First all-electric seaplane takes flight in B.C.
cbc.ca
cbc.ca
Going from this DHC-2 to the A380 requires an increase in energy storage by a factor of around 14 000x, while the max takeoff weight ratio between the two planes is only 250.
Airbus is developing a hybrid electric jet, the E-Fan X. They've done the math. When their CTO was asked about the possibility of an all-electric A320, the response was
"""
Assuming for a moment that we’d be able to rely on batteries 30 times as energy dense as that of today, an A320 would be able to fly with half of its payload for one-fifth of its current range, 500nm max. So, assuming a battery which today does not exist... It doesn’t work, purely electrical will not work.
"""
Assuming you mean turbofan vs. turboprop here, since both of these are turbine-driven.
In either case, my understanding is that turboprops don't present a substantial gain in efficiency, as turbofans allow for higher and faster cruising altitude, which reduces drag on the airframe.
Like High speed rail
If we could make progress targeting just short hops targeted by DASH-8s or CRJs or whatever, we could still make significant progress, even if it meant leaving the longer-haul flights alone, or targeting their emissions with different technologies (synthetic fuels from carbon capture, maybe).
It's pretty much a smooth curve, with the breakeven point depending primarily on energy density of your batteries. Until very recently, the electric aircraft weren't possible at all. We're now at the point where two seat trainers with short (but long enough for a typical lesson) endurance are possible and in production. If you look at where battery tech is going, we can probably push that up to 8ish seats and a somewhat longer endurance within a few decades. When you look at the size of even a small regional jet, it doesn't seem likely that current battery tech is ever going to get us to the energy density necessary to make it work.
Not even that. I believe an 86 nmi range is what they are hoping to achieve by 2025. Current range is a fraction of that. The technology demonstrator has a theoretical flight time of 15 minutes and no ability to carry passengers because all the room/weight is taken up by batteries.
And then the other much harder problem which is achieving sufficient Wh per kg energy density in batteries, and Wh per litre of volume. For which they are dependent on global factors for r&d of batteries and improvement in density.
There's plenty of room for passengers in this concept. Where are you getting this false information?
From the article:
> What certainly hasn’t been done before is to fill a Beaver’s cabin with lithium-ion batteries, taking the plane to its gross weight. As a technology demonstrator, this eBeaver isn’t carrying passengers — there isn’t room — and will only have a 15-minute endurance with a 25-minute reserve.
> These are batteries that NASA is using, but they’re not batteries that we’d use if we were going to try and make it economical to fly today, because they’re very low in watt-hours per kilogram
-- "Skunk Works" by Ben RichThe round trip efficiency would be similar to diesel (since you are re-smelting rather than recharging), but the effective energy density on the plane could actually be much better than jet fuel.
I actually think the future may be a lot more simple than we're making it out to be. With some slight modifications to design, we could run existing turbofans on liquid hydrogen fuel. The biggest objection that most people have is the storage of hydrogen...but liquid hydrogen doesn't actually need to be stored in cryo tanks as long as the fuel is being used at faster rates than it evaporates. That's not a problem with jet engine consumption rates...low tech insulation may be sufficient.
Electrical motors would solve this; if we'd be able to avoid dispersing water from fuel cells up high, that could work.
LH2 has storage - and safety - issues still not solved. Toyota Mirai approaches it from a different angle, with some other shortcomings.
1. DHC-2 takes 6 people 86 miles ~= 500person/miles
2. 747 potential battery payload ~= 200,000kg (fuel capacity)
3. Power capacity of 200,000kg lithium-in ~= 25MW hours
4. Power required to take off, assuming 2.5 minutes to reach cruising altitude ~= 90MW * 2.5 / 60 ~= 4MWh
5. Power to cruise at about 600mph ~= 1/4 power to take off = 22MW (waves hand)
6. Time available to cruise ~= 1hr
7. Distance cruised ~= 600miles
8. Electric 747 takes 600 people 600 miles = 360,000person/miles
Maybe the power to cruise is 1/2 of power to take off, they'd still get 120,000person/miles.
Also, the weight on landing is critical not on takeoff, and you can't exactly shed battery weight because empty batteries weigh roughly the same as full ones do, so you will need to take maximum landing weight into account.
Finally, you need to take reserve fuel into account, alternates and headwinds.
