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Airbus and Boeing are exploring the viability of electric planes
- cm2187 9y agoAs 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.
- tonyedgecombe 9y agoI 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.
- neurotech1 9y agoProbably related to Electric Ground Taxi System [0] which allows the APU(Auxiliary Power Unit, a small turbine driven generator) or potentially batteries to provide electrical power for taxiing. The APU also powers the air conditioning packs on the ground. The electric taxiing system was tested on Easyjet [1] [0] https://en.wikipedia.org/wiki/EGTS https://en.wikipedia.org/wiki/EGTS [1] http://aviationweek.com/commercialregiontabs-true/easyjet-test-honeywellsafran-electric-taxi-system http://aviationweek.com/commercialregiontabs-true/easyjet-te...
- achamayou 9y agoNow 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 perhaps in case of aborts, but I would imagine they're reasonably uncommon).
- bdonlan 9y agoAlthough missed landings are uncommon in commercial service, every flight has to carry enough fuel for multiple missed landings, just in case.
- ams6110 9y agoNot 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.
- achamayou 9y agoThat doesn’t sound fundamentally different from having a failure on one engine sufficiently late during takeoff. Either way you probably want your other engine to have enough power to make a landing?
- pjc50 9y agoTakeoff is the hardest part requiring the most power, unfortunately.
- dalore 9y agoBut they are also close to the main grid so could charge up a big capacitor from the mains to get a boost.
- usrusr 9y agoTakeoff, and landing abort. It might turn out to be economical to have hybrid engines that are fully optimized (in efficiency and in drag) for sustained climb load (or even just to cruise) that can only deliver takeoff/abort thrust using electrical assist. It could be enough to carry batteries for no more than a few minutes of assist! I don't know though how much the efficiency of current jet engine drops off at the far ends of their throttle range.
- dragonwriter 9y ago> 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.)
- dalf 9y agoWhy not something similar to railgun but at a slower speed. This would involve few things on the plane. The draw back is that airports needs to install this system. During take off, if there is a problem, the system could be stopped. Perhaps it's not usable in this context ?
- dllthomas 9y agoMagnetic media on the plane might be unhappy.
- zeusk 9y agoLandings are mostly idle power until they lower landing gears in the last few miles; Take-off with fuel load is the most demanding leg and also the hardest to electrify.
- whitepoplar 9y ago...until they're not (e.g. failed landing, go-around)
- zeusk 9y agoYes, my point being - there is no gain in electrifying that part and more risk in cases you mentioned.
- ubernostrum 9y agoIt's also worth noting that the range of an airliner depends heavily on the fact that it becomes lighter en route through burning fuel. At takeoff, nearly half the mass of the aircraft can be fuel. Batteries don't provide that kind of mass reduction as they discharge, which means long-range flight using only batteries as a power source is rather unlikely.
- Infernal 9y agoIf you compare to hybrid cars, landing is more like braking to a stop light (unless you need to gun it again to abort the landing). Takeoff is like accelerating from a stoplight (where you need the most power). If electric could take over at any point, it would be in the steady cruise at altitude (akin to overdrive on the highway).
- taneq 9y agoGoing by your hybrid car analogy, electric would make most sense as a brief power boost on takeoff, allowing the aircraft to use smaller, lighter engines to cover cruising power requirements more efficiently.
- savrajsingh 9y agoIt’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.
- Shivetya 9y agopretty much what many in motorcycling are waiting to see happen. a hundred and at most hundred fifty but that requires judicious use of acceleration and speed. cars and trucks can carry the mass but if anything screams "this tech isn't there yet" it is the weight to range ratio we have now in cars. yeah we can build them but looking back twenty years from now should be really interesting
- mattnewton 9y agoWe’re getting there with motorcycles too- they are expensive but starting to get useable ranges with today’s battery tech: http://www.zeromotorcycles.com/range/ http://www.zeromotorcycles.com/range/ Plus, they sound like pod racers from the future.
- mpweiher 9y ago> energy density of batteries vs. fuel For short-haul flights, this matters a lot less.
- knolan 9y agoYou also expel all that burnt fuel reducing weight was you fly. Some aircraft even redistribute fuel between tanks to control stability and performance. [0] [0] https://www.amevoice.com/blog/1058/airbus-a340-fuel-system-distribution-briefing/ https://www.amevoice.com/blog/1058/airbus-a340-fuel-system-d...
- skookumchuck 9y ago> Some aircraft even redistribute fuel between tanks to control stability and performance. Aircraft have been doing that forever. Carefully managing the fuel flow from which tank has always been a task for the pilot.
- realPubkey 9y agoOr we just stop flying arround the world for two-day trips.
- sjilo 9y agoI think we should now be at a point where we realize that people won't give up these benefits to their lives "for the greater good". Convincing people to go green as a business model would be a huge failure - nobody would pay to get convinced to stop doing something convenient.
