Revisiting Aptera's Efficiency

[@TailosiveEV]

Thanks for the shoutout Steve! Loved your breakdown 👏🏼

[@n.brucenelson5920]

Efficiency in our daily lives has become critical to our future.

[@hndit2u]

Hey Bruce or Steve. Unrelated to this video but a question is live to have answered. Will the rearview cameras have a washer system? I know that's a high end accessory but with no vision through the solar hatch having reliable rear camera views is essential.

[@n.brucenelson5920]

@@hndit2u Good question. I sort of doubt it. It could be that the aereodynamics will tend to keep dirt off. There will be a couple of rear camera veiws - one a wide angle one while in reverse.

[@christopherbarrett9749]

Hope you send a copy of your worksheet to Warren Redlich. He might need a refresher course for his napkin. You and Drew, are doing the math, which Warren Redlich does not understand. Thanks again for yet another deep dive, and explaining how to get to the truth. Efficiency is more important as resources are being used up!

[@DrTeeHenry]

Like certain other people we are familiar with, I don't think Warren Redlish is interested in facts or science. He starts with a conclusion and works backwards from there using... well, you know.

[@TailosiveEV]

I sent all my math to Warren (privately) before I made my video... he never responded and went straight to make his own video 🤷🏼‍♂ I think he's going more for clicks than real world data

[@christopherbarrett9749]

@@TailosiveEV A lawyer, who believes that he can make a one seat, podcar, better than Aptera, yet says no one will want a vehicle that only seats two. His logic is questionable there to, but my question is why is he dead set against Aptera? Neither he or Aussie Idea man, Vic, or other detractors can short the shares, so what is in it for them?

[@kevinscott8642]

@@christopherbarrett9749 Cranks, trolls… Never underestimate the power of stupidity.

[@kevinscott8642]

About a year ago, I told a friend about my investment in Aptera Motors. He looked it up and came back to me with concern for my investment, as he had watched a video by Mr. Redlich that had just come out at the time, claiming that Aptera was going to fail. I watched the video, and what I noticed was that Mr. Redlich showed not only a lack of knowledge of Aptera as a company, but also displayed a fundamental lack of understanding of business and finance. All while presenting himself as some sort of expert. I won’t be wasting any more time on, or giving any more clicks to, someone who is in the business of spreading misinformation.

[@ccibinel]

Disclaimer and Assumptions: I would avoid assuming the numbers are 100% accurate as some values are estimated. If some values are high and others are low the final range could be reasonably considered to be +-10% with reasonable certainty. That said the calculations can definitely show trends and potential of the design. -Rolling friction - Aptera will have low rolling resistance tires and less contact area due to 3 wheels. I assume they will have good but not unprecedented rolling resistance at 0.0085. Tires are available rated for 0.007 and typical car tires are 0.01 to 0.012. -Weight: We don't know the exact weight of the aptera beyond statements and trying to make the other information fit. I am using just under 2000lb (1537 for the vehicle and 455 for the battery). -Frontal Area: Tailosive did a recent video on the aptera and he concluded a ~21.7 square foot frontal area where my numbers are based on 23 (I measured 22.7 and rounded up). We have never had an officially stated spec for this but given the 3d printing model or photos and analysis I think 21-23 square feet is a safe bet. -Drag Coefficient: We know Aptera has repeatedly stated they will have 0.13 drag coefficient but given the need to keep mirrors (bloody NHTSA) and ability for small manufacturing differences like panel gaps to impact this I consider it optimistic in the real world. -Aux Drain. All EVs draw some power for computers and screens regardless of motion. I assumed this value as 200w which may be high but we simply dont know. All the controllers, cameras, thermal management etc need power. Other simulation sites like motor matchup dont even allow this to be set under 500w. Increasing this value higher can simulate the impact of HVAC systems for different temperatures but the exact draw under different conditions is tough to know. - Battery Size: For the LE we know the pack will consist of 6 modules of 416 cells. Assuming they are commodity 55e cells from EVE exact specs are available and used in the model - Battery Reserve: All EVs reserve a small percentage of the battery to obscure degradation and avoid going to absolute zero which can damage the battery. I assumed this as 4% for the LE. What we don't know is the amount of weight for the structure and bus bars in the battery but given claims about being very efficient I used a 20% estimate (arguably too optimistic). - Inverter/Drivetrain losses: Aptera needs to get the energy from the wheels to the motors. I believe Steve F stated in the past they will not be using highest performance inverters (I forgot the term) due to cost (very reasonable given the intended market). I used a somewhat conservative 85% for this (actual powertrain losses vary with speed - Elaphe has some nice graphs) Trying to make the data fit for the various models given available information on the battery sizes does not align to the stated ranges. The LE looks likely to over perform if the same conditions are applied to all the stated battery sizes (23,45,66,99 kwh) PS: Thank you for explaining make a copy right away; otherwise I get a ton of access requests.

[@ApteraOwnersClub]

Thanks for your spreadsheet Curtis. It's awesome

[@experienceaptera]

@ccibinel Great job Curtis! As a test I used your spreadsheet to calculate the theoretical efficiency of my Kia EV6 and the numbers match perfectly with my real-world performance.

[@deanmcmanis9398]

That was very helpful to review this efficiency spreadsheet. especially considering that there will be the big reveal of the PI model Aptera EVs (testing for and showing real world efficiency, range and safety) starting sometime in the coming months. It is not surprising to have many people doubtful of Aptera's efficiency claims because there is relatively little real world difference in range and efficiency among conventional EVs, short of giant, heavy, inefficient BEVs like the Hummer. One other point that isn't likely to be revealed in the math is that the production motors on the Aptera have been custom engineered by Elaphe for the Aptera. We saw this when Aptera changed their motor HP rating and 0-60MPH times for the Launch Edition AWD model. Elaphe had originally engineered their in-wheel motors to produce huge torque needed to move much heavier EV crossovers and pickup trucks, but the final production motors for the Aptera will be different. Designed to optimize efficiency, and to take advantage of Aptera's smaller battery pack and lighter weight.

[@madmotorcyclist]

There is three other things beside weight, air, and rolling resistances. You also have to account for gear lash and axle couplings loss of efficiency which don't apply to the Aptera but does to other EVs. The one other thing that both the Aptera and other EVs have to account for is synchronicity of the drive motors. If they have more than one drive motor and the EV doesn't properly maintain tire rotation of the wheels they control also will effect efficiency.

