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> You appear unaware of the magnitude of the system that now supplies kerosene to aircraft. Not at all. That system has a huge advantage over what you're prop

> You appear unaware of the magnitude of the system that now supplies kerosene to aircraft. Not at all. That system has a huge advantage over what you're proposing because a) it's distributed, and b) the energy doesn't have to be put into the kerosene by the infrastructure, it's already there. > Getting electric power to airports will be an overwhelmingly smaller job than moving kerosene there With the power requirements you're talking about, you're genuinely better off generating it onsite. The national grid won't cope. ~30 conventional nuclear reactors in the 500MW range ought to do it. Your wind option looks like tripling the UK's current onshore capacity, and solar means replacing Slough with a 14kmx14km square of photovoltaics (tempting), assuming it's always windy and/or sunny. > Generating the power to send to it will be an overwhelmingly smaller job than exploring, drilling, pumping, transporting, refining, transporting again, and distributing petroleum products Again, distributed vs concentrated. You've got to do that work all in one place. > The equipment can be where the tanker trucks used to stop. Problem of scale again. If you need a supply equivalent to 34 of the current biggest hydrogen-producing plant to generate the hydrogen, a fair guess says that you need at least a double-digit multiple of the land area of that plant to do so. "Where the tanker trucks used to stop" doesn't really work unless you mean "the west half of Hounslow". Besides which, if we're winding down kerosene infrastructure while hydrogen ramps up, they're both in use at the same time, so no, the equipment can't be where the tanker trucks used to stop because they're still there. Can't have it both ways. If you're generating on-site, the rate you need to be generating H2 is high enough that you absolutely can't be faffing about with underground caverns. You need to be piping it straight into buffer tanks that will supply one (1) plane then get refilled while the next plane taxis up. > Measuring future industry against current output before any of it is built gives you bad numbers. And planning without taking account of basic physics is worse. All I'm doing here is using a rough guess at the current energy requirements for the current activity and using that as a guide for future requirements according to your layout which, I think, is fair. If you think there are economic assumptions which break that, say so. If there are social changes you need to happen in order for this to make sense, say so. Otherwise you're arguing with thermodynamics. Efficiencies may come into the picture; I've assumed they're a wash between hydrogen generation tech, the on-site power generation, and present-day gas-turbine jets but even if that's not the case it's tweaking round the edges. This whole picture looks at least an order of magnitude out from anything practical in every respect.

ncmncm 4y ago
Again: > You appear unaware of the magnitude of the system that now supplies kerosene to aircraft. Since that is an overwhelmingly larger effort than generating electricity by solid-state PV panels, automatically collected and distributed on the grid via transmission lines, and electrolysing and liquifying, and tanking hydrogen via completely automated machinery, your sense of outrage is wholly misplaced. Of course, pumping LH2 into aircraft would involve some manual work with hoses. That is the only place where people need to be directly involved. No drilling technicians, pump operators, ship crews, refinery operators, truck drivers. Obviously, when we do more work via the electric grid, the grid must be beefed up to handle the extra load. It is not honest to insist that the existing grid, unchanged, would need to shoulder increased load. If we need for it to carry more load, we augment it. That is overwhelmingly cheaper than pipelines, ships, and refineries. Synthesizing hydrogen may be done anywhere at any time. There is exactly zero benefit to synthesizing in one place and transporting it to another, vs transmitting the power and synthesizing in place. Of course each airport may synthesize its own hydrogen. There is also no benefit in centralizing synthesis. Where you need it, drop equipment there. Generating power is done where the power-generating equipment is. There is no benefit in doing that at the airport, instead of at a thousand places on the grid and sending it in via transmission line. Anyway, where do you imagine the airport would put its PV panels and wind turbines? Yes, we need more solar and wind farms. That is not a novel or insightful observation. The entire "pumping, transporting, refining, transporting again, distributing" process, with all of it manual labor and industrial machinery, completely vanishes. Your lack of need to be aware of all that manual work done daily does not mean it is cheap or easy. It is done reliably just because it is a mature process, but it is very, very far from cheap or simple.
- regularfry 4y ago
  Oh dear. Maybe I should be clearer. 1) The scale of the existing kerosene system is a liability to your scheme such as it is, not an asset, because both need to exist in parallel. You cannot reuse it. Costs are additional for any transition period, and can easily be high enough to make transition impossible. 2) The scale of the kerosene system is thermodynamically irrelevant. The relevant scale problem is that you need double-digit gigawatts available to planes on demand and on-site. That's the whole game. Where you put the solar, wind, or nukes to make that happen is your problem, not mine, but I can guarantee you that transporting XXGW into a single site over transmission line starts to look silly. "Do it at a thousand places on the grid" is a non-starter. That's why I gave you the benefit of the doubt and assumed that on-site was naturally beneficial for your scheme. My mistake, it won't happen again. 3) However you do this, you are doing this in addition to the power generation capability of the rest of the grid. I've talked about one airport. Taking the UK as a whole you need to have a proposal which, give or take, doubles electricity generating capacity for the entire country. That needs more than a dismissive "not a novel observation" jibe. The scale of that challenge means that it's on you to propose how to achieve that as part of the scheme. You have not made such a proposal, rather you prefer to accuse me of misplaced outrage and dishonesty when you have failed to clarify a critical part of your idea adequately. You're handwaving about manual work and implying, I have to assume, that one can take the vast flow of money currently spent on manual labour and use it to bulldoze any inconvenient laws of physics which happen to get in the way. I wish you all the best in that particular endeavour. 4) Either you generate H2 on-site with huge amounts of equipment, or you pipe from elsewhere at pressure. In the former case "drop the equipment where you need it" takes vast tracts of land next to the airport, as I pointed out, in addition to the space the airport already takes up and in competition with the housing (or whatever) that's already there. In the latter you manage high-pressure hydrogen over considerable distances. It's just not true to say there's no difference. Elsewhere you've tried to dodge this dilemma, but you do actually need to pick one. You can't say that the storage and transport problem is fine because you can generate on-site without acknowledging the amount of space that takes up, and you can't restrict piped supply to low pressure because of the sheer quantity of H2 you need to transport. We're done here. The scheme's not practical, you've got no adequate response to the problems with it, and I'm past caring any more.