I think you should re-do these numbers with more realistic inputs.
Fuel is a major expense for commercial airlines, they don't burn it just for shits and giggles. Airplanes use fuel when landing because destroyed aircraft and piles of corpses will quickly cost more than any fuel they'd save by trying to glide every plane to the ground.
They rely on the plane being lighter from fuel burn and therefore more efficient to extend their possible flight time, but not for safety.
Needing to land before getting under weight usually means a crash landing. In modern times, very few things like fire or an engine self-destructing will require immediately getting out of the air. It is usually better to fly in a straight line, figure out what is going on, figure out where to land, then land. This lets you get underweight, lets you communicate with air traffic control, lets emergency services prepare, etc.
Airliners will dump fuel or keep flying to get below maximum landing weight if possible. If they're still overweight and manage to land without issue, the plane will need to be inspected and repaired before it can fly again.
Contained vapor creates an explosion, while liquid must evaporate first.
Scaling up an electric motor is not particularly hard. Some of the largest machines in existence are electric.
Power is not a challenge for electric. In fact, this electrified seaplane has much more power (560kW) than the original radial piston engine one (336kW), and even more than the turboprop conversion (510kW).
A LOT of very confident people on the Internet post lots of very wrong and/or outdated misinformation about electric aircraft (and electric vehicles in general).
Energy is a challenge, but the answer there is to increase efficiency and increase the mass of the vehicle which is battery. Both of those together give you a usable range of about 1000km. The same motor provider, Magnix, is also providing the motors for the 1000km range Eviation Alice.
Just because a conventional aircraft maker thinks something isn't possible, doesn't mean someone can't make it work. It most certainly doesn't require 30 times the energy density. For the same exact reason why electric cars don't require batteries with 30 times the energy density to compete with gasoline cars.
But if you want to go as fast as a chemical engine and sustain that for as long as a chemical engine, you either need at least the energy density of a chemical fuel or some way to refuel in-flight.
Fuel efficient often means “slow”. Great for cargo, not so much for passengers.
Edit:
Just to add, I’m looking forward to a future of short-range electric personal aircraft, I’m just not expecting pure electric intercontinental for anyone other than hobbyists — unless there’s a big breakthrough in density or wireless power transmission.
Fuel efficient for aircraft doesn't necessarily mean slow, however (unlike ships). What matters is cruise lift to drag ratio. As long as you can adjust cruise altitude for peak efficiency and as long as all the flow is fully subsonic, then lift to drag ratio is mostly independent of speed (as you can increase altitude where the air is thinner to compensate).
So yeah, electric aircraft might stay at Mach 0.5 or so, but they don't need to be slow. Mach 0.5 is still much faster than any passenger high speed rail service and MUCH faster than car or bus or boat.
Pure electric intercontinental may be feasible for near-term chemistries like lithium-sulfur if you continue to push efficiencies (both structural and aerodynamic). Very long haul, like LA to Tokyo, will need lithium-air technology which is a few decades off.
You say "just increase mass of the vehicle which is battery". If you read about this airplane you find that since they are using batteries with an appropriate safety rating for aviation, they've used all the space and mass already:
"this eBeaver isn’t carrying passengers — there isn’t room — and will only have a 15-minute endurance with a 25-minute reserve."
https://www.skiesmag.com/news/harbour-air-makes-history-with...
I tried finding concrete info about the Eviation Alice, but the best I could find was a photo of an unpowered full-scale model. They've been saying the first flight test is a couple of months away for more than one year it seems.
>> the plane’s four-bladed Hartzell composite propeller generated all of the remarkably quiet takeoff sound — a fraction of the thunder from the legacy Beaver’s radial piston
Maybe they’ll get a special class to be able to launch closer to cities without the noise complaints. Although I’d imagine it’s still pretty loud.
Also the bit after the paragraph about the batteries filling up the back mentions they didn’t use fully efficient batteries... they purposefully chose very safe but underpowered batteries previously used and flight tested by NASA for their own testing purposes instead of the higher end batteries used today in EV cars.
And small general aviation aircraft like these usually only have a small portion of their takeoff weight as fuel, maybe 20-25%. But passenger aircraft may have 50% of their takeoff weight be fuel (for instance, 777 on long haul flights). Electric aircraft like Eviation will need to go further (55%). This is something you can do with a cleansheet design like Alice, but can't with a mere conversion designed literally over 70 years with manufacturing and materials from 70 years ago.