[@thatcher857]

Really looking forward to Chris Anthony’s TED talk! Bet it’ll bring in a ton of investors

[@christopherbarrett9749]

Are you sure he is doing a Ted talk? Hopefully you are correct, as that is a new audience. When is this event?

[@thatcher857]

No idea, but I heard Aptera will be doing a TED talk

[@DemaGeek]

Hats off to all the hard work involved here, the results speak for themselves.

[@glike2]

As an Aeronautical Engineer I can say you and others referenced (except the napkin guy) did a great job. The Aptera will be an electric cannonball run beast.

[@Sythemn]

Dunno where I got the numbers but I have 2.8m^2 for the frontal area and .13 for the Aptera. Assuming a constant speed of 62 MPH on flat ground, 35 PSI tires, and a 220 lb load, ~400 miles range should be expected on a full 40kw charge. I don't have the M3 in my spreadsheet to compare, but the Model Y would only make it ~180 miles on that same 40 kwh. Speed is a massive effect on expected range. Slowing down to 54 MPH jacks the expected range up to ~500 miles. 74 MPH drops it to ~300 miles. (Note, I used a PT efficiency of 100% for both which isn't realistic and would likely lead to a bigger % difference between these.)

[@karlschleifenbaum5793]

Half the energy need is magnificent. The numbers seem to check out

[@biondanishgenomeinstitute8193]

One reason to believe Aptera is that they must know already from their own driving. They must have tested it.

[@MIRAGEDEALER]

I don't believe the bald headed troll. I will believe the match. That guy was full of it.

[@unclegeorge7845]

Gosh! Now this is a bunch of numbers. I found it really interesting to see all the math that backs up some of the numbers that Aptera puts forth. 10 miles a KW will be fun. [ctrl]+z gives you an undo function. Really fun for these "what if" scenarios. I'm sure Apple has a similar option. Split screen just might reduce the car sickness that jumping around a spreadsheet can give some of us.

[@jamesengland7461]

Half the car. One less tire. More slipperier. er. Elementary 😂

[@DrTeeHenry]

Mathy is good. Very objective. If done right, it's hard to dispute. Thanks for revisiting this topic. Dealing with the nay-sayers is a bit of Whack-A-Mole, I'm afraid.

[@hammertlme]

This video feels like college again. Thanks teacher.

[@josephgallagher1440]

Thanks again Steve for your in depth analysis on each item and referring to Drew’s video as a higher level review!

[@johnvoules7447]

Thank you Steve. I thought you did a great job breaking it down for all to understand.

[@johntrotter8678]

Good summary. Curtis' spreadsheet is indeed enlightening and Drew's non-engineer summary was also good. That said, I will put on my science-based review mode and offer a few points: Review the any sort of discussion like this for three things: completeness, precision, uncertainty. Completeness: Rolling resistance is more than tires. It includes bearing resistance as well. Probably a smaller effect. Electrical efficiency is more than motor efficiency. It includes efficiency in AC-to-DC and DC-to-AC conversion in charging and discharging. Here, it is significant whether Aptera used silicon-carbide converters. I have seen discussion of whether they thought the added cost was worth the improved efficiency and I do not have data to show what they chose. It matters. Precision: My science and engineering professors would often cringe when we put down too many digits in our formulas. ("cringe" meant a reduced grade.) The point was always to put down the precision we actually knew, not the number of digits our calculator showed on the screen. It is surprisingly hard to do this and forces better depth of understanding. Curtis has several numbers where he uses seven significant digits. No, that fails to portray the real level of understanding. He can do better. Uncertainty: A more-complete story can be told by showing a range of inputs, commensurate with our understanding, rather than single-point values. Something like weight probably has a small range of values, but understandable. Coefficient of drag, baring real testing or detailed simulation of final design, probably has significant uncertainty. Exactly 0.13 is unlikely. A little better or significantly worse is more likely. Again, investigating what the uncertainty is will yield better understanding. Am I being picky? Of course, it's what I was trained to do. Will it matter? Yes, in the third significant figure or probably even the second. Not the first. (xxx Whr/mile) Did I miss something? Probably, but that's the point of comments.

[@BSingh-on4qr]

Woah, great comment. Good point about the significant figures; I'll apply that to my own engineering studies myself

[@paulevans4969]

The worst assumption made by Redlich was that drive train efficiency was equal between Tesla and Aptera!!! He doesn't understand the simplicity of the in-wheel motor in comparison to the complexity of the Tesla drive train. Two bearings and seals per wheel for Elaphe' motors vs motor, gear box, constant velocity joints, differential and drive shafts of a conventional EV. Oh, and I almost forgot the reliability of in-wheel motors vs. complex drive trains.

[@ccibinel]

Completeness: I decreased the powertrain efficiency in my model from 90% to 85% to account for the inverters about a month ago. I retitled the powertrain efficiency field to include both. Aptera will not have silicon-carbide inverters per an interview with steve a few months ago. Precision: I simply didn't set the cell formatting on some things and the results is excessive numbers of digits. Doing the calculation results in excessive precision; this was not intended to be a pretty user friendly website like motor matchup. I made this sheet to sanity check the numbers and see if Aptera would do excessively poorly at speed or on rough roads. Uncertainty: I was using 0.14 in the sheets until recently. Steve and Chris have stated the 0.13 Cd number repeatedly in interviews so it seems they have more confidence in it recently.

[@ccibinel]

​@@paulevans4969 Aptera is a new unproven powertrain and while it is possible it could have higher motor efficiency they will be using worse inverters so I wouldn't assume Aptera would have an advantage here. It will probably be +-2.5 % either way which means ~10 miles of range at most for the LE.

[@BennetYee]

in the days of hand calculations keeping intermediate values short -- the right number of sig-figs -- can make calculation easier/faster. these days computers keep all available precision, and nobody rounds intermediate values in their code (or spreadsheet formulae). there is no "excessive precision" per se, just missing error bounds which is what sig-figs are intended to convey (an approximation thereof, rather than actual error bounds found using numerical analysis). yes, maybe the final output value should have been formatted to display fewer digits. except that in exploratory spreadsheets like this, it's not always clear which values are "final" outputs. but this is how having a copy of the spreadsheet can really aid understanding. for both precision and uncertainty, we can change the inputs to see how sensitive the computed outputs are, without actually doing the numerical analysis. to get the feel of the math, without grinding through the numerical analysis. there's no need to repeat the calculation in the spreadsheet w/ a range of values when you can just change the values yourself!

