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After many false starts, hydrogen power might now bear fruit

economist.com

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

#201

The explosion limits of hydrogen are very wide. I do not want to live in a world with a widely deployed hydrogen infrastructure. Stuff is going to blow up. People are going to die. Disclaimer: chemical engineer, German University.

People said that about electricity, too. A lot of people died. Houses burned. Norms were changed regarding cabling and earthing. Hopefully, whatever we decide to adopt as a technology will come with adequate safety norms.

While only tangentially related, a lot of people think about the Hindenburg accident when talking about either hydrogen or dirigibles. But those contain less fuel than an airplane, at least in terms of energy. And 35 people died, around a third. To contrast with airliner accidents. But it sure left a mark on collective psyche. And I agree that hydrogen is incredibly volatile and explosive, which isn't a good fit for every application.

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

#202

Earlier quoted context omitted.

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

Then what's the alternative? Kinetic storage is geographically limited. Th Sabatier process has end to end efficiency of ~30% not to mention it needs an external source of carbon dioxide. The remaining proposals are at the experimental stage (thermal storage, hydrogen storage).

Underground hydrogen storage is a demonstrated technology, not experimental. All that's required is scaling it up, and there's plenty of room to do that. The only real missing piece was sufficiently cheap electrolysers for use with intermittently available power, but that's coming along very fast now too, with rumors of costs as low as $200/kW in China (and a recent contract win of $350/kW from a European maker of alkaline electrolysis systems). This is more than adequate for hydrogen storage.

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

#203

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).

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/

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

#204

Earlier quoted context omitted.

I was wondering the same thing, from a density perspective. And similarly for airplanes. As planes and boats expend fuel, they get lighter, so less fuel is needed to move the second half of the journey, and less for the last quarter, etc. That “bonus” doesn’t work out with batteries, you need to move all the weight for all the journey. The energy density of batteries, to my understanding, just doesn’t add up correctl…

with batteries, you need to move all the weight for all the journey For metal-air batteries, one of the more promising areas of research, the problem is actually worse: the cells gain mass as oxygen is reacted with the metal anode, discharging the battery. https://en.wikipedia.org/wiki/Metal–air_electrochemical_cell For marine propulsion, heavy fuels are typically preferred (bunker fuel typically, thogh deisel and pe…

> For metal-air batteries, one of the more promising areas of research, the problem is actually worse: the cells gain mass as oxygen is reacted with the metal anode, discharging the battery.

That's interesting, thank you for the info. Having a different characteristic from the usual one might lead to interesting applications. For instance, airplanes use a lot of fuel for takeoff, as they pay double the price for the weight of their fuel: they need to carry it up, when they have the most. This could actually be a game-changer, I think.

That could also be exploited: raise the battery when it is charged, have it gain weight, generate electricity while lowering it. Perpetual motion doesn't exist, of course. But gaining a bit of extra mileage is theoretically possible here :)

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

#205

Earlier quoted context omitted.

I think you missed the point: even for diurnal storage the scale required amounts to a decade's worth of global battery production just to create capacity equal to 1/4th of just the US's daily electricity usage.

This is a very lame argument. Manufacturing capacity isn't some fixed constant of nature, it's whatever makes sense given the market for the product. So if there's a large market, a large manufacturing capacity will be created. https://cleantechnica.com/files/2019/04/2019-Q1-Growth-in-Gl...

Even if we assume that the production capacity will continuously increases at the predicted rate, think you missed the part where that was just the US's storage requirements. Global electricity consumption annually was 22.3 PWh in 2017, yielding 61TWh per day. And while battery production increases, so too does electricity demand. Even if we assume that battery production increases to 1TWh-2TWh per year by 2030 as per your link we're still taking about decades to achieve even 1/4th of the current (not 2030) daily electricity consumption even if 100% of battery production was dedicated to grid storage. And that's not possible because grid storage is going to be competing with electric vehicles and electronics. And again, by 2030 were going to be using more electricity than we are currently. The necessary capacity is increasing exponentially. Pointing out that battery production is predicted to increase doesn't alter the fact that the scale required is massive.

And this all this is ignoring the fact that batteries lose half their capacity after 300-500 cycles. Even if we're generous and say 1000 cycles that's still just 3 years for diurnal use (daily charge and discharge cycles).

