Tesla Model X tows Airstream

Tysonthedestroyer

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ajdelange

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Not quite apples to oranges but at this point I’ll take any perspective about towing capabilities. Here’s an article from Inside EVs that says what you tow can make a 27% difference in efficiency and thus range https://insideevs.com/news/448466/video-tesla-model-x-towing-airstream-bambi/
Yes, of course it can. People are always asking about the CT's towing characteristics. What they should be asking about is the load's towing characteristics. A CT driven on level terrain in traffic where the speed limit is 50 is going to pull about 495 Wh from the battery for each mile driven. About 40 W will be lost in the drive train, about 26 to slip 88 to rolling resistance and about 358.5 to drag. Thus drag is the biggest consumer (74.2% of battery usage). That's because the CT has regenerative braking and the driver, if he's a little careful, will never use the brake.

Now supposing he tows a trailer that is the same weight at the CT and has the same drag characteristics. It's loads will be the same except that a towed vehicle had no drive train losses and no slip losses except when it is braking which it must do because it has no motors or battery to collect regen energy. Thus we would knock off the slip loss and drive train loss but must add a brake loss of 160 Wh/mi for a total of 588 Wh/mi to tow the trailer. Note that the drag is still the largest load but now only 60.9% of the total. Thus range of the combination will be 495/(495 + 588) = 45.7% of what the vehicle could do without the trailer.

Now if we could reduce the drag by 27% we could save 0.27*358.5 = 96.8 Wh/mi which we would deduct from the trailer load giving a range ratio of 495/(495 + 588 - 96.8) = 50.2% that is we would be able to go 4% further. Every little bit helps.

Please note that all these numbers are based on assumptions about the CT that may not pertain in fact when the trucks roll out. Thus they are intended to be representative of what you might see rather than predictions of what you will see.
 

ldjessee

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I hope companies realize this and come up with trailer designs to be no wider than the CyberTruck when towed and fit into the CyberTruck's wake and try to minimize the drag and wake that it (the trailer) creates.
 

ajdelange

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Yes, I expect they are very well aware of this. It is really no different than the case with an ICE tow vehicle except that it has a brake load and the BEV doesn't.
 
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Owner13669

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At highway speeds, aerodynamics may mean more than weight. At slower speeds weight will matter more. For instance a small light weight non aerodynamic trailer may cost more to tow than say, a “Bullet” that is much longer and heavier. If you are towing at 65mph.
 


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OneLapper

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This weekend I co-drove my buddies 2000 Ford Excursion with the diesel. We towed an empty 7500 gvw dual axle open deck trailer at 75 mph for 400 miles non-stop, and got 11.45 mpg.

My buddy purchased a 2006 Kubuta L39 loader backhoe, 7000 lbs, plus a grapple bucket and two extra hoe buckets, so let's say it was 7500 lbs at a minimum.

On the return trip we drove 60 mph (the trailer was over weight, the hubs were running hot, and I'm pretty sure it had a couple broken brake shoe retaining springs). We got 12.5 mpg on the way back!

I was surprised, actually. The Excursion aerodynamics are evidently really bad! Slowing down to 60 improved the mpg despite the added weight and drag of the tractor.
 

ajdelange

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I was surprised, actually. The Excursion aerodynamics are evidently really bad! Slowing down to 60 improved the mpg despite the added weight and drag of the tractor.
Keep in mind that the drag of the trailer and the tractor (the tow vehicle) is double at 75 mph relative to what it is at 60 and the mpg component attributable to drag is 156% higher. The influence of weight depends on whether you use the brake or not. If you don't, weight has little to do with it. If you drive a BEV to a mountain lookout and then back home and don't use the brake it doesn't much matter whether you have your anvil collection in the trunk or not.

