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Synthetic liquid methane would probably be more practical because it is so much more energy dense than hydrogen. Audi already has a pilot plant that does this.

Synthetic liquid methane would probably be more practical because it is so much more energy dense than hydrogen. Audi already has a pilot plant that does this. https://en.wikipedia.org/wiki/Power-to-gas https://en.wikipedia.org/wiki/Power-to-gas You can also run standard jet engines on biodiesel. https://en.wikipedia.org/wiki/Aviation_biofuel https://en.wikipedia.org/wiki/Aviation_biofuel Both options are far more realistic than electric airliners, which simply aren't possible with any battery technology which will exist in the foreseeable future. https://www.youtube.com/watch?v=VNvzZfsC13o https://www.youtube.com/watch?v=VNvzZfsC13o NASA's interest in electric aircraft is most likely motivated by the possibility of flying them on other planets. https://en.wikipedia.org/wiki/JPL_Mars_Helicopter_Scout https://en.wikipedia.org/wiki/JPL_Mars_Helicopter_Scout

llukas 7y ago
https://www.bbc.com/news/business-48630656 https://www.bbc.com/news/business-48630656 "This week's Paris Airshow saw the launch of the world's first commercial all-electric passenger aircraft - albeit in prototype form. Israeli firm Eviation says the craft - called Alice - will carry nine passengers for up to 650 miles (1,040km) at 10,000ft (3,000m) at 276mph (440km/h). It is expected to enter service in 2022." "Eviation has already received its first orders. US regional airline Cape Air, which operates a fleet of 90 aircraft, has agreed to buy a "double-digit" number of the aircraft."
- Already__Taken 7y ago
  Surely you can't fly with only 1 engine right on the wingtip even if it has the thrust?
  - pjc50 7y ago
    It has three engines, not 1?
    - Already__Taken 7y ago
      Yeh but the media on it keep banging on about having redundant engines. I don't think redundancy counts when if that one the fails is a wingtip.
- thescriptkiddie 7y ago
  Carrying 9 passengers 1040 km at 440 km/h is quite a lot different than carrying 180 passengers 6150 km at 840 km/h (Airbus A320). Because batteries do not get lighter as you discharge them (fuel tanks do), simply adding more batteries gets you rapidly diminishing returns. Short range electric aircraft already exist, but transcontinental flights are likely out of reach. And if you are only traveling 1040 km, wouldn't you be better off taking a train anyway?
benj111 7y ago
Has anyone got a sense of what the issues are with moving to bio fuels/ liquid methane for aircraft? It looks as if it's going to have to be at least a medium term solution, I havent really heard much talk about them though. Is that just because they aren't sexy compared to electric planes?
lrem 7y ago
Seeing the ecological catastrophe that biofuels are, I hope they never make planes fly on that. Entire ecosystems are being burnt down to replace them with plantations :(
- thescriptkiddie 7y ago
  Just because biofuel production is not currently done responsibly doesn't mean it can never be. The same sustainable organic farming techniques that are used to grow food crops can be used to grow fuel crops, and should be. And don't forget that most biodiesel is currently made from waste products like used cooking oil.
  - lrem 7y ago
    Our farming's sustainability, on a global scale, is best illustrated by Amazon being burned down to create more farmland.
sunstone 7y ago
On the other hand, Musk sees an electric plane in about 5 years so there are differences of opinion by people in the know. https://electrek.co/2019/07/01/tesla-electric-airplane-elon-musk/ https://electrek.co/2019/07/01/tesla-electric-airplane-elon-...
Merrill 7y ago
Looks like some of these proposals in the article are for hybrid systems with electric motor assist to the turboprop/fan during takeoff and landing so that the liquid fueled jet engine can be sized for the most efficient cruise at altitude.
MrBuddyCasino 7y ago
„In 2013 the round-trip efficiency of power-to-gas-storage was well below 50%, with the hydrogen path being able to reach a maximum efficiency of ~ 43% and methane of ~ 39% by using combined-cycle powerplants.“ Not great, not terrible.

llukas 7y ago

https://www.bbc.com/news/business-48630656 https://www.bbc.com/news/business-48630656 "This week's Paris Airshow saw the launch of the world's first commercial all-electric passenger aircraft - albeit in prototype form. Israeli firm Eviation says the craft - called Alice - will carry nine passengers for up to 650 miles (1,040km) at 10,000ft (3,000m) at 276mph (440km/h). It is expected to enter service in 2022." "Eviation has already received its first orders. US regional airline Cape Air, which operates a fleet of 90 aircraft, has agreed to buy a "double-digit" number of the aircraft."

Already__Taken 7y ago
Surely you can't fly with only 1 engine right on the wingtip even if it has the thrust?
- pjc50 7y ago
  It has three engines, not 1?
  - Already__Taken 7y ago
    Yeh but the media on it keep banging on about having redundant engines. I don't think redundancy counts when if that one the fails is a wingtip.
thescriptkiddie 7y ago
Carrying 9 passengers 1040 km at 440 km/h is quite a lot different than carrying 180 passengers 6150 km at 840 km/h (Airbus A320). Because batteries do not get lighter as you discharge them (fuel tanks do), simply adding more batteries gets you rapidly diminishing returns. Short range electric aircraft already exist, but transcontinental flights are likely out of reach. And if you are only traveling 1040 km, wouldn't you be better off taking a train anyway?

benj111 7y ago

Has anyone got a sense of what the issues are with moving to bio fuels/ liquid methane for aircraft? It looks as if it's going to have to be at least a medium term solution, I havent really heard much talk about them though. Is that just because they aren't sexy compared to electric planes?

lrem 7y ago

Seeing the ecological catastrophe that biofuels are, I hope they never make planes fly on that. Entire ecosystems are being burnt down to replace them with plantations :(

thescriptkiddie 7y ago
Just because biofuel production is not currently done responsibly doesn't mean it can never be. The same sustainable organic farming techniques that are used to grow food crops can be used to grow fuel crops, and should be. And don't forget that most biodiesel is currently made from waste products like used cooking oil.
- lrem 7y ago
  Our farming's sustainability, on a global scale, is best illustrated by Amazon being burned down to create more farmland.

sunstone 7y ago

On the other hand, Musk sees an electric plane in about 5 years so there are differences of opinion by people in the know. https://electrek.co/2019/07/01/tesla-electric-airplane-elon-musk/ https://electrek.co/2019/07/01/tesla-electric-airplane-elon-...

Merrill 7y ago

Looks like some of these proposals in the article are for hybrid systems with electric motor assist to the turboprop/fan during takeoff and landing so that the liquid fueled jet engine can be sized for the most efficient cruise at altitude.

MrBuddyCasino 7y ago

„In 2013 the round-trip efficiency of power-to-gas-storage was well below 50%, with the hydrogen path being able to reach a maximum efficiency of ~ 43% and methane of ~ 39% by using combined-cycle powerplants.“ Not great, not terrible.