And you can apply the same principle of increasing take-off weight fraction for kerosene-powered aircraft as well. The Virgin GlobalFlyer was 82% fuel on takeoff. It flew around the world and then some. Kerosene is much better than it needs to be to enable modern flight.
You're absolutely right about Alice being late, but the design concept is a good example of what is possible. You combine state of the art but existing lithium ion chemistry (which needs some work for aviation certification but IS used on the ground already) with state of the art lift to drag ratio (and perhaps additional innovations, like wingtip propulsion to reduce losses from wingtip vortices) with efficient enough structural mass to enable 55% of the takeoff weight (as well as landing weight, of course) to be battery.
These things multiply together to enable long range.
I don't think you're right from an engineering point of view. Just multiply the aircraft size and battery number by some amount. For example:
>In September 2017, U.K. budget carrier EasyJet announced it was developing with Wright Electric an electric 180-seater aircraft to be developed by 2027. https://www.nextbigfuture.com/2018/09/easyjet-and-wright-ele...
Though all battery aircraft whether micro drones or A380 size will have a limited time they can stay up. Electrics currently seem limited to an hour or so whereas jets can do 16 hours now.
There seems quite a lot of potential on short routes <300 miles though using present batteries. (eg. London Paris or LA San Diego).
With airplanes, you have to lift that weight using the same energy stored within. In that case, energy density is the absolute issue. Nothing else matters.
There's no magical solution, a high-school physics class will teach you how to calculate the potential energy requirement to lift up a certain amount of weight, and dividing by energy density and volume of current battery tech does not lead to a working jet any time soon.
E=mgh
E=(1kg * 9.81m/s^2 * 10.000m) / 3600s = 27.25Wh.
Tesla currently is at around 260Wh/kg thus roughly ten times the amount of potential energy needed to get to 10.000m altitude.
I'd assume that till 2030 we get to ~500Wh/kg by improving current technology. And maybe some quantum leap to 1500-2000Wh/kg within 20 years.
An A320 or A380 will likely always need a fuel cell but a 15 seater with 1000km range is only a question of time.
That's the energy - assuming 100% efficient conversion of battery power to altitude - to lift _only_ the battery to altitude (and then immediately fall back down).
Actual engines are nowhere near that efficient and you'll presumably want to lift the rest of the airplane too. Then you have to keep using power to keep the plane aloft and land it safely.
Your hypothetical 2000Wh/kg future batteries still have a specific energy less than 1/5 that of aviation fuel (Jet A = 11950Wh / kg). A 15-seater electric with 1000km range based on those magic (7.5x better than state-of-the-art) batteries would instantly upgrade to a 5000km range if you tore out the batteries and replaced them with a gas tank of equal weight.
Batteries need a ~40x improvement in their specific energy density to make sense as an energy source for aircraft that depend on thrust for lift.
Tragically, physics doesn't care that battery powered planes would be cool.
I don't know how I can say "no" strongly enough.
If you only need 500km of range, it does not matter a single bit that jet fuel would increase your range from 1000km to 5000km. (Or 100km/180km/5000km respectively, if you want to talk about more contemporary batteries.)
Two things matter. Is the range good enough? How much does it cost? Jet fuel should not even be considered when answering the first question.
Drag increases the square of the velocity. That means going at 500knots (as an airliner does) uses a lot more power than going at the 150knots this seaplane might fly at.
You can calculate an approximate power requirement for the aircraft based on its glide ratio [1] or look at the power based on engine thrust [2]. In all cases you get figures in the 14-80MW range (engines don't tend to be full throttle during cruise)
That means your 260Wh/kg battery would need to weigh somewhere between 54 and 308 tonnes to sustain an hour of flight. That doesn't include takeoff, which is only a few minutes but might reach towards 200MW.
For reference, the 737 (low end power calculation) max takeoff weight is 62 tons and the 747-400 max takeoff weight is 397 tons. So in both cases you're looking at basically 30 minutes of useful cruise with current battery tech.
The range loss is additionally confounded by the fact that current aircraft lose fuel, so lose weight, during the flight. This accounts for a not-insignificant portion of the range.
[1]: http://large.stanford.edu/courses/2013/ph240/eller1/ [2]: https://aviation.stackexchange.com/questions/19569/how-many-...
