# Fuel economics of battery-powered airplanes **URL:** \ **Category:** Factual Questions\ **Created:** [August 17, 2021, 12:25am UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977 "2021-08-17T00:25:05Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [August 17, 2021, 12:25am UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/1 "2021-08-17T00:25:05Z")
**[United just ordered 100 electric planes](https://robbreport.com/motors/aviation/united-airlines-100-electric-planes-from-swedish-1234625038/).** Although car efficiency is affected by weight, I would think that effect is much higher for planes because of the requirements for lift. I also have the impression that enough batteries to power an airplane, even a small one, even for regional flights, would weigh a metric shit-ton. Also, unlike liquid fuel, when the batteries run low they still weigh the same as when you took off. Is engineering so good now that an electric plane is more fuel-efficient than petroleum? Or is this more of an electricity vs. jet emissions kind of thing? (Also, they refer to them as zero-emission but I think there might be some emissions involved in generating electricity. A debate for another day.) ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [August 17, 2021, 1:23am UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/2 "2021-08-17T01:23:04Z")
Not quite. From the link: > [@](#): > > As part of the investment, the airliner agreed to buy 100 ES-19 electric planes from the company **once their aircrafts meet United’s safety, business and operating requirements.** Bolding mine. That last sentence pretty much says it all. No commitments have been made. This is at best a publicity stunt. There is no ES-19 aircraft. It’s all on paper. From the company’s web site: > [@](#): > > Our major milestones towards certification are to complete a Preliminary Design Review (PDR) in Q3 2022, a Critical Design Review (CDR) in Q3 2023, a first flight in Q4 2024, and a Type Certificate in Q3 2026. Entry into service would follow in Q4 2026. They aren’t even going to have a _preliminary design review_ until 2022, but they plan to have the thing certified and flying by 2026, two years after the flight of the first prototype? This is fantasy talk. As a comparison, the Beech Starship had its preliminary design review in 1979. An 85% prototype flew in 1983, and the first full prototype flew in 1986, and the first production aircraft in 1989, ten years after the design review passed. And the Beech Starship used standard engines, avionics, etc. The company claims a 250 km range, without reserve. That’s going to be less than an hour in the air. Standard VFR reserves are 45 mins, and IFR requires you to be able to fly to an alternate airport plus 30 mins. This plane simply can’t do that. If there is some need to fly people 100 km in VFR conditions and there is a ‘short distance’ waiver that allows them to skirt reserve requirements, maybe this plane could do it. In the meantime, the safe assumption is that this plane will never meet safe airline travel needs. Not without some breakthrough in energy density of batteries. And if we come up with a brand new battery type, it will be a very long time before it would be certified for use in an aircraft. I hate to be a downer about this, as I love new aviation tech. But having been involved in aviation since the 1980’s, I have seen many fanciful aircraft advertised, only to have them hoover up as juch money from investors as possible and then vanish. The only feasible electric aircraft I know of is the Harbour Air electric De Havilland Beaver: > **[Harbour Air flies ‘first’ all-electric commercial aircraft, a DHC-2 Beaver](https://www.flightglobal.com/airlines/harbour-air-flies-first-all-electric-commercial-aircraft-a-dhc-2-beaver/135711.article)** > > A Harbour Air de Havilland DHC-2 Beaver seaplane lifted off the Fraser River near Vancouver on 10 December, marking what the company calls the first flight of the first aircraft powered entirely by an electric system. That plane isn’t feasible because of some new high tech battery, but because the planes are used for inter-island ferrying of extremely short distances. They started with a strong plane that could carry a lot of weight and which lands on water, then gave up most of the payload capacity for batteries because in their use case they don’t need the payload a Beaver can haul. It only flies for 15-30 mins on a typical ferry flight. Note that even though they started with a production aircraft and simply replaced the power system, the plane first flew in 2019 and is still not certified. The company is working with Transport Canada on a certification program. Who knows when it will be complete. ---
**Author:** ![N9IWP](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/n9iwp/32/3154_2.png) [@N9IWP](https://boards.straightdope.com/u/N9IWP)\ **Post date:** [August 17, 2021, 1:27am UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/3 "2021-08-17T01:27:17Z")
Note that United only buys once the planes meet certain requirements, which may not happen. 19 passengers and 250 miles seems ambitious to me. Brian ---
