i just got back from a week in bali. we rent a mini ev 2 person car to get around and in the span for the whole trip we literally spend $0 because we charge them off the wall plug of the villa we stay at
but if we want to be pedantic the car is Wuling airev and iirc it has 17 kwh of battery. that is quite enough for us for the whole week, we only need to charge it once at 60%. so lets say its around 7 kwh. in Indonesia a kwh cost around $0.1. so for a whole week it only need less than a dollar for ‘gas’
Is there no simple anymore? Plane A went this far on 5 dollars electricity. Plane B went the same distance on X dollars worth of jet fuel. I want to know the distance travelled and I want to know what “X” is.
$5 for 30 minutes in the air. pick any speed you want. it doesn’t matter. avgas and jet fuel don’t compete with $5.
$3.60 for mogas at a couple places near me. Very high density altitude, well leaned out, in slow flight, you could get 27 minutes out of a 150 for $5
These guys are also apparently getting electricity for 2-4 cents per KWh, which is many times cheaper than most would be able to get it
You’d even have more useful load than this “jet” that can carry no passengers or cargo
You could also fly a glider. It’d be as useful as this thing
Wrong thread buddy. Maybe you need a refresher in navigation theory.
The site for the plane manufacturers says they have a max range of 125 miles.
So this is practically useless for flights. It’s faster to just drive 125 miles in an EV.
This seemed intuitively wrong to me (like, way too low a cost), but: 25,000 pounds moving 100 mph is equal to 11,331,007 J of kinetic energy. Since 3.6 million J equals 1 kWh and 1 kWh on average costs $0.17, that means you could accelerate 25,000 pounds to reasonable bare minimum flying speed for about fifty cents (not considering efficiency of the machinery). My mind still can’t process this, but math is math.
On the other hand, looking at it from a potential energy perspective it’s a bit more expensive. 25,000 pounds at a cruising altitude of 10,000 ft. (still quite low from an airliner perspective) is about 339 million J, 94 kWh or about $16 – the cost of lunch at MacDonald’s.
Since a plane requires the most thrust at takeoff, you could use ground-based catapults to get the plane to takeoff speed (or faster even) and then you could carry smaller batteries and propelling machinery. For extra fun, you could have landing planes snag a wire and use their momentum to accelerate a plane taking off.
To save even more weight, since you’re going airport-to-airport you could leave off the landing gear and just have the planes come down on a bouncy trampoline-like surface. If you think that’s batshit crazy, the British actually experimented with this idea for their aircraft carriers in the 1950s.
Edit: to make these numbers more realistic I’m going to assume something like a 737, which can weigh something like 150,000 pounds fully loaded (this includes fuel but you’d need batteries instead for an electric plane). Getting this to a 150 mph takeoff speed would take about 100 million J (getting it then to a cruising speed of 500 mph would be another 233 million J, but that’s pretty minor compared to the other costs). Climbing this plane to 30,000 ft would take 6.1 billion J. Resisting a drag force of 5000 pounds (about what a 737 experiences at cruising speed at 30,000 ft) for 500 miles (the distance from Cleveland to New York City) would need 17.6 billion J. Assuming landing is free (fuck TANSTAAFL) that means a typical trip needs 23.8 billion J or 6618 kWh or $1125. Assuming a real-world efficiency of 25% means the actual cost would be $4500 (which is in the ballpark of what jet fuel costs). Assuming 200 passengers, that’s $22.50 per person. Not exactly “$5 of electricity” but surprisingly small.
Feel free to check my math, my brain hurts.
Since a plane requires the most thrust at takeoff, you could use ground-based catapults to get the plane to takeoff speed (or faster even) and then you could carry smaller batteries and propelling machinery.
Don’t you dare talk about catapulting using electric technologies in America though. Steam only! 🇺🇸🗽🦅🏈
I didn’t say which type of catapult. I don’t need ICE showing up at my door.
There are many who have suggested replacing the fuel intensive takeoff with electric ramps, similar to what the do on aircraft carriers. The problem is most people could not handle 3-4 gs.
But, there could be a detachable battery pack that disconnects after takeoff to fly back to charge as a drone.