So basically for electric passenger aircraft with even remotely comparable performance, we need a battery revolution. It definitely won't be by 2030.
We already have a fantastic dense energy battery called kerosene. All we need to do is make it carbon neutral and our existing aviation tech won't even need to change.
If it's nearly suitable for cars I suspect it's even more nearly suitable for aviation on account of the lower volumes and higher margins.
Almost there https://en.wikipedia.org/wiki/Wood_gas
"Flight attendants will resume service in just a moment, after they throw another tree trunk into the wood gas generator"
[1]: https://www.alaskaair.com/content/about-us/sustainability-re...
I.e. burning coal.
(The only reason the industrial revolution switched to coal was because the landscape was denuded of trees. The Jamestown colony in America was tasked with making glass, glass needs lots of fuel, and England ran out of trees. "Connections" by James Burke)
I highly recommend a visit to Plimouth Plantation to anyone interested in 1700's era technology: https://www.plimoth.org/
Or Old Sturbridge Village for 1800's era technology: https://www.osv.org/
The total amount of carbon in circulation is what matters because that part can end up in the atmosphere as carbon dioxide where it shows its heat capturing effects. Trees fix carbon while growing and emit it while decomposing but do not change the total amount of carbon in circulation in the long term.
Digging up carbon that has been locked away for aeons is what is so damaging. There would be nothing bad about burning oil IF that oil were produced by capturing carbon dioxide. We do not do that. We dig up loads of fossil resources and add them to the cycle.
If that explanation was too complicted, here is an easier one: fill a bucket to the brim with water, take a cup and start scooping and pouring back to the bucket. Everything is fine. Now get a second bucket full of water and start pouring into the first (material so far not in circulation is added to it). You see the problem?
If you still insist on your view with burning coal and trees being equivalent, then I challenge you to conduct the water-bucket experiment in the middle of your living room. I mean it wouldn't do no harm, right?
1. chopping down a tree and burning it
2. digging up a tree and burning it
Both are the same. Calling (1) "green energy" is outright wrong. Want to be green? Burn less carbon. The source of the carbon you're burning is irrelevant.
Here is a good overview of the plan: https://cleantechnica.com/2019/10/30/no-you-dont-have-to-wor...
Our biology and our biosphere are not adapted to the atmospheric CO2 levels we would have if we burned all the fossil fuels.
Nope. You're emitting exactly the same CO2.
Want to be green? Burn less. Changing your point of view won't lessen CO2 emissions. Burning less carbon will.
It’s also fine to burn fossil fuels if you can make long-term carbon sinks from other processes, hence people caring about making carbon-rich rocks or whether dead plankton floats our sinks.
It’s a question of being responsible for the consequences of actions, not outright banning those actions before the alternatives have been deployed at scale.
Nobody is worrying about CO2 on geological timescales. It is simply not relevant to any discussion anyone is having, or any problem anyone is trying to solve.
This isn't complicated? How are you managing to miss the point with such vigour?
I could ask the same of you - how are you helping matters at all by chopping down a tree and burning it over digging up a tree and burning it? You're emitting the same amount of CO2.
Want to reduce global warming?
1. plant a tree
2. burn less
If you're wondering what to do with the tree after it grows, you can:
1. use it for lumber
2. bury it
Neither makes the situation BETTER. But one makes it WORSE.
The difference is in the timeframes for capture and replacement - with coal it is millions of years, and with wood it is years. That means burning coal releases carbon which was trapped millions of years ago, and it would take millions of years to trap equivalent amounts of carbon with the formation of new replacement coal deposits. Burning wood on the other hand releases carbon that has been trapped within our lifetime, and it is easy to replace with new trees grown in our lifetime. Bear in mind that if we reverse millions of years of carbon capture we would revert the atmosphere to what it was like millions of years ago, and time travellers visiting that era are likely to need breathing equipment.
I believe his exact quote was:
""" Sometimes I get criticism for, ‘why are you using combustion in rockets and you have electric cars’. There isn’t some way to make an electric rocket. I wish there was. But in the long-term, you can use solar power to extract CO2 from the atmosphere, combine it with water, and produce fuel and oxygen for the rocket. """
That Musk is no Tom Swift. Tom even had an electric rifle, not just a flamethrower.
which he used to great advantage in colonizing Africa
Except making it carbon neutral will require enormous amounts of energy, shift the price up, and make aviation available only to the richest among us.