Here are some representative numbers for a vehicle like a CT

5500 lbs Speed 50 to 20 Avg 41.6 mph, 0.0 ± 0.0 %grade,Wh/mi Total: 505.6 , Drive: 43.1 , Slip: 27.9, Drag: 358.5, Roll: 96.7, Gravity: 0.0, Inertial: 0.7, Regen. On , Brake 0.0

5500 lbs Speed 65 to 35 Avg 57.7 mph, 0.0 ± 0.0 %grade,Wh/mi Total: 751.2 , Drive: 50.4 , Slip: 31.0, Drag: 585.6, Roll: 96.7, Gravity: 0.0, Inertial: 0.4, Regen. On , Brake 0.0

6500 lbs Speed 65 to 35 Avg 57.7 mph, 0.0 ± 0.0 %grade,Wh/mi Total: 772.4 , Drive: 55.0 , Slip: 33.4, Drag: 585.6, Roll: 114.3, Gravity: 0.0, Inertial: 0.5, Regen. On , Brake 0.0

In comparing the first pair note that the increase in average speed from 41.6 to 57.7 (speed limit 50 mph in the first and 65 in the second) increased consumption from 506 WH/mi to 751 mostly through sharply increased drag and less through the increased slip and drive train losses required to overcome that drag. In comparing the second pair (same speed progile) adding 1000 lbs extra weight increased the consumption to 772 Wh/mi, a change of 21 Wh/mi because of increases in slip and rolling resistance losses.
 
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Gotorah

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Yes, of course it can. People are always asking about the CT's towing characteristics. What they should be asking about is the load's towing characteristics. A CT driven on level terrain in traffic where the speed limit is 50 is going to pull about 495 Wh from the battery for each mile driven. About 40 W will be lost in the drive train, about 26 to slip 88 to rolling resistance and about 358.5 to drag. Thus drag is the biggest consumer (74.2% of battery usage). That's because the CT has regenerative braking and the driver, if he's a little careful, will never use the brake.

Now supposing he tows a trailer that is the same weight at the CT and has the same drag characteristics. It's loads will be the same except that a towed vehicle had no drive train losses and no slip losses except when it is braking which it must do because it has no motors or battery to collect regen energy. Thus we would knock off the slip loss and drive train loss but must add a brake loss of 160 Wh/mi for a total of 588 Wh/mi to tow the trailer. Note that the drag is still the largest load but now only 60.9% of the total. Thus range of the combination will be 495/(495 + 588) = 45.7% of what the vehicle could do without the trailer.

Now if we could reduce the drag by 27% we could save 0.27*358.5 = 96.8 Wh/mi which we would deduct from the trailer load giving a range ratio of 495/(495 + 588 - 96.8) = 50.2% that is we would be able to go 4% further. Every little bit helps.

Please note that all these numbers are based on assumptions about the CT that may not pertain in fact when the trucks roll out. Thus they are intended to be representative of what you might see rather than predictions of what you will see.
I disagree with part of it. The load towed will push on the tow vehicle as they slow so the towed vehicle will be energizing the regen of the tow vehicle.. Exactly as if the Towed vehicle had no brakes. The only way your senario is possible is if the towed vehicle has 'surge' brakes instead of electric brakes that can and should be applied by the driver of the tow vehicle.
 

ajdelange

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The only way your senario is possible is if the towed vehicle has 'surge' brakes instead of electric brakes that can and should be applied by the driver of the tow vehicle.
I the trailer had no brakes then your objection would be valid and I guess you can still rent U-hauls that have no brakes in which case the tow vehicle would indeed recoup some of the trailer's inertial load. If the trailer is bigger than some size it is required that it be equipped with its own brakes. These rely on decelleration of the trailer itslef (surge) or on the decelleration of the towing vehicle through an accelerometer in the tow vehicle brake controller which sends a signal to he brakes in the trailer. In any case the trailer is braked by its friction brakes - not the tow vehicles dynamic brakes and the mass related (kinetic and potential) energies of the trailer wind up a heat dissipated by those brake. They are not recovered.
 


