71–80 of 149 posts
How about Hybrid planes? Take a conventional Dreamliner or A320, and add batteries and electric engines. Plane takes off using fossil fuel (hard to electrify), and then switches to electric engines once at cruise altitude. This is best of both worlds, and provides additional redundancy...
side note: a few companies are also bringing back zeppelin, so far for freight/cargon (10s of tons) but also but slow public transport. Hindenburg drama aside, I find them superbly peaceful. see: https://www.youtube.com/watch?v=oxotOEZCh8g
How about Hybrid planes? Take a conventional Dreamliner or A320, and add batteries and electric engines. Plane takes off using fossil fuel (hard to electrify), and then switches to electric engines once at cruise altitude. This is best of both worlds, and provides additional redundancy...
I’d actually suggest the opposite. Planes cuuently need overpowered engines just for take off
Or we just stop flying arround the world for two-day trips.
I would love to not travel to go meet a client on the other side of the world. Unfortunately that’s often how business still needs to be done to win over the decision makers.
As a first step, they could make at least the take off and landing electric, that would help a lot with the noise and pollution around cities, i.e. where people live. I guess the batteries could be recharged during the flight for landing.
I remember reading one UK airline saved a huge amount of fuel just by towing their aircraft to the take off point rather than using the engines.
[0] https://en.wikipedia.org/wiki/EGTS
[1] http://aviationweek.com/commercialregiontabs-true/easyjet-te...
Earlier quoted context omitted.
Now that electromagnetic catapults are becoming a thing, perhaps they can be adapted for airliner takeoff. One supposed benefit is the ability to adjust the acceleration profile to reduce airframe fatigue, and probably improve crew comfort at the same time. If it's smooth enough for passengers, it'd save carrying quite a bit of fuel and batteries. I would have thought landing to be far less energy intensive (except p…
Not sure catapults are a great idea for commercial passenger service, unless they can handle rejected takeoffs in case of other mechanical problems on the aircraft. You don't want to be catapulted off the end of the runway if you have an engine failure shortly after the start of the take-off run.
It’s just a question of the energy density of batteries vs. fuel. We need a couple more battery breakthroughs before we get a fully electric commercial airliner.
Lighter planes are more efficient, and most airliners are not designed to land with their tanks full. They have a option to jettison their fuel in case of emergency.
It means that just matching the energy density of fuel is not enough, batteries must exceed it. Jet engines are also quite efficient: around 40% now, and it may reach up to 60% in the future. It means that the more efficient electric engine is less of an advantage compared to cars for example.
The only battery technology that seems viable in order to replace fuel would be lithium-air. Petrol is just too good at storing energy.
Right now, I'd say the only chance for a "zero-emission" plane would be using biofuels.
side note: a few companies are also bringing back zeppelin, so far for freight/cargon (10s of tons) but also but slow public transport. Hindenburg drama aside, I find them superbly peaceful. see: https://www.youtube.com/watch?v=oxotOEZCh8g
Pretty bad in high winds though.
It’s just a question of the energy density of batteries vs. fuel. We need a couple more battery breakthroughs before we get a fully electric commercial airliner.
There is more than that. Planes become lighter as they burn fuel, batteries don't become lighter as they drain. Lighter planes are more efficient, and most airliners are not designed to land with their tanks full. They have a option to jettison their fuel in case of emergency. It means that just matching the energy density of fuel is not enough, batteries must exceed it. Jet engines are also quite efficient: around 4…
Flow batteries can and open cycle fuel cells do; electric isn't just the kind of batteries that retain reaction products.
As a first step, they could make at least the take off and landing electric, that would help a lot with the noise and pollution around cities, i.e. where people live. I guess the batteries could be recharged during the flight for landing.
Takeoff is the hardest part requiring the most power, unfortunately.
So, we just need a catapult system for commercial aircraft (like used on aircraft carriers, only lower acceleration since you are doing it to reduce the amount of energy needed from the engines, not to shorten the take-off distance.)