[@rfolea2]

Drag force does vary with the square of the speed, but power needed to overcome that drag force varies with the cube of the speed. From Wikipedia[0]: "Note that the power needed to push an object through a fluid increases as the cube of the velocity. A car cruising on a highway at 50 mph (80 km/h) may require only 10 horsepower (7.5 kW) to overcome aerodynamic drag, but that same car at 100 mph (160 km/h) requires 80 hp (60 kW).[16] With a doubling of speed the drag (force) quadruples per the formula. Exerting 4 times the force over a fixed distance produces 4 times as much work. At twice the speed the work (resulting in displacement over a fixed distance) is done twice as fast. Since power is the rate of doing work, 4 times the work done in half the time requires 8 times the power." Power output is directly felt by the rider, so it's the more relevant comparison here, and your comment is more practically useful. [0] en.wikipedia.org/wiki/Drag_(physics)#Power

[@ccibinel]

Thanks for including the reference. I'll look into this and correct the equations if I can corroborate a flaw in the formula I used - probably take me a few days given work and commitments the next few days.

[@wingsounds13]

But when traveling one tends to travel for a given distance, not a given time. If you travel 100 miles then we are considering the power expended over that distance. Doubling the speed may be 8x the power, but expended over half the time, thus 4x the Watt Hours. Feel free to explain where I have gotten this wrong.

[@ccibinel]

@@wingsounds13 Thanks

[@iansmith6728]

Regarding the bike tyre thing, road bikes are slowly moving from 23c to 28c due to lower rolling resistance and more comfort. That suggests that the friction/rolling resistance of the 28c tyre is less, potentially due to a smaller overall contact patch.

[@elchupacabra1666]

Contact patch is same, regardless tire width at the same tire pressure. Difference in rolling resistance comes from sidewall deformation and rubber hysteresis accompanied with it. Wider tires has less sidewall deformation at same pressure therefore lower rolling resistance but bigger air resisitance due to bigger frontal area. 28 mm is somewhere near to sweet spot for efficiency for a road bike. Example in this video about bike tires and rolling resistance is somewhat misleading.

[@artboymoy]

I watched Drew's video but I like this mathy one as well.

[@a5-30-31cts]

Thanks Steve for another landmark Aptera vid! As you know high-end, $3,000 -$10,000 road bikes are probably among the most efficient forms of human transportation devices in the world. There are several factors that contribute to their amazing efficiency, but two of the most important of these factors are within the tires and wheels. Wheels: Mass/weight is removed away from the circumference (the rim) of the wheel. When a wheel is rolling, energy is required to accelerate/decelerate the mass at the circumference (outer edge) of the wheel up and down in a motion that forms a half sine wave pattern ("nnnnn"). The less of this, the better in terms of rolling efficiency of the bike. Tires: Since tires are at the wheel's circumference, the lighter the better (as you already mentioned in your comparison of knobbies versus road tires). There is also another factor: tire carcass construction - notably Threads per inch (TPI) of the carcass. The more TPI, the better able the sidewalls will be able to flex without the friction of threads rubbing against each other as with the case of a low TPI tire. The difference this makes between tires of same brand and size is remarkable. For instance, a comparison between Continental's $30, 60 TPI, Ultra Sport 330 gram, 700x23c clincher versus Continental's $150 ,220TPI, Grand Prix 4000 208 gram, 700x23c is remarkable. The Grand Prix just roll like ice skates and feels self-powered and you're hardly pedaling. In contrast, the Ultra Sport feels like you're rolling over molasses and you're pedaling hard constantly to keep up with the same bike with the GP 4000 tires. Tubeless tires also decrease circumference weight. On a the Aptera I bet that if a special tubeless, puncture resistant tire with such efficiency considerations could be developed for the Aptera, perhaps it would add over 10% more range? (A higher pressure tire (e.g. 70-75psi) would likely require re-calibrated shocks).

[@ApteraOwnersClub]

I've never tried expensive tires on my bike. Do they really make that much of a difference?

[@a5-30-31cts]

@@ApteraOwnersClub Hi Steve! My brother-in-law who owned a bike shop in Santa Rosa, taught me a lot about bikes and I began building/re-building close to 100 road bikes for church friends between 2014-2018. I've slowed down since then and now am dabbling in e-bike conversions. A lot of the upgrades for these people was focused on the wheels/tires, then drivetrain, then ergos. The difference a tire upgrade would make depends on the tires that are presently being used. There is generally a tradeoff between efficiency versus longevity/puncture protection. Also wire-bead (non-folding) versus folding tires is a big factor. Folding tires are better than wire bead tires. In the old days the most efficient tire was racing a "tubular" or "sew-up". But those are gone. Now tubeless clinchers are the most efficient offered. Also changing, is the tire size. Formerly 700c x 23c and 100-180PSI was the standard, Now larger width 700c x 28c or 32c and 80-105psi are the preferred tire width (700c x 32c was considered cyclocross size tire, but now is the norm for road tires: Some example clinchers brand/models (that I've actually tried) from the most efficient (and listing their drawbacks): 1. Vittoria Open Corsa CX - 320tpi, 150psi, 180gr Pros: This is close to the most ridiculously low rolling resistance tire out there. Cons: Very thin thread, very little no puncture protection. Flats easily, and will last no more than a few hundred miles. Mainly to win races. (But so much fun!) I have my set to use as a standard and for thrill rides. 2. Vredestein Tri-Comp Fortezza 120tpi, 175psi, 230gr. Pros: has the most "tubular feel" (very round profile, neutral steering). Nice sound, Great plush feel. Fun! TriComp Fortezza model may have been superseded, but successors carry on the these qualities. My Fav. Cons: a bit heavy, Despite puncture belt, still gets flats. 3. Continental GP4000 180tpi, 125psi, 200 grams. Pros: low rolling resistence fast tire. Good puncture resistance. Used by many for racing. Long lasting., Light weight. Cons: Has a non-round "pointy" "V" shape profile that kind of feels like it "falls" into turns (opposite of the Vredestein). 4. Kenda Kaliente Pro 120tpi, 130psi, 205 grams Pros: fast, low rolling performance on par with all above, but at budget price. Decent puncture protection. Cons: None I can think of other than lacking any distinctive character. Tires with puncture protection: 1. Continental Gatorskins (folding): pros: lightest, 2. Schwalbe Marathon (I'm running Marathon Supreme on e-bike. has same low rolling resistance as Gatorskins, but more protection 3. Specialized Armadillo: Most bullet proof, but quite heavy tire. Ways to add puncture resistance: 1. Mr Tuffy Tire liners 2. Slime (make sure bike is parked with valve stems are positioned at the top.

