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Cheap, sustainable hydrogen through solar power

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Re: Cheap, sustainable hydrogen through solar power

#81

Post by conradev »

fbdab103 wrote: post #19

I am waiting for the day when there is an affordable ( Is anything like that on the horizon? Or do all of these liquid fuel synthesis options require industrial pressures/volumes/input electricity so as to forever be out of reach from residential synthesis?

It’s just a matter of cost. Cost savings will come from improved efficiency and manufacturing innovation. You can make a lot of electrofuels in a distributed way:

Hydrogen (Water + Electricity): There are many containerized electrolysers

Ammonia (Air + Electricity): https://www.nitricity.co/

Methane (Air + Electricity): https://terraformindustries.com/

Re: Cheap, sustainable hydrogen through solar power

#82

Post by jonnycomputer »

surume wrote: post #80

Would we use these like regular existing solar panels on our rooftops? And does 10x efficiency mean that we could harvest 10x the power of what existing solar panels provide?

I do wonder about the potential of converting excess summer-time rooftop solar energy into storable liquid fuels of some sort (e.g. methanol) for winter-time heating.

Re: Cheap, sustainable hydrogen through solar power

#84

Post by slow_typist »

fsh wrote: post #31
slow_typist wrote: post #24

Earlier quoted context omitted.

And the hydrogen will still diffuse into the steel. And make it brittle so all bottles, pipelines etc have a limited lifespan compared to infrastructure for methane. And you always need pumps to get it from one containment into another because it stays gaseous all the time. Don‘t get me wrong, all these problems are technically manageable. But from the economic perspective the H2-hype is not reasonable at all. H2-app…

This is yet another misconception. Hydrogen embrittlement is due to atomic hydrogen being created in chemical reactions. Gaseous hydrogen consists of H2 molecules which do not lead to embrittlement [1]. [1] https://en.wikipedia.org/wiki/Hydrogen_embrittlement

Maybe embrittlement is the wrong terminus but nevertheless molecular hydrogen poses risks to steel-made components of methane infrastructure. See for example [1]. There is also funded research at Fraunhofer [2].

[1] https://www.twi-global.com/technical-knowledge/published-pap...

[2] https://www.lbf.fraunhofer.de/en/projects/hydrogen-cyclic-st...

Re: Cheap, sustainable hydrogen through solar power

#85

Post by adrianN »

cduzz wrote: post #68
yummypaint wrote: post #61

Earlier quoted context omitted.

You can effectively accomplish the same thing from an environmental perspective by running your house as efficiently as possible. If you already have home solar, you are reducing the amount of carbon put into the air by power plants. Since CO2 molecules are indistinguishable from each other, that carbon reduction could just as well have come from burning renewable synthetic fuel made at home. If you have a big solar…

You can't operate a car / tractor / hot air balloon with just an efficient house. Also, you can't run your house on an efficient house + solar over the 2-6 months the sun isn't in the right place (in the sky) for very long or when your panels are covered in snow for a week. An efficient house gets you to the table and is a multiplier, but long term energy storage is also really important for lots of people. Hydrogen,…

It's probably more efficient to centralize storing weeks worth of energy.

Re: Cheap, sustainable hydrogen through solar power

#86

Post by chiefalchemist »

adrianN wrote: post #85
cduzz wrote: post #68

Earlier quoted context omitted.

You can't operate a car / tractor / hot air balloon with just an efficient house. Also, you can't run your house on an efficient house + solar over the 2-6 months the sun isn't in the right place (in the sky) for very long or when your panels are covered in snow for a week. An efficient house gets you to the table and is a multiplier, but long term energy storage is also really important for lots of people. Hydrogen,…

It's probably more efficient to centralize storing weeks worth of energy.

Perhaps. But then that means the power lines need to be maintained, even when not in use. I'm not sure what the amount is, but it's probably not insignificant.

Re: Cheap, sustainable hydrogen through solar power

#87

Post by hef19898 »

jillesvangurp wrote: post #59
fsh wrote: post #20

Earlier quoted context omitted.

The talk is about liquefied gas. Bottled gas has way too low density to put it on a tanker. The losses are due to boil-off, not due to leakage.

In gas form, hydrogen is much worse. You need about 18 truckloads of hydrogen stored at 200 bar to match a single truck load of diesel in terms of energy.

You can also use certain oils to absorb (not sure if that is the technical correct term here) the hydrogen for transport. Renders it inert, no losses and it doesn't even count as dangerous goods for land and sea freight. Seems to be pretty easy to get the H2 out of the oil for use or transfer.

Re: Cheap, sustainable hydrogen through solar power

#88

Post by theshrike79 »

hef19898 wrote: post #87
jillesvangurp wrote: post #59

Earlier quoted context omitted.

In gas form, hydrogen is much worse. You need about 18 truckloads of hydrogen stored at 200 bar to match a single truck load of diesel in terms of energy.

You can also use certain oils to absorb (not sure if that is the technical correct term here) the hydrogen for transport. Renders it inert, no losses and it doesn't even count as dangerous goods for land and sea freight. Seems to be pretty easy to get the H2 out of the oil for use or transfer.

The man in the keynote I linked was "Michael Liebreich, Chairman and CEO of Liebreich Associates, through which he provides advisory services and speaks on clean energy and transportation, smart infrastructure, technology, climate finance and sustainable development. In September 2020, he became an official adviser to the UK’s Board of Trade".

...and he didn't know of any better ways of transporting H2 than liquid form.

If it would be "pretty easy" to absorb it to oils, I'm sure that would've been tried already.

the industry's goal seems to be hydrogen->ammonia - transport - ammonia->hydrogen, because ammonia is orders of magnitude easier to transport.

Re: Cheap, sustainable hydrogen through solar power

#89

Post by PaulDavisThe1st »

chiefalchemist wrote: post #86
adrianN wrote: post #85

Earlier quoted context omitted.

It's probably more efficient to centralize storing weeks worth of energy.

Perhaps. But then that means the power lines need to be maintained, even when not in use. I'm not sure what the amount is, but it's probably not insignificant.

I live in New Mexico with a 6.7kW array. My house is heated with air source heat pumps. In the summer, we generate 3x the electricity we need. In the winter, we generate 1/3x of the electricity we need. Last year we generated 91% of all our electricity, the year before 93%.

We would need a gigantic store for heating our house, because for 4-5 months a year, we are generating less electricity than we need. Something on the order of 15MW of storage.

We could certainly our home's thermal efficiency, though this would be complex. We could also add more panels, but then we'd be overproducing by even more during the summer.

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