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Discussion Starter · #1 ·
Short version:

  • Standing euro cargo van - I think Dodge Promaster might be the ideal shell.
  • Doing vanlife/RV conversion
  • Solar - lots of room to cover the roof, how good could this get? We talking maybe 10-20 miles of range charge per day, or could it be even better? What cost could I anticipate for that?
  • Standing height necessary, though it adds drag.
  • Tesla used/junkyard parts for batteries and motor, though would love to understand better what other options are our there and if anything else makes sense
  • I am thinking 100-160kwh in battery, maybe just laid in the floor of the cargo area of the van itself?
  • Maybe sticking a generator in the engine bay?
  • Want to mount a motorcycle to front of van.
  • Am worried about weight; ripping engine and transmission and driveshaft out but adding electric motor and lots of batteries is going to be a significant net increase in weight, no?

So, I've been planning to do the vanlife thing. I'm medium-level mechanically inclined. I decided to go the boxy euro-van style route. Thing is, mechnically I don't trust them, and they're expensive. Cheapest worn out ones are $15k, one with reasonably low miles would be at least $25k, and would require a bit of hunting. I decided best option would be a Transit--seemed the least unreliable--with a medium or high roof (high enough to stand in; I'm about 5'10", so the medium roof might just barely work, need to get in one to decide).

Then I heard that Ford is about to release an electric version of the Transit! Looked into it--taking orders July, 43k after tax credit makes it pricey, and range is low at 108 miles (with a 64kwh battery, though I also think I read it was determined they would be about 30% less efficient than comparable tesla battery-to-motor) for the high roof option. Hmm...

So then I started wondering about building my own? And now I'm here.

Body
I had been thinking Transit, since it was the best compromise of price/reliability, but the other options...
  • Sprinter: rejected, because it means still some Mercedes parts (maybe some kind of wheel bearings or something down the line, or windshield, etc., dunno), and narrower (width is nice in RV, though less nice for mpg/range I guess); if I should reconsider, let me know
  • I think the Dodge Promaster might actually make more sense for this build though, as the roof isn't quite as tall as the High Roof on the Transit (so, less drag) but still taller than the medium roof, so definitely tall enough to stand up in.
  • On the other hand, that extra cabin height on the high-roof Transit would be a really nice feature for having clearance above bed, and/or fitting more batteries in the floor potentially. On the other-other hand, though, I think the high roof may have tighter weight limits when it comes to solar panels on roof...
  • Based on how much weight I'm looking at here, seems like a 250/350 options is going to be required either way
  • Hoping I can find a good body with blown engine for $10k at most. Worst case I can find one with a worn out engine for ~$15k it seems and try to sell off innards to make the difference, but that would definitely hurt the budget.

Batteries
  • Tesla ones are expensive. From a site like EVwest, it'd be $33k for 100kwh of battery. I did see a complete 90kwh Tesla battery on ebay for $17k at a quick glance, though. I also saw a video of another large van (different kind, though, from a defunct company from the early 2000's) being converted to Tesla stuff by EVwest, and they put in two 80kwh Model 3 battery packs (so, a total of 160), which they said would give them a 200+ mile range.
  • I am thinking I'd like to install them in slide-out drawers for servicing, but that's just a vague idea at this point.
  • Are other batteries worth considering? I do have weight considerations.
  • How hard will it be to make sure I'm not going to be at risk walking around on top of these batteries of causing issues (that is, how much weight will it take to have enough materials to make it ok to walk on top of)? Should I consider installing them differently?

Motor
The E-Transit will be about 240hp. Seems like any single Tesla motor would get the job done. Transit is FWD, Ram is RWD. Had been thinking of just using the existing driveshaft in a Transit and putting tesla motor in engine bay, but now I'm thinking for weight savings it's worth it to try to engineer the Tesla on-axle option into the rear of whatever vehicle I go with. Any other motors I should be considering?