HaulingAss

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Yes, of course it can. People are always asking about the CT's towing characteristics. What they should be asking about is the load's towing characteristics. A CT driven on level terrain in traffic where the speed limit is 50 is going to pull about 495 Wh from the battery for each mile driven. About 40 W will be lost in the drive train, about 26 to slip 88 to rolling resistance and about 358.5 to drag. Thus drag is the biggest consumer (74.2% of battery usage). That's because the CT has regenerative braking and the driver, if he's a little careful, will never use the brake.

Now supposing he tows a trailer that is the same weight at the CT and has the same drag characteristics. It's loads will be the same except that a towed vehicle had no drive train losses and no slip losses except when it is braking which it must do because it has no motors or battery to collect regen energy. Thus we would knock off the slip loss and drive train loss but must add a brake loss of 160 Wh/mi for a total of 588 Wh/mi to tow the trailer. Note that the drag is still the largest load but now only 60.9% of the total. Thus range of the combination will be 495/(495 + 588) = 45.7% of what the vehicle could do without the trailer.

Now if we could reduce the drag by 27% we could save 0.27*358.5 = 96.8 Wh/mi which we would deduct from the trailer load giving a range ratio of 495/(495 + 588 - 96.8) = 50.2% that is we would be able to go 4% further. Every little bit helps.

Please note that all these numbers are based on assumptions about the CT that may not pertain in fact when the trucks roll out. Thus they are intended to be representative of what you might see rather than predictions of what you will see.
Your estimate of 358.5 Wh for aero drag at only 50 mph is far too high. There is no way it could be anything close to that. The Cybertruck is more aerodynamic than it looks and the automatic ride height suspension will help a lot in this respect.
 

ajdelange

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And what makes you think that? You'll have to do better than "..is more aerodynamic than it looks". The numbers I used are, of course, guesses and I hope conservative ones. I used Cd = 0.4, Af = 4 and STP air density . If you've got the real numbers tell us what they are.

358 is probably realistic as it results in a total of about 500 which is what ABRP, at least, assumes the total will be. Hope you are right, of course.
 

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Tesla Model X Winter Road Trip: Should We Buy An Airstream?





How far will the Model X travel in the winter? Is it worth it to invest in an Airstream?
Our friends Katie and Steve, hosts of the YouTube channel All Electric Family, live for family road trips and camping excursions. They spent years towing a massive travel trailer with a gas pickup truck. However, now, they have a Tesla Model X for their journeys, but sadly, they have to pull a smaller camper in order to have a decent amount of range.

A Little Background
In our pursuit of new and interesting EV-related content to share with you, we stumbled upon a neat YouTube channel called Trail Less Traveled. The only reason it appeared on our radar is that the family hosting the channel bought a Model X. There wasn't much EV content on the channel at the time, but we found the Tesla towing trips compelling.

There was so much interest in the YouTube channel once we started highlighting its videos, that Katie and Steve decided to change its name to All Electric Family. In so doing, they also changed the overall content to be more geared to EV owners, and especially those who travel and tow with their Teslas.

Latest Road Trip and the Airstream
Fast-forward to the present and All Electric Family loaded up the Model X to its maximum capacity of seven passengers. They hit the road, however, this time, rather than towing something, they're heading out to find something new to tow.

All Electric Family learned that they can achieve more range with their Model X if they invest in an Airstream, plus they'll have more room for their large family. To take things a step further, they're considering buying either a Tesla Cybertruck or Rivian R1T in the future. The thought is, an electric pickup truck married to an Airstream could be the perfect rig for their extensive travels.

They head from their home in Nebraska to Des Moines, Iowa on a cold winter day to check out the Airstream Flying Clouds. Should they buy it? Check out the fun video for the details. Then, leave All Electric Family your advice in the comment section below. Cybertruck, R1T, or stick with the Model X? Airstream?


SOURCE: INSIDEEVs
 

ldjessee

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Why not park within the lines? Would have taken less time than recording the shot of him talking about the charging rate...

Yes, no one was parked next to him, but still seems like a behavior that would best not to give example of a Tesla owner...
 
 




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