pads as a heat sink to vaporize DMT in a contraption called "the machine". Naively, I thought steel wool would work instead of the scrubby pad. It doesn't. The fibers are too small and it ignites--pretty much exactly the opposite of what you want in a vape.
Iron/steel production is one of the largest individual sources of co2 emissions and uses a lot of energy.
And then to just burn it back into iron ore for energy - At best you'll only get back the energy you expended to refine it in the first place.
Assuming they are burning scrap, it would surely be better to melt it down and recycle it as steel.
As energy storage, it may well have more energy per liter than gasoline, but it weighs many times more. There are surely better options - even in the same category, eg aluminium?
Fortunately, iron oxide can be reduced using hydrogen. In the article, they conclude that the system cost of shipping iron and iron oxide back and forth from an electrolysis facility (presumably from renewables) is lower than using hydrogen directly as a fuel.
It has the energy density of coal, only unlike coal it requires both mines as well as smelters/processing facilities to produce the iron powder. So this can only work if we build out twice the infrastructure that coal currently enjoys, with all the costs and emissions therein.
I'm so tired of breathless scientific reporting of "breakthroughs" that ignores any and all economic context. Or, like this article, treats it as a side issue to be addressed with literally one sentence.
What this does, then, is provide you an alternative storage medium that is relatively inert until you want to use it. And it provides you a simple self-sustatining scalable chemical reaction that can be started by supplying some initial heat and then goes on to produce even more heat steadily and continuously until you run out of fuel.
Solar, Wind, more/better batteries and nuclear are our best paths forward if we want to take the immediate action we need to take. If crap like this gets traction we'll just have a greenwashed future where all the coal and natural gas plants will be gone, but global emissions will still be high and power will be many times more expensive. Maybe then people will start to do math.
Back when I was in college the Environmental Science majors were a joke because the chemistry classes they took senior year were the same classes the Chemical Engineers took freshman year. I thought my university just had a crappy environmental science program, but after reading a number of articles like this one I'm thinking it might be a more pervasive issue.
I was taught that, in part, by a fed-up engineering professor.
I would hope Environmental Scientists, who are purportedly concerned with things like ocean acidity, pollution, atmospheric makeup, etc would have the chemical knowledge necessary to understand what they're looking at. Apparently whoever designed their curriculum at my almamater thought it was unnecessary.
Arguably we always are doing that, by definition. Investment is spending money on current non-optimal returns in exchange for much greater returns later.
If an investment had guaranteed success; if it had no flaws, then it would already have been made. There is nothing flawless in this world - not you or me, not Facebook or Messi, not oil or iron or renewables or nuclear.
But this fact causes large scale confusion on all sides. For those invested in the existing system, this is a threat. But for those who think it will be some other kind of green technology, this means admitting they were betting on the wrong horse the whole time.
Like in an energy plant. That during the day when there Is surpluses they generate iron powder from ironoxide and cheap electricity. And when there is no surplus they burn the iron powder to irononoxid. And they can both be stored at unlimited scale on a heap.
So in other words, this is a really crappy version of something that already exists. I guess there are three takeaways to be had:
1) We still need large scale energy storage and it simply cannot just be a pile of batteries. It really needs to be a chemical system and it really has to be able to burn.
2) But that always takes you down one road: Hydrogen or something made from hydrogen. That's the only class of chemicals that really works and doesn't involve carbon. This causes a lot of conflict since it is definitely not many people's favored energy storage idea. And since so much FUD has been flung around for so long because of that, many people have become convinced that this inevitability is actually impossible.
3) So you usually end up with two alternative ideas: Something crazy like burning metals. I've heard of burning boron too BTW. This particular proposal is a continuation of that way of thinking. Probably they are all DOA ideas. And the other is something akin to linking all of the grids across world together with vast numbers of HVDC lines. But this too is crazy, especially once you realize the sheer cost and complexity of it all. Not to mention you are still wasting oodles of energy since you have minimal energy storage.
So eventually we end up in this cycle of one crazy idea being proposed after another, and nothing of importance actually being achieved.