**Author:** ![lobotomyboy63](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lobotomyboy63/32/2900_2.png) [@lobotomyboy63](https://boards.straightdope.com/u/lobotomyboy63)\ **Post date:** [August 17, 2021, 1:59am UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/4 "2021-08-17T01:59:05Z")
The Solar Impulse 2 is an interesting case…the sun charges it. Weighing 5100 lbs means it’s lighter than a Cadillac Escalade. Check out the cruising speed, though: hardly what air travelers would accept. > - **Crew:** 1 > - **Length:** 22.4 m (73 ft 6 in) > - **Wingspan:** 71.9 m (236 ft 0 in) > - **Height:** 6.37 m (20 ft 11 in) > - **Gross weight:** 2,300 kg (5,100 lb) > - **Take-off speed:** 36 km/h (22.4 mph) > - **Wing area:** 17,248 [photovoltaic](https://en.wikipedia.org/wiki/Photovoltaics) [solar cells](https://en.wikipedia.org/wiki/Solar_cell) cover the top of the wings, fuselage and tailplane for a total area of 269.5 m2 (2,901 sq ft) (rated at 66 kW peak) > - **Powerplant:** 4 × [electric motors](https://en.wikipedia.org/wiki/Electric_motor) with 4 x 41 kW⋅h (150 MJ) [lithium-ion batteries](https://en.wikipedia.org/wiki/Lithium-ion_battery) (633 kg or 1,396 lb), providing , 13.0 kW (17.4 hp) each [[32]](https://en.wikipedia.org/wiki/Solar_Impulse#cite_note-Lipsey-32) > - **Propellers:** 4.0 m (13 ft 1 in) diameter > > **Performance** > > - **Maximum speed:** 140 km/h (87 mph, 76 kn) > - **Cruise speed:** 90 km/h (56 mph, 49 kn) 60 km/h (37 mph) at night to save power > - **Service ceiling:** 8,500 m (27,900 ft) with a maximum altitude of 12,000 m (39,000 ft) > **[Solar Impulse | Solar Impulse 2 (HB-SIB)](https://en.wikipedia.org/wiki/Solar_Impulse#Solar_Impulse_2_(HB-SIB))** > > Construction started in 2011 on the second aircraft, known as Solar Impulse 2, which carries the Swiss registration HB-SIB. Completion was initially planned for 2013, with a 25-day circumnavigation of the globe planned for 2014. A structural failure occurred on the aircraft's main spar during static tests in July 2012, leading to delays in the flight testing schedule to allow repairs. Solar Impulse 2's first flight took place at Payerne Air Base on 2 June 2014. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [August 17, 2021, 9:43am UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/5 "2021-08-17T09:43:39Z")
A recent thread on electric airplanes which covers a wide range of the factors. > [@Electric airplanes](https://boards.straightdope.com/t/electric-airplanes/844530): > > NASA is experimenting with an electric airplane, the [X-57 Maxwell](https://www.nasa.gov/specials/X57/index.html). It has several changes that should make it more efficient than just replacing the engines and fuel tanks with electric motors and batteries. They’re taking their time on studying it, making only one change at a time, so it’s going to be a while before they get done. Assuming these experiments all work out the way they expect and adding in other ways to make airplanes lighter (e.g. carbon fiber fuselage and wings), how good of an… ---
**Author:** ![Ruken](https://avatars.discourse-cdn.com/v4/letter/r/f475e1/32.png) [@Ruken](https://boards.straightdope.com/u/Ruken)\ **Post date:** [August 17, 2021, 12:10pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/6 "2021-08-17T12:10:16Z")
> [@CookingWithGas](#): > > Also, unlike liquid fuel, when the batteries run low they still weigh the same as when you took off. It’s not just the batteries. The wiring and power electronics are heavy. You can reduce wire weight with higher voltage, but high- (or maybe it’s considered medium-; this isn’t my area.) -voltage breakers and other electronics for DC circuits are IIRC wanting. You specifically asked about batteries, but more broadly, electric aviation is not restricted to carrying all the “fuel” in batteries. You can generate electricity with a fuel cell or even a turbine using any number of fuels. ---
**Author:** ![ZonexandScout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zonexandscout/32/544_2.png) [@ZonexandScout](https://boards.straightdope.com/u/ZonexandScout)\ **Post date:** [August 17, 2021, 12:51pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/7 "2021-08-17T12:51:15Z")
This may be a minor hijack, but exactly how does charging time fit into all this? Most airlines depend on the fact that quick turnarounds are possible with current aircraft. It would seem to me that this would be a significant consideration. Is there some special way to charge electric aircraft batteries in a reasonable amount of time? (Not to mention that airports certainly don’t want the aircraft parked at a gate charging for half the day.) ---
**Author:** ![Do\_Not\_Taunt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/do_not_taunt/32/2968_2.png) [@Do\_Not\_Taunt](https://boards.straightdope.com/u/Do_Not_Taunt)\ **Post date:** [August 17, 2021, 6:33pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/8 "2021-08-17T18:33:49Z")
Presumably, if you needed fast turnaround, you’d have some sort of battery-replacement technology. This never caught on for vehicles because of all the complexities around non-standardized parts, battery ownership, etc. But for a major fleet owner, like an airline, those issues could be non-existent or quickly solved. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [August 17, 2021, 6:55pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/9 "2021-08-17T18:55:30Z")