- geff82 9y agoThat is what I always say! Teslas, for example, are not becoming so popular because their owners are all environmentalists. They got so popular because they are extremely fun to drive and save on fuel a lot while not restricting their owner in range. I for example, recently reserved a Model 3, but I would not stop flying. But I would choose the airline that first provides me with a calmer and less smelly airplane any time. Ä
- pouetpouet 9y agoThat's what pigouvian taxes and other steep carbon taxes are for
- dbasedweeb 9y agoSo make them pay for externalities, and you’ll see the necessary reduction.
- amelius 9y agoOr add a large tax to flying that pays for the development of green solutions.
- patrickaljord 9y agoThis way only the super rich will be able to fly.
- cyberferret 9y agoThe stat that really woke me up to how popular travel was when an aviation magazine once posted that at any second of any day, there are at least one million people flying in an airplane somewhere. That's an entire good sized city full of people who are not in contact with the ground at any point in time you care to pick. And that article was quite a few years old, I wouldn't be surprised if that number has increased significantly lately. That should bring some perspective to the environmental impact of transporting that many people around the globe.
- kzrdude 9y ago..and it's reassuring me of the safety of aviation.
- cyberferret 9y agoThat is a huge positive aspect. Whenever anyone I know laments an air crash somewhere in the world, I just say to them "Right now, there are over 1 million people airborne, and who will arrive at their destination safely. The same will happen in 10 minutes, in an hour, in 6 hours, and tomorrow".
- FabHK 9y agoIt's said that 1000+ Boeing 737 alone are airborne $NOW.
- Someone 9y agoThat’s likely true. They produced the 10,000th 737 in March, so if each plane were airborne eight hours a day (not unrealistic for commercial planes), two thirds of all 737s produced could be out of service to get at that 1000 ⇒ I would guess that actual number is closer to 2000, possibly even over iT.
- bluedino 9y agoOver 1200 737-800’s alone https://flightaware.com/live/aircrafttype/ https://flightaware.com/live/aircrafttype/
- kzrdude 9y agoNorway is in an ideal position; a surplus from oil money and excessive access to hydro power. I would hope they can use their current oil prosperity to prepare for a hydro (and other green energy) powered future, in all kinds of new places. After I typed that I realized that the whole world could be said to be in oil prosperity still, so the same applies to us all: with less evenly distributed oil prosperity, and not every species of green energy available everywhere.
- FiveSquared 9y agoBut that will never happen in the USA due to the influence of the oil industry.
- ubernostrum 9y agoYou may be interested in the Norwegian TV series "Occcupied": https://en.wikipedia.org/wiki/Okkupert https://en.wikipedia.org/wiki/Okkupert The premise is that Norway develops thorium reactor technology and ceases all fossil-fuel production. And then is clandestinely and later openly invaded by Russia, with the blessing of other countries, to seize oil and gas production facilities and forcibly re-open them.
- sitkack 9y agoOil is always a liability. It would be better to claim you ran out. But the Russian subearth nuclear boring machines don't need to invade.
- na85 9y ago>Russian subearth nuclear boring machines The what now?
- rlkf 9y agoOff-topic, but still: There are several frightening realistic aspects with that series, but the key premise - that the U.K. would willingly allow Russia to take control over one of its energy sources - is so utterly bonkers that it spoils the rest.
- jopsen 9y agoFrom an engineering perspective how much harder would be to do a cross Atlantic high speed rail: Norway <-> Canada ? Politically, it would probably be possible due to cost and risks.
- hengheng 9y agoTectonics would like a word with you
- zdkl 9y agoYou don't have to bolt it to the ground though!
- tonyedgecombe 9y agoAt it's deepest point it's about 8.5km down, for every 10 m of depth you add one atmosphere of pressure ... It would probably make more sense to go overland in the opposite direction, through Russia, Alaska and Canada.
- pacaro 9y agoHarry Harrison covered this idea in “A Transatlantic Tunnel, Hurrah!” [1], which only had to compete with coal powered flying boats and nuclear trains. [1] https://en.wikipedia.org/wiki/Tunnel_Through_the_Deeps https://en.wikipedia.org/wiki/Tunnel_Through_the_Deeps
- wongarsu 9y agoThe tunnel could be partially floating (or rather bridging over deep parts of the sea floor). Continental drift shouldn't be a big problem over a few decades, you will need some expansion joints anyways.
- pjc50 9y agoThe Channel Tunnel cost ~£200m per mile. The Atlantic is ~4000 miles across. That implies the Atlantic crossing would cost £800bn, slightly more than a trillion dollars and roughly the cost of the Iraq war and occupation.
- hyperpallium 9y agoIt's weird, recently a solar plane circumnavigated the globe, but got very little publicity.
