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Cheap, sustainable hydrogen through solar power

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Re: Cheap, sustainable hydrogen through solar power

#91

Post by hef19898 »

theshrike79 wrote: post #88
hef19898 wrote: post #87

Earlier quoted context omitted.

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 fo…

Just before Covid I did consulting for a green hydrogen product, on logistics, supply chain and all that. And, in the low to mid volumes, the easiest way, which included distribution to smaller sites, was using carrier oil and standard oil tank containers. I would have to look the exact oil up again.

Also true, as soon as one hits high volumes nothing beats liquified gas or pipelines.

Re: Cheap, sustainable hydrogen through solar power

#92

Post by tomtomistaken »

otterley wrote: post #90
tomtomistaken wrote: post #83

Burning hydrogen will still create a lot of NOx. Not recommended for places where people live.

I think the idea is to use it as a fuel in a fuel cell, not to use it as a combustion fuel.

I don’t think so. Hydrogen is being burned the old fashioned way.[1]

[1]https://www.cleanegroup.org/hydrogen-hype-in-the-air/

Re: Cheap, sustainable hydrogen through solar power

#93

Post by __MatrixMan__ »

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.

That depends on how far away the center is and whether you trust the people between here and there.

Re: Cheap, sustainable hydrogen through solar power

#94

Post by uluyol »

hannob wrote: post #2

Having seen too many such announcements about promising green technologies, I tend to ask a few questions when seeing something like this. One of them is what state a technology is in (early research, announcement, small prototype, industrial scale prototype). It is not really clear from the article what the scale and state of this technology is, but at least from the pictures this looks like small and very early sta…

Unless it says otherwise, it's generally safe to assume that an article put out of a university is in the early research phase.

Re: Cheap, sustainable hydrogen through solar power

#95

Post by yowlingcat »

yummypaint wrote: post #61
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?

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…

This is all correct with the caveat around how you want your "features" to be defined and how you want your "bugs" to be defined. Most notably, that's around the grid.

Implicit in your assumption is that the grid is reliable, always on, not subject to geopolitical or climate risks, etc. "Inefficiently" converting solar power into otherwise portable fuel might be a feature rather than a bug for those living in conditions where the central grid is often unreliable. Before the past few years, I'd say that would generally be countries in the global south, but we've seen a lot more grid instability even in the US as of late.

Re: Cheap, sustainable hydrogen through solar power

#96

Post by fbdab103 »

xxs wrote: post #36
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?

10k is an absolutely wishful thinking - 10k is just the low end of a bog standard geothermal pump. Also what's the purpose of the ethanol (the rest are not useful, esp. hydrogen which has to be stored somewhere, ammonia is rather dangerous)? I can imagine making vodka alike - but beyond that, using internal combustion engine to burn it means an extremely very low efficiency to conserve enegy. The energy density is th…

Heh. Yeah, I was thinking that any kind of home synthesis operation was unlikely to offer a financial payback. Hence the low aspirational cost, but you are right that figure is laughably low.

Ethanol - easier to synthesize than gasoline (which is a complicated mixture of hydrocarbons). It has ~2/3 energy density of gasoline, which I do not think is horrible. I believe it is also less volatile and easier to store long-term.

Re: Cheap, sustainable hydrogen through solar power

#97

Post by Pigalowda »

xxs wrote: post #36
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?

10k is an absolutely wishful thinking - 10k is just the low end of a bog standard geothermal pump. Also what's the purpose of the ethanol (the rest are not useful, esp. hydrogen which has to be stored somewhere, ammonia is rather dangerous)? I can imagine making vodka alike - but beyond that, using internal combustion engine to burn it means an extremely very low efficiency to conserve enegy. The energy density is th…

Couldn't it just burn off excess hydrogen? It would just be H20 byproduct.

Re: Cheap, sustainable hydrogen through solar power

#98

Post by fbdab103 »

ajross wrote: post #76
midasuni wrote: post #66

Earlier quoted context omitted.

Why not just a 20kWh battery for energy time shifting. Or are you looking to sell the hydrogen?

The commenter's goal is presumably season-shifting, which is two orders of magnitude off from feasible battery capacity. In most areas in the US, a full-roof solar system will produce enough energy in aggregate to power the home's use year-round, but there's no way to get all those summertime watt-hours into the lines in winter when the panels are dark. But indeed, no, this just doesn't work. Best available efficienc…

No interest in storing a season's worth of energy which would be infeasible without a ludicrously over provisioned system. More -what could you do with spare capacity that is not trash-tier net metering? Generating liters of fuel weekly would be enough to power my ICE car (I rarely drive). Or being able to generate and store a ~week of liquid backup energy.

Such a system would be unlikely to ever payback for itself. Not deluding myself on that one.

Re: Cheap, sustainable hydrogen through solar power

#99

Post by ajross »

fbdab103 wrote: post #98
ajross wrote: post #76

Earlier quoted context omitted.

The commenter's goal is presumably season-shifting, which is two orders of magnitude off from feasible battery capacity. In most areas in the US, a full-roof solar system will produce enough energy in aggregate to power the home's use year-round, but there's no way to get all those summertime watt-hours into the lines in winter when the panels are dark. But indeed, no, this just doesn't work. Best available efficienc…

No interest in storing a season's worth of energy which would be infeasible without a ludicrously over provisioned system. More -what could you do with spare capacity that is not trash-tier net metering? Generating liters of fuel weekly would be enough to power my ICE car (I rarely drive). Or being able to generate and store a ~week of liquid backup energy. Such a system would be unlikely to ever payback for itself.…

Depending on where you live, simply electrifying your home and driving an EV should be enough to get you within a few percent of your peak summer output. You won't be wasting that much. Buy the heat pump water heater, the induction range, etc... Pick the low hanging fruit, then worry about using that last bit of juice in June.

FWIW: net metering seems like "trash tier" precisely because that summer PV excess really is mostly wasted (this is true for big panel farms too). The utilities were taking a huge haircut on the old 1:1 billing that California just rolled back. It wasn't sustainable.

Re: Cheap, sustainable hydrogen through solar power

#100

Post by fbdab103 »

__MatrixMan__ wrote: post #93
adrianN wrote: post #85

Earlier quoted context omitted.

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

That depends on how far away the center is and whether you trust the people between here and there.

Part of my thinking was for fully off-grid homes. Are we approaching a point where they could capture the excess for long-term storage? Batteries are not the answer.
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