One important caveat to this. It costs less than 17 cents to generate 1 kwh. Closer to 3 cents really. But that’s the cost of making the electricity, getting that electricity to a house or charger or what have you costs more. Since energy is a for profit industry they tack all the logistics costs to the client buying the electricity.
So your math is spot on but I fear the amount of markup on the electricity will be massive especially since it’s for a business let alone an airline.
National average it’s 55¢ to run 3kw on 3phase electricity for an hour. Offshore areas like Hawaii and Alaska see higher costs like 1.60$/hr per 3kw on 3phase electricity but Alaska has a higher natural gas usage and Hawaii is further away from the CONUS electrical grid. National average per 24/hrs of charging is a little over 13$ with 3kw at 3phase.
And yet it still costs me 30 dollars to charge my car in Georgia and in a state like new York it’s 60 to 100 dollars.
I fucking hate everyone and would love to subject you fucks to 4g of pain taking off with a stupid catapult system. Nice math.
All those screaming kids would get a quick education on how relatively nice everything was before the plane was launched.
“Billy, why are you crying? Do I have to take you on another plane ride? Oh, you’re gonna cry harder now? That’s it, I’m getting the vomit bags. I got this nice new child design one for you that wraps around your head and ties closed at your neck. Won’t that be a treat?”
The Navy is stupid.
Since a plane requires the most thrust at takeoff, you could use ground-based
Actually dragging (or wheeling in) a wire or having a wire car supplying the plane with electricity during takeoff would work too.
I think the only realistic use case is going to be short trips. For long range offsetting the carbon for jet fuel just makes more sense.
But really small personal vehicles could be interesting. There is the Pivotal BlackFly which can VTOL and uses less electricity than a big electric car - and it needs to roads. So for commuting this could actually work to save on infrastructure.
The biggest problem with flying cars is, well, have you seen how people drive?
It’s stressful enough just crossing the street. But at least you know when you’re doing it, look both ways, look around for idiot drivers. If there were flying cars you’d always be in danger everywhere.
look both ways
Which many don’t regularly do and now added vertical dimension, more directions to look.
Can you imagine the chaos of hundreds of thousands of flying cars all trying to takeoff or land at the same time during morning and afternoon commutes. It would be glorious to witness, minus the human carnage. Even with the help of air traffic controllers there are still collisions with the current volume of air traffic. In a word, unworkable.
Two obvious solutions to traffic congestion in the US are work from home and replacing the public transport networks that automobile and oil interests dismantled.
Yeah and airplane pilots have to do a whole lot of training before they’re trusted with flying.
And yeah, 100% agree on better public transit and more WFH. We’ve developed technology to do this but somehow people insist that we should all sit in moving metal cages surrounded by six lanes of other people in their metal cages every day so we can have a Teams meeting with the person sitting next to us in the office.
Actually dragging (or wheeling in) a wire or having a wire car supplying the plane with electricity during takeoff would work too.
After doing more of the math, I realized that the energetic cost of takeoff is quite a small fraction of the overall cost. So the only real benefit of the catapult would be to reduce the size and weight of the propulsive machinery on the plane. So externally providing just the electricity wouldn’t be much of a benefit.
This is a pretty bananas idea, but I wondered if in the future we’ll be able to have something like a large robot arm “throw” a small plane from the top of a skyscraper as well as catch it for landing. Something like a modified trebuchet, slowly storing energy in a suspended weight to power throwing the plane, or to store the energy from catching the plane. We’d probably need further advances in robotics control, and the arm might need to be too heavy to be fast enough. And overall this makes even less sense than a catapult / puller that is already in use for gliders.
To do that, you would need a short acceleration of 3-4gs. That’s like 900-1200lbs of force on husky Americans l
yeah it’s pretty crazy how much energy is in fuel.
1 kg of oil contains about 30 MJ of energy. enough to accelerate an object of the same mass to 7.7 km/s. which is almost escape velocity on earth (11.2 km/s), or enough velocity to shoot the object out of earth’s gravity field altogether.