Aviation industry may keep existing, but will need to scale down.
Also, we have a huge amount of free nuclear energy, daily delivered from Sun, about 1 kW / m². It is nit stable enough for electric baseload, but, depending on the process, may be adequate for fuel synthesis.
North of Sahara may become a primary source of jet fuel, given its vast amounts of insolation, cheapness of the land, and access to seawater. Not exactly tomorrow, though.
Anyways, this is the way France is going.
Another topic of research is very rapid sub-orbital passenger flight. Are there any numbers on proposed fuel efficiency for that? I'd expect you gain a lot by removing hours and hours of wind resistance, but getting up to speed and out of the atmosphere probably (gut feel) uses more.
A step in the right direction, but I hope this doesn't get used as an excuse to fly more.
I just read your message as, “Can’t be done yet, will most likely be done somehow in the near future”.
Scaling up on range is different, but just scaling size/passenger count I would think would be easier.
What electrical flight will do initially is enable the 5$ hamburger flight and create that market. Same distance, same speed, fraction of the cost. GA is currently prohibitively expensive mainly because of fuel. Operating that kind of flights commercially offers similar advantages though you still have to account for the pilots.
And while pilot cost is a factor, their availability is a much bigger problem. There simply aren't enough of them to operate the tens of thousands of mass produced electrical planes that on paper could out compete commuter jets on cost, scale, noise, flexibility, ability to land just about anywhere, etc.
The solution to that is self flying planes, aka. drones. This will likely happen long before we train up hundreds of thousands of new pilots. Like self driving cars there are challenges for this and like self driving cars those challenges are increasingly of a legal rather than a technical nature. It's technically feasible but getting permission to actually start doing this will take time and is happening very slowly despite e.g. Waymo 'drivers' actually needing to touch their controls is now becoming a once every few tens of thousands of miles kind of thing.
The list price for the Eviation Alice (projected to hit the market in 3-5 years) is around 3M and flies 9 passengers. The list price for an A319 is around 90M and flies about up to 160 passengers. So, ballpark it's not unthinkable to fly similar amounts of people using 20-30 mass produced self flying electrical planes competing on most 1-2 hour hops that these jets are typically used for. That will take decades to happen but it is entirely feasible with today's level of technology.
Small planes are not fundamentally hard. Cessna nailed mass production decades ago and electrical planes are vastly simpler (way less moving or combustible parts) And as Tesla and other battery manufacturers are showing, there's nothing fundamentally hard about producing a few hundred kwh of battery at a reasonable weight. A small plane with 500-1000khwh of battery will have a very usable range. With increasing energy densities, that will eventually extend into longer ranges as well. The Eviation Alice manages close to 600 miles on 900 kwh of what is essentially similar to the current energy density of mass produced EVs i.e. hardly the state of the art in battery tech. They are holding back here to get this thing certified ASAP instead of opting for already existing newer battery tech.
The impressive thing about this particular announcement is that it is a cost effective conversion for planes that are 60+ years old with a very well understood mission, which is very short hops. The reason that is economical is because combustion engine economics for that are so spectacularly bad and always have been. Electric flight is going to kill that market first and very soon because it hardly was a market to begin with. Small electrical planes crossing the Atlantic is going to happen at some point in the next decade or so. From there to that becoming a routine thing will take more time. But once that happens, it's likely to challenge the economics of dong the same in a 747. There's no fundamental need to scale electrical planes to that size even though that will probably eventually actually happen as well; but that will indeed require decades of improvements in energy density in batteries.
The only questions around electrical flight is when, not if.
First of all: citation needed.
Secondly: it's a disengenious argument to say "you can't scale it up", then give the largest passenger aircraft in operation as your first scale up target.
What about scaling up to the size of the propellor aircraft regularly carrying people between Amsterdam and many cities in the United Kingdom every day, or thousands of the other short haul routes? Indonesia is another example.
[0] https://en.wikipedia.org/wiki/Airship
[1] https://www.sciencealert.com/this-gigantic-chinese-airship-f...
I think hybrid would be a great compromise. Short range jets spend a lot of kerosene just during taxi and takeoff. If you could just do launch and climb on batteries and then replenish the batteries from a jet powered generator during cruise, that would already be huge in terms of not just CO2 but also ops cost.
