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Iron fuel shows its mettle

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Re: Iron fuel shows its mettle

#141

Post by VadimPR »

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.

Re: Iron fuel shows its mettle

#143

Post by scottLobster »

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.

Right, but from an emissions standpoint this is a bad idea too. You not going to create an emission-free iron mine/processing supply chain any time soon. This just moves the emissions up the chain and would take decades to build out. It might be just as bad as coal in terms of emissions at the end of the day, and marginally better at best.

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.

Re: Iron fuel shows its mettle

#144

Post by Tagbert »

euroderf wrote: post #103
fnordpiglet wrote: post #74

Earlier quoted context omitted.

Iceland has absurd amounts of spare energy. So they bring in ships full of bauxite and refine it into aluminum blocks then load it back on the ship. Aluminum is refined by electrolysis, so it’s a perfect way to export their excess electricity. That’s stocking btw that it takes 4 tons of coal per year per house. That’s an absurd amount.

I'm a serious PITA about recycling aluminum. I have this mental image of vast quantities of bauxite and energy being tossed out whenever an aluminum container (or bit of foil) is not recycled. But I don't have any firm numbers.

According to: https://www.lehighcounty.org/Departments/Solid-waste-managem....

"About 65 % of America's aluminum is currently recycled." That's pretty good. Much better than most materials.

Re: Iron fuel shows its mettle

#145

Post by mrguyorama »

marcosdumay wrote: post #73
jerf wrote: post #61

Earlier quoted context omitted.

To a first approximation, Earth is a big ball of iron, so losing 50% of the iron in 333 cycles doesn't seem like that big a deal. Getting more iron is an energy issue rather than an availability issue. 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 p…

> once they get out they should still rust in some relatively short period of time 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…

Maybe then we could stop putting iron filings in children's cereal as a supplement.

Re: Iron fuel shows its mettle

#146

Post by onlyrealcuzzo »

jerf wrote: post #61
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…

To a first approximation, Earth is a big ball of iron, so losing 50% of the iron in 333 cycles doesn't seem like that big a deal. Getting more iron is an energy issue rather than an availability issue. 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 p…

> so losing 50% of the iron in 333 cycles doesn't seem like that big a deal.

Where does the Iron go??? It's not like Fission or Fusion is happening, right?!

Re: Iron fuel shows its mettle

#147

Post by mrguyorama »

samus wrote: post #126
hankman86 wrote: post #112

Or you just use the iron to build more towers for wind turbines. Or transmission lines to send renewable electricity to where it is needed.

There is no shortage of iron, while this is another way to make usage of abundant renewable energy. Especially when at the destination actually heat is required. Apart from that, neither wind turbines nor more transmission lines help with the problem of making excess energy available for future use.

Using electricity to run a heat pump will beat combustion in efficiency, and that only becomes way more true when the energy source starts as electricity being sunk into creating a synthetic fuel.

Re: Iron fuel shows its mettle

#148

Post by coryrc »

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…

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 plan, pretend to be "green" by spending money on solar while increasing coal usage and no feasible plan to replace space heating.

Re: Iron fuel shows its mettle

#150

Post by wolverine876 »

scottLobster wrote: post #143
VadimPR wrote: post #141

Earlier quoted context omitted.

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.

Right, but from an emissions standpoint this is a bad idea too. You not going to create an emission-free iron mine/processing supply chain any time soon. This just moves the emissions up the chain and would take decades to build out. It might be just as bad as coal in terms of emissions at the end of the day, and marginally better at best. Solar, Wind, more/better batteries and nuclear are our best paths forward if w…

Then the issue is with the chemical engineers, who haven't learned the waste, counterproductiveness and foolishess of dismissing other ideas, viewpoints and people. It's a vicious cycle - it greatly limits their ability to learn what they don't already believe, or deal with challenges to their ideas. The only solution is to give no validity to such dismissals.

I was taught that, in part, by a fed-up engineering professor.

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