(a kg of oil, ofc, costs about $1)
This plane can’t carry passengers. All the useful load is taxen up by batteries. It’s the fundamental issue with all-electric aviation
Well, feel free to correct me on my math here, I’m no battery expert. Google says a 100 kWh battery typically weighs between 1000 and 1500 pounds. Since we’d need 6618 kWh for the hypothetical trip from Cleveland to NYC, that means we’d need 67 x 100 kWh batteries which would weigh between 67,000 and 100,000 pounds. Google also says the typical fuel load for a 737 is around 50,000 pounds, so the relative overage from batteries (since obviously you wouldn’t need to carry any fuel) would be 17,000 to 50,000 pounds. This would roughly give you a passenger capacity range between 120 and nobody. Even worse if you consider the need to have some reserves of power for unexpected circumstances. There’s also the problem mentioned elsewhere in this thread that the batteries don’t become lighter as they’re discharged, so your landing weight is the same as your takeoff weight.
So yeah, battery weight is the core problem. But if battery weight comes down by “just” 50% (and I have no idea if that’s on the horizon or not) then electric aviation becomes quite viable.
There is nothing in labs to even suggest that battery capacity in the next 20 years.
OK, electric planes are fucked then. No wonder they’re resorting to “$5 of electricity” clickbait bullshit.
For extra fun, you could have landing planes snag a wire and use their momentum to accelerate a plane taking off.
What about Flintstones style breaks, where everyone’s legs stick out under the plane and they need to use them to stop?
Sure, it wouldn’t be effective, but one or two of these new flights being on the news and global emissions would be down even farther than with your plan.
I was about to crunch the numbers to check for myself, thanks for doing it, you did a great job.
Amazes me how they made it work considering the amount of arcane shit it takes to make jet engines work. Of course it is possible since electric motors are torque monsters, but it still must’ve taken insane efforts to make it work.
I wonder if we’ll see these flying anytime soon or if they’ll get shot down by the fossil fuel i industry just like everything else that is amazing
It will never practically work unless there is some fundamental new technology to store electrical energy, and the periodic table says no.
Wouldn’t work Militarized though because you wouldn’t be able to refuel it mid flight.
Microwave beams from satellites. What could go wrong?
People down here acting like $5 to keep 25,000 lbs in the air for 30 minutes is not a milestone worth announcing.
“Be perfect NOW” 🤣
Because they didn’t. And anyone that is capable of critical thought can easily take the few numbers they provide in the article and do some simple calculations.
They claim the motors pull more than 1mw of power. So using 1 mw for 30 minutes is 500kWh. That means they paid 1 cent per kWh. (Spoiler. They dont)
And nowhere, does it say the plane weighted 25000 pounds. It says it “can exceed” 25000 pounds. But by no means does that mean that’s what it weighted in this test.
The most likely scenario is that the plane was bare minimum rather than maximum. I doubt even passenger seats were installed.
This plane is a piblicity stunt and will never be a viable product (the company itself said it is not meant for commercial production)
This “jet” has a lower max speed than a Cessna 150, a service ceiling of 2,000 AGL - far less than any commercial aircraft. It weighs 25,000 pounds with no passengers or cargo, almost certainly it’s max weight. They can’t even fit a 2nd pilot
They do not disclose how much energy was actually used, just a vague “$5” figure and a listed max power of 1MW
It’s just a marketing ploy and you fell for it
What you need is a cookie. Cheer up.
In other words the Us won’t use this technology because it hurts the oil companies pockets
Us??
I’m guessing autocorrect swapped “US” with “Us.”
Wow dang. For some reason I was hoping it was a new slag on the uneducated or something like that.
Damn Us are at our again. Someone should stop the US.
Time to pass those savings onto the
consumershareholders!I did my best to find any technical data about the flight. Couldn’t find any actual numbers. FWIW it’s not intended to be a standalone method of powering the aircraft for commercial use; they plan on making it a hybrid, which makes far more sense as far as range and payload are concerned. Best guess a 25000 lb aircraft like this will probably cruise around 120-150Kt at a nice, slow, efficient airspeed for a test like this. So maybe a 40-50 mile flight because “air time” probably started as soon as they lifted off.
