QUESTION FOR THE BRAINIACS...

ExcessOilCo

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I have a CT on order and may be about to buy a Super C Class RV (mid size diesel chassis) that can tow 15,000 lbs. I want to boon dock so may be away from chargers and love CT as large onboard battery can provide power off grid to the RV.

Question: While towing can I 'activate' the CT so that towing behind the RV recharges CT batteries through very mild re-gen?

Ultimately may add enough PV to do the job but in the meantime I wonder.

Thanks in advance,

Jay





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android04

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I have a CT on order and may be about to buy a Super C Class RV (mid size diesel chassis) that can tow 15,000 lbs. I want to boon dock so may be away from chargers and love CT as large onboard battery can provide power off grid to the RV.

Question: While towing can I 'activate' the CT so that towing behind the RV recharges CT batteries through very mild re-gen?

Ultimately may add enough PV to do the job but in the meantime I wonder.

Thanks in advance,

Jay
Currently Tesla does not support a mode where you can tow one of their vehicles on it's own 4 wheels. There's a "Tow Mode" that can be activated temporarily to disable the parking brake and put the vehicle in the equivalent of neutral in order to winch it onto a flatbed. The "Tow Mode" is only active for a few minutes and only allows the Tesla to roll at a very slow speed. If the time runs out or the car rolls faster than the limit, the parking brake will be re-applied.

We don't know yet if Cybertruck will be different. Hopefully Tesla can see that people want the option and figure out a way to make it happen without increasing wear and tear to the drive units or battery pack.
 

VI Tesla

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I have a CT on order and may be about to buy a Super C Class RV (mid size diesel chassis) that can tow 15,000 lbs. I want to boon dock so may be away from chargers and love CT as large onboard battery can provide power off grid to the RV.

Question: While towing can I 'activate' the CT so that towing behind the RV recharges CT batteries through very mild re-gen?

Ultimately may add enough PV to do the job but in the meantime I wonder.

Thanks in advance,

Jay
As previously stated not an option and doubt it will be as not sustainable way to charge EVs.
In this scenario you might as well buy a gas generator to charge the CT and run the RV.
 

OneLapper

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Well, there is viable way to charge the CT while going down the road with his new Super C RV

The RV has house batteries and an inverter. The inverter make 110vac for the plugs, TVs, coffee maker. While on the road, the house batteries are charged by the RV's engine (alternator). Basically free energy due to the extremely low current demands of charging the CT on a 15 or 20amp circuit.

The CT will have 110vac charger that comes standard. Run an extension cord the CT's charger and plug it in! The CT will now be charging via the inverter, via the house batteries, via the engine's alternator. All this is happening while you're on cruise control and staring at that driver's side rear view mirror.

Yeah yeah, obviously the charger plug will be sticking out the left rear corner of the CT, asking to be ripped right off by something. A flying deer comes to my mind.

But, it CAN be done if needed......
 

Crissa

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Yeah yeah, obviously the charger plug will be sticking out the left rear corner of the CT, asking to be ripped right off by something. A flying deer comes to my mind.
Assuming you were going to do this, you'd create a special plug and tie into the wiring elsewhere.

Dragging an EV to tow it is just a dumb idea. At worst, you're wasting gas. At best, you're gaining a couple percent as you normally use linked brakes.

-Crissa
 

Luke42

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No.

You cannot "flat tow" a Tesla behind an RV.
Assuming that the Cybertruck is the same as the other Teslas this way, I'd approach this by making a solar trailer.

Take an enclosed race trailer. Put solar panels on top, and an off-grid inverter inside (possibly with a small battery to balance the system). Use that to charge the car.

Not a cheap solution, but a pretty good one.

--

Lastly, many RV-friendly campgrounds provide high-amperage grid power. It should be easy to charge a 500-mile Cybertruck at one of these places -- and that should last as long as a tank of gas in a conventional truck.

---

A backup method of charging an EV using a tow strap exists:
I'd only really be comfortable doing this with glider pilots in both vehicles, because we have a safety routine for towing two human-occupied vehicles with ropes at high speed that is pretty effective.

---

Personally, I've taken the travel trailer route.

