Range reduction when towing.

[Crissa]

What I'm saying is that the major share of range loss is going to be drag.

The greater the difference between the drag while towing and the drag while not-towing the greater the range loss.

The Cybertruck will be more aerodynamically efficient than the Ford. This is a given.

The towing load is the same. (Because why choose to compare something different?)

Therefore, the Cybertruck will have the greater difference between not-towing and towing. Hence, the greater range loss.

And this will not matter because the Cybertruck will have greater range for less cost in the first place.

-Crissa

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[ajdelange]

"for a traditional truck, I know when I tow something heavy, my mpg reduces a lot. I think this should be same on cybertruck right?"

When we drive an EV we're vigilant about range. When we drive a liquid-fuel vehicle we don't much care, because we can refill at about every major corner. So that makes us think that when an EV pulls a trailer, it's mileage will drop more. But would not the trailer-pull range have a similar decrease with any power source?

The energy required to pull a trailer a unit distance is
E = V + T
in which V is the energy required to move the tractor a unit of distance and T is the energy required to pull the trailer one unit. The ratio

r = (V + T)/V = 1 + T/V

is a number by which one must multiply the consumption of the vehicle alone to get the total consumption. Obviously if V = T, IOW, if it takes an equal amount of energy to move the tractor and the trailer the total required is double that required for the tractor alone and range is halved. And so on.

The other aspect of this is that the energy used moving the tractor is V = U + W in which U is the useful energy extracted from the energy reservoir and W the unavoidable waste energy associated with U. This makes

r = 1 + T/(U + W) = 1 + (T/U)/(1 + W/U)

Note that as the energy required to move the trailer goes up relative to the the energy required to move the truck (U) the consumption factor goes up but as the waste energy W gets large the consumption factor goes down. Another way of putting this is that if most of the energy reservoir is to be wasted as heat the amount required to move the trailer doesn't have so much of an effect on range ratio.

 

[Dids]

The energy required to pull a trailer a unit distance is
E = V + T
in which V is the energy required to move the tractor a unit of distance and T is the energy required to pull the trailer one unit. The ratio

r = (V + T)/V = 1 + T/V

is a number by which one must multiply the consumption of the vehicle alone to get the total consumption. Obviously if V = T, IOW, if it takes an equal amount of energy to move the tractor and the trailer the total required is double that required for the tractor alone and range is halved. And so on.

The other aspect of this is that the energy used moving the tractor is V = U + W in which U is the useful energy extracted from the energy reservoir and W the unavoidable waste energy associated with U. This makes

r = 1 + T/(U + W) = 1 + (T/U)/(1 + W/U)

Note that as the energy required to move the trailer goes up relative to the the energy required to move the truck (U) the consumption factor goes up but as the waste energy W gets large the consumption factor goes down. Another way of putting this is that if most of the energy reservoir is to be wasted as heat the amount required to move the trailer doesn't have so much of an effect on range.

Nonsense.
What AJ is saying is that if you get 1 mpg then add a trailer and get .5 mpg it has less effect than if you get 10 mpg and add the trailer and get 5 mpg.

 

[Crissa]

Nonsense.
What AJ is saying is that if you get 1 mpg then add a trailer and get .5 mpg it has less effect than if you get 10 mpg and add the trailer and get 5 mpg.

No, but he doesn't explain it well.

If you get 5 mpg towing a trailer and 25 mpg not towing it... The second truck that starts out at 10 mpg will probably also get 5 mpg towing that same trailer.

There are other things which will intervene, but when it comes to electrics, those are small numbers.

If it takes X energy to pull the trailer, it mostly doesn't matter if it's truck Y or Z that pulls it; and if Y is otherwise more efficient than Z, the range loss for Y will be larger.

-Crissa

 

[Geo]

how much range reduces when I tow with cybertruck, let's say im towing 5000lb.

for a traditional truck, I know when I tow something heavy, my mpg reduces a lot. I think this should be same on cybertruck right? No, it will definitely be worse for the Cybertruck.

