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Cheap, green hydrogen would be a breakthrough in clean energy

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Re: Cheap, green hydrogen would be a breakthrough in clean energy

#251
post #249
post #247

Earlier quoted context omitted.

Hydrogen leak because it's damn small, so you tank can hold it as a not-watertight tank can hold water, for a certain amount of time but not forever. We have tempted various routes, micro-foams included, none succeed completely. Surely as long as there is no accumulation risk H₂ leaks are harmless, but you still loose something valuable for you. kWh also matter MUCH: personally I can potentially produce just few gram…

kWh matters MUCH to you, not to reasonable people. If you need more H2, use a better electrolyser, or add another panel or two. The fact is, your numbers are all way off, so do not produce sensible judgments. They make you seem nutters. Get better numbers.

Oh, so if I change my numbers mother nature do the same?

"my numbers" are not mine, but from the current state of research on the field. The current state is simple: we can produce green hydrogen but in too little quantities, that means:

- we can't use it on scale

- there is no point in using it at smaller scale

That's why kWh count, because panels are not "toll free" coming like fruits on some tree branches, they have to be produced and they have a cost. They have a usable life, they need to be decommissioned after that. Actually we can make a single family home hydrogen+p.v. in certain area of the world, such home will cost few MILLIONS, need a variable amount of land from an hectare to few hectares, and last at around 10 years without special maintenance. We can produce few of them for the 1% of the humanity. Unfortunately such humanity can't keep up the species nor can't produce the aforementioned tech in their backyard, that's is. Is it more clear now?

We can do many things in general, some can scale, some can't, some are reasonable some are not. A green hydrogen industry so far is not reasonable and can't work on scale. We can continue researching on it of course, but we need working things, not dream, so we need something else to keep up.

Re: Cheap, green hydrogen would be a breakthrough in clean energy

#252
post #251
post #249

Earlier quoted context omitted.

kWh matters MUCH to you, not to reasonable people. If you need more H2, use a better electrolyser, or add another panel or two. The fact is, your numbers are all way off, so do not produce sensible judgments. They make you seem nutters. Get better numbers.

Oh, so if I change my numbers mother nature do the same? "my numbers" are not mine, but from the current state of research on the field. The current state is simple: we can produce green hydrogen but in too little quantities, that means: - we can't use it on scale - there is no point in using it at smaller scale That's why kWh count, because panels are not "toll free" coming like fruits on some tree branches, they ha…

Your numbers are still crazy and wholly disconnected from reality.

Panels do not, in fact require "decommissioning". They last much longer than 10 years: warranties are 20 years, often more. Output may be degraded by up to 20% after that, but they continue producing. If cooled, they last longer.

You can buy an electrolyser off the shelf today and plug it into any outlet. Efficiency is at least 60%, and rising; recent advances, which will hit market soon, have pushed it over 95%. A hydrogen car is much, much lighter than a battery electric car, so requires less energy to operate, but typical conversion losses today are larger than the difference.

Nobody needs a hectare of panels for personal transportation use, whether for charging a battery electric car or synthesizing hydrogen for a hydrogen-electric car. A typical rooftop is plenty, at least in summer, depending on latitude. A private system sufficient to produce hydrogen for a car is in low tens of $thousands, not $millions.

None of the above has anything to do with "scalability", which is a utility concern. Utilities can make hydrogen at whatever rate they have bought electrolysers for. The only thing stopping utilities is that if they had money for electrolysers, it would be far better used to buy more panels.

Making shit up gives you bad numbers and false conclusions.

Re: Cheap, green hydrogen would be a breakthrough in clean energy

#253
post #219
post #180

Earlier quoted context omitted.

Technically it may be forgiving, but not economically. Imagine electrolyzer or ammonia plant that uses only 20% of full capacity on average because of using only peak electricity surplus. The rest 80% is basically wasted. Classical plant with higher capacity factor might still be more profitable even if it uses more expensive electricity.

There is nowhere that you would operate at only 20% utilization. Demand for ammonia will be so strong that, after enough renewable overcapacity is built out, you would run electrolysers off your other storage, 24/7. A nuke would, of course, produce exactly zero grams of ammonia for ten years. It would also require burning coal for those ten years. Ten years of coal is part of the cost never accounted for, like the pu…

(*) storage cost neglected

Re: Cheap, green hydrogen would be a breakthrough in clean energy

#254
post #177

Earlier quoted context omitted.

Ammonia seems too dangerous. With cheap electricity from solar and wind, cheap hydrogen seems like a better answer. Sure, it's not a perfect answer, but it seems better because it seems much safer. As recently as approximately 200 years ago steel was very expensive, as was aluminum. Now both of those materials are cheap and used in a plethora of applications. Cheap electricity will similarly enable us to cost-effecti…

A safety argument does not favor consumer-level use of hydrogen. Nor, of ammonia. But synthetic liquified hydrogen, produced at airports from power delivered on transmission lines at times when power is cheapest, and banked, will certainly come to drive aircraft where cost matters.

I think you are correct; I was very probably wrong. I did some research. NH3 (Ammonia) seems like it will be used, at least, to power large cargo ships in the near future.

I didn't realize that Ammonia is essentially a cheaper and easier way to store hydrogen.

Thanks for enlightening me! I appreciate it.

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