I tow my travel trailer with a conventional truck (GMC Sierra) now, and I'll swap in the Cybertruck when I get mine. If the Cybertruck has a 2" receiver hitch, it'll take me about 20 minutes to swap my weight distribution hitch over.

(Hopefully the Cybertruck will have a 110V @ 30A outlet so that I can fully power my travel trailer from it when boondocking.)

---

I do want to be encouraging! Despite decades of prior art in RV world, there is still room for innovation and there is some hardcore engineering left to be done!
 

Blue Steel

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I believe Rivian will allow this option. No idea yet how much of a hassle it would be to use it. It might require someone to be inside the Rivian to use the regen in tow mode.

I don't think it's possible with any other EV.

Here's a tweet about it:

In the Long Way Up doc I also saw them dragging the R1T behind a tow truck and using regen to charge the battery. It's incredibly wasteful in terms of efficiency, but they were in the middle of nowhere in South America, where the electrical grid was bad. It was literally the only way for them to recharge.
 
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Luke42

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I believe Rivian will allow this option. No idea yet how much of a hassle it would be to use it. It might require someone to be inside the Rivian to use the regen in tow mode.

I don't think it's possible with any other EV.
Being able to be towed flat on four wheels is just a feature that you can just add to a vehicle during the engineering process.

The problem is that the engineering requirements are deeper they first appear. Allowing the drivetrain to freewheel for tens of thousands miles without excessive wear means that some of features required to allow 4-wheel flat towing are deep into the drivetrain's mechanical bits. It's not just software.

It's possible that Tesla or Rivian has included this feature in their vehicles, but I don't have any way to know for sure until I can download a copy of the owner's manual.

P.S. I'm consistently surprised by which vehicles you can (and can't) use as a "toad" (towed vehicle) behind an RV. You really have to read the owner's manual to see what the manufacturer is willing to allow under their warranty. There's very little rhyme or reason to it.
 

Blue Steel

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It strikes me as a feature that you can just add during the engineering process.

The problem is that it goes deeper than it would first appear. Allowing the drivetrain to freewheel for tens of thousands miles without excessive wear means that it goes deeper than just a software update.

It's possible that Tesla or Rivian has done this, but I don't have any way to know for sure until I can download a copy of the owner's manual.

P.S. I'm consistently surprised by which vehicles you can (and can't) use as a "toad" (towed vehicle). You really have to just read the owner's manual to see what the manufacturer is willing to allow.
There's enormous potential here. Imagine pulling an EV behind a RV and using the EV's regen as "trailer brakes." You would save the brakes on the RV while capturing that energy into your EV.
 

Luke42

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There's enormous potential here. Imagine pulling an EV behind a RV and using the EV's regen as "trailer brakes." You would save the brakes on the RV while capturing that energy into your EV.
Sure.

This is the standard 7-pin trailer wiring connector:
https://www.dieselhub.com/img/figures/7-pin-trailer-connector.jpg
There are literally millions of vehicles on the road which are prepared to integrate with trailers this way.

If the Cybertruck had a 7-in connector on the front to control its braking (and the software to match), then it could regenerate during braking.

(I suppose you could also use this connector to power large 12V accessories like a winch or a snowplow.)

It looks easier than integrating regenerative brakes into a trailer, because the battery is already in the CT.

This is a feature that Tesla wave to build in to the truck above and beyond allowing for flat-towing. I feel this kind of feature is unlikely on a 1st-gen vehicle, but I can't think of any major showstoppers.

We won't know flat-towing features are available until we get the Cybertruck owner's manual.

P.S. Discussions about this type of systems integration on this board often swerve into trailer/truck integration problems where integrating both HVDC and CANBUS seem like the only solution. This isn't strictly necessary in this case, because the CT is largely self-contained.
 
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Sirfun

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Hahaha, This thread reminds me of years ago when the work day would end and about 50 workers would be walking out to our cars. This one old welder dude would be behind everyone and yell out "hey asshole", just to see who would turn around!
So everyone who answers this guys question thinks they are a BRAINIAC. :D🤪
 

Newton

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p̶r̶i̶u̶s̶ c̶,̶ y̶o̶t̶a̶ p̶i̶c̶k̶u̶p, ⼕丫⻏🝗尺セ尺ㄩ⼕长
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didnt "engineering explained" tow a tesla with a raptor
 

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