[@a5-30-31cts]

@@ApteraOwnersClub What tire are you presently running? Maybe a Continental Gatorskin 700x25 or 700x32 is best for commuting (don't want flats on a commute. Gatorskins are not that great in wet. Schwalbe Marathons are great commuter tires with low rolling resistance and better protection than Gatorskins. I have the Marathon Supreme 700x32c) on my e-bike. They're great.

[@ApteraOwnersClub]

I run the cheap Continental ultra sport 2

[@milohobo9186]

At some point the weight of the occupant and/or cargo has to be assumed. I just say put it at 400 lb for occupants and cargo combined weight.

[@richpate9436]

This week's class in high efficiency automotive EV engineering is especially interesting. I feel like I need to be paying tuition. Oh, wait. I am (supporting member). Thanks.

[@NeilBlanchard]

Most important thing for vehicle efficiency - is drivetrain efficiency. The lack of reduction gears and driveshafts means the Aptera will have a bit higher efficiency than other EVs. Some hub motors are as high as ~98% efficiency. I don't know what the number is for the Elaphe motors. Reduction gears can lose 1-2% I think? And spinning the mass of the drive shafts (and their flex) also loses a bit of energy. This is why EVs are so much more efficient than ICE vehicles. Second most important factor for vehicle is aerodynamic drag. Total drag is total frontal area X coefficient of drag. So with the outboard wheels, the Aptera has a smaller frontal area. The VW XL1 has about 16sq ft - the lack of optical side view mirrors subtracts about 1sq ft (total for both mirrors) and this lowers the Cd by about 0.01, which is much more significant than it sounds. Aptera has said that a majority of the drag is coming from the front suspension, and the space between the wheel fairing and the main body. An aside - I have been following Aptera from the very beginning, and on that first design they went from RWD to FWD - and the round drive shafts alone added something like 0.03 or 0.04 to the Cd. A spinning round shaft is pretty awful for aerodynamic drag. This is another advantage of the in-wheel motors. For every mile you drive a 25sq ft vehicle - you have to shift about *4.5* TONS of air out of the way. Third most important factor of efficiency is weight. Accelerating a mass takes energy, obviously, and more mass/weight is worse. Wheel/tire weight counts "double" - it is part of the overall mass that has to be accelerated, and they have to be spun - even if the tire is off the ground, it would take energy to spin. Fourth most important is rolling resistance - and weight is a large contributor to RR. Wheel alignment and brake drag and bearing friction are other causes of rolling resistance; in addition to tire deflection. Even tread squirm is a factor - newer tires have higher RR than worn tires.

[@chrisrudzinski6241]

The LE Aptera is expected to weigh 2200 lbs per CA's more recent interviews.

[@RileyLinch]

As a mostly blind person, I've never heard "sightless" used in regular conversation but really appreciate it. Would've loved to have you as a teacher.

[@brianrosenlof388]

Really great video, and something I've really wanted to see for awhile now. Thanks for putting this together!

[@wingsounds13]

Very nice presentation. Those outta the ass hit jobs need to be debunked. I think that it's kind of funny the number of people who will believe nothing about Aptera's efficiency predictions - they MUST SEE numbers from physical real world tests or it's all a lie. Computational analysis has gotten pretty good and I would be surprised if real world testing results differed by more than 5% or so.

[@johnhartge]

Thanks!

[@ApteraOwnersClub]

Thank you!

[@johnt6508]

Nice video. I trust that Aptera engineers did their math right, AND, i trust management to be open and transparent about their expectations. As with everything, the real vehicle might vary some from the projections.

[@Bob_Sacamano]

I wonder how much the removal of the side mirrors will affect frontal area.

[@GNiessen]

The STL file might not be that accurate as they thickened the wheel linkages and the side mirrors to make it a less fragile model. But for the sakes of your exercise, probably fine.

[@ccibinel]

I actually don't think they did. I did for my unofficial patch bit their version seems like it might be accurate.

[@WyndStryke]

I seem to recall ChrisA saying recently that they've been working on the aerodynamics of the wheel linkages. So the CD may have actually improved since the STLs were generated. It'll hopefully all become clearer once the PIs are here, and are undergoing aero/range validation.

[@Sqeptick]

That Tesla shill is one of the biggest misinformation dorks on the internet. He should probably stay away from math.

[@FromPovertyToProgress]

Excellent analysis. Your point on tires raises an issue of what type and brand of tires that the Aptera will use. Has that been established? Tires are one of the most important parts of the car, and there are large trade-offs between cost, performance, rolling resistance and longevity. Many car companies either go very cheap or choose a tire that boosts performance or mpg. Both choices can seriously undermine longevity. I hope Aptera makes a wise decision on tires.

[@DaBinChe]

Tires was mentioned in a previous video..Think it was Chris Anthony that said which brand/size. I recall a Korean brand. The Korean tire companies are ahead as far as making tires for EVs, they have more choices for EV than anyone else.

[@wingsounds13]

In a video that listed shipper information I noted that Aptera purchased a lot of 50 Hankook 195 50R16H L,B,I-HK. These are probably the tires being used on prototype builds and likely the Production Intent builds too. I am uncertain as to whether these are their final choice for production.

[@mikegrok]

HVAC energy usage... My chevy cruze was recently killed by a deer. It's AC unit was 2.2kw, and it was not able to keep up with hvac demands be it cooling or heating. The aptera will have a 2kw compressor but paired with a variable speed motor. Chris said that it should take about 200w to maintain a comfortable temperature inside when it was 95f outside. Also they are putting all of the components inside of the thermos instead of outside like other vehicles.

[@theproffessional9]

The thing I wonder is though does the Aptera have a heat pump? I don't remember if it did, but if it doesn't it's going to take a massive hit to the range in the winter, especially wince the battery is half the size of the average EV.

[@harrygysland1517]

The spreadsheet doesn't seem to include the affect of the solar panels. When the panels are modeled for a sunny day by changing the AUX DRAIN to 0 the decrease in range at speeds lower than 20 mph disappears. If its modeled on a brighter day when the drain is -200 watts then it goes to infinity at close to 5 mpg, so in slow traffic you're gaining energy. All three curves converge towards higher speeds as the drain influence is overwhelmed.