Transmission
Seems like a good idea to add a manual transmission to get range maximized +low gear for weight going up steep mountain environments. I saw 5% range improvement as a number when I looked into this, and that high/low gear is generally considered a 'good idea' from a pragmatic point of view. Is this a good idea? Or way more effort than its worth? Am I totally missing something? Is there some great minimalist low/high tranny option that would work that makes more sense than transplanting an entire 5 speed out of some truck and shoe-horning it in?

Generator in Engine Bay Idea:
An interesting idea I had... how about putting a generator in the engine bay and hooking it up to the built in gas tank? I know it won't charge the batteries faster than they deplete or anything, but could be run while driving to give extended range, and if run while parked would be quieted by being in engine bay, and allow essentially keeping a reserve-self-charging option--combined with the solar panels, it might give some kind of decent emergency option, no? Is this completely hare-brained?

Mounting a Motorcycle:
I'd like to mount a light motorcycle to the front of the vehicle onto a front-mounted tow-hitch. This will add weight (though if batteries are in the back, that weight will help balance it out and improve ride I think), and hurt aerodynamics. Idea is it means when parked I don't have to drive the house around everywhere if the weather is OK, and having a second vehicle is a godsend in many possible scenarios. I'm unsure how high the impact will be on range from this, though. Mounting on back would prevent opening doors and spare tire, and towing obviously adds far more complexity that I'm striving to avoid.
 

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Discussion Starter · #2 ·
Oh, budget:

Obviously, I'd like it as cheap as possible. That being said, I'd really love to be able to pull this off (just the batteries/motor/body basic functionality) for $30k. (Can spend more on Solar/Generator/Interior/Motorcycle mount stuff after that, according to price/weight/discussions on how much value I'm really adding.)

As for time:

I have a guy who has been wanting to learn/try converting a vehicle to electric for years. He's able to weld, and has a full garage of kit for this, and is very savvy in electrical and mechanical work, so that's a plus. I'd like to be able to be on the road in 4 months, maximum 6 months, so advice on reaching those targets are welcome.
 

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  • Solar - lots of room to cover the roof, how good could this get? We talking maybe 10-20 miles of range charge per day, or could it be even better?
Let's say the roof area is about 2 metres by 4 metres, so that's 8 square metres. Insolation (the amount of solar energy hitting the earth's surface) is very roughly 1 kW/m2 at noon in clear weather, so that's 8 kW. A solar cell is 20% efficient if you're lucky, so that much panel area could ideally produce 1.6 kW. Over a day in clear weather you might get the equivalent of four hours of full sun (actually 12 hours, but mostly not direct as the angle to the sun changes) so at the equator the van might collect 5 kilowatt-hours (kWh) of energy. That's enough to drive perhaps 10 km (6 miles)... and it's a highly optimistic and ideal estimate.

Also, in an RV situation you will need energy to live (ventilation, lighting, cooking...), and much of what you can get from a rooftop array will go to that. I think rooftop panels are a great idea - I just don't think that it's reasonable to expect to drive anywhere on energy collected that way.
 

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  • I am thinking 100-160kwh in battery, maybe just laid in the floor of the cargo area of the van itself?
  • How hard will it be to make sure I'm not going to be at risk walking around on top of these batteries of causing issues (that is, how much weight will it take to have enough materials to make it ok to walk on top of)? Should I consider installing them differently?
You can't walk on a battery, or even on a floor panel supported by a battery. This would mean building a complete structural floor above the cargo floor, making a space between them for the battery. That would take a lot of height, so even the tallest of these vans would then be short of headroom.

I suggest trying to find a way to put the battery under the floor, or at least in the base of cabinets (such as seating).
 

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Generator in Engine Bay Idea:
An interesting idea I had... how about putting a generator in the engine bay and hooking it up to the built in gas tank? I know it won't charge the batteries faster than they deplete or anything, but could be run while driving to give extended range, and if run while parked would be quieted by being in engine bay, and allow essentially keeping a reserve-self-charging option--combined with the solar panels, it might give some kind of decent emergency option, no? Is this completely hare-brained?
That would work, and if you must carry a generator in an EV under the hood is a good place for it; however, if you drive it as a series hybrid that's likely to be less efficient than just driving with the original engine.
 

