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After many false starts, hydrogen power might now bear fruit

economist.com

321–330 of 343 posts

Re: After many false starts, hydrogen power might now bear fruit

#321

Earlier quoted context omitted.

Nonsense. No one's going to use lithium ion batteries for this use case.

Right. It's one of the common anti-renewable canards that batteries would be used for more than diurnal smoothing.

Lithium ion batteries at that. There are other types like lead-acid that are cheaper, their lower energy density doesn't matter much for grid storage.

Re: After many false starts, hydrogen power might now bear fruit

#322

Earlier quoted context omitted.

> 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?

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…

> 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?

Re: After many false starts, hydrogen power might now bear fruit

#323

Earlier quoted context omitted.

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…

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).

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

Re: After many false starts, hydrogen power might now bear fruit

#324

Earlier quoted context omitted.

You're off by a factor of 10 based on wages for cleaners in Pakistan which is about $1/hr. http://www.salaryexplorer.com/salary-survey.php?loc=164&loct...

Using the average number from that source you get 356,000 PKR yearly * 30 people = ~$64,000, even using the low end from that site is only a factor of 2 off not 10. The numbers were actually based of the high end from above in the chain "for one laborer to clean panels is probably about $250-300 a month (USD equivalent, in rupees) in that area. That would be a good wage compared to construction work or farm work in t…

My apologies, I read your original statement of raw wages as being for the 10-15 days you were talking about, rather than yearly wages.

Re: After many false starts, hydrogen power might now bear fruit

#325

Earlier quoted context omitted.

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?

Re: After many false starts, hydrogen power might now bear fruit

#326
post #320
post #296

Earlier quoted context omitted.

Issue is that water has 2 hydrogens and methane has 4, so typically it is produced by using methane. It’s not really about that, we don’t lack water or methane. The issue is rather about the energy required to produce given amount of hydrogen. Electrolysis requires 2-3 as much energy as steam methane reforming already if you just look at energy of chemical reactions, and moreover, steam reforming requires just heat,…

1. Electricity is getting cheaper all the time. The cheapest forms, wind and solar, involve no detour through heat. Anything that uses electricity instead of something that produces CO2 is a big net win. 2. Huge efficiency gains are to be had, in electrolysis, via catalytic action, needing only transition from lab to production funded by sufficient demand for the hydrogen. 3. There has been great success with direct…

Yes, it is conceivable that you could use cheap electricity from renewables, but it would have to be a lot cheaper than electricity from natural gas for it to make economic sense, probably something on the order of 5-6x cheaper. You get a factor of 3x just by using natural gas to heat directly, and then you need to account for bigger capital expenses for building plant and storage, because the cheap renewables are not available round the clock, so your production capacity must be significantly higher to produce more when they are available, to match the same average production of a standard natural gas plant, which can have smaller reactors etc but work around the clock. I think hitting 5-6x cheaper costs on average might be hard.

Re: After many false starts, hydrogen power might now bear fruit

#327
post #75

Hydrogen has an efficiency problem. You need to convert other forms of energy to hydrogen at a loss. Then you need to store it and transport it, which is costly and may impose quite some energy cost for cooling or compression. Then you need to convert it back to electricity, also at a loss. If you start at electricity, the electrical grid and batteries would be much more efficient. If you start at oil or gas, you cou…

Many of the things you're saying aren't correct, see my other comment (sibling to yours) for references. Nuclear is not cheap compared to photovoltaics, wind and hydro. Since the former two are bursty, overcapacity in them leads to cheap excess energy at times, which needs to be stored. Which storage method is the best depends on multiple factors, particularly on the duration of storage, capacity required and frequen…

My favorite longshot in that direction is lifting carefully-shaped slobs of stone [0] up and down.

[0] https://omegataupodcast.net/299-gravity-storage/

Re: After many false starts, hydrogen power might now bear fruit

#328
post #283

Earlier quoted context omitted.

Amen. Not just bad faith; ignorant, myopic and ahistorical. > this sounds like a traditional government project problem -- susceptibility to corruption, vanity, hubris etc. said the person on a web forum (the web comes from CERN, a gov project) over the internet (the internet comes from DARPA, a gov project) on a computer (ever heard of the ENIAC? a gov project) Tech bros mouthing off off-topicly about the government…

> Amen. Not just bad faith; ignorant, myopic and ahistorical. Referring to GP's wikipedia reference, can you explain the two 'for unknown reasons' on a) why the original (Canadian) contract was not engaged, and b) the Turkish project was not engaged. What precisely was ashistorical about any of my post? > > this sounds like a traditional government project problem -- susceptibility to corruption, vanity, hubris etc.…

Please go grind your axe somewhere else.

Re: After many false starts, hydrogen power might now bear fruit

#329
post #75

Earlier quoted context omitted.

Many of the things you're saying aren't correct, see my other comment (sibling to yours) for references. Nuclear is not cheap compared to photovoltaics, wind and hydro. Since the former two are bursty, overcapacity in them leads to cheap excess energy at times, which needs to be stored. Which storage method is the best depends on multiple factors, particularly on the duration of storage, capacity required and frequen…

My favorite longshot in that direction is lifting carefully-shaped slobs of stone [0] up and down. [0] https://omegataupodcast.net/299-gravity-storage/

It's a long shot because it's a bad idea. It's fundamentally no different than pumped hydro, but much more complicated. I don't think there's any chance such ideas can work out.

Re: After many false starts, hydrogen power might now bear fruit

#330

Hydrogen has an efficiency problem. You need to convert other forms of energy to hydrogen at a loss. Then you need to store it and transport it, which is costly and may impose quite some energy cost for cooling or compression. Then you need to convert it back to electricity, also at a loss. If you start at electricity, the electrical grid and batteries would be much more efficient. If you start at oil or gas, you cou…

The problem you're missing is cost of production: A hydrogen car fundamentally should cost no more than gasoline powered car, and will have a similar range. With batteries, you'll always be limited in range to some extend, and cost reductions have failed to reduce them to anything like a Toyota Corolla type of car.

Batteries don't have a rare earth metal problem, they have a normal metal problem. You need a lot of raw materials to make them, and it's plausible that this will never scale to point where everything can run on batteries.

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