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Iron fuel shows its mettle

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Re: Iron fuel shows its mettle

#171
post #168

Earlier quoted context omitted.

Well even engineers can have seriously incorrect understanding of an issue, especially if it is many years out of date. 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…

> You’re argument seems to be based around economically feasibility, not technical issues, right? 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 , ho…

> Economic feasibility due to engineering problems.

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.

Re: Iron fuel shows its mettle

#172

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.

Not really economically viable unless you narrowly focus on profits. For total direct and external costs (i.e. total societal costs) it's already nonviable.

Re: Iron fuel shows its mettle

#173
post #126

Earlier quoted context omitted.

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.

While that is probably true, the problem still exists that renewables produce a lot of electricity when there is not enough demand for it. Iron combustion is a solution for that problem.

Re: Iron fuel shows its mettle

#174
post #171

Earlier quoted context omitted.

> You’re argument seems to be based around economically feasibility, not technical issues, right? 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 , ho…

> Economic feasibility due to engineering problems. 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 h…

> 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:

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.

Re: Iron fuel shows its mettle

#175
post #171

Earlier quoted context omitted.

> Economic feasibility due to engineering problems. 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 h…

> 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: 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-m…

Paul Martin is not a valid authority on this. He is a known anti-hydrogen skeptic and had made many nonsensical claims about hydrogen. The most notable is perhaps his limited understanding of how fuel cells work, and his claim that fuel cells can never dramatically exceed the efficiency of diesel engines.

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...

Re: Iron fuel shows its mettle

#176

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…

You are completely off.

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...

Re: Iron fuel shows its mettle

#177
post #175

Earlier quoted context omitted.

> 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: 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-m…

Paul Martin is not a valid authority on this. He is a known anti-hydrogen skeptic and had made many nonsensical claims about hydrogen. The most notable is perhaps his limited understanding of how fuel cells work, and his claim that fuel cells can never dramatically exceed the efficiency of diesel engines. This is false, as fuel cells are electrochemical systems that do not follow Carnot's theorem. Which is to say tha…

Your argument is now “older people are stupid?”. The information is old and irrelevant? The article I linked was from this year.

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.

Re: Iron fuel shows its mettle

#178
post #175

Earlier quoted context omitted.

Paul Martin is not a valid authority on this. He is a known anti-hydrogen skeptic and had made many nonsensical claims about hydrogen. The most notable is perhaps his limited understanding of how fuel cells work, and his claim that fuel cells can never dramatically exceed the efficiency of diesel engines. This is false, as fuel cells are electrochemical systems that do not follow Carnot's theorem. Which is to say tha…

Your argument is now “older people are stupid?”. The information is old and irrelevant? The article I linked was from this year. 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.

[deleted]

Re: Iron fuel shows its mettle

#179
post #175

Earlier quoted context omitted.

Paul Martin is not a valid authority on this. He is a known anti-hydrogen skeptic and had made many nonsensical claims about hydrogen. The most notable is perhaps his limited understanding of how fuel cells work, and his claim that fuel cells can never dramatically exceed the efficiency of diesel engines. This is false, as fuel cells are electrochemical systems that do not follow Carnot's theorem. Which is to say tha…

Your argument is now “older people are stupid?”. The information is old and irrelevant? The article I linked was from this year. 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 clearly misrepresenting my point. Your authority is not really an authority for a bunch of reasons. One of which is how he is basically a retired petroleum engineer with very little understanding of the modern state of hydrogen. And yes, this usually implies an old person, something Arthur C. Clarke noticed in one of his writings about elderly scientists. And while your link is from this year, he's been saying the same thing for many years now without change. In fact, the only recent change in tone is his exacerbation, as billions of dollars are being invested anyways and he is upset about that.

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.

Re: Iron fuel shows its mettle

#180
post #148

Earlier quoted context omitted.

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.

In winter cloudy conditions solar PV produces 10-15% power. Assuming some hydro storage, that's 4x overbuild. Not cost effective.

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!

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