Why don't you try to do a Fermi estimate before voicing your concerns? Maybe things are not so bad.
Steel is one of the few materials that humans produce in quantities exceeding one gigaton per year (the other ones are coal, oil, natural gas, concrete, and 4 agricultural crops, sugar cane, corn, rice and wheat).
A lot of steel is recycled. It depends how you count, but between 60% and 90% of steel is recycled. Still, a lot of steel is produced out of iron ore each year.
Currently to make a ton of steel out of ore we emit about 2.2 tons of CO2, including upstream emissions[1, page 26]. If we make it from scrap steel, we only emit about 0.4 tons of CO2. It is projected that by 2050, both emissions will go to 0.1 tons CO2-equivalent per ton of steel.
The article mentions an energy density of 11.3 kWh per liter. Iron has a density of about 7.9 kg/l so, we're talking about 1.4 kWh per kilogram. From the article, we learn that the way the energy will be extracted from the iron powder is via burning in a regular thermal power plant. Good power plants now have efficiency of up to 64%, but let's says with the new fuel, they'll just produce 50%. The charging part will probably be more efficient, but let's say the round trip will be only 20% efficient. So what? This could still turn out to be much more economically efficient than hydrogen, or any other alternatives. If you want, we can do some estimates there too, but your concern was about emissions, not about profitability.
Let's focus on emissions. Each time you burn one ton of iron powder, you generate (assuming 50% efficiency) about 0.7 MWh of electricity. In the US, on average, in order to produce that much electricity, you emit about 0.5 tons of CO2-equivalent, according to the EPA. If you charge and burn one ton of iron only 5 times, you come out ahead. But you will charge and burn it hundreds if not thousands of times. It's just iron, it's not a battery that degrades over time. It's iron powder, after each round trip, it's iron powder again.
Each ton of iron powder can potentially reduce emissions by thousands of tons of CO2 equivalent. Each year all of humanity emits about 50 gigatons of CO2 equivalent, gross. The planet absorbs about half of that. A fraction of a gigaton of iron powder could help us get rid of all of our emissions.
This thing here could be a revolution. Until now, I thought that our only economic way to store long time or transport long distance electricity is hydrogen. Iron powder solves so many problems with hydrogen.
Feel free to criticize it, but don't simply be dismissive. Bring information to the table, so everyone here can appreciate it was worth their time reading your comment.
[1] https://rmi.org/wp-content/uploads/2022/09/steel_emissions_r...
[2] https://www.epa.gov/energy/greenhouse-gases-equivalencies-ca...
He's saying liquid hydrogen, but I gotta wonder if the the real story here is an attempt to deal with moving the energy in natural gas, since the liquified natural gas story is so shitty (expensive facilities, etc.) and pipelines are politically and logistically difficult.
I would not be surprised to see this turned into a "burn/process natural gas (in North America etc) to produce the iron 'fuel'. Ship the iron by train or boat & skip building pipelines and tankers and LNG facilities." Which gets us no further on the climate change front, but answers certain current European (esp German) ... political / economic ... problems.
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 seems to be rife with this.
Who could have guessed that snake oil could work in something as serious as the energy sector, I'm really surprised it's getting so low.
I'm going to be brutally honest, but you even hear people from first world countries playing the poverty card when you tell them they should stop driving alone in a 1 ton vehicle, and it seems sobriety and de-growth will have to convince those people that fossil fuels are a privilege, not a right.
I can bet that we are going to see people sabotaging cars, gas stations and refineries pretty soon if nothing is done. Greta Thunberg will be 25 soon and a whole generation will not tolerate more lies.
This one creates a very inconvenient fuel: iron powder. It can't be efficiently piped, and it needs some very strange technology to make it burn in controlled conditions. And you cannot use it for gas turbines or piston-based engines.
At this point, if you have hydrogen, you can just use it to produce methane that has none of these problems. Or maybe ammonia if we ever get catalysts working at mild conditions.
If we fail to, billions will die on hothouse Earth regardless.
