Towing Range

[Evoforce]

Having towed with my Tesla long distances, I would buy the biggest battery truck if you plan on having a tow vehicle or for resale value for others who may want to tow. Towing over 7 thousand pounds sometimes only gets a third of normal range.

My car acted like there was nothing behind me with exception of sucking hard on the electrons.

I was still getting better than 30 mpg equivalent at its worst.

 

[JBee]

I think the intention of the video was just to demostrate the amounts of energy involved in towing, regardless if it was sourced from batteries or fuel.

The fact remains that battery energy density is still less than fuel atm and that you can't expect an EV with limited battery energy density to perform beyond what it is has energy reserves for. That would be perpetual motion. (And your looking at the wrong Tesla for that!)

In regards to ICE efficiency forced induction motors are above 30% some enen 40%, with F1 engines peaking at 51% conversion efficiency. The amount of fuel eneefy converted, even through an ICE, still makes more kWh of useable energy available in a fuel tank.

This is not a hit on EVs, its just a energy capacity comparison. I think he says that just two-three times the energy density in batteries would result in EV's having better overall energy storage capacity. From then on theres no turning back really.

 

[ecarfan]

I’ve done the math as well. It takes an additional 400-700 Wh/mi to tow my ~6800 lb black rock 22BHS camper if I keep it under 60mph That is over what it takes to drive without the camper in tow. So if the CT is rated at 500 miles at say ~300 Wh/mi it will take 700-1000 Wh/mi pulling my camper. I’m betting 200 mile usable range between charges out of the tri motor. When I pull the camper with my LX570 I have about 200 miles between fill ups so you are pretty accurate in a range to range comparison. The problem is I have no superchargers within thousands of miles from me but do have gas stations and Jerry cans.

The 500 mile range Cybertruck will almost certainly be able to tow my 17 ft 2,000 lb trailer over 300 miles, and I’ll be pretty happy with that. ​

 

[coleAK]

The 500 mile range Cybertruck will almost certainly be able to tow my 17 ft 2,000 lb trailer over 300 miles, and I’ll be pretty happy with that. ​

I’ll be happy with 200 pulling my camper. Only one place I go (our fall caribou/goat/sheep hunt) where charging will be an issue. Almost every other place we regularly go now has 240/30 hook ups. Get there and plug in the truck and camper.

 

[Evoforce]

@ecarfan Hard to keep most campers to only 2000 pounds. My 6 x 12 cargo weighs 1200 lbs empty.

 

[coleAK]

Hard to keep most campers to only 2000 pounds. My 6 x 12 cargo weighs 1200 lbs empty.

I said above my camper is ~6800 lbs loaded.

 

[Evoforce]

@coleAK . I was responding to ecarfan. You do have a typo though.

 

[keeney]

He fails to point out that the system efficiency of an F150 is less than 20% (more than 80% of the energy in the gasoline ends up as waste heat; that's why pickups overheat all the time when towing uphill).

20% is about the average efficiency during daily driving. Under sustained operation at peak efficiency an ICE converts up closer to 1/3 of the energy into mechanical power out the driveshaft, 1/3 as wasted heat out the radiator, and surprisingly, 1/3 of the energy goes out the exhaust system as heat, exhaust gas pressure&flow, and sound. An ICE that needs to exert a sustained 150hp while towing something needs a 150hp radiator. Most light trucks have engines that can put out higher power for short bursts, but don't have radiators that can support sustained operation at maximum power. How often do you drive you truck with the gas peddle completely floored for hours? If you exceed the power capacity of your radiator, you are going to overheat.

 

[ecarfan]

@ecarfan Hard to keep most campers to only 2000 pounds. My 6 x 12 cargo weighs 1200 lbs empty.

Yes, my trailer is extremely light for its size (almost 18’ long). Dry weight when I took delivery was about 1,700 lbs. I’ve added a lot of battery capacity and some other options, and with water and other stuff it weighs about 2,200 when I start a trip.

The Alto F1743 trailer uses almost no steel parts and no wood: it has an aluminum frame, walls and roof of double layer aluminum with honeycomb plastic insulation inside, cabinets and inner walls are aluminum and composites. Only steel is in the axle, suspension, and at the tongue. Aluminum wheels. Full kitchen, queen bed, table for two, bathroom with toilet and shower.

It is also moderately aerodynamic. I have a lot of energy efficiency data on towing it with my X, and that is why I am confident that the tri motor Cybertruck would be able to tow it over 300 miles at 55mph on a dry, level road with no headwind.

That said, I’m going to wait for a smaller Cybertruck. I don’t want a tow vehicle that is 3 ft longer than my X. I would be happy with a Cybertruck with a single row of seating and a shorter bed. Whether Tesla will ever make such a vehicle I have no idea.

This render of an imaginary 5th wheel RV designed specifically for a Cybertruck is pretty cool Tesla Cybertruck will launch a disruption in the camper/trailer industry - Electrek

 

[jackbowers]

I’ve done the math as well. It takes an additional 400-700 Wh/mi to tow my ~6800 lb black rock 22BHS camper if I keep it under 60mph That is over what it takes to drive without the camper in tow. So if the CT is rated at 500 miles at say ~300 Wh/mi it will take 700-1000 Wh/mi pulling my camper. I’m betting 200 mile usable range between charges out of the tri motor. When I pull the camper with my LX570 I have about 200 miles between fill ups so you are pretty accurate in a range to range comparison. The problem is I have no superchargers within thousands of miles from me but do have gas stations and Jerry cans.