> [@Do\_Not\_Taunt](#): > > Presumably, if you needed fast turnaround, you’d have some sort of battery-replacement technology. I have severe doubts about swapping batteries being feasible. The main reason is the size of the battery in an airplane. They’re going to have to be way too large a percentage of the plane’s weight. For example, the [Eviation Alice](https://en.wikipedia.org/wiki/Eviation_Alice) has a 3700 kg battery, which is 60% of the plane’s weight. You’re going to swap all that out in half an hour or so? It’d be easier to swap planes. Another point against it is that the plane would have to be designed to allow quick access to the battery. That’ll add dead weight to the plane, and I shouldn’t need to point out that weight is at a premium on all planes, although especially so for electric. ---
**Author:** ![Do\_Not\_Taunt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/do_not_taunt/32/2968_2.png) [@Do\_Not\_Taunt](https://boards.straightdope.com/u/Do_Not_Taunt)\ **Post date:** [August 17, 2021, 7:17pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/10 "2021-08-17T19:17:34Z")
Yeah, you’d clearly have to design the plane for easy access. I’m not sure why that would necessarily increase overall weight. And I’m not sure why 3700kg would be a problem. It’s not going to be people doing it - it’s going to be some sort of crane system that extracts it (which could be two or more separate batteries, if that’s easier to design) and drops a new one in. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [August 17, 2021, 7:37pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/11 "2021-08-17T19:37:49Z")
I won’t say that it’s impossible to design a plane to have a quick battery swap but not involve an increase in weight. But it’d be a challenge to do so. They’d also probably have to have specialized lift trucks to extract and insert the battery. And extra personnel to run this and inspect it afterwards to make sure the new battery is properly in place and hooked up right. But this is all so that 20 or fewer[\*] passengers (and their luggage) are not inconvenienced by having to change planes. Still looks like it’d be much easier (and less expensive) to just swap planes. . [\*] It’s going to be quite a while before electric airplanes will be large enough to carry more than about 20 people. Even getting to that large a plane will be a challenge for today’s battery technology. ---
**Author:** ![md-2000](https://avatars.discourse-cdn.com/v4/letter/m/9d8465/32.png) [@md-2000](https://boards.straightdope.com/u/md-2000)\ **Post date:** [August 17, 2021, 7:38pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/12 "2021-08-17T19:38:50Z")
Tesla V3 Superchargers will recharge a battery (Model 3 70kWh) in 20 to 30 minutes. Presumably, with the right chargers the airline could recharge from the moment the plane pulls up to the gate. Not many aircraft turn around in less than an hour. Still, that would be a helluva lot of power in a short time. As for range, from their FAQ: > #### What’s a typical route that the ES-19 will fly in 2026? > > Our early adopter market will be very short flights where there is high demand. This will include island-hopping and flying over mountainous terrain, where the flight distance is significantly less than the road routes available. > #### What are typical early routes in the US? > > Examples of routes include Chicago O’Hare International Airport (ORD) to Purdue University Airport (LAF), which is 191 km, and San Francisco International Airport (SFO) to Modesto City-County Airport (MOD), which is 120 km. > **What are typical routes in the Nordic countries?** > Typical routes in the Nordic countries include Stockholm-Visby, Bergen-Stavanger, Skellefteå-Vaasa, Trondheim-Östersund, and Gothenburg-Copenhagen, as well as all domestic flights on Iceland and Greenland. It says nothing about 250mi range is with or without reserve. But the direct distances are ORD-LAF 121mi; SFO-MOD 78mi; Visby to Stockholm is 139 mi.; if the cost of flying is low enough, this electric aircraft could be an adequate substitute for small commuter flights on medium to low-load routes. I guess the question is whether a 19-passenger flight would pay for itself - but with far less fuel or engine maintenance costs, it is very likely in some settings. The main advantage is to feed those potential passengers into their airline system for flying further, if their choice was to drive to the big airport 3 or 4 hours away. (Plus bypassing slow travel driving through an urban environment.) I don’t know the exact ratio, but for example a Tesla with almost a ton of battery (total model 3 weight - 1830kg) has the same range as a vehicle with (at 30mpg) 10 gallons, or 70lb of fuel. It will be a while before batteries are even close to the “energy density” of petroleum products. But, as pointed out, the maintenance and wear and tear (and the weight of the accompanying engines) are much less with electric. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [August 17, 2021, 7:49pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/13 "2021-08-17T19:49:30Z")