Yeah the problem is they also don’t tell us the load during the flight. From the lift equation (let’s be hand wavey) if they’re a similar size to a regional jet (same planform area) your heavy lift is better driven by speed than lifting coefficient. Of course, it’s hard to go fast with electric props, so I wonder if a safe ceiling is probably
400Kt300Kt?Gives a nice range of you know… 40 to
200150 miles.Edit:
No way. The speed record for a prop aircraft currently stands at about 300Kt. If we use that generously our new ceiling is lower.
It’s right there, friend.
25,000lb. Reading the article it says “more than 25,000 lb”.
We should assume they used a highly efficient airfoil that can maintain the most efficient possible cruise for the demonstration aircraft probably at L/D max if they’e looking for time aloft, so I doubt it’s even worth considering top speed or ceiling. It would be interesting to know what NACA profile they used and what the top speed characteristics would be.
Edit: looks like a Vne of 140 Kias. This is not a fast aircraft. Also a minimal useful load. If you make a couple clicks through to the site of the test it’ll give you more info.
The first flight of the largest battery-electric aircraft to take to the skies lasted nearly half an hour while costing just $5 of electricity.
The X1 aircraft is comparable in size to a small regional airliner and can achieve a maximum takeoff weight exceeding 25,000 pounds with the help of four wing-mounted electric motors. The battery-electric propulsion system delivered more than one megawatt of power during the maiden flight.
It doesn’t tell us what the load was for the test flight at this price point.
You’re probably right that it is good and slow and much less weight.
Likely a short flight.
If they can fly a small airliner for 30 minutes for $5. Either there’s a whole lot they’re leaving out. or they’re not paying anywhere near what I pay for electricity.
They say the engines delivered more than 1 megawatt of power. Cool, so 1 MW over 30 minutes. That’s 500kWh. Which means if they paid $5 for it. They paid 1 cent per kWh. Now i don’t know about you guys. But i sure as hell don’t pay 1 cent per kWh.
they’re also dont specify how many kwh they used. which is why i assumed a sustained 1mw of power. they also dont say how much the plane weighted. only what it could potentially carry. that doesn’t mean that’s what it weighted in the test.
don’t get me wrong. cool stuff to fly electric planes. but i can’t help but feel incredibly sceptic when they leave out a lot of numbers while making the insane claim that they only used $5 worth of electricity.
Every time I hear of an all electric aircraft of any size, I always wonder what they’re going to do about landing weight.
Every modern transport category jet has a higher takeoff weight than landing weight, because of the simple unavoidable fact that landings are rougher than takeoffs. Taking off, the load gradually comes off of the landing gear, on landing it’s suddenly applied. Jets burn tons, literally tons, of fuel enroute, so they’re considerably lighter on approach. It’s why aircraft have dump valves to jettison fuel overboard in case of forced landing early in the flight.
Batteries don’t get lighter as they’re discharged, so…?
You can rethink the engineering with electric motors.
The planes you are describing are designed assuming they will be lighter on landing because of fuel. So why design them for take off weight?
Electric motors are condusive of blown wing design for example, and would have a unique landing profile. (The plane can land at much slower velocity)
Edit: yeah they’ve moved the engine shroud which allows for lower speeds. Given the same runway you would be able to trim vertical speed.
That ain’t gonna happen on a civilian airliner.
Blown wings are basically powered lift. You’re planning on bringing a civilian passenger plane down final approach at a speed it can’t glide at if the power plant fails?
I could see that for a carrier based aircraft where STOL is a factor but no you’re not doing that in airline operations.
Why couldn’t it actually be safer since you could have distributed power centers, across multiple motors?
You could also have hybrid approaches - there is space between not being able to glide and smashing your landing.
I’m just getting at it being a different system so some old assumptions can be reexamined.
Bigger challenge than landing is energy density.
Regardless it’s a very interesting space.
Multiple redundant motors are heavy.
Batteries are far heavier. There’s going to be as many motors are there are propellers, it really doesn’t make sense to do otherwise.
You can rethink the engineering with electric motors.
One of the other limitations is that you’re stuck with propellers if you’re using electric motors, so your top speed is going to be significantly slower than jets. Unless you do the Tu-95 thing with contra-rotating props whose tips exceed the speed of sound, and then you have monstrous noise problems.
Fun fact, batteries DO become lighter when they discharge. But obviously not like fuel. But it’s still a fun fact.