No, it's not going to compete with jet airliners even in the remotely near future. High-bypass turbofan engines have enormous cost advantages over traditional piston engines. It's almost always more economical to use a turbofan engine to power aircraft in anything more than a short hop.
I see this being a classic case of something like Mainframes vs. PCs however. Most people don't equate flying with General Aviation because GA has traditionally been so cost prohibitive, much the same way that mainframes were so cost prohibitive in the 60's and 70's. There are a few airlines, like Harbour Air, and Mokulele, that currently offer a short haul flights (usually over water) where people are willing to pay a lot more money. There are benefits like frequency of flights, but the big ones for me are not having to queue up for security, and being able to bring liquids on board. My wife once brought a can of soup on board Mokulele. Try doing that on Hawaiian.
If this can bring down the cost of short haul flights, particularly those around 200-250 miles, it could be extremely appealing, especially when coupled with ride hailing. I would much rather take a 45 minute flight and get Lyft on the other side, than spend 3 hours sitting in a car stuck in traffic. GA can fly out of smaller terminals and smaller airports. San Carlos (SQL) to South Lake Tahoe is a 40ish minute flight in a GA aircraft, but can be 5+ hours in traffic on I-80.
So while electric is a long way from long haul domestic routes, let alone international, I could see it taking over specific services like this fairly quickly, at least relatively speaking. I can see why they are experimenting with it.
Apparently they plan to have certification for this aircraft in the next 2 years, but early days yet.
[0] https://www.pressandjournal.co.uk/fp/news/islands/1893676/el...
> "It's a prototype for sure," said McDougall, "but in every way it's a high-tech piece of equipment, which is kind of ironic considering the airframe that it's attached to is actually one year younger than me — 62 years old."
> McDougall's flight is the first exercise in what is expected to be a two-year process to get the e-plane certified for commercial use.
For some context Harbour Air is a scheduled floatplane airline operating primarily between Vancouver and Victoria in BC. Since there is no bridge connecting the capital Victoria to the largest city Vancouver, they offer short flights on seaplanes that connect downtown to downtown as an alternative to ferries or larger airplanes that arrive at the airports further outside of the downtown core of either city.
In this constrained context it seems like an electric airplane could work really well and provide fuel savings and a quieter ride. They also seem to have some ambition with these electric aircraft to provide other short range flights.
> MagniX CEO Roei Ganzarski said Dec. 10, 2019, will go down in history as the start of the electric aviation age, and believes the e-plane will eventually revolutionize how people travel by making short- to mid-range flights more economical than driving. "It means you can stop driving for three, five, seven hours to get to a destination because there's no other way to get there," he said. "It means you can fly in a small aircraft from a small airport to a small airport.... It's faster, cheaper and more convenient than any other method of travel, including going with a standard airline."
https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...
Edit: just happy to see it get traction.
Fuel is quite pricey here, they might end up saving a couple hundred dollars per hour in fuel and engine upkeep costs.
Making a bridge would be incredibly expensive and be a lot of firsts in bridge making, so it's not worth it: https://www2.gov.bc.ca/gov/content/transportation/transporta...
When I lived in the northwest, it was trivial to drive+ferry to Victoria, even though it was very slow. I always thought the Clipper hydrofoil, let alone flying, were unfathomably expensive luxuries.
But as a tourist without a car and on a limited schedule, suddenly the Clipper (hydrofoil passenger-only ferry from downtown) and flying seem like reasonable options versus having to rent a car, pay for fuel, take a car ferry, drive a bunch on both ends, pay for parking, etc.
In the end, I think Kenmore cost less than 2x what the Clipper would have cost us. Not cheap, but absolutely worth it for a novel one-time experience. One passenger even remarked that the seaplane flight was cheaper than flying from Sea-Tac to Victoria airport, before even factoring in the fact that neither airport is near the major city you're coming from or going to.
Fuel cells might be viable too and the regulated commercial nature of planes probably means that hydrogen's storage and pumping headaches wouldn't suffer the consumer problems.
But biofuels are probably the way to go for now.
There are probably hybrid airship designs with solar panels that could do lower cost shipping. All that extra surface area from the blimp can be covered in solar panels or those fancy solar paints.
