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[deleted] t1_iy8l365 wrote

Reply to comment by kukukele in Rolls-Royce successfully tests hydrogen-powered jet engine by je97

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HillSooner t1_iy8vz7g wrote

That is highly misleading. Hydrogen in a form that can burn is not abundant. You have to put more energy in to separate hydrogen from things like water than you would get from burning the hydrogen.

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DrLongIsland t1_iy8ysay wrote

Correct. Unless Rolls Royce also just figured out how to build a flying nuclear fusion reactor, but I suspect the news would be much bigger in that case.

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Tonaia t1_iyajvt3 wrote

Considering Rolls Royce is working on space based nuclear reactors, I wouldn't dismiss the notion out of hand.

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MostlyPseudonymous t1_iy8lt7k wrote

Free hydrogen is actually shockingly uncommon anywhere we can actually safely acquire it.

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[deleted] t1_iy8mbgt wrote

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MostlyPseudonymous t1_iy8mf9m wrote

Actually it's incredibly energy intensive, so 'easy' is misleading. That's only one of the very major problems with hydrogen as a fuel. Electrolysis of water consumes more energy than combustion of hydrogen releases.

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Art-Zuron t1_iy8s0k4 wrote

That's why it wouldn't be useful for power generation for a country, but as a fuel for discrete things like jets. Renewables like wind and water, and nonrenewables like fission should make up the difference. And, if we can ever figure out fusion, we could get nuclear power out of water too.

It took more energy to make Petrol than you get out of it too. And it takes millions of years to make it at that.

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johnny_memetic t1_iy8r26a wrote

You mean the device we call, "the bomb"? We almost never ran it. We'd light off all of our O2 candles before we'd turn that fucker on.

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wrgrant t1_iy8whgz wrote

Why not, out of curiosity?

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johnny_memetic t1_iy9awsa wrote

It's a bitch to maintain, and it has a salient tonal at frequency AAAAARRGHHHHHHHHHH

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wrgrant t1_iy9cqwf wrote

Ah thanks, makes sense. Last choice to get oxygen then over anything else for the sake of the sanity of the crew lol

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hazelnut_coffay t1_iy9zdq9 wrote

you do know that the vast majority of hydrogen is manufactured via steam reforming rather than hydrolysis right? there’s a reason why O&G companies are pushing for hydrogen as the next energy source rather than renewables.

steam reforming is methane (ie natural gas) + water -> carbon monoxide + hydrogen

hydrolysis is an energy intensive process. meaning you need to put in more energy than you get out of it. it’s not sustainable at large scale.

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everybodydumb t1_iy8mt7t wrote

And we can stop using carbon

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hazelnut_coffay t1_iy9zs8m wrote

look up the process used to create most of the hydrogen right now. it’s called steam reforming. it uses natural gas. theres a reason O&G companies are pushing for hydrogen fuel cells as the next energy source.

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EmperorArthur t1_iyedkl0 wrote

Honestly, I'd rather just use a methane jet engine. We can make methane out of pure hydrogen and CO2 if we care enough (Mars), but for the most part we can use what we already have.

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Pesto_Nightmare t1_iy9fniu wrote

Fuels like gasoline and kerosene are cheap because they are energy dense products that we just need to pull out of the ground and clean up. Fuels like hydrogen are more expensive because we need to invest the energy that is later extracted by burning or through fuel cells. We technically can use electricity to split water to generate hydrogen, but that process takes electricity, which costs money.

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