This thread is being rate limited, reply in edit:

> I didn't miss that. Why do you think global manufacturing capacity will stop when it reaches what the US needs, and not expand to satisfy the global market? You think the manufactures are going to leave sales and profits on the table for no good reason

I can ask you the same thing: why do you think that global battery manufacturing capacity is unlimited? What makes you think that we'll have an unlimited supply of raw materials? The prevalence of metal deposits does not respond to the market. Increasing prices of lithium will make more people search for lithium deposits, but there's a finite number of said deposits.

And again, the projected increases in in battery production due to increased demand bring down the time to create enough capacity from a matter of centuries to a matter of decades. For batteries that last a few years if cycled daily.

> It also seems reasonable to expect at least one significant breakthrough in battery technology over the next 10-30 years, given how important a problem it is, and how many promising approaches there are already.

So our approach is to keep our fingers crossed and hope for a technological breakthrough. If that's the case we might as well just hope for fusion to work.

But most of us would prefer a solution that we know works rather than bet on the possibility of breakthrough. And right now the only two known means of generating most of a country's power from a carbon free energy source is through hydroelectricity and nuclear power.

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

#206

Earlier quoted context omitted.

This is a very lame argument. Manufacturing capacity isn't some fixed constant of nature, it's whatever makes sense given the market for the product. So if there's a large market, a large manufacturing capacity will be created. https://cleantechnica.com/files/2019/04/2019-Q1-Growth-in-Gl...

Even if we assume that the production capacity will continuously increases at the predicted rate, think you missed the part where that was just the US's storage requirements. Global electricity consumption annually was 22.3 PWh in 2017, yielding 61TWh per day. And while battery production increases, so too does electricity demand. Even if we assume that battery production increases to 1TWh-2TWh per year by 2030 as pe…

I didn't miss that. Why do you think global manufacturing capacity will stop when it reaches what the US needs, and not expand to satisfy the global market? You think the manufactures are going to leave sales and profits on the table for no good reason?

The growth in production is being controlled by the growth in the market. New factories can be added at very high rate if needed. You are treating the manufacturing capacity as some exogenous constraint rather than something that can be changed along with everything else.

To respond to your response: a universal aspect of mineral depletion arguments is that estimates are too low. Demand create supply as people are encouraged to go look for more, and to develop new ways to extract materials.

Consider that natural gas used to be though of as rare and limited, so much so that its use for power production was outlawed in the US!

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

#207
post #160

Earlier quoted context omitted.

Quoting the Wikipedia page cited above: > It required one litre of water to clean, each of 400,000 installed panels. A total 15 days cleaning cycle required, 124 million litres of water enough to sustain 9000 people, while rain in Cholistan desert is rare and far between. Providing such huge amount of water in desert terrain, became a challenging and daunting task for management team. Besides, the manual cleaning met…

This seems kind of like a bullshit excuse where they just didn't really want to fix the issue. There are a number of waterless cleaning systems that have been available for years, for example [1]. Additionally, why the hell would you throw away the water used for cleaning? Filtering the dust particulate out of the water is pretty straightforward (hell, you can go from muddy to fairly clean water with nothing more tha…

Agree. They could probably just have people walk around with blowers to blow the sand off.

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

#208

Earlier quoted context omitted.

> The cost of storing waste is miniscule. Then how come that not a single country has yet developed a method for storing their nuclear waste safely and permanently? From your first link: > The fuel is either enclosed in steel-lined concrete pools of water or in steel and concrete containers, known as dry storage casks. > For the foreseeable future, the fuel can safely stay at these facilities until a permanent dispos…

> Then how come that not a single country has yet developed a method for storing their nuclear waste safely and permanently? They have. Finland has built a disposal site: https://en.m.wikipedia.org/wiki/Onkalo_spent_nuclear_fuel_re... The US built the Yucca Mountain, but then Congress blocked its usage. This was done due to political posturing not technical concerns. Burying it in an area with no groundwater is a foo…

> They have. Finland has built a disposal site: https://en.m.wikipedia.org/wiki/Onkalo_spent_nuclear_fuel_re....