200mph at altitude... well, with the jetstream it seems.
Also, could electromag catapults help with takeoff?
Super neat project, although I agree with other commenters that "fully-electric commercial flight" is misleading.
If I walk down there and book a flight, I'm not going to be in an e-plane. It's still very much experimental.
With all that, the range is 15 minutes, with a 25 minute reserve. That is not even enough to reach Nanaimo, which is the closest town the planes could potentially serve.
So, neat demonstrator but a long, long way off from viable commercial operation.
Additionally, they are using bulletproof flight-certified batteries which are much lower than the typical good lithium ion batteries used in, say, a Tesla. They're just for the prototype. "“These are batteries that NASA is using, but they’re not batteries that we’d use if we were going to try and make it economical to fly today, because they’re very low in watt-hours per kilogram,” explained McDougall."
The electric motor (not an engine) is 560kW, almost twice the original 336kW radial motor, so it's not in the least underpowered (as you imply).
(Hints of sarcasm, but some truth there too)
Free power?
Let’s assume west coast flights don’t apply, only ones in the SE United States. Even then, you could maybe be “lucky” enough to get one strike per day.
Doing some very rough napkin math, a lightning bolt can provide ten billion watts of power, but for something way less than a millisecond (most sources I’ve seen say closer to a nanosecond, but let’s be optimistic and go with 1/1000th). Assume we have the ability to buffer this (we don’t, to my knowledge), that gives us 10MW for one second assuming 100% efficiency. A 747 takes 90MW of power just to get airborne and it needs that for longer than a second even for that. So basically you’d need something like at least 100 lightning strikes just to get the 747 airborne (assuming that’s doable in 11ish seconds, I think it “might” in extreme circumstances).
I’m sure my math is grossly flawed in some way, so don’t expect scientific accuracy at all, but it should clearly show the absurdity of using lightning as a power source for jet flight.
Yes a single lightning strike contains roughly a similar order of magnitude of energy as an entire charged flight battery would but it is delivered in microseconds. That comes out to hundreds of terawatts of power while in comparison the new Tesla supercharger charges at an incredibly high rate of hundreds of kW. That's 1 Million times lower than lightning! There is no substance on earth that can absorb and store energy at that power rating.
On top of all of that, even if you could get it to work it would be such an unreliable source of energy that it would never make any economical sense to deploy on plane if you could just capture it on the ground and charge the plane from there.
About a decade ago an astrophysicist friend of mine told me that you can store lightning energy into some kind of a supraconductor, the problem being that we don't know how to take the energy out.
I believe he described something similar to [Superconducting magnetic energy storage](https://en.m.wikipedia.org/wiki/Superconducting_magnetic_ene...)
The internet says the energy of a cloud to earth lightning strike is 10^9 joules. A gallon of jet fuel contains about 10^8 joules of energy. A strike would provide the equivalent of 10 gallons of fuel.
A 737 would need to be struck at least once every 10 miles to keep going.
Sadly, that lightning power number is for cloud to earth, a cloud to airplane is going to be far less. If you try to extract too much power from the bolt it will just go around you.
␄
Meta comment: I like the breadth of this comment's peers. We have this one about the scale of energy, one commenting that it doesn't help range because you can't rely on it, one about the disparity of power between charging and discharging, and one about avoiding complexity and mass in airplanes. All good points. I hope in 12 months we hear back from the lunatic that ignores them and makes a functioning prototype.
That said I wonder if helium filled balloons with extremely capacitors could absorb some of the voltage difference in the atmosphere and act as mini batteries.
Some people already tap into atmospheric voltage near ground with drones carrying long wires.
A single GE90 aircraft jet engine used in the 777 is up to 111,000 horsepower[0]. So for the Boeing 777, that’s ~220,000HP. Converting horsepower to megawatts, that’s 164MW of power during takeoff (and approximately half that during flight). There’s approximately 500-1000 B777s (very rough, but educated guess) in the air at any given moment during the day. That’s 82.5 gigawatts of power just for the 777 flights alone, not counting all the other commercial aircraft in use.
So how much is 82.5GW?
> The Palo Verde nuclear power plant in Arizona is the largest nuclear power plant in the United states with three reactors and a total electricity generating capacity1 of about 3,937 MW.
So 40+ of the largest nuclear power plants in the US?
