Comment by throwaway2037
18 hours ago
> Towing with an EV is terrible.
As I understand, electric motors deliver instant maximum torque. Isn't that advantageous for towing? You can get a good list of pros and cons from an LLM with a prompt like this: "towing with electric motor vs ice engine".
What is your opinion on the upcoming Tesla Semi? I expect that it will be successful, useful, and efficient.
Nobody expects an impressive 1/4 mile time from a vehicle towing a trailer. That's not what makes EVs bad at towing.
My towing-capable gas vehicle sees at worst a 30% decrease in range from towing my camping trailer, and my towing-capable diesel vehicle sees closer to a 10% decrease in range.
A while back, I read a comment on here from someone who lived in a trailer full-time as a digital nomad. They were also dedicated to driving an EV. They towed their small trailer with their Model Y. I grant you, the Model Y is not optimized for towing the way that the Cybertruck (ostensibly) is, but they described the process of travelling between Grand Junction, Colorado, and Moab, Utah, a distance just over 110 miles. With the trailer, they had to drive to Cisco, about halfway in between, drop the trailer, drive back to Grand Junction, recharge fully, drive back again, pick up the trailer, and drive the remaining 60 or so miles to Moab, where they could recharge again. Because without the trailer, they could drive the entire 1-way distance 3 times over without recharging. With the trailer, they could not make the whole trip once.
That is pretty bad. Probably a combination of the smaller battery, and a very non-aerodynamic trailer. Of course, an ICE truck could do it without too much trouble, but that's largely because most tow-focused ICE vehicles are wildly inefficient compared to EVs and are discarding lots of unused capacity every time you drive them without towing near maximum load. Not a big deal when diesel is cheap, but now, less so.
If you think about how much excess power your diesel is wasting when you aren't hauling its kinda crazy. When you changed the total weight, and thus total energy required in the system, 50-70%, you only started using 10% more energy.
I remember my family driving long distances in a 1980s VW Diesel, we could barely climb hills but we got 50mpg.
It is reductive to say it is terrible. The issue is that the current range we are putting in trucks, adjusted for the range loss from towing a large trailer, is insufficient.
The Tesla Semi proves that this is the issue: with an extremely large battery and high-speed charging, the Semi solves these problems.
A regular truck that can TOW 300 miles would certainly not be "terrible for towing."
> A regular truck that can TOW 300 miles would certainly not be "terrible for towing."
Agreed. A fairly typical gas half-ton gets 300 miles from a tank. If an EV can get that distance and recharge in like half an hour it would be a pretty great truck.
It's not hard to run the number and see how likely it is (spoiler alert: not very).
The first easy number is the sheer amount of energy, diesel has an energy density of 10.7kWh/L, so a 30gal tank holds 1460kWh. By comparison a silverado EV (probably the best currently available EV tower short of a semi) has a 215kWh battery.
The second more complicated number and why diesel is so good at towing (and other high-power applications) is that diesel gets more efficient when loaded, by a factor of 2-ish: an unloaded diesel might only use ~20% of the fuel it burns to actually move stuff, or on a 30gal you get around 300kWh out of your 1460kWh tank, but that will climb to 35~40% as the load increases if kept in the efficiency range, so towing you might have 500~550kWh out of 1460kWh available to actually move your load.
There's no such thing on an EV, there's some variation but load isn't really a factor, pretty much just the band, so your Silverado gets 205kWh usable at the wheels unloaded and the same loaded. Therefore all the towing losses (rolling resistance and drag) come straight out of your range.
And short of a breakthrough on batteries it's difficult to add more battery capacity, the battery already accounts for a third of a silverado's weight and a significant fraction of its internal volume. Getting a 500kWh battery in a truck is currently impossible: that's the sort of capacity you find on semis (european EV semis cluster around 550~650).
And then of course you have the charge concern, charging a 500kWh battery in half an hour requires a megawatt charger running at more than 1MW, and the ability to ingest that in your pack (on 800V battery tech that's 1250 amps, which is within MCS specs but the vehicle side is pretty damn rough).
They provided a concrete example: Trying to charge when a trailer is attached.
> As I understand, electric motors deliver instant maximum torque. Isn't that advantageous for towing?
Your understanding is not wrong, but quantity of torque is a minor piece of what matters, so that doesn't move the needle.
Towing lowers the range of an EV by so much that it becomes nearly useless. This is much more important with an EV than an ICE, because EV charging is less available and takes much longer.
It's understandable that you might not fully understand the magnitude of the pros and cons from your LLM prompt, those sorts of responses usually assume certain levels of experience and familiarity with the topic. It'll make more sense when you get older!
Towing for traveling, you mean. Around town, a Lightning with a big utility trailer is still good for over 100 miles, and that meets the use case for a lot of small businesses that need to tow. We get a bunch of them over on the Lightning forum. They love the truck, and they love how inexpensive and convenient it is. There was much wailing and gnashing of teeth (and a scramble to find funds to quickly fill out their fleet) when Ford announced the cancellation.
> quantity of torque is a minor piece of what matters, so that doesn't move the needle
I know of approximately nobody who thinks this, who actually tows anything meaningful. Somethning like a 6.2 naturally aspirated Ford V8 in an F250 is a chore, it's loud, works very hard, goes nowhere with any urgency. This is why people love diesels -- torque. And an EV takes that to the next level. The towing is sublime.
Yes, we need bigger batteries though so people can do long distance road trips with travel trailers. That niche isn't a great use case today.
The downside of electric motors for towing is that they require electricity.
And towing requires a lot of electricity. How do you bring enough electrons?
The towee could carry an additional battery. Probably not hard to link it with a cable to the tower.
RV trailers like that are coming to market, seems like a good solution. e.g.
https://pebblelife.com/
https://www.evotrex.com/
https://www.aboardrv.com/
An additional perk for these is you now have a large battery to power appliances in the trailer.