A Model X which we know will be more efficient than the Cybertruck has in fact been shown to suck at towing range, the Cybertruck will definitely be less efficient than the Model X
(at wh/mile consumption, ~ 270 wh/m vs ~ 320 wh/m) and therefore be worse still.

Do you want to use cybertruck to tow?
how much you tow usually?

Results below are with using the same trailer, but the F150 is carrying a 20% bigger load inside it.
(6000 lbs vs 5000 lbs)

To put it politely, This simple table shows the range reduction while towing is severe for an EV and will be worse for the Cybertruck. And the range reduction is worse than for an ICE vehicle !
Some people here are actually trying to obscure this simple fact, that is easily demonstrated.

Note : The Model X is more Aerodynamic than the Cybertruck, and it has a smaller frontal area.
: The range reduction when towing will be proportionally worse .

65.7 mile loop	Empty	Towing	Reduction in Range
Model X : weighs 5400	325 mile range	112 mile range	66 %
Towing 5000 lbs	19.3 Kwh to do 65.7 m	52.6 kwh to do 65.7 m
F150 Hybrid : Weighs 5200	700 m range (30 gal)	242 mile range	66 % towing 20% bigger load
Towing 6000 lbs	2.2 gal to do 65.7 m	8.18 gal to do 65.7 m
		~ 290 m range towing 5000 lbs	~ 58.5% towing 5000 lbs

For a load of 5000 lbs :

Model X = 112 mile range. Average 274 wh/m vs 924 wh/m while towing !!!!

F150 Hybrid = 290 mile range ( 2.6 x more range ).

These figures and the conclusions are facts beyond reproach.

Fact, Model X reduction in range from towing is a severe 66% !

Fact, Model X reduction in range from towing is more severe than F150 !

Fact, Model X is more aerodynamically efficient than F150, but drop in towing range is worse for Model X !

Fact, Model X is more aerodynamic than the Cybertruck !

Fact, that can be scientifically extrapolated is Cybertruck towing range will be more severely impacted than both the Model X and the F150 !

Simple plain facts, that Tesla Sycophants will try to hide from people.
You have been advised.

I look forward to towing with my Cybertruck a moderate load for a moderate distance, I have no doubt we will be seeing many many Youtube video's of Cybertruck's stranded out of juice !
What will be funny though, is will there be a group of same fools making repeated appearances

Note: Mach E has a great trip meter function which dissects how much of the energy is actually spent on propelling the car. How much to servicing the cabin needs, etc.
See top gear recent review, it showed of the total energy used, only 73% was used to propel the car. May want to take note about how much of the Cybertruck battery will be available for towing in the first place.

Jason : " Why Electric Vehicles Are Bad At Towing "


Watch how soon some Tesla Sycophant, happy to deceive people, suggest the TFL guys and Jason at Engineering Explained is wrong, without actually identifying a single fault !

 

[Crissa]

Geo, your statements are badly formatted and mathematically wrong.

-Crissa

 

[Dids]

Geo says that when you take a smaller frontal area model x and increase the frontal area by adding a trailer you get greater range reduction then if you use a larger frontal area vehicle and add the same trailer. This is true. The trailer adds more frontal area to the smaller vehicle than it adds to the larger vehicle. However this has nothing to do with Cybertruck which has the same frontal area as an f150. And he is conveniently forgetting that the larger vehicle is already range reduced before adding the trailer. In other words he is adding a greater load change to the model x than he is adding to the f150. If he took another similar SUV and compared it (porsche cayenne) I think he would quickly discover what a great towing vehicle model x is.
Crissa says because the Cybertruck is more aerodynamic than the f150 the increase frontal area added by the trailer , while identical affects the Cybertruck more because the change in aerodynamics is greater. True partially...
AJ says the more efficient a vehicle is the greater it is effected. Crissa agrees with this.

