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Iron fuel shows its mettle

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Re: Iron fuel shows its mettle

#151

Post by wolverine876 »

VadimPR wrote: post #141
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…

We are already using the most economically viable option. The trouble is that it's not sustainable long term. The solution then will not be the most economical one.

> We are already using the most economically viable option.

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.

Re: Iron fuel shows its mettle

#152

Post by eddyzh »

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…

It is not an energy source. It is a (battery) energy storage solution that can scale. Meant to support renewables use at night/ low sun/low wind periods. And not on hourly scale like normal batteries but on year scale on plant level.

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.

Re: Iron fuel shows its mettle

#153

Post by ac29 »

cogman10 wrote: post #85
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…

> 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…

Assuming LFP means Lithium Iron Phosphate (LiFePO4)?

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.

Re: Iron fuel shows its mettle

#155

Post by _hypx »

VadimPR wrote: post #141
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…

We are already using the most economically viable option. The trouble is that it's not sustainable long term. The solution then will not be the most economical one.

The second most economically viable option is basically going to be hydrogen in some way. Either made from renewables or nuclear power, possible natural sources if they exist in quantity. That is why you hear about it so much.

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.

Re: Iron fuel shows its mettle

#156

Post by bryanlarsen »

coryrc wrote: post #148
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…

If we're using renewables, we need seasonal shifting, so cycle life doesn't matter at one cycle per year. 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 pl…

We don't need seasonal storage. The sun still shines in the winter, unless you're in the Arctic circle. We can use over building, production diversity, interconnection and short term storage instead. Or just use natgas peakers for the last 1% and call a 99% solution good enough.

If we had reasonably priced seasonal storage we'd use it, but we don't need it.

Re: Iron fuel shows its mettle

#158

Post by _hypx »

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…

Pipelines of liquid or gaseous fuels is pretty much always going to be the cheapest solution for energy transmission. This fact will inevitably lead to people investing in some kind of green chemical. If not hydrogen, then likely something made from hydrogen like ammonia or methanol.

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.

Re: Iron fuel shows its mettle

#160

Post by throwway120385 »

pankajdoharey wrote: post #139
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.

Who cares if it's energy intensive or inefficient if our other option for using the energy is to run it through a big resistor or to not produce it in the first place? This is a tool for repeatedly storing and releasing excess energy from power plants that can't control their output in response to grid conditions. Let's supposed for the sake of argument that battery banks were prohibitively expensive in some applications, and that hydroelectric storage was too damaging to the local environment. In those cases, your only option is to either dissipate any excess energy or to not produce it in the first place.

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.

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