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.
That would quite hilarious and horrific at the same time
[1] https://www.weforum.org/agenda/2021/07/clean-energy-green-hy...
This feels like a poor stop-gap that will turn into a long term solution one day instead of focussing on nuclear fusion/fission, solar, wind, beaming energy from space, etc.
I had to lookup a German word for this: Weltschmerz.
> Weltschmerz literally means 'world pain' and refers to a sense of world-weariness.
https://swzmaritime.nl/news/2020/02/27/why-iron-could-be-a-s...
> "A disadvantage of iron as a fuel for ships is the relatively high specific mass of iron powder and the increase in the weight of the iron oxide that is produced during combustion. As a result, a ship will lie deeper and deeper during the voyage."
They seem to have a prototype in the works c. 2030.
first off.... WTF? Transporting iron is cheaper than transmission lines? I call BS.
There are other ways of course, but this is only for storage and recycling uses a lot of energy.
See any textbook on the Bessemer process or iron decarburization
Lithium (Li): 3,860,000 joules/kg Aluminum (Al): 31,500,000 joules/kg Copper (Cu): 13,100,000 joules/kg Iron (Fe): 20,000,000 joules/kg Nickel (Ni): 9,800,000 joules/kg Titanium (Ti): 10,500,000 joules/kg Zinc (Zn): 3,700,000 joules/kg Lead (Pb): 2,040,000 joules/kg Silver (Ag): 10,490,000 joules/kg Gold (Au): 9,700,000 joules/kg
It has the highest density per joules/kg.
The project mentioned here is setting the iron powder on fire and need to use a steam turbine to get electric power out of it. So different tech.
https://formenergy.com/technology/battery-technology/
But yes, I was triggered with iron alone, but they both seem to burn iron. There is a whole industry of flow batteries emerging also.
Is there a known process to do this? At the moment most iron production is using coal.
Edit: Also, what about nitrogen oxides? Almost any combustion with air produces them to some degree and they are harmful pollutants. The article never mentions them.
It’s just a ridiculously expensive metal to make.
Look up how much alumina is minded all over the world, how it’s shipped to Iceland for processing because of their cheap geothermal electricity, then shipped to China to processing, then shipped back around the world to final destination. It’s crazy.
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.
Yes, it's an environmental concern for other reasons, but focusing on greenhouse considerations is fairly reasonable.
I think it's easiest to think of iron as another energy storage medium that could ease the peaks of renewable energy, by taking excess renewable energy to generate the iron, and oxidizing the iron for energy generation during peak demand periods with low renewable generation
It's like hydrogen in that way.
For some applications, mass is a critical concern (e.g., powered aircraft). For others, it's volume, say, powerplant + fuel stores aboard a marine vessel.
As I'm understanding this proposal, the iron is largely recycled, so transport of iron is relatively minimised. The concern is how much iron is required on site, and what the plant-sizing characteristics are given that.
Though of course, in any public communication of novel research and technological proposals, there's a significant amount of PR, spin, and narrative-spinning, so it's fair to be skeptical.
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 which is quite heavy?
Lastly, iron is heavy. Moving reduced iron could be expensive and dangerous.
Still, if sufficiently close to the renewable source this could provide much needed load leveling for intermittent sources.
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.
I'm going to come out and say those competing technologies are vastly more plausible and viable.
How about per gram?
> 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, but if you want to do that just do that.
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!
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.
EDIT
Missed this: "This can later be reduced—that is, the oxygen can be stripped away—back into iron powder. “You can think of iron fuel as a clean, recyclable coal,” says Bergthorson."
So guess it's all good.
Iron is just everywhere. I can go out in my back yard and find rocks which contain ore.
Imagine loading an iron rod into your car, driving for a while, and then when you get into the gas station you dump a pile of rust off and buy a fresh iron bar.
* Kids playing with iron filings sounds a lot safer than kids playing with gasoline. "Don't leave your magnets in the fuel tank; it clogs up the lines!"
* The gasoline party scene in Zoolander would need to be reconsidered.
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.