- bpicolo 9y agoYou can't scale up solar power to an aircraft carrying significant passengers / cargo.
- lucb1e 9y agoDo you have anymore information on that, a link perhaps?
- kurthr 9y agoThe weight for the mass of the passengers scales with the volume (m^3) while the area of the solar cells (and wing) to lift them scales with m^2. The typical solution for human scale aircraft is to fly faster (higher stall speed) and extend the length of the fuselage. Unfortunately, that combination doesn't increase efficiency so you end up needing even more fuel (or area and weight for batteries and PV). The demonstrated PV aircraft are already pushing the lowest wieght, lowest drag wings with the highest efficiency PV and energy dense Batteries. This is a case where bigger is harder (not so with Zeppelins where structural material weight/stiffness scale to much larger sizes).
- dreamcompiler 9y agoYou can't do it with cars, either. Solar-powered cars are definitely a thing [1], but they're purely research vehicles. At 20% efficiency, PV cells will never power a practical car any consumer would want to buy. Nor would such cars likely be road-worthy on normal highways. The engineering and physics challenges are even tougher for passenger aircraft. It ain't gonna happen. [1] https://en.wikipedia.org/wiki/Sunraycer https://en.wikipedia.org/wiki/Sunraycer
- cagenut 9y agoIf you're interested in the electrification of flight check out this episode of Fully Charged: https://www.youtube.com/watch?v=Xe1g1JrRRkY https://www.youtube.com/watch?v=Xe1g1JrRRkY Its kindof like a "roadster" for the sky. I was really impressed by the contra-rotating prop opportunity that becomes possible because of how small electric engines are (for their power).
- Bromskloss 9y ago> I was really impressed by the contra-rotating prop opportunity that becomes possible because of how small electric engines are (for their power). Did that really have to do with the electric motors? They even gave an example of a combustion engine plane that did the same.
- mrfusion 9y agoI feel like it would chop up The air too much for the second propeller?
- andlier 9y agoThe issue with the «chopping» is noise level. Counter rotating propellers are more efficient than a single propeller. «Contra-rotating propellers have been found to be between 6% and 16% more efficient than normal propellers.» https://en.m.wikipedia.org/wiki/Contra-rotating_propellers https://en.m.wikipedia.org/wiki/Contra-rotating_propellers
- hanklazard 9y agoFor anyone not aware, YC grad Wright Electric is in this space: https://weflywright.com/ https://weflywright.com/
- agumonkey 9y agoside 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 https://www.youtube.com/watch?v=oxotOEZCh8g
- ams6110 9y agoPretty bad in high winds though.
- agumonkey 9y agoI wonder if they accounted for that
- CalRobert 9y agoWith a remote work arrangement it would be lovely to travel by Zeppelin (or ship, or train, for that matter).
- agumonkey 9y agoyou mean slow moving working space ?
- wongarsu 9y agoI can totally see them in helicopter-like roles for heavy cargo. I have my doubts about the viability of public transport. In the times of the Hindenburg the zeppelin was already becoming obsolete. If you wanted comfort ships could provide much more because weight was a major issue for zeppelin interiours, and if you wanted speed planes were already several times faster. The high number of crew combined with slow speeds (i.e. long travel times) meant that zepellin tickets weren't cheaper than either of the two alternatives. With both ships and planes significanlty better than 80 years ago I don't see how economics should be more in favour of zepellins now. There's novelty value, but that didn't keep the Concorde flying either.
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- Alyosha_ 9y agoI can see playing and winning against ICE with electric motors, but against the efficiencies of a turbine? Ummmm....
- nine_k 9y agoElectric engines are about 98% efficient. What's hard to beat is the energy density of kerosene.
- lumberjack 9y agoIt would make infinitely more sense to look into carbon neutral hydrocarbon fuels that could be used in conventional turbofans. Some more material on this topic: https://aviation.stackexchange.com/questions/26910/could-an-electric-engine-provide-the-same-performance-as-jet-engines-on-current https://aviation.stackexchange.com/questions/26910/could-an-...
- ShorsHammer 9y agoAnother SE link of interest, how much electrical power needed to run a 747 engine: https://aviation.stackexchange.com/questions/19569/how-many-kilowatts-to-get-an-electric-747-8-airborne https://aviation.stackexchange.com/questions/19569/how-many-... The consensus is ~90 MW. That's a lot of energy, electric air travel is certainly possible, but it will likely come at a severe cost to speed and endurance. If we are going to travel slowly would personally prefer autonomous airships.
- TheSpiceIsLife 9y agoMegawatts is a power unit. To sustain 90MW for a 4hr flight you need a battery that can provide 360MWh of energy. Anyone care to do the numbers on how much a lithium ion battery would weigh to be able to deliver 360MWh, and remember if you want to use it more than once you can full charge no discharge it.
