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"With the extra weight, a charge will only last about 60 miles, rather than the standard ~300 it normally gets"

A 5-fold difference?! Towing a trailer makes the Tesla use 5 times more energy per mile!? This can't be right... Author must have a trailer loaded with a literal ton of cargo.

Edit: a Tesla Model Y is 4200 lb. The trailer is about 3000 lb empty (thanks LukeShu), say worst case 4200 lb loaded with cargo, so at most the weight difference can account for a doubling of the energy per mile. It seems hard to believe drag alone can account for another 2.5x increase in energy per mile, which is why I think there must be even more cargo. If not, I guess for me this highlights how good the aerodynamic design of the Model Y must be. This also means the author could get a significant range increase simply by choosing a better trailer with a lower drag coefficient. Or my preference would actually be getting a vehicle designed for that lifestyle in the first place, an actual camper van. One could even use the comfortable driver seat as the office chair, instead of transporting an actual office chair. Swivel it toward your desk behind it and, bam!, instant office desk: https://www.thewaywardhome.com/wp-content/uploads/2022/12/Sw...



Also:

> Recently, I was hopping back and forth between Grand Junction, CO and Moab, UT—a distance of 113 miles. I had to go about halfway, stop, unhitch the trailer, then go back and charge the Tesla up again before finishing the trip. It makes travel days very slow.

I'm sorry. I could never be that committed to the ideology of EVs to do something that preposterous even once. The second I realized that was what would be needed, either the trailer idea would have to go, or the Tesla's being traded in for like, a Ford Ranger.


That sticks out to me too. You're already very constrained about where you can go because you need charging stations. But to then shrink that "only routes with chargers at least every 50 miles" wipes out huge portions of the US, or you have to resort to stupid hacks like the above.

And honestly, I'd be very wary about dropping my trailer in like Cisco or wherever. Its not quite the San Rafael Swell, but the Colorado Plateau is rather famously deserted. If my entire life was in that trailer, I'd really hesitate to drop it in a place that has signs that say "next services, 70 miles".

At what point do you accept that your EV ethos is incompatible with the rest of the lifestyle you want to lead? Either the lifestyle needs to change or the ethos does.


Well, EVs are still early products and it will take some time to develop additional charging infrastructure. I personally have an EV for short trips around town and a gas car for longer trips or whenever needed. I would not recommend an EV unless you’re passionate about them, or can afford a toy, or want a used second car for a daily commute that is under 50 miles total if you can charge at work or at home as needed. A used EV for daily commuting can cut costs and emissions which is cool. I think the average car consumer will still want to stick with a gas car for most likely the next decade as adoption progresses gradually in line with continual infrastructure and battery improvements as well.


Perhaps they could also put a gas/diesel generator on the trailer, and use that to charge the car when not driving


Or we applaud the author for his commitment to the ethos. Lesser men would give up and get an ICE, so the author's dedication to EVs is commendable.


Let’s not, maybe. This person is cramming a 4d tesseract into a 2D circle hole. There is very little to praise about this ethos, it’s simply more consumerism, not environmentalism.


Lesser men would stay in a normal house and not use energy to move it constantly.


And not travel the country openly during COVID...


Heaven forbid individuals use the right tool for the right job.

Meanwhile we fund governments and corporations to be careless about any ethos except profits.


The route from Grand Junction to Moab is an infamous decline. It's pretty trivial to believe the greatest inefficiency is drag. The second worst would be traffic.

I'm definitely surprised that they wouldn't recoup most of the energy loss through regenerative braking, though.


He would save himself so much money by going to ICE car, a reliable brand which requires minimal maintenance will save him so much money and he will be able to actually drive to somewhere with the trailer.

60 miles... with a brand new 40k car. Wauw


Well, he could get a Ford ev truck and make that commute in the spring and fall

https://youtu.be/76l6lJhrgbc?feature=shared


Maybe there’s a market opportunity for an EV trailer - something that has own batteries for extra distance, or even it’s own electric assist motors.


Airstream has a concept trailer called the eStream which has electric assist.


Fr just get a porche cayanne s plugin hybrid if you want an EV that can tow long distances


We got a very small, teardrop trailer as a gift from a relative a couple of years ago. It's awesome, but I was absolutely floored at how badly towing it killed our mileage in a Y. We went short distances so I wasn't too scientific about it, but I'd wager it cut our range in at _least_ half.

Our friend borrowed it to take a small Uhaul trailer to pick something up from family and had a similar experience. At one point he called us asking, cryptically, "how low was safe to plan to get to a charging station." Turns out he was on a longer stretch between chargers that he'd handled fine on the way out, but, like the author, ended up having to leave the Uhaul and come back for it on the way back.


Most of the energy from driving at highway speeds is coming from aerodynamic drag, and as you say, the Teslas are highly optimized, and the average camper trailer is not really at all. With a gas vehicle this isn't too big of a deal because you only use the camper a couple of times a year, and there are gas stations everywhere, and it only takes a few minutes to fill up.