Meanwhile in the real world there is a way to test this, not by comparing apples to oranges.
A diesel rig vs a gas rig. Yes both experience the increase in load. If AJ is right the diesel should experience the increase more since the diesel has less waste heat than the gas. It doesn't. We can do math all day and in the end anyone that has used a diesel rig knows it is a better towing rig, better able to handle an increase in load and experiences less reduction in range.

But professor Dids how is that possible?
It is because there are 2 components to power, grasshopper. Force and time. Time is the same for both rigs so we can ignore it. What is different is force. The diesel rig produces more force and if you are stronger you can do more work while increasing your effort less.
But professor Dids by your calculation that would mean Cybertruck would have a lower range reduction than an F150.
I am not using math grasshopper, math is a precision language and we don't know enough parameters of Cybertruck yet so guessing at those parameters cause errors in math which quickly lead you astray.
So how should I know which will be better professor?
Always go with the highest force grasshopper! Now wax on, wax off.

 

[ajdelange]

Looking at r = 1 + T/(U + W) = 1 + (T/U)/(1 + W/U) it is clear that 1/(1 + W/U) = U/(W + U)= η, the effieciency so we can say that the range reduction ratio is 1 plus the efficiency time the ratio of the trailer load to the tractor load both in "useful" work units. But that's not really fair as T has to come from the fuel reservoir too.

What I frhink I am getting around to, or rather back to, is that the range reduction factor is simply 1 plus the ratio of trailer energy requirement per mile to vehicle energy requirement per mile both expressed in units of whatever form the energy is stored i.e. either kWh or gallons: r = 1 + T/V. As OEMs strive to keep T and V low, whatever the energy source, we can safely say that the range reduction factor is going to be about the same for BEVs as ICE vehicles and this tends to be confirmed by peoples' reported observations but we have to note that actual performance depends on so many factors that the reported experiences are not of that much value except for broad comparison. If you have a trailer which you have been towing behind an iCE truck and getting range reduction of 50% you will probably get roughly that with your CT.

We must also be aware that a range reduction factor of 2 means 800 goes down to 400 in a diesel with an 800 mile tank but 500 goes down to 250 in a CT with a 500 mile tank.

 

[Crissa]

Diesel has a different heat loss per power, so isn't equivalent. That's why I was comparing EV to EV.

-Crissa

 

[FutureBoy]

In the face of competing theories, someone needs to bring hard demonstrable evidence. Data collection with your calculations or it isn’t proven.

 

[Crissa]

We won't know until we have the trucks in hand, honestly.

But I'm pretty sure of my statement.

-Crissa

 

[Dids]

In the face of competing theories, someone needs to bring hard demonstrable evidence. Data collection with your calculations or it isn’t proven.

I just want everyone to remember that once they test it that it was me that said Cybertruck would experiance (((((less ))))) range loss than a gas or diesel rig of similar dimensions with the same trailer. ?????

 

[Crissa]

I just want everyone to remember that once they test it that it was me that said Cybertruck would experiance (((((less ))))) range loss than a gas or diesel rig of similar dimensions with the same trailer. ?????

For an aerodynamic or short height trailer, that may be true. It really depends on how it fits into the slipstream.

-Crissa

 

[Jhodgesatmb]

I haven’t said anything because I’ve been too lazy to work out the physics, and that is because I don’t care. I don’t care because I’ll deal with the range I get - I like the CT and I will definitely tow with it on occasion...whatever the range reduction is. There will definitely be range reduction and the physics calculations won’t change that, nor will they change my interest in the CT nor, I suspect, any of yours. At the end of the day I think that the Tesla truck will fare as well if not better at towing that any other EV truck.

 

[Diehard]

In the face of competing theories, someone needs to bring hard demonstrable evidence. Data collection with your calculations or it isn’t proven.

I have not read all the posts. Sorry if this is redundant but it is here just as a point of reference for extrapolation for CT performance:

https://www.edmunds.com/tesla/model...d-test/2016-tesla-model-x-tow-test-recap.html