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  • Am worried about weight; ripping engine and transmission and driveshaft out but adding electric motor and lots of batteries is going to be a significant net increase in weight, no?
Yes, with a large battery there will be a significant increase in weight. Fortunately, a properly equipped commercial van has a lot more payload than needed for a basic RV interior, so it can also carry substantial battery weight.
 

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Van Comparison

I decided to go the boxy euro-van style route. Thing is, mechnically I don't trust them, and they're expensive. Cheapest worn out ones are $15k, one with reasonably low miles would be at least $25k, and would require a bit of hunting. I decided best option would be a Transit--seemed the least unreliable...

Body
I had been thinking Transit, since it was the best compromise of price/reliability, but the other options...
  • Sprinter: rejected, because it means still some Mercedes parts (maybe some kind of wheel bearings or something down the line, or windshield, etc., dunno), and narrower (width is nice in RV, though less nice for mpg/range I guess); if I should reconsider, let me know
  • I think the Dodge Promaster might actually make more sense for this build though, as the roof isn't quite as tall as the High Roof on the Transit (so, less drag) but still taller than the medium roof, so definitely tall enough to stand up in.
  • ...
I don't think they're bad in general, but as with any vehicle there are weak points. The Transit uses a flex coupling (or "Guibo joint") at the transmission output, and that regularly dies. You can just replace it, and live with the unnecessary maintenance item because someone went cheap and didn't specify a proper CV joint.

Parts cost with anything wearing a "Mercedes" badge would be a concern in North America, but my real concern with a Sprinter would be rust. Just judging from what I see on the street, the first-generation Sprinter has the worst rust problems of any vehicle built by any manufacturer in this century - if I worked for Mercedes, I would be embarrassed.

Whatever the dimension differences, the huge difference between the ProMaster (which is a Fiat Ducato) and the others (in the versions sold in North America) is that the Promaster is front wheel drive and the others are rear wheel drive (with optional four wheel drive), so the mechanical layout and the underfloor structure are different.

Transit is FWD, Ram is RWD.
It's the other way around, although the complete situation is more complex.
  • The Ram ProMaster is FWD, with a transversely mounted engine and transaxle. The Fiat Ducato on which it is based is also available AWD, but the Ram version is not.
  • The Transit is made is both FWD (transverse engine) and RWD (longitudinal engine) versions, but the FWD is only used in the lighter models and only the RWD is sold in North America as far as I know. There is also an AWD, based on the RWD.
  • The Sprinter has been RWD, with optional AWD based on the RWD. A FWD version was recently added, only for the 2019 model year, only in some variants, and I don't think it's available in North America.
 

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Energy Consumption

Then I heard that Ford is about to release an electric version of the Transit! Looked into it--taking orders July, 43k after tax credit makes it pricey, and range is low at 108 miles (with a 64kwh battery, though I also think I read it was determined they would be about 30% less efficient than comparable tesla battery-to-motor) for the high roof option.
I don't know what you really mean by efficiency. If you mean that energy consumption would be 30% higher per distance travelled than a Tesla... well of course it will be much higher, because there is no comparable Tesla. Tesla doesn't make enormous vans. It doesn't matter what battery and what motor you use, this van will take much more energy to drive than a car due mostly to the aerodynamic drag (but also due to the weight).
 

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Mounting a Motorcycle:
I'd like to mount a light motorcycle to the front of the vehicle onto a front-mounted tow-hitch. This will add weight (though if batteries are in the back, that weight will help balance it out and improve ride I think), and hurt aerodynamics. Idea is it means when parked I don't have to drive the house around everywhere if the weather is OK, and having a second vehicle is a godsend in many possible scenarios. I'm unsure how high the impact will be on range from this, though. Mounting on back would prevent opening doors and spare tire, and towing obviously adds far more complexity that I'm striving to avoid.
I understand the logic, and I agree that having a very small vehicle makes some sense - it's like a yacht with a tender or dinghy. But...

