bratte
New Reader
1/31/23 7:05 p.m.
I think a big improvement in EV towing will come with the arrival of EV powered trailers. A single axle could be powered to provide assistance to the tow vehicle, utilizing a large (100 kW) battery mounted in the trailer. The battery could be charged while the trailer is not in use, and ready to go when needed. The control of the EV assistance could be handled with a combination of the trailer brake control signal, load cell in the hitch, and an on board accelerometer, like a modern version of a surge brake but in reverse.
For some perspective, one year ago I traded in my 2019 Miata RF Club on a 2022 Porsche Taycan. I've put 16,000 miles on it in that year, and I couldn't be happier. My commute is 50 miles round trip, 4 days a week. I charge primarily at home on a Level 2 charger. I have free Electrify America charging for 3 years, which I have used only a handful of times. I never had any issues charging with the 350 kW stations.
We still retain our ICE SUV for towing the Miata race car in its enclosed trailer to the track. Once things turn the corner on towing range, I predict we will be a two EV household.
bratte said:
I think a big improvement in EV towing will come with the arrival of EV powered trailers. A single axle could be powered to provide assistance to the tow vehicle, utilizing a large (100 kW) battery mounted in the trailer. The battery could be charged while the trailer is not in use, and ready to go when needed.
That's bigger than a Model 3 battery, which costs $15K and weighs over a thousand pounds. I don't think that's really feasible for most trailers.
I nominate J.G. for Best Discussion-Generating Road Test Report of the Year.
codrus (Forum Supporter) said:
bratte said:
I think a big improvement in EV towing will come with the arrival of EV powered trailers. A single axle could be powered to provide assistance to the tow vehicle, utilizing a large (100 kW) battery mounted in the trailer. The battery could be charged while the trailer is not in use, and ready to go when needed.
That's bigger than a Model 3 battery, which costs $15K and weighs over a thousand pounds. I don't think that's really feasible for most trailers.
I mean it depends on your definition of feasible. We have an enclosed trailer rated for 10k that I'm not sure we've ever had past 7.5k total. Plenty of room for 1500lbs of motor and batteries there. Probably the bigger issues are space, both fitting the motor without raising the floor and the fact that you'd have to split the battery up a bunch to keep the weight distribution reasonable and fit amongst the existing trailer structure.
RV trailers have high floors and even with all the stuff under it there's still usually a fair amount of space left. Could fill out the bottom with batteries (and probably slightly improve aerodynamics at the same time) but they tend to be more overloaded and/or not built as strong to begin with, so weight might be the biggest issue there.
Don't forget to account for any temperature management hardware that battery might need. Oh, and some way for the two vehicles to communicate which implies some sort of standard protocol or a marque-specific trailer. Handing could get interesting if the trailer starts driving the tow vehicle too hard. Cost is a factor as well, but that's a moving target. It's going to be a while before 100 kWh of battery is cheap, though.
I don't think powered trailers are likely to be a good option. I think we just have to accept that towing takes a lot of energy and there is no magic bullet to "fix" that. We're used to paying for that energy with the cost of fuel. With EVs, that cost moves more towards paying with time. Planning an EV towing trip will be different than planning an ICE towing trip. Not impossible, different. Maybe you nap more and stretch out your day. Maybe you don't try to eat a Big Mac while driving, but sit down instead.
Or maybe you find some other solution, such as accepting the compromises of running an ICE instead of an EV when you're not towing so you have the ICE when you do tow. The alternative is to accept the compromises of towing with an EV so you can drive an EV when you're not.
dps214 said:
I mean it depends on your definition of feasible. We have an enclosed trailer rated for 10k that I'm not sure we've ever had past 7.5k total. Plenty of room for 1500lbs of motor and batteries there. Probably the bigger issues are space, both fitting the motor without raising the floor and the fact that you'd have to split the battery up a bunch to keep the weight distribution reasonable and fit amongst the existing trailer structure.
A lot of people overload their trailers as it is, but as Keith says the biggest issue is cost. It's proposing putting a model 3 drivetrain into the trailer, so figure $15K for the battery alone and probably $25K once you add motors, controllers, cooling, etc. All for something that you would only use while towing? Maybe you could sell that to people buying $200K luxury RV trailers, but I doubt you'd get many takers on this forum. :)
Trailer aerodynamics are not likely to change much either. Getting complex shapes like cars have down to reasonable price levels requires a lot of expensive tooling, meaning it really only works for large volume products. Trailers are generally built by small vendors making a few at a time, so they're built out of cheap sheet materials and that makes them boxes on wheels.
I've seen ads for a camper trailer that included a 'pretty big' battery that could be connected to the EV tow vehicle. Sorry I don't have more details, but does a battery in the trailer as a range extender for the EV sound like it would work?
