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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

#201
post #180
post #69

Earlier quoted context omitted.

Diverting money from building out renewables to building nukes, for whatever purpose, brings climate catastrophe nearer. If ever there was a process forgiving of intermittently available energy, it is chemical synthesis. The same money spent on wind and solar would produce a lot more ammonia. Conversion losses don't matter much when marginal cost of generation is near zero, as we get with renewables, but very much no…

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.

Any electricity demand that can be modulated is good for renewables.

Big plants have been doing this for decades, even before renewables were a thing. The new thing is computers making it cheaply automatable and networked so that e.g. a fleet of cars can organise their charging schedule via the internet.

But rising electricity demand isn't a problem for renewables and climate change, it is in fact a required and desirable part of a virtuous cycle.

So build the Green Ammonia plant and build the renewables to power it 100% of the time but have the option to turn your electrolysers down and sell a small percentage of that to the grid when market prices let you profit from that. It's a win-win-win, less gas peakers, more green electricity and green hydrogen.

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

#202

Funny how Bill Gates always talks about global warming, but then owns mega mansions, super yachts, and flies all over the world in private jets

It’s because reducing your personal footprint feels good but doesn’t achieve much globally.

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

#203
post #191
post #171

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I think you are probably right, but some references would really be helpful. Could you share any that you have handy?

(Strongly anti) https://michaelwest.com.au/carbon-capture-and-storage-epic-f... (Neutral to anti) https://www.abc.net.au/news/science/2021-11-06/carbon-captur... (Weakly pro) https://www.iea.org/commentaries/carbon-capture-in-2021-off-... (Strongly pro) https://www.globalccsinstitute.com/resources/publications-re...

I think this might be the greatest comment I have ever seen on HN or elsewhere. Thanks, I wonder if BillG has read all four of them before he made up his mind, or that he's one-sidedly informed.

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

#204
post #95
post #89

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Heh, this is how I know you didn't grow up on a farm. You ever see a leaking anhydrous tank and you run for your life.

My father reports feeding raw ammonia directly into furrows being cut. Yes, a leaky ammonia tank would be a problem, but it is not exactly odorless.

By the time you can smell it from a leaking tank depending on the speed of the spill you may already be inviting lung damage, if it overwhelms you you're as good as dead. With some regularity farmers here are overcome by ammonia that has pooled in manure storage pools.

This article starts up with 'three dead per year through fertilizer vapors, one breath and you are gone'.

https://www.rtlnieuws.nl/nieuws/nederland/artikel/5022231/no...

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

#207
post #57

Earlier quoted context omitted.

It's not a matter of efficiency but of scale: we can't produce enough hydrogen by hydrolysis even with all the electricity we can produce. On contrary probably we can made electric tools to substitute tractors. Something that demand a bit of investment but last FAR longer and can run only on p.v. the hard part there would probably be convincing farmers that they do not need tractors anywhere but only for very specifi…

This EU study suggests that we could produce enough hydrogen to fuel air travel with about 32 Pwh annually, which is maybe 20% of current global energy production. I am pretty sure your assertion is simply wrong. Converting to hydrogen would be expensive, possibly dramatically more expensive than other solutions, but it seems totally achievable. https://www.fch.europa.eu/sites/default/files/FCH%20Docs/202...

This honestly is not a study, in the scientific sense, it's a McKinsey made scenario (and they are definitively not skilled in anything industrial, they only deal with finance) of something McKinsey want and present in nice, high paid brochures to offer politicians a way to justify spending in this or this other area.

So far the very few experimental plants we have made have proven the fact that, yes, the process work on solar, eolic ec, but also the fact that producible volumes are FAR BELOW the demand, not because we do not have enough plants so far on scale, but because we can't have them on scale on Earth at the actual state of tech.

Beside that so far we still completely miss the hydrogen storage issue: we can't store hydrogen in ANY known form. We can fill tanks of it, it will leak out slowly with relevant safety issues, and with the biggest issue that a just filled tank will be essentially empty in few days.

People like to dream, like to deny the reality following dreams pushed by interested parties, but they are just dreams, with good outcome for some scammers for some period of time, disasters for the dreamers.

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

#208
post #91
post #57

Earlier quoted context omitted.

It's not a matter of efficiency but of scale: we can't produce enough hydrogen by hydrolysis even with all the electricity we can produce. On contrary probably we can made electric tools to substitute tractors. Something that demand a bit of investment but last FAR longer and can run only on p.v. the hard part there would probably be convincing farmers that they do not need tractors anywhere but only for very specifi…

You insist on this, but it is not, in fact, true. All that is true is that we have not yet built out enough electrolysis equipment to produce much hydrogen. But that is an empty fact; of course, before you build something, you don't have it yet.

Let's made a game: how much electricity in kWh you need to extract a liter / gallon of H₂? How fast H₂ leak from a generic tank/in what form you propose to contain it and how much energy such form demand.

With this data we can discuss scalability.

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

#209
post #184

Earlier quoted context omitted.

We do want and produce ammonia in immense quantities already, so no, it’s not reasonable to bet on cost going down significantly.

We produce it in immense quantity from fossil fuels and vent the fossil CO2 into the atmosphere. The price of which is forecast to go up. Green Ammonia is made from renewable energy, which is forecast to become cheaper. It also requires electrolysers which are ramping up production and are also predicted to fall in price as they get made at scale from cheaper components. So it's a fairly safe bet even if you don't be…

Ammonia production is already in billions of dollars, we produce 191 million tonnes

What is the basis in physics for your belief that ammonia can be produced more efficieblntly, and why was it not done already?

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

#210

Ammonia has been mentioned a few times in this thread, but I will expand a bit, because I believe it is the most promising hydrogen-based approach. Essentially, the idea is to use ammonia directly as fuel. There is an ARPA-E funded project (that I'm currently failing to find) that cracks ammonia into hydrogen and nitrogen using heat. They claim that they can create a mixture of H2 and ammonia that will burn at any re…

Just wanted to add some basic chemistry information as background

Hydrogen (H) can be split from water (H2O) with a by-product of Oxygen (O). Hydrogen is hard to handle logistically (as discussed elsewhere in the thread), and the real idea in "Power to X" is to include Hydrogen in another molecule with better logistics. Main contenders are Ethanol (C2H5OH, alcohol), Methane (CH4, ~natural gas), and Ammonia (NH3).

Ethanol and Methane are by far the nicest products: already used as energy carriers, easy to handle, relatively non-toxic, but they have one problem: They require Carbon (C) to manufacture in addition to Hydrogen. Even with increased atmospheric CO2 levels, CO2 concentration in the atmosphere is only on the order of 400 ppm and extraction is expensive.

Ammonia (NH3) is synthesized directly from Hydrogen and Nitrogen (N) which is makes up 70% of the atmosphere. The Haber-Bosch process used for this synthesis is a cornerpiece of industrial chemistry.

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