None of these vehicles are intended to support a load up front. I doubt you'll find a front-mounted hitch receiver for any of them.

Even if you find or build something, a motorcycle will block the headlights, marker lights, and turn signals.

Maybe embrace the idea of pedalling?
 

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For an idea of how to package components in an EV conversion of a van, this article shows how Ford arranged the E-Transit:
The New 2022 Ford e-Transit Will Carry the Spare Under the Front, More Details are Revealed

They chose RWD, despite having a FWD version available and needing a new independent rear suspension to allow RWD with the battery in the middle, probably because with all of that battery weight the vehicle will be rear-heavy in use. The space under the hood is mostly used up with all of the electronics needed, plus the spare tire.
 

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Motor
The E-Transit will be about 240hp. Seems like any single Tesla motor would get the job done.
...
I'm thinking for weight savings it's worth it to try to engineer the Tesla on-axle option into the rear of whatever vehicle I go with. Any other motors I should be considering?
A single Tesla Model S or Model X motor might overheat in use. They are capable of putting out lots of power, but not much continuously because the rotor gets too hot. A Model 3 motor - although rated at lower peak power - might be a better choice.

The motor from any of the heavier production EVs is worth considering, if you have a way to control it.

Since all production EVs mount the motor at or adjacent to the driven axle, used with an independent suspension, all production EV drive units (motor plus transaxle) can potentially work at the front (if the van's suspension allows for driven axles) or at the rear (if you are willing to convert the van to an independent rear suspension).
 

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Extreme idea: tractor-based RV

It is common in Europe to build what we could call a Class C motorhome (using a commercial truck or van cab and chassis with an RV body) by using what Mercedes calls a "tractor head" and Fiat calls a "tractor cab": the front of a front-wheel-drive van, just to the back of the cab, with a rear frame and rear suspension built for this purpose (not using the van's rear structure or chassis at all) and the RV body on that. This allows the motorhome designer maximum flexibility in designing the rear structure to hit the desired floor height and to accommodate RV components such as tanks.

This was the method used by Winnebago to build the LeSharo (using a Renault Trafic tractor) and later the Rialta (using a VW EuroVan, a.k.a. Transporter T4). You could even EV convert one of those motorhomes, instead of both converting a newer van to an EV and converting it to an RV. Currently none are sold in North America as far as I know, but they're common in Europe using the Ducato tractor and AL-KO rear chassis.
Here are EuroVan tractor cabs hilariously bolted together in pairs so they can be handled for shipping, at the Winnebago factory a couple of decades ago (courtesy RialtaInfo):
122712


In an EV conversion RV, this approach might allow for everything wanted to fit under the floor - both the high-voltage battery and the tanks (fresh water and waste) - because you can pick the depth and configuration of the underfloor space. The drive motor could go in place of the engine, or in the rear. Because the original powertrain is not being used, this could even be done by cutting off a RWD van, but it would be easier for structural integrity to use a "tractor" which is already cut off and prepared for a rear frame to be bolted on... and the factory would only do that with a FWD van.

Of course this sort of thing will look like a motorhome, rather than a cargo van, unless you make a point of making it look like a cube van. I don't know if the "stealth camper" thing is a factor to you, as it is for some "van life" enthusiasts.
 

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Discussion Starter · #13 ·
Wow, what fantastic responses. Thanks so much! I'll try tor respond quote-for-quote as you have.
 

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Discussion Starter · #14 ·
Let's say the roof area is about 2 metres by 4 metres, so that's 8 square metres. Insolation (the amount of solar energy hitting the earth's surface) is very roughly 1 kW/m2 at noon in clear weather, so that's 8 kW. A solar cell is 20% efficient if you're lucky, so that much panel area could ideally produce 1.6 kW. Over a day in clear weather you might get the equivalent of four hours of full sun (actually 12 hours, but mostly not direct as the angle to the sun changes) so at the equator the van might collect 5 kilowatt-hours (kWh) of energy. That's enough to drive perhaps 10 km (6 miles)... and it's a highly optimistic and ideal estimate.

