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Iron fuel shows its mettle

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Re: Iron fuel shows its mettle

#131

Post by SmooL »

hankman86 wrote: post #114
SmooL wrote: post #71

Earlier quoted context omitted.

> 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 m…

Yes, but transmission lines can only go so far, and you still lack the ability to arbitrage over time instead of just spatially. E.g. from a solar power POV, it's night everywhere in a given region at the same time.

Re: Iron fuel shows its mettle

#132

Post by Animats »

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…

Yes. See "blue hydrogen", "grey hydrogen" (from natural gas), "black hydrogen" (from coal), "turquoise hydrogen" (from methane)...[1]

[1] https://www.weforum.org/agenda/2021/07/clean-energy-green-hy...

Re: Iron fuel shows its mettle

#133

Post by _hypx »

samus wrote: post #117
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…

> 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.

Re: Iron fuel shows its mettle

#134

Post by scottLobster »

And just like articles about hydrogen, no mention of the extraction/distribution supply chains needed or the costs/emissions involved. Nope, just focus on our fancy (ZERO EMISSION) generator and ignore how the inputs are actually produced.

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.

Re: Iron fuel shows its mettle

#135

Post by Slava_Propanei »

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…

[dead]

Re: Iron fuel shows its mettle

#136

Post by Slava_Propanei »

nyc_data_geek1 wrote: post #97
concordDance wrote: post #95

Earlier quoted context omitted.

While it's very true that greenwashing is a thing, bans on fossil fuels are not the right approach. You need sin taxes that account for the cost of the externalities instead. A CO2 tax is sensible, "degrowth" is a horrific thing that will kill billions.

Done correctly, degrowth need not lead to billions of deaths. We desperately need to restructure our economic systems and societies to account for the reality that infinite economic growth on a finite world is not possible, realistic or desirable. If we do so, we can minimize the bleeding. If we fail to, billions will die on hothouse Earth regardless.

[dead]

Re: Iron fuel shows its mettle

#137

Post by dmix »

balaga01 wrote: post #46
dmix wrote: post #35

Earlier quoted context omitted.

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?

Well, if you can burn it to produce energy + spent fuel 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

Thanks that makes sense

Re: Iron fuel shows its mettle

#138

Post by cmrdporcupine »

“it’s more efficient to produce iron from hydrogen gas than to produce liquid hydrogen. So iron powder as fuel is more expensive than gaseous hydrogen but cheaper to produce and move across the oceans than liquid hydrogen.”

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.

Re: Iron fuel shows its mettle

#139

Post by pankajdoharey »

scottLobster wrote: post #134

And just like articles about hydrogen, no mention of the extraction/distribution supply chains needed or the costs/emissions involved. Nope, just focus on our fancy (ZERO EMISSION) generator and ignore how the inputs are actually produced. 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 o…

This is another Aluminium Air battery, same concept different metal. None of them considers splitting water is energy intensive and inefficient. Another hydrogen fool cell category fuel imo.

Re: Iron fuel shows its mettle

#140

Post by gpm »

xyzzyz wrote: post #89
rootusrootus wrote: post #81

Earlier quoted context omitted.

> not good enough for grid-scale requirements 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.

There are successful grid battery installations, but as far as I know, there are no grid-scale battery installations. Existing installations have really small capacity, and are only used for things like demand smoothing. The only energy storage solution deployed at scale is pumped hydro storage.

For anyone wondering

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".

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