4 ms·
Not really, it's more likely to be stored at low temperature to avoid embrittlement. Liquid Hydrogen has an energy density of approximately 120 MJ/kg, almost th
by kurthr 4y ago
Not really, it's more likely to be stored at low temperature to avoid embrittlement. Liquid Hydrogen has an energy density of approximately 120 MJ/kg, almost three times more than diesel or gasoline. Even with the cryogenic storage and reheating equipment it has comparable power to weight ignoring electrical motor efficiency advantages. Comparable flight hours do take up 2-3x more volume than diesel (including pumps and fuel cells), but at larger sizes (e.g. 737 and larger) most commercial flight distances are limited by weight rather than volume.
A lot of things come down to scale. Small drones can run reasonable distances on LiPo, which scales very badly to larger vehicles.
- kristopolous 4y agoRight. The strongest evidence is commercial planes will be exclusively hydrogen powered. Airbus is working on one right now https://www.airbus.com/en/innovation/zero-emission/hydrogen/zeroe https://www.airbus.com/en/innovation/zero-emission/hydrogen/... (I think 2035 is way too long - it needs to be done 10 years ago) What more there will be hydrogen fuel plants onsite at the airports Additionally you'll see hydrogen in similar large systems such as rail and earth moving equipment. Honestly the only question I have in the large vehicle systems is cargo ships. There's plenty of space and benefit to large solar wings expanding the vessel surface area that can fold up when necessary If you see the efficiency gains and cost reduction in commercial grade PV continue, it's going to be unit cost economically superior fairly soon. Alternatively there could be some mystery device that can get a net energy gain by processing sea water to hydrogen fuel. This doesn't look physically impossible but I haven't heard of any serious efforts to do so yet and personally I'd need a lot of convincing to be assured it wouldn't just be doing a new flavor of ocean polluting
- coderenegade 4y agoCargo ships will go with methanol or ammonia, both of which are easy to synthesise from green hydrogen. I'm more partial to methanol since it can be carbon negative and provides a market for the tremendous amount of waste we generate, but ultimately the most effective solution will win.
- kristopolous 4y agoContainment and leaks is a huge problem with those fuels
- ncmncm 4y agoMillions of tons of ammonia are synthesized, handled, and used industrially every year.
- kristopolous 4y agoThat doesn't project to a guarantee of safety for all use cases. Thankfully both our opinions are irrelevant on this.
- rbanffy 4y ago> Liquid Hydrogen has an energy density of approximately 120 MJ/kg 8 MJ/liter for liquid hydrogen vs. 32 MJ/liter for gasoline Size matters