[@karlInSanDiego]

Regarding wheel count and rolling resistance, since the mass on the wheel is directly proportional to the rolling resistance, subtracting a wheel but retaining the same vehicle weight just increases the rolling resistance of the three remaining wheels. However less wheels does result in less rotational mass which is also an impact on efficiency. This is seem on EVs that have various wheel packages and is usually explained by the larger wheel and proportionally smaller tire has more mass. Sometimes less efficient, wider tire are contributors too. There was a human powered bicycle study done to determine the optimal wheel count. Regarding rolling resistance alone, more wheels were better, but when you added frictional losses of wheel bearings, and the aero penalties of where each wheel cut through the wind, I believe they arrived at 4 wheel with front and rears in line. Aptera obviously has light weight to its advantage regarding rolling resistance, but dropping a wheel and placing the odd wheel outside of the aero stream of the front two wheels is a disadvantage to efficiency.

[@aftonline]

The proof of the pudding, as they say, will be when people actually start driving these things. No amount of theorizing will give you real-world results. That's why we have EPA testing where they physically test vehicles to give them an efficiency score. But even EPA testing can give inaccurate results compared to people actually driving electric vehicles as Bjorn Nyland does on his channel, running the battery down until the vehicle stops driving and noting how many miles or kms were driven from full. Anything short of that is just speculation. It'll be interesting to see how long it takes Bjorn to get his hands on an Aptera after they are released in Europe. That will be one interesting video for sure 😊

[@wingsounds13]

Computer modeling has become quite accurate. Of course, real world efficiency numbers will be a little different, but I would be surprised if they are off by more than 5% or so. If you don't believe in computer modeling then you had better not get on a modern airliner. Modern commercial aircraft are ALL designed using computer modeling. Flight testing these days is primarily used to test systems and also confirm the computer models. Often the first article "prototype" off the assembly line goes into commercial service.

[@aftonline]

@@wingsounds13 There are a lot of variables that affect EV range, and with Aptera there are a few more, such as how much solar energy can be absorbed which in turn depends on the latitude, time of year, how cloudy it is, how much shading affects the parking location, also temperature which affects the efficiency of the solar panels. Then you have the usual things like the terrain, wind, temperature affecting the battery performance, aircon or heating usage, individual driving style etc. Not sure if Aptera will use a heat pump or resistive heating, but that is going to affect efficiency in cold weather. So, the point of saying all that is that you can't just give one figure for range, like you are always going to get 250, 400, 600, or 1000 miles depending whatever model Aptera you are driving. If you are in subzero temperatures and have to preheat the car, or in 30 degrees C or more, and need to run the aircon continuously at full power, that's going to eat into your range. I am not sure whether 400 miles is the maximum range for the Launch Edition vehicle, for example, or is it a median, like maybe it varies in a range between 350 and 450? These are things that people will only find out from experience.

[@wingsounds13]

@@aftonline what you seem to be saying is that range ratings for EVs are meaningless because real world use will be different. The range rating given is just a base reference, and yes, Your Mileage May Vary. It will be interesting to see what the EPA range is on the production article, though as most of us know this is often a Wish rather than You Will Get.

[@ccibinel]

​@@wingsounds13 tests of evs (especially in winter) have shown huge variation in real world even when trying to compare apples to apples between different vehicles. Epa numbers have a variety of calculation methods and tesla is routinely toward to worst for real vs epa. That said if Aptera can be 400 km real world I'm good.

[@jeffcarlton3590]

Thanks! So can we learn with these tools how the AWD & FWD versions of the 4 Aptera battery sizes might vary in efficiency? Aptera seems to be advertising this fixed ~10 miles per kWh efficiency value, seemingly across all 8 of these builds. Physics of course should require that for max efficiency: FWD 250mi > AWD 250mi > FWD 400mi > AWD 400mi > FWD 600mi > AWD 600mi > FWD 1,000mi > AWD 1,000mi. Aptera's customers really should know the estimated mi/kWh, or MPGe for these eight build options, albeit modeled to start with.

[@seanclark2703]

there is a phrase out there.... "Prove to me you are not a camel"... you spend so much time doing that, that you're distracted from your real goals...

[@deanstewart2]

Did I miss it, or has Aptera not released the results of the Pininfarina wind tunnel test? I was hoping to hear confirmation that they hit their Cd target of .13.

[@WyndStryke]

They haven't done the full tests yet, as far as I know. The Pininfarina session we saw was basically a test run for figuring out how to set up the wind tunnel with a 3 wheeled vehicle, etc.

[@michaelbramel5771]

IIRC they said that the wind tunnel results for Gamma would be preliminary, and they wanted to have PI build results before releasing the numbers to the public.

[@richardryley3660]

​@@shrimptopian3392I am pretty sure they cannot legally sell a vehicle with completed crash testing. They may release those first production vehicles without verifying their performance characteristics, but since they will be production vehicles the stats will still apply to them once they have been verified.

[@jeffcarlton3590]

@@shrimptopian3392 No! They will transparently test and prove their P.I. builds prior to customer production. That is the whole point of the P.I.'s and our end of this year wait time! Where did you conjure up them "want(ing) to deliver" a "car this year" that "will be untested and unproven on all fronts" from?

[@kimbowilco]

Good job as always (-:

[@ddessert6]

As you point out, the speed of the vehicle is critical. Aptera's claim of 100Wh/mi is at "highway" speed. This is a huge variable as the EPA will measure highway speed to a max of 60 mph with an average of 48 mph. Now we all know that is very unrealistic as you would be run over even at 60 mph on the highway today. If you actually measure your average speed on a road trip, you will be surprised to find that your average speed will actually very close to 48-50 mph even though we might be driving 70-80 mph. (Traffic and on/off ramps really will dig into that average.) If we take Curtis's spreadsheet and use 48 mph for the Aptera, it is very difficult not get 100Wh/mi or less, using realistic numbers. (Less is better.) If Aptera is measuring the efficiency at 48 mph, that is what the EPA will do and what the vehicle will have on the window sticker. (I would also increase the weight of the vehicle and passenger(s) so the total is closer to 2,200 lbs. The average weight of an American male is 197.6 lbs.) Thanks Curtis for the spreadsheet. The cool thing with this is that we can figure out the weight of the battery pack for the most part. There are some unknowns as what the cooling system will weigh but Chris & Steve have recently said that it should come in around 2,200 to 2,300 lbs which seems more realistic to me.

