4 ms·

They are: https://www.airbus.com/en/innovation/zero-emission/hydrogen/zeroe https://www.airbus.com/en/innovation/zero-emission/hydrogen/... The thing is - all

by hannob 5y ago

They are: https://www.airbus.com/en/innovation/zero-emission/hydrogen/zeroe https://www.airbus.com/en/innovation/zero-emission/hydrogen/... The thing is - all carbon free options for aviation come with their downsides. Producing hydrogen creates a lot more conversion losses than using batteries, so when you can get along with a battery you will. Hydrogen will likely be used in the mid-range sector though.

torginus 5y ago
True - but hydrogen is still immensely cleaner than the jet fuel powered planes we have today. And for aircraft the weight savings could lead to the aircraft carrying more useful cargo, which would probably offset the efficiency loss. Edit: The link you provided describes hydrogen-combustion engines, not fuel-cell airplanes, which is also a promising concept, but not what I'm proposing.
- nradov 5y ago
  That's generally not true in practice today. Most hydrogen is produced from fossil fuels, so in most respects it's not any cleaner than just burning the fuel directly. In theory it is possible to produce hydrogen from clean energy without using fossil fuels. But we're a long way from doing that at scale. There is no real weight savings from hydrogen fuel once you account for the tankage, plus the more powerful engines needed to overcome the additional drag from those larger tanks.
  - torginus 5y ago
    "No weight savings" - In a reply to another commenter, if we compare the tank of the Honda Clarity FCEV with the Model 3s battery, it seems that hydrogen is more than 3x more as wrt. space for the same energy output as batteries - so if they can fit those, these will fit as well.
  - ncmncm 5y ago
    LH2 tanks hardly weigh anything. You must be talking about compressed gas, which of course would be obviously useless for aviation. So when anyone mentions hydrogen in connection with aviation, they do not mean compressed gas.

by hannob 5y ago

torginus 5y ago

True - but hydrogen is still immensely cleaner than the jet fuel powered planes we have today. And for aircraft the weight savings could lead to the aircraft carrying more useful cargo, which would probably offset the efficiency loss. Edit: The link you provided describes hydrogen-combustion engines, not fuel-cell airplanes, which is also a promising concept, but not what I'm proposing.

nradov 5y ago
That's generally not true in practice today. Most hydrogen is produced from fossil fuels, so in most respects it's not any cleaner than just burning the fuel directly. In theory it is possible to produce hydrogen from clean energy without using fossil fuels. But we're a long way from doing that at scale. There is no real weight savings from hydrogen fuel once you account for the tankage, plus the more powerful engines needed to overcome the additional drag from those larger tanks.
- torginus 5y ago
  "No weight savings" - In a reply to another commenter, if we compare the tank of the Honda Clarity FCEV with the Model 3s battery, it seems that hydrogen is more than 3x more as wrt. space for the same energy output as batteries - so if they can fit those, these will fit as well.
- ncmncm 5y ago
  LH2 tanks hardly weigh anything. You must be talking about compressed gas, which of course would be obviously useless for aviation. So when anyone mentions hydrogen in connection with aviation, they do not mean compressed gas.