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Battery powered long distance flight is unlikely because gasoline/kerosene has 5 times the weight energy density of lithium ion. Short haul flights may be viabl

Battery powered long distance flight is unlikely because gasoline/kerosene has 5 times the weight energy density of lithium ion. Short haul flights may be viable. Hydrogen fuel cell planes even better because hydrogen has 3 times the weight energy density of jet fuel and 15 times lithium batteries.

selectodude 5y ago
Long-haul flights work because burning the fuel means that it’s no longer weight being carried. In terms of energy to carried weight ratio, it’s basically infinite.
Tagbert 5y ago
What you may see are efforts to convert short-haul flights to electricity where the limited range is less of an issue.
lazide 5y ago
Hydrogen is a non starter because of the need for heavy tanks no? Batteries are sealed contained
- JohnL4 5y ago
  Right. Liquid hydrogen is fluffy. Energy density by volume is 4 times lower than that of jet fuel. https://www.bbc.com/future/article/20210401-the-worlds-first-commercial-hydrogen-plane https://www.bbc.com/future/article/20210401-the-worlds-first...
nickik 5y ago
This is not true. It just requires rethinking the whole design of a plane. Density of energy is not everything. Batteries for example can be made structural, so they actually replace part of the weight of a plane, while kerosene has to be carried like cargo. ICE engines are far less efficient too. And the TWR of electric engines is better too. That again reduced the structural loads. Electric engines also don't need to oxygen and can potentially fly much higher, where there is less air resistance. Even if you can't get as far, the price to operate these planes will be so much lower, that for the waste majority of the market they will simply be cheaper. Maybe more trips with multiple stops. Maybe the very longest flights would still be out of reach with good lithium-sulfer batteries but I suspect at that point those flights will be economically not tenable anymore.

selectodude 5y ago

Long-haul flights work because burning the fuel means that it’s no longer weight being carried. In terms of energy to carried weight ratio, it’s basically infinite.

Tagbert 5y ago

What you may see are efforts to convert short-haul flights to electricity where the limited range is less of an issue.

lazide 5y ago

Hydrogen is a non starter because of the need for heavy tanks no? Batteries are sealed contained

JohnL4 5y ago
Right. Liquid hydrogen is fluffy. Energy density by volume is 4 times lower than that of jet fuel. https://www.bbc.com/future/article/20210401-the-worlds-first-commercial-hydrogen-plane https://www.bbc.com/future/article/20210401-the-worlds-first...

nickik 5y ago

This is not true. It just requires rethinking the whole design of a plane. Density of energy is not everything. Batteries for example can be made structural, so they actually replace part of the weight of a plane, while kerosene has to be carried like cargo. ICE engines are far less efficient too. And the TWR of electric engines is better too. That again reduced the structural loads. Electric engines also don't need to oxygen and can potentially fly much higher, where there is less air resistance. Even if you can't get as far, the price to operate these planes will be so much lower, that for the waste majority of the market they will simply be cheaper. Maybe more trips with multiple stops. Maybe the very longest flights would still be out of reach with good lithium-sulfer batteries but I suspect at that point those flights will be economically not tenable anymore.