[@EnmandsBand1]

it's difficult to sell Aptera on efficiency when all people care about is range but I hope this will change when they realise that efficiency equals the actual cost of your daily driving. I would love to get an Aptera to replace my Ioniq (which is still the most efficient EV and has been since 2017!) but I'm not sure I can wait until they get it to the EU market.

[@namenotshown9277]

I remember an interview with chris anthony, where he mentions the nasa wind tunnel test, and he says the engineers were amazed, but i'm afraid there has never been any proof of data of this test, so I think its unlikely nasa guys even said that. They also were saying at one time the italian wind tunel test was going to verify their claims, but that turned out to be a photo shoot. Take with a pinch of salt whatever they claim. Now there might be some evidence though of a test done for the x-prize where they cars had to do a roll down test ( can get an estimate of cd from that), I've looked for the data but cant find as alot of the xprize sites are gone now. Surely its about time aptera gave some proof of their cd value claims.

[@alansnyder8448]

Efficiency is the reason I want an Aptera. It means less energy used per mile on my commute, less time to charge back up for that same distance, and less impact on the environment. As I say on every comment, I'm not interested in solar panels, so hope there is an option not to have them.

[@eddiedelahoz]

After my own nerdy heart

[@makesaveinccomm]

I needed Aptera points please... thanks a lot

[@jamesengland7461]

Redlich claims 50% weight loss equates to 10% range increase, even though it's directly proportional to weight, requiring at least a doubling of range, further divided by ~0.75 because of using 3 wheels instead of 4, therefore the mass component of range is ~2.67 times greater with Aptera. As you mentioned, frontal area is roughly equivalent, and aero range component is directly proportional to Cd.

[@speciesofspaces]

Funny that's the opposite in bicycle tires as some will know from recent data and testing. In other words, the wider bicycle tire has a wider but still shorter, thus, smaller contact patch than say the "old school" skinny tires which have narrower but longer contact patches. Therefore, a 28c tire is going to have more rolling resistance than say a 35c tire etc. It sounds counter intuitive but only if you have always assumed the lighter weight tire was absolutely faster but between the said tire sizes weight is not a huge factor when compared to tire patch size and rolling resistance.

[@jeffcarlton3590]

Yes, counter intuitive indeed. Why would skinny tires have longer contact patches? In the Tour de France they are inflated to 115 to 135 psi varying for max efficiency and power delivery by front/back and stage of tour needs. Why are increased weight and air resistance negligible factors?

[@speciesofspaces]

@@jeffcarlton3590 Indeed in the Tour they mostly all ride wider tires now anywhere from 25c to 32c etc. And tubeless which allows for even lower tire pressure.

[@RomanChaar]

obviously the aptera pushes a lot less air around than a model 3 and has one less tire, and weighs significantly less, but does that equate to 2.5 times more efficiency than a model 3? I'm just guessing and saying maybe the aptera will be at most twice as efficient than a model 3. We still need to wait for a 3rd party validation and still not a single validated vehicle built......still waiting.....it's only February 2024.

[@richardryley3660]

Unless you're saying that the Aptera will break the laws of physics in order to underperform, I'd say you don't have anything to worry about. The whole point of science is that its results can be predicted, and then verified by comparing those predictions to real world data. Wait for the test results instead of just saying that the calculations must be wrong because you feel like they should be wrong.

[@namenotshown9277]

thats an excellent spreadsheet, I note you skipped over power forward. A recent video shows 2amps and 387volts to get moving ( overcome resistance), thats 774 watts........if power forward means power to move from a stop, its almost spot on your spreadsheet says 0.78kw. This video you can see the data on the small screen ( I"ve worked out all the variables on the small data screen its pretty simple) kzbin.info/www/bejne/n5ebYn-Pjryqpbs If you want to know what all the variables are I can list them.

[@Bgood2elbow]

Hi Steve, here is a little calculation that I did. I don’t know if I made any mistakes or did not take all of the costs in account, but tell me what you think. Cost comparison of Aptera vs. Nissan Versa for commuter This estimate has been made to determine if Aptera will be the most affordable commuter vehicle on the road (including ICE cars). The “break even point” compared to an affordable internal combustion. This first calculation is comparing the Nissan Versa (considered to be one of the top rated affordable commuter vehicles based on cost of the vehicle, maintenance, and fuel consumption). These are back of the napkin calculations, but demonstrate that by year 7 (about 100,000 miles), the cost of the Aptera becomes less than that of the Versa. Estimated cost of Aptera 250 mile w/ full solar pack: $26,800 Cost of base model Nissan Versa (2024): $17,660 Average of 40 miles per day for 365 days: 14,600 miles per year Cost of oil and filter changes every 7,000 miles on Versa: $100 National average gas cost (2/12/2024): $3.196 per gallon Versa gas mileage (listed highway): 40 miles/gallon Cost of tire changes on Aptera (195/45 R16, $56.93 per tire, 60,000 miles, times 3): $170.79 Cost of tire changes on Versa (205/55 R16, $58.97, 60,000 miles, times 4): $235.88 Cost of brake changes on Aptera at 100,000 miles (because of regenerative braking): $ $75 Cost of brake changes on Versa at every 70,000 miles: $100 Versa timing chain replacement (120,000 miles): $655 Aptera replacement battery cost? Not known, but I go into this again at the end of this comparison. This assumes recommended maintenance at the long end for the Versa and no breakdowns by either car. Day one: Aptera: $26,800 Versa: $17,660 Year one (14,600 miles): Aptera: $26,800 Versa [car cost+gas+2 oil changes]: $17660+1166.54+200= $19,026.54 Year two (29,200 miles): Aptera: $26,800 Versa [car cost+gas+2 oil changes]: $19026.54+1166.54+200= $20,393.08 Year three (43,800 miles): Aptera: $26,800 Versa: $20,393.08+1166.54+200= $21,759.62 Year four (58,400 miles): Aptera: $26,800 Versa: $21,759.62+1166.54+200= $23,126.16 Year five (73,000 miles): Aptera: $26,800+170.79= $26,970.79 Versa: $23,126.16+1166.54+200+235.88+100= $24,828.58 Year six (87,600 miles): Aptera: $26,970.79 Versa: 24,828.58+1166.54+200= $26,195.12 Year seven (102,200 miles): Aptera: $26,970.79+75= $27,045.79 Versa: $26,195.12+1166.54+200= $27,561.66 Year eight (116,800 miles): Aptera: $27,045.79 Versa: $27,561.66+1166.54+200= $28,928.20 Year nine (131,400 miles): Aptera: $27,045.79+170.79= $27,236.58 Versa: $28,928.20+1166.54+200+235.88+655= $31,185.62 Year ten (146,000 miles): Aptera: $27,236.58 Versa: $31,185.62+1166.54+200+100= $32,652.16 Now the question is battery replacement on the Aptera? We don’t know the cost and we don’t know time, but if it is between 100,000 and 200,000 miles it should be about now. To make the car cost exactly equal in costs at this point (ten years), the battery pack replacement would have to cost: $32,652.16-27,236.58= $5,415.58 This calculation does not consider insurance costs (which maybe cheaper for an auto cycle compared to a four wheel vehicle). I could not put a graph in the comment. Tell me what you think or have other factors to consider.

