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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.
by angiosperm 3y ago
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 enclosed cabin is a formula for disaster.
- pjc50 3y ago> 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"
- angiosperm 3y agoIt is because the very large difference in fuel weight for a flight leaves radically increased capacity for carrying paying freight. As LH2 produced on-site at airports gets cheaper than Jet-A fuel, the gap widens.
- pjc50 3y agoI'd need to see the numbers on this on joule/kg, and then allowing for the increased tankage size.
- angiosperm 3y agoVolume is cheap, on aircraft. If a normal freighter today takes off with 25t of kerosene, the similar-sized LH2 craft needs only 10t of LH2. That means it can take an additional 15t of paying cargo.
- purpleflame1257 3y agoI 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.
- angiosperm 3y agoTanks would be wholly impossible to fit into the wings. Thus, the under-wing nacelles. But pressure cylinders are a non-starter, because they are heavy. Expect to see, instead, insulated, unpressurized LH2 tanks.
- biomcgary 3y agoThe common criticism of LH2 economics is the energy required for liquification. Are you assuming that this is taken care of by overbuilding solar/wind and creating LH2 opportunistically?
- angiosperm 3y agoMuch the way aluminum producers guarantee load for hydro power producers, airports will consume overproduction by nearby solar farms.
- ben_w 3y agoGiven the power requirements of flight — they're fuel efficient per passenger-kilometre, but they have a lot of passengers and go a long distance — planes are the only place[0] where I think "overproduction by nearby solar farms" just isn't going to be a thing. OPEC paving their deserts with PV and synthesising fuel (whatever that is: hydrogen, Sabatier methane, aluminium for burning) or just exporting that electricity along a 2m^2 cross section solid aluminium rod to the other side of the planet? Sure, plausible. [0] I was going to say "and rockets", but then I realised we don't launch anything like as many rockets as we fly planes, so even then rockets might still be running on green hydrogen or methane derived from it.
- TylerE 3y agoWhy do you believe it will be freight first? Historically, the new aircraft go to pax service, then get converted after 20 or 30 years.
- angiosperm 3y agoThat tendency will delay the transition. But the big economic benefit arises from being able to carry 40% more cargo because the fuel is lighter. Passenger aircraft capacity is maxed out when the seats are full, now that carrying freight in the same aircraft is not allowed. Also, it will take a long time for safety worries to be satisfied.