Also, in an RV situation you will need energy to live (ventilation, lighting, cooking...), and much of what you can get from a rooftop array will go to that. I think rooftop panels are a great idea - I just don't think that it's reasonable to expect to drive anywhere on energy collected that way.
Excellent, thanks. Yeah, there are serious limitations, but if I were to go out and park somewhere for a few days / two weeks or more, it could enable me to just passively charge the battery--or at the very least, be making sure that doing things like using my computer and lights and so on aren't sucking away my ability to get back to town! Meanwhile, it won't hurt range. Thanks for the estimate, though, that's helpful. I think it makes sense to add even if using a gas van, so I'll do it anyways, and we'll just see in the end how it ends up going. Really appreciate those estimates, that's exactly what I was hoping for.

One other question, though I'm 80% sure I can imagine the answer--there's no 'extended' "portable" solar array I could/should bring with me option that I could lay out when parked to improve my rate of recharge substantially, is there? Would we be looking at something like 100-200 lbs of panels, significant space being taken up, and not much extra energy generated? Anyways, I think the generator option in combination with some amount of solar on the roof sounds like the ideal all around from what I'm gathering.
 

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Discussion Starter · #15 ·
You can't walk on a battery, or even on a floor panel supported by a battery. This would mean building a complete structural floor above the cargo floor, making a space between them for the battery. That would take a lot of height, so even the tallest of these vans would then be short of headroom.

I suggest trying to find a way to put the battery under the floor, or at least in the base of cabinets (such as seating).
Great info, not something I had thought about until I was writing this post out, and I'm glad I did. Makes the build a bit more complex, but glad to know this now at this stage.
 

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Discussion Starter · #16 ·
That would work, and if you must carry a generator in an EV under the hood is a good place for it; however, if you drive it as a series hybrid that's likely to be less efficient than just driving with the original engine.
Indeed, driving with it running is a secondary purpose. I would plan to just use it as an electric vehicle, but having a generator there means far more flexibility when driving an EV into remote areas.
 

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Discussion Starter · #17 ·
Yes, with a large battery there will be a significant increase in weight. Fortunately, a properly equipped commercial van has a lot more payload than needed for a basic RV interior, so it can also carry substantial battery weight.
Would you happen to be able to give a general ballpark comparison on what I might expect? Removing 800 lbs, adding 1000 lbs, or is that way off?
 

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Discussion Starter · #18 ·
You can't walk on a battery, or even on a floor panel supported by a battery. This would mean building a complete structural floor above the cargo floor, making a space between them for the battery. That would take a lot of height, so even the tallest of these vans would then be short of headroom.

I suggest trying to find a way to put the battery under the floor, or at least in the base of cabinets (such as seating).
Excellent, thanks. That was going to make the build a lot simpler in my head, but I'm glad I asked. I'll have to just look at the body in question and get some measurements on the batteries I guess, see where/how I can manage this.

Either I find a way to put it all under the cargo area itself, or I put it under cabinets, the bed/storage area in the very back, under the hood, and/or the seats. Sounds like this will be a somewhat involved part of the build, though, sorting this all out. Looking at a model 3 battery, it seems like it can be split into 4 long slices, with some complexity. Any other thoughts or resources or things I should be aware of on this?
 

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Either I find a way to put it all under the cargo area itself, or I put it under cabinets, the bed/storage area in the very back, under the hood, and/or the seats. Sounds like this will be a somewhat involved part of the build, though, sorting this all out.
Yes, it's definitely a major challenge.

Looking at a model 3 battery, it seems like it can be split into 4 long slices, with some complexity. Any other thoughts or resources or things I should be aware of on this?
The Model 3 battery is well known for being difficult to use, because the modules are so long... but I had the same thought, that all four the modules could be stacked and fit under a bed or bed-length seat. tiger82 shows a Model 3 battery repackaged this way in the recent update to his Tesla-motor Cobra race car. In his 1950 Jaguar conversion, SuperfastMatt opens up Model 3 battery case and rearranges the modules to fit in his car.
 
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