[@ccibinel]

Aptera is definitely far more fun than driving a Versa. I really think they are missing the sports car marketing angle in overemphasizing solar. Aptera is a fast and nimble vehicle compared to 90+ % of the things on the road. Unlike most sports car Aptera is affordable, electric and has storage.

[@Bgood2elbow]

Good points. You could also argue that the Versa is a four seater. That could also be a factor for the buyer, but most people commute on their own.

[@josezayas6847]

Great video

[@billybruck]

I like "mathy"

[@pstoppani]

Seems everyone is mostly concerned about steady state vehicle speed when considering efficiency. I wonder how real world daily driving compares. Given that the average speed over time tends to be around 25MPH due to lots of stop and go traffic, it seems it would be useful to know these numbers.

[@ccibinel]

Elaphe has the powertrain efficiency heart graphs at low rpm and the regen breaking should be fine. Aptera is very light weight which reduces the impact of acceleration. Most of the same reasons the aptera range at a constant 20 mph is really good means in stop and go Aptera should do really well.

[@pstoppani]

@@ccibinel Understood. I'd just like to see some numbers that related to typical use.

[@WyndStryke]

For stop/go traffic in towns, aerodynamics is mostly irrelevant. Weight & the efficiency of regen-braking will be the biggest factors in that scenario. We know the weight (approximately), but we don't know the regen braking efficiency. The trouble with 'real world efficiency' is that everyone's experience will be different. I do most of my driving at highway speeds, with very few stops, for example.

[@ccibinel]

@@WyndStryke Everything is relative to other vehicles. We have no reason to expect that the Elaphe motors would be exceptionally poor at regen or low speed use. Given that the general model for travel at speed should be indicative of how well Aptera will handle the situation; not saying ~800 miles of low speed range will happen but we have no reason to believe Aptera has any glaring weakness.

[@WyndStryke]

@@ccibinel Yep, sure I agree, but I just don't think we have enough data to be able to predict it in a stop/go style environment. Highway driving is much easier for us to predict since they've told us the key information already. Aptera themselves will be able to estimate quite accurately since they'll know how the hub performs in that scenario. My hope is that a lack of a drivetrain will mean that regen is more efficient than other vehicles.

[@namenotshown9277]

95% is a hell of a good efficiency motor, I would go for 88 to 90%. Motor efficiency is heavily dependent on rpm also, each motor has an efficiency curve, at low rpm efficiency can be very low, maybe below 50% or lower. That might be one reason they are going away from elaphe as it will be spinning same speed as tyre, no reduction gearing, and it will be nowhere near in its highest efficiency range most of the time.

[@universeisundernoobligatio3283]

Looking forward to my Aptera. Efficiency should be good. My rooftop solar system will make it 100% solar powered , but its solar will be a minor contributor Ok with that.

[@jeffcarlton3590]

Over 6,000 miles per year is a minor contribution? Does your rooftop solar completely cover your home's electricity use? Consider using your 'home electricity plus Aptera' combined energy use when evaluating Aptera's overall contribution to your energy use footprint.

[@jeffcarlton3590]

Lacking a heat pump won't help Aptera but its smaller cabin area will. I will be exploring ways to add in a light thermal barrier in the coldest times of winter that isolates my Launch Edition’s cargo space which I will keep cold, from its passenger space where the heat ducts live. This barrier can be employed to increase efficiency and save costs on summertime cooling as well. Then, back to winter, more 'appropriate for winter clothing' combined with a lower thermostat setting are well known energy and cost saving measures. I save on car cooling in the summer with a spray bottle and fan-only cooling when it is not overly beastly. Evaporative cooling is often quite effective. At home my thermostat is set at 52 F and I do not heat rooms when they are not being occupied. I do not have thermostat controlled cooling at home, so fans and evaporative cooling are my only options. All that said, I am disappointed in Aptera's decision to 'heel drag' on their eventual heat-pump deployment. My 2013 LEAF has a great heat pump, beating Tesla to the punch by several years. Automotive heat pumps are decade-old tech. Aptera could start by on-boarding a basic off the shelf one and ramp up its efficiency and customization for Aptera's unique characteristics as time and money allowed. A 'hyper focus on efficiency' should be giving this issue higher priority. Hopefully they will be well along this maximized efficiency heat-pump journey by the time they are sending out their most efficient 250 mile, FWD build models. ‘Winter is a thing’ in most of their customer’s world.

[@universeisundernoobligatio3283]

@@jeffcarlton3590 The 6,000 miles per year if optimistic. An engineering design review of onboard solar panel real word output based on the light year and Aptera, by an engineer who drives a solar powered EV. kzbin.info/www/bejne/rnrSnIGkn9qUo5o

[@murthy90232]

Steve, thanks for all you videos. Recently, I came across videos on Aptera by @Aging Wheels and @Electrek Garage. These KZbinrs get to drive the gamma by themselves for a long time and give very useful experiential comments. Please review these and post your take on them.

[@danielhughes6896]

Aptera has a resistive heater so the Aux Drain will be much higher than the model 3 in cold weather.