Danny Shields (Forum Supporter) said:
I nominate J.G. for Best Discussion-Generating Road Test Report of the Year.
Technically the story came out in 2022, so I think we missed award season.
STM317
PowerDork
2/1/23 11:03 a.m.
Towing (and most heavy, sustained work) is a duty cycle where we can't simply "add more battery" to fix the issue because that battery is both costly and super heavy. There's not a business case for it, and even if there were, you're talking about adding thousands of lbs to the trailer which means the tow pig has to work harder, and the load has to be lighter.
There are mountains of money being dumped into hydrogen as a diesel replacement for these types of duty cycles without the range/charging time issues of batteries. But we're still a couple of years from that being an option on the market, and even more years from the infrastructure being in place to support it (at least in North America).
In reply to STM317 :
It's going to be a while before the hydrogen plan separates itself from the train plan. Until there's even a little bit of infrastructure, hydrogen trucks are going to be limited to runs between specific points - and trains already do that very well.
In reply to JG Pasterjak :
First let me thank you for your complete and though report. Well done.
Early release Ford showed an in bed generator. Whatever happened to that? A really decent one would be less than 1000 pounds. Could it be plugged in while driving to extend range from 100 miles to 200 or more?
Now me,
The lightening has 2 problems I can't overcome. First it won't fit. My current 150 regular cab is tight. The crew cab version would be condemned to remain outside in the arctic tundra.Temps can drop to -40f and then there is the subject of snow. I cleaned 8 inches off the last time and we've had more than 24 inches in a single storm. ( on Halloween). So even with electrons flowing into it, charging it and keeping it warm. There is some additional work involved in outside storage.
Second? I'm 75, semi retired and made my last payment on the current low mileage truck. Taking on another $85,000 debt? ( Prices will come down soon). Just ain't happening.
If I did win the lottery, I could make it work for me. Elkhart lake is 355 miles away. 100 mile range gets me an hour+ into Wisconsin. Nice time for breakfast. Stretch the legs. Back in the truck for a couple of hours. Next stop, Sight see while charging. Maybe read a book. ( retired remember? I left a day early). Rinse and repeat. Only one charge stop up to Brainerd.
My advantage is I won't bring a garage with me. The race car is going to be 2000 pounds, the trailer 500. Tools and spares? Maybe 500# so I'd do better than quoted range. As if it matters.
STM317
PowerDork
2/1/23 2:54 p.m.
In reply to Keith Tanner :
I get what you're saying, but trucks can use the expansive network of roads that we have, while trains are limited to a much smaller and less flexible network of rail lines.
Infrastructure will take time. And there's no guarantee that it happens at all on any large scale in the US.
New tech (be it hydrogen, battery trucks, alternative fuels, etc) needs to have customer interest (demand) and government backing to establish a foot hold. In North America, there's currently only one of those for hydrogen at best. However, in India, East Asia, and Europe there's more of both. That's where hydrogen is likely to be accepted initially. IF it's shown to be viable there, then I'd guess that it's more likely to get the support it needs in the US to have a viable business case.
In reply to Renomiata :
Two points you missed. One vehicles sit in the garage at night when demand is at its lowest, the battery gets charged. So instead of additional drainage it will level out demand.
plus states that are subsidizing solar panels etc (20) won't need new power generating plants During the day home use is down while industrial/office use is at a maximum draw. Plus power plants aren't put where the energy is used they are put out of the way. It's called transit losses but if a solar panel is generating excess energy there isn't much transit loss because the excess is used right nearby.
My point is? Things will be better in the future especially if your politicians care more about the people they represent than big industry like the utilities
rob_lewis said:
I'm curious, has anyone run a Lightning to empty to see what the actual mileage is? I'm sure the gauge on the dash is really accurate, but how much fudge factor is built into it? MPG gauges, while better, aren't perfect and can be fooled by driving styles. Granted, going to "no charge" would mean you'd need a tow truck to get you to a charging station as opposed to grabbing a fuel jug like in an ICE, but it would still be interesting to know. Is 10% charge left really only 10 miles or is it really 10 miles plus a fudge factor of another 30?
I really like the Lightning for what it offers, especially if I was buying one for weekend warrior home improvement runs and daily driving. Which would probably be what 90% or more of most of them would be used for. It just seems like for long hauls and towing, they're not quite there yet. Both as a result of battery density and, potentially, high level charging sites. I figure, however, that will be less and less the case over the next couple of years. Especially in the charging site aspect.
EV's are still in a bit of a tough situation, but one they can, and are, getting through. It's the chicken and the egg scenario. More EV's will create more places offering charging stations and more charging stations will make people more likely to move to EV's. I think we're on the cusp of it and if EV prices continue to drop, you'll start seeing an exponential growth in EV sales.
-Rob
I thought Ford had that figured out? Pre-release they showed a generator in the Fords truck bed.