> [@dtilque](#): > > [\*] It’s going to be quite a while before electric airplanes will be large enough to carry more than about 20 people. Even getting to that large a plane will be a challenge for today’s battery technology. Don’t larger aircraft use less fuel per payload-distance? So wouldn’t it actually be easier to start large for battery aircraft? ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [August 17, 2021, 8:59pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/14 "2021-08-17T20:59:15Z")
> [@](#): > > It says nothing about 250mi range is with or without reserve. That’s a red flag to me. This is what they say: > [@](#): > > Reserve, alternate, and contingency energy (fuel) requirements vary by geographical region, and by the type of operation being flown (VFR, IFR, etc). In addition, for short range operations, there are procedures for reduced contingency fuel, and for no alternate depending on the specific route. That’s a lot of weasel words instead of just saying “Our airplane has a range of X with IFR reserves, Y with VFR reserves, and up to Z with special short-flight reduced reserve requirements.” I take that to mean that 250 miles is max range, period. Reserves will have to come out of that. That’s also consistent with predicted ranges from other electric aircraft startups. It’s also important for everyone to remember that **this is currently a CGI airplane**. I was going to say ‘paper airplane’ to denote one yet to be manufactured, but according to them they are a year away from even a Preliminary Design Review, so all their stuff right now is best-case, theoretical, and probably massaged by marketing. Take this whole thing with a huge grain of salt. Also, beware of any high technology company making bold promises while having nothing to show but renderings or simple mockups. They are often organizations designed to extract as much government and private investment they can, with an actual product maybe coming later. Real engineering companies work on show-stoppers which may not be glamorous. Investor scams spend their seed capital on fancy mockups and CGI renderings for web pages. And there is an ocean of ‘green’ investment money coming down the pike, and everyone wants in on the action. This scam in various forms has been around forever. I can’t count the number of paper airplanes I’ve seen come and go with lots of hype but never a finished product. Anyone remember the Moller Skycar? How about the SoloTrek XVF or whatever it was called. The Moshier 400 was a precursor, advertised for over a decade and never produced. But they did sell nifty $50 ‘info-kits’ to excitable people, which turned out to be the actual product. The info-kit scam pre-dates the internet. Back to the ES-19. To their credit, their performance numbers appear to be within the realm of possibility, unlike the eViation ‘Alice’. Especially if we assume 250 mi. range with no reserve. But that’s a pretty useless range unless they plan short VFR-only hops under a waiver to reduce reserve requirements. In that case, the airplane might feasible. In aviation, don’t start to get excited until,you see a working prototype flying roughly according to the paper specs. But don’t get really excited until they get a type certificate, because lots and lots can go wrong there. One thing about Harbour Air - they are doing their thing as a conversion of a certified airplane as an STC - Supplemental Type Certificate. That’s much less of a heqvy lift than a full type certificate. Cirrus Aviation had a very good, very safe light homebuilt aircraft they tried to certify. It nearly bankrupted the company and they wound up selling it to Cessna, which was big enough and experienced enough to shepherd it through the certification process. Certifying even a conventional airplane is a daunting task. Certifying a commercial plane with batteries and electric motors has never been done, and could take a decade or more. I’m not sure you can even ship lithium ion batteries in cargo due to fire risk, let alone having thousands of pounds of them operating at a high load inside the aircraft. Certifying the first electric airplanes will also require working out every failure mode, varioys procedures for emergency conditions, etc. Crash testing might be required for the batteries. Mantenance procedures have to be proved out, lifetime limits for batteries, TBO for motors, etc. I would bet $1000 that thus plane will not ge certified within 5 years of theirvestimate, if at all. ---