This suggests to me that there's an emerging business in camper trailers designed for EVs. Make aerodynamics a priority (which also does increase costs and potentially make the living space a less useful shape). There are also trailers starting to emerge that have batteries in them. I've seen some where you can charge the car from the trailer's battery (not sure if they work while the car is moving though), and there are even a couple where the trailers wheels are driven, but I'm not sure how much of that you can really do and keep the vehicle stable.


Towing really is an EV use-case that is no where near ready for primetime. There's several Youtube channels that have spent time playing with it (JerryRigEverything, BigTruckBigRV), but it really is early days.

We have a 1 ton dually that pulls a 5th wheel when we camp. Yes, we're at the far end of the camping spectrum, but it's what we've evolved to over time, and it's finlly a safe combindation. There is nothing that approaches a diesel pickup for it's ability to haul cross country with relatively rapid refuelling, and many Campers go through an iterative process where their Tow vehicle isn't adequate to the trailer they were sold, they upgrade the two vehicle, then outgrow the trailer...rinse-repeat.

It's been said plenty of times before, but gas and diesel's biggest problem is that they're just so energy dense and easy to transfer.


Biggest problem in the sense of making them oh-so-hard-to-resist? Otherwise I would have thought their biggest problem is emissions (CO2, and particulates for diesels...)


It's that second runner up is massively less convenient...The reason why certain addictive drugs are so bad isn't how they make you feel, or what they do to your body friends and family, it's because they're damn hard to stop using.


Re: drag having such a large impact-- the aero wheels alone account for a 3% range improvement [1]. Everything about a tesla optimizes range, so it's probably extra-impacted by anything that doesn't (like a big trailer).

I also wonder if the regenerative braking is less efficient / engages less often when dealing with larger weight.

[1] https://www.caranddriver.com/news/a30169467/tesla-model-3s-a...


> I also wonder if the regenerative braking is less efficient / engages less often when dealing with larger weight

I'd def be interested to hear more if this is true, my gut tells me you should actually be able to get more energy from regenerative breaking, but could def see it not being set up for towing at all and sensing the extra weight falling back on traditional brakes earlier.


The problem with greater regenerative braking is that it leads to more abrupt deceleration. The car has to strike a balance.

I drive a Model S Plaid. My car’s maximum regenerative braking capability is 150kw. It is easily reached, immediately, when you let off the accelerator at highway speed, but more would not necessarily be better.


large trailers have their own braking system that bypasses most of the forces going through the hitch, so you use energy from the car to pull the trailer uphill but don't get much of it back when going downhill


The trailer itself is about 3000 lb. (2023 version of that trailer: https://forestriverinc.com/rvs/ozark/1530VBK/6564 IDK what model year OP's is). Plus lotsa added drag.


Frontal Area is an absolutely massive factor.

We have a 6x12 trailer that we’ve done a minimal RV conversion on. It rings in at 1300lbs empty. Maybe 1500 loaded. However, it’s 6.5 feet tall.

Towing that cuts our SUVs fuel economy from 25 mpg to 10 mpg at highway speeds. In the winter, we’ve had it drop as low as 6 mpg.


Some thoughts:

- aerodynamics make a huge difference. Even in a light trailer. Especially if it has a significant frontal area. That’s for sure.

- towing a trailer may reduce energy recovery from regenerative braking.

- when towing, power requirements on the motors and batteries may move them away from optimal efficiency and design points (that’s a guess).

- the model Y is probably not significantly more aerodynamic than comparable sized car models. But it’s a lot more aerodynamic than a trailer.


I have no experience with EVs, but one other thing to check would be the gearing on the Model Y. I know electric motors' torque curves are forgiving enough not to need more than 1-2 gears, but maybe that changes with a heavy load uphill.


Aerodynamics at play? Tesla is fairly good but any trailer is really bad which could lead to a much lower efficiency than anticipated? Also brakes might be half deployed on older trailers with bad tire geometry etc.


> I have a kitchen, a full bathroom with a shower, two beds, and even a whole office space inside the trailer.

With all that plus the extra drag, I'm not too surprised.


As a Tesla owner this makes sense. The cars are highly optimized to stock configuration. Doing any sort of extra load or mods quickly diminishes range.


Yes this is true. I once saw a TV show where they tested the VW ID (SUV type) with a normal caravan/trailer and they had over 50% less mileage.


Perhaps this YT video[1]? Range goes from 231 miles @ 60mph (best case) down to 100 miles @ 60mph when towing a small caravan.

[1]: https://youtu.be/mmQJUW-VyRY?t=1162


A literal ton of cargo in a trailer is nothing extraordinary. Did you ever lived on a farm?


ya but not when your tow rig is an EV SUV

a heavy duty diesel tow pig usually has an auxiliary fuel tank in the bed and can do 1000+ miles in one go.


Aerodynamics. It's possible for a trailer to be 5x less aerodynamic than a car.


If he’s dead set on an electric vehicle he could even get a VW ID Buz camper van.




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