71–80 of 144 posts
Hydrogen is dead on arrival because steam methane reforming will always be cheaper than electrolysis, it's basically a fossil fuel.
It will be cheaper until it isn't. Then, it won't be. Hydrogen electrolysed using zero-marginal-cost power from solar farms producing in excess of demand, on cheapest-conceivable electrolysers, will become cheaper than what depends on extracting, concentrating, and transporting NG.
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So technically it might be possible to do that. But I don't think the economics would work out for that. Mostly because your cost of hydrogen will then be linked to the cost of electricity coming in. Given the choice between hydrogen which will cost the base electricity prices + overhead of electrolysis plants and transportation or to just use a resistive heater, you would most likely pick the resistive heater since…
> base electricity prices + overhead of electrolysis plants and transportation IF the capital cost of electrolysis isn't too bad - and this paper suggests that it can be done more cheaply than the current use of platinum - then it's economical to run them with zero or negative cost electricity produced by renewables overbuild, then keep the hydrogen in tanks (another if) or convert it to actual natural gas via the sa…
I am not saying making hydrogen can't be economical utilizing cheap off peak rates. I just don't see it as economical for home heating or typical consumer transportation since there are alternatives that utilize electricity directly.
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As much as I’ve been rooting for nuclear, I think the ship has sailed. If newer advances can’t make it cost competitive with renewables plus some storage (I’ll get to that in a minute) then why would you ever deploy it. Renewables are really cheap and getting cheaper, so some combination of overbuild with storage is probably the winning formula. Storage is a little too expensive as lithium ion batteries, but there’s…
> I’m fond of pumped hydro, which we can do anywhere with a height difference Not really economical unless you've got some suitably-shaped geology to build most of the storage vessels out of. The lithium issues may be addressed by sodium-ion, which is now mature enough that you can buy it on aliexpress.
I'm seeing a lot of people here assuming that the purpose of green hydrogen is for fuel cells / automotive transport, but I don't see many people in this space talking about that anymore (except Toyota). Instead there is a lot more interest in using green hydrogen for industrial purposes or as a key building block for cleaner fuels like methanol. Currently green hydrogen is expensive to make and sucks to transport. B…
Or as an renewables energy storage for use in leaker plants.
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Existing aircraft will be wholly unable to compete on any route where LH2 aircraft operate, but it will take a long time to bring up the infrastructure for it. Expect it to appear first on select freight routes. Oddly, H2 aircraft seem to be promoted with inboard tanks. The natural place for the tanks is in nacelles slung under the wings, for safety. (Hydrogen would not fit in the wings.) Hydrogen tanks in an enclose…
I am fairly sure this is due to the necessity of having pressurized cylindrical storage for the hydrogen. Fitting that kind of tank into the wings is going to be hard.
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It will be cheaper until it isn't. Then, it won't be. Hydrogen electrolysed using zero-marginal-cost power from solar farms producing in excess of demand, on cheapest-conceivable electrolysers, will become cheaper than what depends on extracting, concentrating, and transporting NG.
What you describe still is uneconomical: building out solar farms to exceed demand.
But today it's not, and a lot of talk about hydrogen comes from the fossil fuel industry trying to delay adoption of renewables like solar.
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Too many efficiency losses. Let's compare a BeV and a hydrogen vehicle. starting with a fully renewable source of electricity. For the BeV, we lose 5-6% over transmission lines, 5% of that converting AC to DC, another 5% on losses charging the battery, then another 10% at the electric motor. That's ~75% efficiency from your starting electricity to your wheels. With hydrogen, you lose 30% to electrolysis, another ~25%…
That’s hardly a “scam” though. The use cases are simply different. Batteries are good. Transportable fuel is also good.
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Existing aircraft will be wholly unable to compete on any route where LH2 aircraft operate, but it will take a long time to bring up the infrastructure for it. Expect it to appear first on select freight routes. Oddly, H2 aircraft seem to be promoted with inboard tanks. The natural place for the tanks is in nacelles slung under the wings, for safety. (Hydrogen would not fit in the wings.) Hydrogen tanks in an enclose…
> Existing aircraft will be wholly unable to compete on any route where LH2 aircraft operate ? Are you suggesting this will be a result of regulatory action? Since it would most likely be more expensive for the first decade, even if I gave you a tap on the airfield labelled "free H2"
Obviously hydrogen has it's uses, but a large part of me feels the energy industry is stalling for time. Oil and gas is basically a subscription model, whereas electric cars and heat pumps are buy once, upgrade in x years or when broken model. With enough renewable energy and a few nuclear power plants, electricity should be ridiculously cheap and if they've got the space, the consumer can even generate their own. Th…
But it was never, and will never be "cheap".
Also not all places might be suitable for nuclear, for various reasons. Hydrogen might be a good option.
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> few nuclear power plants, electricity should be ridiculously cheap Nuclear has never managed to be cheap. The really big nuclear buildouts always had a national security subsidy: either for energy security (France), or for nuclear weapons (US, UK, USSR, China, and also France). This is partly why non-weaponizable reactor designs never became popular either. > They obviously don't like that, which is why they keep p…
As much as I’ve been rooting for nuclear, I think the ship has sailed. If newer advances can’t make it cost competitive with renewables plus some storage (I’ll get to that in a minute) then why would you ever deploy it. Renewables are really cheap and getting cheaper, so some combination of overbuild with storage is probably the winning formula. Storage is a little too expensive as lithium ion batteries, but there’s…
Because it can work rain or shine. Wind or no wind.
What happens if we have no wind and have a lot of clouds for a few weeks in an area? The storage is limited and nuclear can still produce. Yes, I understand other areas can likely pick up the slack, but nuclear doesn't have that issue. At a minimum nuclear is a good thing to have as a back up even if we have sufficient renewables.
Also, don't forget climate change is supposed to cause more extreme weather events. We don't know what impact that will have on wind and solar.