ncmncm 4y ago

Again: > You appear unaware of the magnitude of the system that now supplies kerosene to aircraft. Since that is an overwhelmingly larger effort than generating electricity by solid-state PV panels, automatically collected and distributed on the grid via transmission lines, and electrolysing and liquifying, and tanking hydrogen via completely automated machinery, your sense of outrage is wholly misplaced. Of course, pumping LH2 into aircraft would involve some manual work with hoses. That is the only place where people need to be directly involved. No drilling technicians, pump operators, ship crews, refinery operators, truck drivers. Obviously, when we do more work via the electric grid, the grid must be beefed up to handle the extra load. It is not honest to insist that the existing grid, unchanged, would need to shoulder increased load. If we need for it to carry more load, we augment it. That is overwhelmingly cheaper than pipelines, ships, and refineries. Synthesizing hydrogen may be done anywhere at any time. There is exactly zero benefit to synthesizing in one place and transporting it to another, vs transmitting the power and synthesizing in place. Of course each airport may synthesize its own hydrogen. There is also no benefit in centralizing synthesis. Where you need it, drop equipment there. Generating power is done where the power-generating equipment is. There is no benefit in doing that at the airport, instead of at a thousand places on the grid and sending it in via transmission line. Anyway, where do you imagine the airport would put its PV panels and wind turbines? Yes, we need more solar and wind farms. That is not a novel or insightful observation. The entire "pumping, transporting, refining, transporting again, distributing" process, with all of it manual labor and industrial machinery, completely vanishes. Your lack of need to be aware of all that manual work done daily does not mean it is cheap or easy. It is done reliably just because it is a mature process, but it is very, very far from cheap or simple.

regularfry 4y ago
Oh dear. Maybe I should be clearer. 1) The scale of the existing kerosene system is a liability to your scheme such as it is, not an asset, because both need to exist in parallel. You cannot reuse it. Costs are additional for any transition period, and can easily be high enough to make transition impossible. 2) The scale of the kerosene system is thermodynamically irrelevant. The relevant scale problem is that you need double-digit gigawatts available to planes on demand and on-site. That's the whole game. Where you put the solar, wind, or nukes to make that happen is your problem, not mine, but I can guarantee you that transporting XXGW into a single site over transmission line starts to look silly. "Do it at a thousand places on the grid" is a non-starter. That's why I gave you the benefit of the doubt and assumed that on-site was naturally beneficial for your scheme. My mistake, it won't happen again. 3) However you do this, you are doing this in addition to the power generation capability of the rest of the grid. I've talked about one airport. Taking the UK as a whole you need to have a proposal which, give or take, doubles electricity generating capacity for the entire country. That needs more than a dismissive "not a novel observation" jibe. The scale of that challenge means that it's on you to propose how to achieve that as part of the scheme. You have not made such a proposal, rather you prefer to accuse me of misplaced outrage and dishonesty when you have failed to clarify a critical part of your idea adequately. You're handwaving about manual work and implying, I have to assume, that one can take the vast flow of money currently spent on manual labour and use it to bulldoze any inconvenient laws of physics which happen to get in the way. I wish you all the best in that particular endeavour. 4) Either you generate H2 on-site with huge amounts of equipment, or you pipe from elsewhere at pressure. In the former case "drop the equipment where you need it" takes vast tracts of land next to the airport, as I pointed out, in addition to the space the airport already takes up and in competition with the housing (or whatever) that's already there. In the latter you manage high-pressure hydrogen over considerable distances. It's just not true to say there's no difference. Elsewhere you've tried to dodge this dilemma, but you do actually need to pick one. You can't say that the storage and transport problem is fine because you can generate on-site without acknowledging the amount of space that takes up, and you can't restrict piped supply to low pressure because of the sheer quantity of H2 you need to transport. We're done here. The scheme's not practical, you've got no adequate response to the problems with it, and I'm past caring any more.