[@jeffcarlton3590]

Lacking a heat pump won't help Aptera but its smaller cabin area will. I will be exploring ways to add in a light thermal barrier in the coldest times of winter that isolates my Launch Edition’s cargo space which I will keep cold, from its passenger space where the heat ducts live. This barrier can be employed to increase efficiency and save costs on summertime cooling as well. Then, back to winter, more 'appropriate for winter clothing' combined with a lower thermostat setting are well known energy and cost saving measures. I save on car cooling in the summer with a spray bottle and fan-only cooling when it is not overly beastly. Evaporative cooling is often quite effective. At home my thermostat is set at 52 F and I do not heat rooms when they are not being occupied. I do not have thermostat controlled cooling at home, so fans and evaporative cooling are my only options. All that said, I am disappointed in Aptera's decision to 'heel drag' on their eventual heat-pump deployment. My 2013 LEAF has a great heat pump, beating Tesla to the punch by several years. Automotive heat pumps are decade-old tech. Aptera could start by on-boarding a basic off the shelf one and ramp up its efficiency and customization for Aptera's unique characteristics as time and money allowed. A 'hyper focus on efficiency' should be giving this issue higher priority. Hopefully they will be well along this maximized efficiency heat-pump journey by the time they are sending out their most efficient 250 mile, FWD build models. ‘Winter is a thing’ in most of their customer’s world.

[@ccibinel]

100% but range ratings are done without heating or cooling on. The interior volume is small and the exterior materials are above average insulators so it should be reasonable. Some discussed the possibility of cutting up a hottub cover to seal the passenger area from cargo on the forums almost 2 years ago.

[@williamread8186]

I like this because Warren Redlich is so arrogant that his take on this is that he couldn’t himself design a vehicle that meets Aptera efficiency specs it must be impossible. Would you believe that this guy has moved to Thailand to find a young woman (

[@namenotshown9277]

wish I had come across this spreadsheet before, it is really great work, who is curtis? Aptera really needs to do some driving and show the results in some detail, since when driving these numbers are constantly changing and great in theory but in the real world are not that useful in getting actual range etc. Aptera has provided as far as I can tell no data, apart from saying 100wh/mile and 700watts solar , 40miles per day on solar alone etc....standard numbers that dont mean much in the real world Yes chris said nasa tested it, but has anyone ever seen the results from that nasa test......nope. I suspect there is no record of that every happening, if it had he would publish that piece of paper with the word NASA on it all over the place, he would have it hanging on his wall framed........did it even happen?

[@glike2]

The Cybertruck efficiency is disappointing but could be much better with narrower better aero wheels. An Aptera truck or van with superior efficiency would be able to raise the bar a lot.

[@casIIsac]

Warren was doing the same thing before Lucid came out. He is completely uninterested in the truth, only in Tesla being better and proving himself right.

[@lucianbakerii4047]

Wait a minute. Are you saying that a Tesla enthusiast would hedge the truth to placate themselves that their Tesla is one step removed from their messiah Elon? Really? ;)

[@markpetty9206]

Warren has heavily invested into Tesla stock shares. His information is very biased towards Tesla. Tesla share price has done poorly over the last year.

[@ccibinel]

Few tesla supporters are against Rivian, Aptera and others following in their footsteps. Legacy is failing and monopolies are bad for everyone. Most Aptera supporters are tesla owners or atleast stock holders.

[@glike2]

The napkin guy is very biased, seemingly an Elon/Tesla fanboy. I really appreciate Elon and Tesla's accomplishments to sustainable transportation but idolization is very unhelpful for objectivity.

[@thebigjr9995]

Lol. Love the level of arrogance of some people. As if Aptera would ever get the math wrong. In the end it might be +/- a couple of miles, but that's it.

[@thebigjr9995]

@@shrimptopian3392 ppl on both sides are waiting for that day I think.

[@richardryley3660]

Great example of the Dunning-Kruger Effect. "The Aptera is wider than the Tesla Model 3" Yes, because the wheels are located out AWAY from the body in fairings. You do not count the space between the body and the fairings. Putting it another way, the air flows around the body and each of the two fairings separately. You would add the air resistances for each of the three shapes together.

[@ericstarmer7779]

and add in some interference drag....

[@richardryley3660]

@@ericstarmer7779 I would expect very little of that since the body only becomes as wide as the track well behind where the wheel pants end. Any turbulence would be reflected in the drag coefficient.

[@ericstarmer7779]

Great example of the Dunning Kruger effect - I happen to have a degree in aeronautical engineering - how about you...... @@richardryley3660

[@santanumaitra3962]

Great job Steve! Unfortunately, the gentleman you are trying to talk sense to, will lay a deaf ear to sensible & scientific explanations. He definitely has a different agenda or is unstable...

[@andromedach]

Well it is very early to speculate and we need to be careful given the hedging Chris A has made about how weight and tires affect the mileage. The efficiency numbers of Aptera are not possible to determine because Aptera has not provided information on the production vehicles. We do not know its actual weight, we do not know the actual cD, and we do not know the efficiency of the motors. What we do know is what tires they did purchase fifty of but even then we don't know if this will be the tire on production vehicles. Those tires are from PT Hankook out of Indonesia and the specs are 195 50R16H,04,H735. We actually do not know the cD of Gamma because even though Aptera made a big deal out of going to the wind tunnel Chris and Steve both refused to provide the results and would not even state if it confirmed the numbers they expected, all they could claim is being one the most efficient measured. In other words, this is all fantasy because there are too many unknowns so using the fictional numbers we have all we can get are guesses.

[@RomanChaar]

How dare you use well known formulas to state your claims. I'm with the guy on twitter who uses girl math to make assumptions. #womencandomathtoo #it'sajoke #dontcancelme #ineedtofeedmyfamily

[@peterbroderson6080]

My bet is no major production and bankrupt. Advertised 1000 range yet only 45 miles on a days sunlight charge? Electric motor overheats going up a small hill? Seems like "Fraud" to me!

[@DrTeeHenry]

You are cherry-picking stuff that by themselves are true -- sort of -- but don't relate to each other. The 1000-mile version of the vehicle will have a 100+ kWh battery; "sunlight" charge is gravy on top of that. The overhyped wheel motor overheating happened when the cooling was disconnected. I bet your ICE might overheat if the radiator hoses were disconnected.

[@barnabasseadog7660]

Where is your bet? My bet is on the leaderboard. That's right, real money on the table. success or failure, I'm good with my bet. So your just another naysayer spewing negative vibes, eh. thanks for the motivation.

[@garywozniak7742]

It is a battery EV that can be plug-in charged that has 700 watts of solar panels that can provide up to 40 miles of charge per day.

[@nathanahubbard1975]

I don't totally disagree with you, as it's still up in the air whether this thing will happen. But that overheating was with a prototype that didn't have cooling connected to the motors yet, so that's kind of a BS issue. However, I can see why they might be having cooling issues, given the lack of a traditional radiator.

[@jeffcarlton3590]

@@DrTeeHenry And EV drivers pass by overheated ICE cars, stuck in pullovers, on significant climbs all the time.