You mean because of e=mc²? That’s true but basically unmeasurable. Air batteries do get mesurable heavier.
FYI 1 kg battery when fully discharged loses about 10⁻¹² kg of its rest mass …
That’s ridiculous. No one on final gives a crap about take-off weight. What you need is a ride in a glider or parachute. Learn to land on your ride’s minimal weight. Dropping stuff is only an extra measure if possible, not a necessity.
when r/fuckcars thinks they know anything about aviation.
↑ when a video game pilot thinks they know anything about aviation ↑
I’m a CFI.
Oh boy… So, they took off from a test facility adjacent to Plattsburgh International Airport. I don’t see it stated, but I give it 98% they landed where they took off. Plattsburgh has some of the lowest residential and commercial electricity costs in the country, so that $5 nets them about 110kWh of juice.
They also reached a maximum altitude of 1,100 feet with a plane that weighs in excess of 25,000 pounds. Lifting 25,000 pounds up to 1,100 feet takes 37 million joules of added potential energy, or a bit above 10 kWh.
The entire remaining 100kWh of energy budget is the equivalent of accelerating the 25,000 pound aircraft up to 252 meters/second at perfect efficiency in a vacuum. This flight was not going very high, and it was not going very fast.
If the economics of their hybrid idea work out, it’ll be fantastic, but the attempt at marketing over transparency here doesn’t fill me with optimism.
Thank you for that.
They didnt say the planes weighted 25000 pounds. They said it could exceed 25000 pounds. My guess is that not even the passenger seats were installed in this run.
1mw of power from the 4 engines. For 30 minutes, 500kWh. So for $5 they paid 1 cent per kWh. Somewhere there’s a bunch of bullshit hidden.
I give it 98% they landed where they took off
They did. It can bee seen in the press release photos and the video they released
so that $5 nets them about 110kWh of juice
They would have needed more than that. Likely got some lower rate somehow
This flight was not going very high, and it was not going very fast
Vne, max airspeed, of this plane is 140 knots (72 m/s). Less than a Cessna 150. Max altitude is 2,000 feet AGL, significantly lower than a Cessna 150
If the economics of their hybrid idea work out, it’ll be fantastic
It would be, but I highly doubt it. Energy density of batteries is simply too low. This plane can barely fly at slow speeds with no cargo or passengers, and with a cockpit stripped down to a single pilot. Hybrid thrust would be heavier than either jet A or battery-electric, and it still has the downsides of including batteries for the entire flight
Hydrogen or nuclear will be viable before battery-electric in aviation
Good and as battery technology improves, EV aircraft would be ideal for short commuter hops.
Dude, I’d take short hop flights all the time if they end up being that environmentally friendly.
I can understand a hybrid train because of certain sections of track electrification issues and the fact that diesel electric is how even trains that run entirely on diesel operate so you’re essentially just toting around a generator to operate your already electric engine. I understand hybrid cars with regenerative braking and range extension. I don’t really understand hybrid planes.
Like I can imagine electric is more efficient for takeoff because electric engines produce more initial power generally than what fossil can match per engine size(a big part of both hybrid trains and cars both using batteries for initial acceleration) and then you cruise with jet fuel. I’m just having a hard time imagining it is worth it from a defossil fuel perspective or from a straight efficiency perspective.
What if the worthwhile goal and priority were in fact to “defossil”?
What do you mean? I favor synthetic aviation fuel derived from hydrolysis which is very lossy on energy and would largely kill most current air routes in favor of trains. I think a 40x price increase on fuel is likely, but the actual implementation is proven since it’s essentially plug and play with existing infrastructure. I think the best way to make up for the subsequent loss of profitable air routes is electrified rail. This tech isn’t for getting off oil though, it’s for reducing use at best and if it actually does improve efficiency it would be used along with synthetic fuel.
i also prefer electrified rails, but i’m fine with decarbonizing aviation where rails aren’t feasible. rail construction has thresholds to meet in terms of travel density, frequency, and ground conditions.
I really hope this will catch on for once, it could be a great solution for all those people who insist they have to do domestic flights… (in countries like Germany which aren’t that big comparatively speaking)
