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Comment by cultofmetatron | Hacker News Reader

sounds like Iceland would do well to export hydrogen from electrolysis

Iceland exports renewable energy in the form of aluminum. They have the potential to develop more energy but it's controversial because of impact on the landscape.

What type of energy can they develop? Iceland is well known for their geothermal energy I wouldn’t have thought that would have a huge impact on the landscape more than any other low rise industrial buildings.

70% of electricity is hydro, most of the rest is geothermal. On the consumption side about 70% is used for aluminum.

I ran into a fascinating paper published in the 1950's by a Norwegian group who ran a pilot plant to electrowin iron from iron-sulfide waste from a copper mine. They claimed something like 4-5 kwh per kg. Unlike electrowining aluminum it's a room temp aqueous process. My thought is, it's probably economic if you have access to intermittent sources of really cheap electricity.

Aluminum is called congealed electricity due to the energy intensive manufacturing process and recycling is very economical.

Transporting hydrogen is expensive. It also has a tendency to leak.

> It also has a tendency to leak.

But I mean, that has to be a limitation of current technology, right? There has to be engineering solutions that we can devise to make it as safe statistically as for example gasoline transport?

Hydrogen has the nasty property of leaking through many materials, including metals. It also needs to be kept extremely cold. Both properties make it much harder to transport and store. It’s not clear that technology must exist that makes transporting and storing hydrogen as safe and economically viable as gasoline.

Even storage of helium has largely been solved, and that is far more tricky than hydrogen. It’s just expensive.

Helium is inert and not prone to explode when it sees the first spark. Also, as you indicate: storing helium is expensive - it is only economically viable because there is no competing product and hence whatever the price for helium storage is, it will get paid.

Remind me but there is also no way to make new helium. It’s not a renewable, is it?

I thought it was only available as a byproduct of natural gas collection.

If we ever figure out fusion, some forms of fusion result in helium.

If we ever figure out fusion, would this become a moot point or even more important than ever?

> But I mean, that has to be a limitation of current technology, right?

Not much. Hydrogen has a tendency of assuming a form that no material can hold.

People have been working on chemical storage, but the efficiency always suffer.

No, it's not just a matter of technology, or at least not in ways that are readily addressable. Hydrogen molecules are so small that the simply pass through solid matter as if it were loose-weave cloth. Worse, it embrittles most metals.

And the leaked gas, especially if in an enclosed space, is flammable or explosive over a very wide range of concentrations.

Long-term storage, transport, and use, at scale, is hugely problematic.

https://www.sciencedirect.com/topics/engineering/hydrogen-mo...

https://en.wikipedia.org/wiki/Hydrogen_embrittlement

https://www.sciencedirect.com/topics/engineering/hydrogen-ex...

If you have cheap enough energy that you're making hydrogen, can't you also make hydrocarbons? Granted, at the efficiencies we're talking, their only real use would be air travel (and petrochemicals, I suppose).

Yes. That's remarkable more sensible than futzing with naked hydrogen molecules, though the challenges here have been great as well.

I covered the topic in a series of posts based on then-new research about six years ago. That's ... not developed much further:

Primary article: https://old.reddit.com/r/dredmorbius/comments/22k71x/us_navy...

Others: https://old.reddit.com/r/dredmorbius/search?q=fischer-tropsc...

The main development since has been Foghorn, a Google (Alphabet) project attempting to develop the technology. It failed.

https://x.company/projects/foghorn/

What is the oil-cost-equivalent of existing synfuel technology?

(for uses such as air travel)

IIRC at $150 oil these synfuels were already competitive?

Varies by study, though upshot of the USNRL study wss that for net cost point-of-use (deployed carrier task force) it is competitive now (roughly $50-60/bbl cost of oil).

I'd argue that fossil fuel oil is grossly underpriced, by an order of about 10^6, but that's a longer discussion.

That seems to have the added benefit of removing CO2 from the atmosphere (many potential processes, according to wikipedia get carbon from the air).

> And the leaked gas, especially if in an enclosed space, is flammable or explosive over a very wide range of concentrations.

So just have a small fan that constantly flows air around the container to remove all the leaked gas? They do it with heat from the batteries in EVs (which if heat up too much can explode). What is such a big deal?

Safe probably yes. Economically competitive is much harder.

They might be just connected to the Euro-Powergrid in the future: https://www.landsvirkjun.com/researchdevelopment/submarineca...

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