**Author:** ![Do\_Not\_Taunt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/do_not_taunt/32/2968_2.png) [@Do\_Not\_Taunt](https://boards.straightdope.com/u/Do_Not_Taunt)\ **Post date:** [August 17, 2021, 9:11pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/15 "2021-08-17T21:11:19Z")
> [@dtilque](#): > > But this is all so that 20 or fewer[\*] passengers (and their luggage) are not inconvenienced by having to change planes. Still looks like it’d be much easier (and less expensive) to just swap planes. No, that’s not what you’re avoiding. What you’re avoiding is having a significant amount of extra capital tied up in non-productive assets (a grounded airplane is a non-productive asset.) Maximizing time-in-air is a major concern of airlines, and I’d expect this to continue in a hypothetical future of battery-electric aviation. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [August 18, 2021, 6:15am UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/16 "2021-08-18T06:15:54Z")
> [@Do\_Not\_Taunt](#): > > No, that’s not what you’re avoiding. What you’re avoiding is having a significant amount of extra capital tied up in non-productive assets (a grounded airplane is a non-productive asset.) Maximizing time-in-air is a major concern of airlines, and I’d expect this to continue in a hypothetical future of battery-electric aviation. The battery you’re swapping out is now out of production. Based on EVs, that may be about a third of the cost of the plane. On top of that, you need to have at least one and probably more FAA certiified mechanics plus an FAA certified inspector to do the swapping. (Note that the 3700 kg I cited above was for a fairly small plane that will only seat 9 passengers. Larger electric planes will have bigger batteries.) Plus you have to buy any special equipment needed to do the swapping. It’s quite possible that having a plane out of service for a few hours while recharging may be less expensive. ---
**Author:** ![Do\_Not\_Taunt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/do_not_taunt/32/2968_2.png) [@Do\_Not\_Taunt](https://boards.straightdope.com/u/Do_Not_Taunt)\ **Post date:** [August 18, 2021, 3:28pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/17 "2021-08-18T15:28:44Z")
What on earth are you even talking about? How can a hypothetical future battery for a hypothetical future plane, which hasn’t even been designed yet - much less built - be out-of-production? Having a single rig to manage battery swapping for every plane that comes through a gate - and possibly servicing multiple gates if it’s mobile - is going to be cheaper in the long run than leaving every single BEV-plane idle while charging (or maintaining a significantly larger fleet so you can swap planes) so long as the charging time is greater than or equal to _x_. The value of x, of course, depends on a bunch of inputs: the cost of the swapping rig, the size of the battery, how much time the plane would be idle if charging weren’t a concern, the proportion of the plane’s value which is the batteries, and - the biggie - how fast it can charge. Maybe multi-megawatt charging speeds with become commonplace and it’ll be possible to fully charge the battery while the plane is unloading and reloading. But if not, there’s nothing unfeasible about doing swaps instead. ---
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [August 18, 2021, 6:05pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/18 "2021-08-18T18:05:36Z")
> [@Do\_Not\_Taunt](#): > > What on earth are you even talking about? How can a hypothetical future battery for a hypothetical future plane, which hasn’t even been designed yet - much less built - be out-of-production? “Out of production” is probably not the right phrase, and in this case means “out of operation”. That is, if a battery is being charged, or recharged then sitting waiting to be reinstalled into a plane, it is unutilized capital. ---
**Author:** ![Do\_Not\_Taunt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/do_not_taunt/32/2968_2.png) [@Do\_Not\_Taunt](https://boards.straightdope.com/u/Do_Not_Taunt)\ **Post date:** [August 18, 2021, 6:13pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/19 "2021-08-18T18:13:08Z")
Ah, “out of operation” makes sense in that context. That said, I’m not convinced that by the time we have BEV planes in actual, common usage (if that ever happens), that the batteries will be anywhere near 1/3 of the cost of the plane. Just going off the wikipedia article for the [Eviation Alice](https://en.wikipedia.org/wiki/Eviation_Alice), it looks like the plane is around $4MM with an estimated cost to replace the battery pack (after 3000 flight hours) of $250k. That’s 1/16, not 1/3. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [August 18, 2021, 6:47pm UTC](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977/20 "2021-08-18T18:47:04Z")
> [@CookingWithGas](#): > > “Out of production” is probably not the right phrase, and in this case means “out of operation”. That is, if a battery is being charged, or recharged then sitting waiting to be reinstalled into a plane, it is unutilized capital. Yes, thank you. That’s exactly what I meant. Do\_Not\_Taunt used the term “non-productive asset”, so I based my reply on that. I should have used the same term. [Next page](https://boards.straightdope.com/t/fuel-economics-of-battery-powered-airplanes/948977.md?page=2)