- Hextinium 9y agoA standard lithium ion battery has between 100-265 Wh/kg if you need 360 thousand to 135 thousand kg of lithium ion batteries plus probably a few thousand for charging equipment. A a 747 has capacity for about 45k kg of fuel so a factor of 4 improvement is needed before that is comparable.
- ShorsHammer 9y agoThe energy density of most fossil fuels is still far beyond anything we've managed through incremental improvement on 1900's battery technology. There's much more work to be done.
- DelaneyM 9y agoThe only plausible near-term renewable-energy flight option I can see is hydrogen fuel cells powering electric planes. The equipment is heavy, but compressed liquid hydrogen is both producible from renewable sources and has a significantly higher energy/weight ratio than traditional fuel. It would require a few advances in fuel cell technology, but that's totally plausible.
- exebook 9y agoArticle says that the electric powered planes need shorter runways, why is that?
- Zhenya 9y agoInstant maximum torque most likely. I guess they are assuming equal or less weight for the plane
- mveety 9y agoYeah the torque is probably the reason. From experience, if you stand on your brakes and throttle to take off power then let go your take off performance is better. It's part of the short field take off procedure.
- DoctorOetker 9y agoperhaps a rear propeller for deceleration, to recharge the batteries? :P
- FiveSquared 9y agoA related YouTube video about the subject: https://youtu.be/ql0Op1VcELw https://youtu.be/ql0Op1VcELw
- reacharavindh 9y agoHow 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...
- mrfusion 9y agoI’d actually suggest the opposite. Planes cuuently need overpowered engines just for take off
- ams6110 9y agoIt will still never make sense until battery energy density increases a lot more. Boost power for takeoff is still going to be cheaper weight-wise burning kerosene than with electric batteries.
- m_mueller 9y agoHow much of a Tesla‘s battery is drained after a drag race? Electric seems to be quite good at delivering boost. See also the current generation of supercars from Porsche, Ferrari and McLaren.
- icegreentea2 9y agoThe problem is that then the battery and the entire electric half of the hybrid system is then deadweight for the rest of the flight. Now that doesn't mean it's not viable, but it's going to be a difficult calculation to make without actually have specs in front of you. The catapult solutions elsewhere in the thread seem to make more sense. But once again we're all back to actually having to do the math on these. Commercial flight is viable because the engineering safety factors and economic margins are so close to 1. This means that changes actually have to be considered carefully, unlike some other fields where the greater safety factors and margins let you get away with more assumptions.
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- Apocryphon 9y agoMusk-Stark efforts bear fruit? https://www.youtube.com/watch?v=Y9BUcjuW-_A https://www.youtube.com/watch?v=Y9BUcjuW-_A
- toomanybeersies 9y agoAirbus actually made a prototype electric ducted fan plane: https://en.wikipedia.org/wiki/Airbus_E-Fan https://en.wikipedia.org/wiki/Airbus_E-Fan The core problem with it though was the poor energy density of batteries. Hopefully electric cars will drive more innovation in this area, although the aviation industry is usually at least 20-30 years behind the automotive industry as far as engine technology goes, so we're probably 40 years away from getting widespread adoption of electric aircraft.
- greglindahl 9y agoIf you'll recall, Boeing used pretty modern LiIon batteries in the B787 and it caused a few fires. That appears to have been a design mistake that no car manufacturer has made, but it still sets a standard for what aviation needs to do if they want to be closer to the bleeding edge.
- Retric 9y ago> behind the automotive That's far from true, large aircraft engines are vastly more efficient than automotive engines. Small aircraft are such a tiny market they effectively get zero R&D. Interestingly hybrid cars could be significantly improved fuel efficiency using turbine engines though at increased costs. Plug in hybrids may actually see the adoption due to lower weight and lower useage making those tradeoffs less meaningful.
- ajross 9y ago> so we're probably 40 years away Batteries will never get there, even in four decades. There's no known battery chemistry, even in theory, that even comes close. Fuel cells would have to be the power source, though fuel cells are like fusion in that they're always a few decades out. Frankly if the real goal is having aircraft flying on renewable power, I'd put my money on using that clean energy at sea level to synthesize fuel to burn at altitude. Aviation just isn't a meaningful application of electric motors IMHO.
- kwoff 9y agoI'm not sure how on-topic this is, but this story/topic reminds me of the latest from Isaac Arthur called "Portable Power": https://www.youtube.com/watch?v=ffXqcf48D9Q https://www.youtube.com/watch?v=ffXqcf48D9Q That's not about electric power per se, but maybe a nice context/background. If nothing else, in the first 2 minutes I learned something that I (who studied physics) hadn't even considered: that the electrical words "battery" and "charge" come from artillery terminology!