> In 2012, a research group at the Royal Institute of Technology in Stockholm, Sweden, published research that suggests that the copper capsules of KBS-3 are not as corrosion-proof as SKB and Posiva claim. The research group led by Peter Szakálos estimated that the copper capsules would last only about 1,000 years, instead of the 100,000 years claimed by the companies. According to the research results, corrosion in pure copper advances at about one micrometre a year, whereas KBS-3 depends on a rate of corrosion that is a thousand times slower. Independent research conducted in Finland has supported the results of Szakálos's group.

I said "safely and permantently".

> Yucca mountain is not in a geologically active area

> Nevada ranks fourth in the nation for current seismic activity.[78] Earthquake databases (the Council of the National Seismic System Composite Catalogue and the Southern Great Basin Seismic Network) provide current and historical earthquake information. Analysis of the available data in 1996 indicates that, since 1976, there have been 621 seismic events of magnitude greater than 2.5 within a 50-mile (80 km) radius of Yucca Mountain.[78]

> DOE has stated that seismic and tectonic effects on the natural systems at Yucca Mountain will not significantly affect repository performance. Yucca Mountain lies in a region of ongoing tectonic deformation, but the deformation rates are too slow to significantly affect the mountain during the 10,000-year regulatory compliance period.

So there is tectonic deformation in the area, but everyone who has a stake in the projects believes it won't be a problem. To me that sounds like the believe that the Challenger's O-ring couldn't cause problems.

> After 10,000 years the uranium is no more radioactive than it was when it was dug out of the ground.

Which is why I only mentioned shorter timescales.

> And when Yucca mountain is filled the entrances are blocked by meters of concrete - even if canisters are somehow get compromised the uranium still needs to magically get through several meters of rock and concrete to get out into the environment.

> The volcanic tuff at Yucca Mountain is appreciably fractured and movement of water through an aquifer below the waste repository is primarily through fractures.[73] While the fractures are usually confined to individual layers of tuff, the faults extend from the planned storage area all the way to the water table 600 to 1,500 ft (180 to 460 m) below the surface.[74] Future water transport from the surface to waste containers is likely to be dominated by fractures. There is evidence that surface water has been transported down through the 700 ft (210 m) of overburden to the exploratory tunnel at Yucca Mountain in less than 50 years.[75][76] > The aquifer of Yucca Mountain drains to Amargosa Valley, home to over 1400 people and a number of endangered species.[2] > Some site opponents assert that, after the predicted containment failure of the waste containers, these cracks may provide a route for movement of radioactive waste that dissolves in the water flowing downward from the desert surface.[77] Officials state that the waste containers will be stored in such a way as to minimize or even nearly eliminate this possibility.

We already know the waste containers degrade much faster than originally thought. There is a significant chance of contamination of the groundwater.

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

#209
post #160

Earlier quoted context omitted.

Quoting the Wikipedia page cited above: > It required one litre of water to clean, each of 400,000 installed panels. A total 15 days cleaning cycle required, 124 million litres of water enough to sustain 9000 people, while rain in Cholistan desert is rare and far between. Providing such huge amount of water in desert terrain, became a challenging and daunting task for management team. Besides, the manual cleaning met…

This seems kind of like a bullshit excuse where they just didn't really want to fix the issue. There are a number of waterless cleaning systems that have been available for years, for example [1]. Additionally, why the hell would you throw away the water used for cleaning? Filtering the dust particulate out of the water is pretty straightforward (hell, you can go from muddy to fairly clean water with nothing more tha…

I wonder how much of the 1L evaporates.

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

#210

Earlier quoted context omitted.

Do we really need long-term storage? Wouldn't it be cheaper just to overprovision production?

It's almost always cheaper to overbuild renewables than to use seasonal storage. Seasonal storage is used once a year, so if you can store a Kwh of energy for $1 it still increases the cost of the stored electricity by 4-5 cents per Kwh. Let's look at a 1 Kw average output. Assume that you have 6 Kw of solar, along with 18 Kwh of batteries. This will work fine 7-8 months out of the year, but will not be sufficient fo…

Crypto Mining Companies have already figured it out.

https://www.forbes.com/sites/christopherhelman/2020/05/21/ho...

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