I'm assuming you're in Alaska, as that's the only place where Superchargers would be thousands of miles away. But you could always plug in at the RV parks, where a 50A outlet is good for about 125 towing miles after a 12-hour overnight charge.

 

[jackbowers]

20% is about the average efficiency during daily driving. Under sustained operation at peak efficiency an ICE converts up closer to 1/3 of the energy into mechanical power out the driveshaft, 1/3 as wasted heat out the radiator, and surprisingly, 1/3 of the energy goes out the exhaust system as heat, exhaust gas pressure&flow, and sound. An ICE that needs to exert a sustained 150hp while towing something needs a 150hp radiator. Most light trucks have engines that can put out higher power for short bursts, but don't have radiators that can support sustained operation at maximum power. How often do you drive you truck with the gas peddle completely floored for hours? If you exceed the power capacity of your radiator, you are going to overheat.

You might get 1/3 of the energy into mechanical power with a diesel engine, but there's no way that happens with a gasoline engine.

 

[jackbowers]

Additionally he assumes you will be pulling a 14,000 lb trailer. I'd like to see the numbers with a normal size trailer, maybe 5,000 lbs.

Actually his example was with a 5,000 lb trailer.

I have no issue with his energy calculations, which were spot on. But he mis-represents the situation with his energy density chart. The energy density of gasoline, if adjusted for engine efficiency losses, is five times lower. The energy density of batteries, if adjusted for inverter and motor efficiency losses in the Cybertruck is at most 20% lower. To reflect the situation accurately, the energy density bars on the gasoline side need to come down by a factor of four.

 

[geoffmanley]

Actually his example was with a 5,000 lb trailer.

I have no issue with his energy calculations, which were spot on. But he mis-represents the situation with his energy density chart. The energy density of gasoline, if adjusted for engine efficiency losses, is five times lower. The energy density of batteries, if adjusted for inverter and motor efficiency losses in the Cybertruck is at most 20% lower. To reflect the situation accurately, the energy density bars on the gasoline side need to come down by a factor of four.

He did for the Model X, but used 14k for the Cybertruck.

 

[keeney]

You might get 1/3 of the energy into mechanical power with a diesel engine, but there's no way that happens with a gasoline engine.

This was a general rule of thumb in medium-sized (water cooled) gas and diesel engines. I learned about it when I worked making software for an engine dyno lab at a company that makes turf care equipment. From the data I saw, it was pretty close. The key was to run the engine on a sustained basis in the most efficient portion of its curve. ICE's used in vehicles in city traffic don't spend much time in any one part of their curve - your average efficiency is going to be down closer to 20% as noted. But highway miles in the right gear, or a tractor cutting fairways all day at the most efficient RPM, you can hit 1/3 efficiency with modern gas engines.

 

[coleAK]

I'm assuming you're in Alaska, as that's the only place where Superchargers would be thousands of miles away. But you could always plug in at the RV parks, where a 50A outlet is good for about 125 towing miles after a 12-hour overnight charge.

Yep in Alaska. Closest supercharger is farther than Atlanta, GA to Los Angeles, CA. Very few campgrounds up here have 50a, 30a is more common. I’ve always thought it would be easy to get to a campground and plug in the truck and camper. The problem is very few campgrounds up here take reservations and many areas only have a few with power, 5 years ago I could get power hookups easily. But with as popular as Alaska has gotten its very difficult to be assured a spot with hookups. Campground are packed with $250k+ class A’s from all over the lower 48 that take up one spot for weeks. I guess what I’m saying it would suck to get to Seward and not be able to make it home until someone moved from a spot with power and I was standing there waiting on it. Tesla really needs to install superchargers in about 7 places up here, the intersections and the ends.

 

[msunderl]

I wouldn't count on a longer bed, Tesla is about minimal options to keep costs down. I can see some people modifying the sides of the bed to remove the slant back of the toneau cover

Modifying the sides of the bed would risk the structural integrity of the entire truck. Not an option!

 

[jackbowers]

Yep in Alaska. Closest supercharger is farther than Atlanta, GA to Los Angeles, CA. Very few campgrounds up here have 50a, 30a is more common. I’ve always thought it would be easy to get to a campground and plug in the truck and camper. The problem is very few campgrounds up here take reservations and many areas only have a few with power, 5 years ago I could get power hookups easily. But with as popular as Alaska has gotten its very difficult to be assured a spot with hookups. Campground are packed with $250k+ class A’s from all over the lower 48 that take up one spot for weeks. I guess what I’m saying it would suck to get to Seward and not be able to make it home until someone moved from a spot with power and I was standing there waiting on it. Tesla really needs to install superchargers in about 7 places up here, the intersections and the ends.

When Guy Hall drove his Model S to Alaska I made him an 80' extension cord that plugs into electric dryer outlets. At 6 kW it's not as good as a 14-50 outlet, but would still provide about 75 towing miles with an overnight charge.

 

[ALSET YXES]

Energy Density....

All consumer vehicles are bad at towing...

 

[Swampgator]

Towing range will be 30-50% less depending upon weight and Aero. This is no different than an ICE truck. Not sure why so many act like this is a problem unique to BEV?