Engineering Explained: F-150 better than Cybertruck for towing duty (over distance)

[ajdelange]

..an extra 200 lbs of battery is not a big deal which adds 100 KWH pack easy.

No, 200 lbs is not a big deal but with the best lithium specific energy I am aware of (265 Wh/kg) its only going to give you 265*200/2.2
= 24090.9 Wh, For 100 kWh you'd need at least 800 lbs plus the weight of the case, coolant loops, BMS etc.

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[Cyber_Dav]

No, 200 lbs is not a big deal but with the best lithium specific energy I am aware of (265 Wh/kg) its only going to give you 265*200/2.2
= 24090.9 Wh, For 100 kWh you'd need at least 800 lbs plus the weight of the case, coolant loops, BMS etc.

Not to mention price... Powerwalls are up to 10 grand installed. What's a realistic price for a 100kWh pack, including as mentioned new wiring, cooling and BMS?

I do admit many would buy it as a $40,000 option, but it won't go mainstream at that price point.

 

[ajdelange]

I suppose you could use the Power Wall as a model. Those are 13 kW each so you'd need 8 for 100 kWh. So 8 times the price of the powerwall less say 10% for the common parts.

 

[Garden_Aum]

If you had 8 Powerwall 3 models the cost would be approximately $52K and the weight would be approximately 2,150 lb without the additional connections. So, in theory, there might be a possibility of having bolt on range extenders for the CT located in the cyber vault. My concern would be battery conditioning. I believe the bolt on option would require some sort of active heating and cooling option for the batteries so that optimal charge and discharge could happen when connected to fast charging infrastructure.
Thoughts?

 

[ajdelange]

Each Powerwall has a BMS which has to include close tempereature control. I don't know whether it is active or passive. The fellow that put the old S battery into his home made trailer heated it actively but cooled it passively, But I don't think he's tested it in Death Valley in the summer yet. Rough rule of thumb for cooling is 1 HP per ton (12,000 BTU/h).

 

[CarsBarsMars]

In what way does the fact that the vehicle is electric make things any different from what they would be with an ICE vehicle?

It's the refueling in the kind of places people take vacation trailers. There is nothing predictable about cross country travel , I once drove through a tornado strike across the expressway just minutes after it happened as an example....within half an hour it was a parking lot that lasted all day.

My personal thing is that I am working when I tow a trailer, so an ICE that I can refuel quickly keeps me working without keeping me thinking about battery planning.

I would be happy to tow with a CT if I were running out to pick up appliances or materials and coming straight back. I just dont think it's a wise choice for OTR towing the 10,000 pound trailer,which seems to be the preffered question when I see towing as a topic.

For reference, there are no superchargers around me, and the ones I have seen are attached to parking spaces....you cant use parking spaces with a trailer, you're limited by the "I can get in but can I get out" rule of parking lots. With a really long trailer it's best not to wander too far from the interstate, not pull into fast food parking lots, etc. You get used to parking it close to the gas station and then walking to the restaurants you want to visit on the break.

I plan to use mine mainly as a family/weekend vehicle not as a work vehicle as it also violates my "never pay more than 10k for a work truck" rule. And the "never use a truck you like as a work vehicle because it'll get ruined". I'll do some light camping in parks with electric service, etc, I just would not include a CT in any sort of large Travel Trailer or Hvy Duty work trailer capacity.

 

[CarsBarsMars]

If you had 8 Powerwall 3 models the cost would be approximately $52K and the weight would be approximately 2,150 lb without the additional connections. So, in theory, there might be a possibility of having bolt on range extenders for the CT located in the cyber vault. My concern would be battery conditioning. I believe the bolt on option would require some sort of active heating and cooling option for the batteries so that optimal charge and discharge could happen when connected to fast charging infrastructure.
Thoughts?

Park the extra batteries in a trailer under the floor. That way when you hook up your CT to your trailer you get twice the battery to offset the extra weight.

 

[Saskateam]

Tesla will be looking at how to charge the semi without unhooking. The CT may be able to take advantage of the semi charging network.

 

[CarsBarsMars]

Tesla will be looking at how to charge the semi without unhooking. The CT may be able to take advantage of the semi charging network.

Seems like a lot of work to make the CT a little better at something that it's going to struggle to be good at.

With respect to the Semi, if they're self driving and set up like a network, it would be easy to have a charged tractor waiting for the trailer to be dropped off by a discharged tractor.

 

[ajdelange]

Tesla will be looking at how to charge the semi without unhooking. The CT may be able to take advantage of the semi charging network.

Tesla's current policy is to not allow vehicles in commercial service to use the SC network. This implies that, for example, a taxi or delivery company using Tesla cars must arrange for charging elsewhere such as through chargers located at its dispatch or service garage. It is reasonable to assume the same restriction will be placed on the Semi. But the Semi is different. It has to go out on the road to be useful and so something like a SC network for these beasts will be necessary. Logic says that the stations would be placed at truck stops. I think we can be sure that they will be arranged more like the fuel pumps at truck stops that the pedestals at Super Charger stations.

