Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel • Hacker News Board

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#81

Post by jojobas » Mon, Apr 03, 2023, 1:25 PM UTC

yxhuvud wrote: post #73

jojobas wrote: post #70

Earlier quoted context omitted.

So far it's easier and more efficient to reserve/contract some hydro (dam) storage than store/pool hydrogen for continuous operations.

That sounds very location dependant and not necessarily feasible at all given higher and higher share of wind power being used. That hydro will be needed during periods of low wind to stabilise everything else.

The whole point of the grid is to de-localize power.

Direct hydrogen reduction plants pretty much don't exist yet, might as well build them where electricity can be stored efficiently. Some of the biggest hydro plants were built specifically to power aluminium smelting nearby.

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#82

Post by credit_guy » Mon, Apr 03, 2023, 3:47 PM UTC

jillesvangurp wrote: post #77

rocqua wrote: post #69

Earlier quoted context omitted.

Could ammonia be used for stable seasonal storage of energy? The abstract suggests that ammonia is much nicer to transport and store than hydrogen. If we can use it to store summer solar to run winter heat-pumps with a low roundtrip efficiency but even lower costs per kWH of capacity it could really help.

It could work theoretically. The only question is if it is economical to do so. And the answer to that is probably not. It ranks pretty low on the list of possible solutions in terms of cost and efficiencies. Hydrogen and ammonia (you typically generate one to generate the other) are interesting as a fuel in some use cases (anywhere the weight of lithium ion batteries is a problem basically). Main use cases seem to b…

That's not quite correct.

Long term storage solutions are dominated by capital cost. You can use batteries to store electricity from day to night because you recoup part of your capital investment every day for ten years or so. But if you can only sell electricity once a year, then whatever profit you make it better be good, because you only get that 10 times in 10 years. The alternative is to have dirt cheap capital cost.

Pumped storage works where the lake and dam already exist, because the capital storage is essentially zero.

Everywhere else, nothing works. Batteries don't work, chemical storage (like ammonia or hydrogen) doesn't, compressed air, or molten salt, nothing works.

What will work is a way to "cheat". If you can mimic the day-night cycle of batteries and make a profit every day, you win. The way to do that is by long-distance transportation: you make ammonia in Australia, or Morocco, or Saudi Arabia and sell it in Japan, China or Europe. You may incur round trip losses of 80% or more, but if the price you pay for one kwh is one cent, and you sell for 10 cents, you can still make a profit.

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#83

Post by conradev » Mon, Apr 03, 2023, 5:36 PM UTC

shagie wrote: post #27

conradev wrote: post #9

Earlier quoted context omitted.

This is how Iceland exports the bulk of its hydroelectric energy, but they use aluminum

I was going to correct you with geothermal, but then I looked it up and it turns out that the majority of Iceland's electrical production is indeed hydro rather than geothermal (TIL). In finding the source for this, https://en.wikipedia.org/wiki/Energy_in_Iceland aluminum was the thing of note there. I was aware that this was the main power consumption (tangent to reading Artemis by Andy Weir). > ... This trend conti…

Yes! It's the similar with Norway. One of the largest exporters of oil, but entirely hydroelectric for electricity generation. It's the fjords!

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#84

Post by kragen » Mon, Apr 03, 2023, 8:19 PM UTC

cyberax wrote: post #74

rocqua wrote: post #69

Earlier quoted context omitted.

Could ammonia be used for stable seasonal storage of energy? The abstract suggests that ammonia is much nicer to transport and store than hydrogen. If we can use it to store summer solar to run winter heat-pumps with a low roundtrip efficiency but even lower costs per kWH of capacity it could really help.

Ammonia can indeed be used as a longish term energy storage. It's not as great as methane (that can be pumped into underground caverns), but it liquefies at room temperature at just around 9 atmospheres or at -33C at atmospheric pressure. Though it's pretty poisonous if it leaks.

it's caustic if it leaks, but in the environment it quickly reacts to produce nontoxic products

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#85

Post by rstuart4133 » Tue, Apr 04, 2023, 12:58 AM UTC

Schroedingersat wrote: post #32

PaulHoule wrote: post #4

Earlier quoted context omitted.

i think the question is how far you are shipping the hydrogen. If, say, people are making hydrogen in (say) the Middle East and shipping it to (say) Europe then the overhead of liquifying or compressing H2 is on the same order as converting to ammonia. In that paper they demonstrate that you can just use the ammonia directly to reduce iron and not have a separate system to convert it back. If you have a big wind powe…

>90% of the world's iron ore comes from very sunny places. Easier to just ship steel rather than iron ore and ammonia. For the last 10%, move the iron ore the other way (or still use local solar energy, because it is still cheaper than shipping ammonia).

> Easier to just ship steel rather than iron ore and ammonia.

Australia has a lot of high grade coal, which can be used for steel making (unlike low grade coal). And Australia has enormous quantities of high grade iron ore (as in you can weld to the rocks found in some parts of the country). Yet to the frustration of many Australian's we don't make steel. Instead we export the coal and ore to countries that make the steel, and they export the finished product back to us.

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#86

Post by Schroedingersat » Tue, Apr 04, 2023, 3:31 AM UTC

rstuart4133 wrote: post #85

Schroedingersat wrote: post #32

Earlier quoted context omitted.

>90% of the world's iron ore comes from very sunny places. Easier to just ship steel rather than iron ore and ammonia. For the last 10%, move the iron ore the other way (or still use local solar energy, because it is still cheaper than shipping ammonia).

> Easier to just ship steel rather than iron ore and ammonia. Australia has a lot of high grade coal, which can be used for steel making (unlike low grade coal). And Australia has enormous quantities of high grade iron ore (as in you can weld to the rocks found in some parts of the country). Yet to the frustration of many Australian's we don't make steel. Instead we export the coal and ore to countries that make the…

Easier to shift the blame for producing 10% of the world's emissions with 0.3% of the world's population that way.

Plus doing anything else might see Australia benefiting from their natural resources. Last time a government tried that, the CIA and Britain delivered a new one.