> average wind turbines produce 1.5MW of power at 100% efficiency
So 55,000 wind turbines at minimum? Better hope it’s windy!
Flipping it another way:
> an average LCD TV uses 200W of power
So in other words, turn off 400M TVs around the globe to offset the power needs of up to just 1,000 planes.
Now finally...
ignoring the electricity generation needs, let’s talk about just battery storage on the plane itself. A typical 18650 (the battery that is commonly used to make large cells, for example in your electric cars) is something like 9W of power. So you’d need something like almost 20,000,000 batteries just for a short flight. Each 18650 weighs about 45g (not including wiring harnesses and safety gear). That’s 200,000 pounds of batteries. The batteries alone for a short flight is multiples of the weight needed in fuel for an international flight.
[0] https://www.bangaloreaviation.com/2009/10/worlds-largest-air...
[1]: https://www.nrk.no/sorlandet/elfly-med-avinor-sjefen-som-pil... [2]: https://translate.google.com/translate?sl=auto&tl=en&u=https...
https://particle.scitech.org.au/tech/aussie-first-electric-p...
An electric motor may have a longer service life than an engine, and is almost certainly much less expensive to service.
No, it's not. A propellor creates thrust by slicing the air and creating lift just like a wing, but in a forward direction. A jet engine's fan blades create no thrust in themselves. They provide the compression needed for combustion to occur within the engine, and thrust is created by the expelling of hot exhaust gasses.
This is done to trade the high speed of the jet exhaust for a larger amount of air moving more slowly. Making the speed of the jet plume closer to the true airspeed of the aircraft makes it more efficient.
Looking at design of turbines, a lot of air is needed above the amount for combustion to help keep the post combustion chamber turbine from melting (or just weakening to the point of failure). Some of this will be the unburnt (nitrogen, etc) components of the ingested air but a lot of design goes into moving air around components to move heat away from them.
The less air needs to be compressed for the engine then the more efficiently it will run. This is often achieved by designing one that can run hotter. This is also one of the other ideas behind having the bypass on a turbofan, reducing the amount of air that is compressed.
I know people call Jet-powered aircraft "jets" but, that's really an abbreviation.
I think what you're asking though, is whether there are any electric propulsion systems with the same characteristics as jets - i.e. more thrust relative to speed. AFAIK, there are not, because a characteristic of chemical fuels is that increased compression and airflow can increase the efficiency of the reaction. Electric motors have a (relatively) fixed efficiency due to the battery.
The propulsion of a 'jet engine' is normally through a gas turbine, which is a type of internal combustion engine, so you wouldn't get an electric gas turbine.
Replacing the gas turbine with an electric motor would in this case produce an electric jet engine.
Electric will never replace long haul jets barring a revolutionary breakthrough in battery technology. But that's not the point. Much of commercial aviation takes place on distances of around 100 to 500 miles. That is, too far to drive but not quite far enough to take advantage of the efficiency of jet engines at high speed, high altitude cruise. For those applications electric propellor and ducted fan aircraft will be absolutely game changing. It will make these flights cheaper and safer by a factor of 10 at least. The vast majority of cost in a flight is maintenance of the engine. That all goes away with electric power. It will make commuter flights an affordable daily reality for normal people.
Currently increasing fan sizes are getting problematic. That is the problem with the 737 MAX. The fan diameter of the new engines is too large to fit between the bottom of the wing and the ground. So it had to be mounted forward and up which fucked up the aerodynamics.
Two other advantages are, potentially maintaining thrust in an engine out situation. When you lose an engine not only do you lose half your power but the thrust is unbalanced. And faster throttle response. Turbine lag is a big issue with jetliners.
Note: The reasoning behind high bypass turbofans is thrust is proportional to delta v times the mass flow rate. Where power input is proportional to delta v squared. Bigger the fan the more efficient you are and the less fuel you use.
Diesel is kinda interesting. Manufactures are developing diesel engines for light aviation. I suppose you could have a hybrid diesel/electric aircraft.
https://www.tudelft.nl/en/2019/lr/delft-student-team-takes-t...
This is not a commercial flight, currently the plane in question is licensed by the FAA as "experimental" specifically excluding commercial flights.
Still cool! I think electric might have a great future in short-hop flights.
https://www.faa.gov/aircraft/air_cert/international/bilatera...