We don't hear much about the Semi these days. Wonder if it will ever be sold.

 

[Rthardison]

This is beyond my elementary physics understanding, but here's an engineer's perspective of towing with an EV pickup versus an ICE pickup. Seems like the conclusion is that an ICE pickup has a range advantage even though it's less efficient at towing compared to an EV. But the gap will get closer as battery capacity in EVs go up.

It would be interesting to compare the cost of each scenario.

 

[Dids]

In my current tacoma truck I get about 300 miles between fill up. It my future CT I will get about 300 miles. If I hook up the same trailer to either truck it will drag them by the same amount. Why do people keep saying I will have longer range in my ice truck. What they really mean is it will take more time in CT because of recharge time. Since electricity is more economical per mile than gas it will be cheaper in CT to tow. Then the question just becomes do I save enough money using electricity that the additional time is worth it. 300 miles $50 in gas($3 /gallon)vs 300 miles $30 in electric ( .25 / kWh) I save $20 so if I drive 1 additional hour in CT due to charging I just paid myself $25 because that $20 is after taxes. These numbers are for Massachusetts so $25 for an hour isnt very good but I spend most of my day goofing off anyway so its hella better than nothing.

 

[Keeney]

In my current tacoma truck I get about 300 miles between fill up. It my future CT I will get about 300 miles. If I hook up the same trailer to either truck it will drag them by the same amount. Why do people keep saying I will have longer range in my ice truck. ?

You are correct - the trailer has the same drag either way. But because the ICE truck is less aerodynamic to start with, when the trailer drag is added to something that already has a lot of drag, its less drastic of a change.

For example, say the ICE truck has a drag of 6 units. And the CT is 2 units. To get the same range, the ICE truck needs 3x the total energy capacity (total output at the wheel after all efficiency losses). Say that they both have the energy storage capacity needed to get 300 mile range without a trailer. Then say the trailer adds 6 more units of drag. So the ICE+Trailer is going to have 12 total drag and the CT+Trailer = 8 units. The ICE range is only going to go down by the ratio of 6/12 (or 1/2) to 150 miles. But the CT is going to go down by a ratio of 2/8 (or 1/4) which is 75 miles.

 

[bfdog]

maybe switch to tent, hotel, or cabin camping if CT is your thing. At least campgrounds have big plugs though..

I LOVED THAT VIDEO. Very informative. I tow heavy locally with 60 mile round trips. Instead of spending 50 bucks filling up I would like to spend 25 on electricity. Or less. I live in the hill country and will like the massive torque when pulling up these hills. Also I’d like to use regen braking advantages when towing.

moral to that video is like digital cameras. Back in the day you could take 30 pictures on AA batteries at 1.2 mp. Now I take 2500 pictures at 60 mp with my camera, We simply don’t have energy density in battery packs yet, but a big portable battery could help. A tow aid with a. Battery pack that allows 5th. Wheel towing. Somebody posted a link before.

i wish he would talk about in the video electrical energy generation efficiency, transmission efficiency, the difference in pollution, and the cost of electric fill up versus ICE. And what each trip to the mountains does to the environment. Towing 14k fifth wheels Is pretty fancy. It’s a first world white people problem as they say`-how to get my 14k minimalist kit 100 miles away and 1 mile up. But I totally get it.

 

[Dids]

You are correct - the trailer has the same drag either way. But because the ICE truck is less aerodynamic to start with, when the trailer drag is added to something that already has a lot of drag, its less drastic of a change.

For example, say the ICE truck has a drag of 6 units. And the CT is 2 units. To get the same range, the ICE truck needs 3x the total energy capacity (total output at the wheel after all efficiency losses). Say that they both have the energy storage capacity needed to get 300 mile range without a trailer. Then say the trailer adds 6 more units of drag. So the ICE+Trailer is going to have 12 total drag and the CT+Trailer = 8 units. The ICE range is only going to go down by the ratio of 6/12 (or 1/2) to 150 miles. But the CT is going to go down by a ratio of 2/8 (or 1/4) which is 75 miles.

No. This is voodoo math. Let's take CT out of comparison and substitute it for a diesel identical to the gas ICE.... ( they both have unloaded range that is identical) Your drag ratios would be identical for both yet in the real world the diesel will still be magically chugging along after the gas has run out. That's because torque from the diesel means it's efficiency decreases less from identical load.

There is a reason trains use diesel and electric and that reason is torque. They are able to haul loads / distance.
Electric motors are torque monsters, they outperform diesel.
So what I'm trying to say that the range reduction will not be as drastic as people fear.