Thoughts on building a fully electric class A RV

[Phil G.]

Originally Posted by Captain8

Just starting some research but with a 200k budget for parts do you think it would be possible to build an RV frame/chassis only thats fully electric and capable of 500 miles?

The plan is to build a 35-40ft rig that has all 6 wheel drive and the ability to add/remove battery banks using a custom cart. This would allow me to save weight when I don't plan on long trips and even possibly carry extra banks if I need a much longer trip.

Most CG's seem to have a 220v 50amp plug, a 120v 30amp plug and a 15amp plug so I could utilize all 3 of these for charging and camping while I wait for the batteries to charge. This along with rooftop solar and a onboard generator would also work to increase charging or maximize distance.

One of the biggest issues with current RVs is we really have a need for a liftgate and would like to store a vehicle in the rear of the rig, thus eliminate the need for a trailer. Running full electric will remove the need for a rear DP engine so this is easily obtainable. I'm also thinking it'll help with the ability to store an electric vehicle that supports 2 way charging so I could utilize its battery banks to increase my distance.

I'd think having a much better distributed weight would dramatically improve ride quality and performance. I'm unsure if the weight would be more or less than traditional DP class A RV's. The plan is to develop the chassis and build it all myself then build the frame, slides and interior. The entire coach would utilize quality components like mini splits and actual insulation to maximize efficiency from the ground up.

I believe that even though its an RV it'll still apply as a kit car license so I can get it registered in my state. Need to look into the legality of all that.

Any thoughts? anything I'm missing?

I haven't read this whole discussion, so maybe someone has already covered the remote recharging aspect of an electric RV.

Here's a photo I found some time ago and have posted in various forums, but I think something like has to be the final solution to EV RV travel for those interested in camping and "refueling" out in the middle of nowhere. Of course it would require not towing a small get-around vehicle, as this solution requires towing of something else:

[Captain8]

Originally Posted by Phil G.

I haven't read this whole discussion, so maybe someone has already covered the remote recharging aspect of an electric RV.

Here's a photo I found some time ago and have posted in various forums, but I think something like has to be the final solution to EV RV travel for those interested in camping and "refueling" out in the middle of nowhere. Of course it would require not towing a small get-around vehicle, as this solution requires towing of something else:

For remote recharging I don't think solar is really viable unless you're planning on being gone a long time. Generator would make much more sense. My new coach has a 20k genny and a weekend running solid would get a decent charge, also plan on having 4 L2 ev charger ports so I could pull into a charging station for a few hours, hook them all up and have a great charge.

My old coach has 3000w solar and I'm planning on trying to fit 4000-5000w on the new one with a motor to lift each side up to track the sun. Also adding 700+w on the trailer roof. This is all for boondocking but I feel ill have plenty of surplus power

[P2_Hybrid]

Seems like you're pretty set on a full EV conversion, but I'm curious as to your thoughts on a P2 hybrid conversion. I did a short writeup on an EV forum (https://www.diyelectriccar.com/threa...rid-ev.209402/), curious as to your thoughts, seems like the cross-section of EV/Hybrid conversions and RVs is pretty small.

[Captain8]

Originally Posted by P2_Hybrid

Seems like you're pretty set on a full EV conversion, but I'm curious as to your thoughts on a P2 hybrid conversion. I did a short writeup on an EV forum (https://www.diyelectriccar.com/threa...rid-ev.209402/), curious as to your thoughts, seems like the cross-section of EV/Hybrid conversions and RVs is pretty small.

Interesting as I didn't even consider a P2 type with Axial Flux motor generator. Also my old rig was a 5.9 ISB and I had a 2014 Volt new which I loved the engine design.

I'm curious on how much power those types of motors can create and how to disengage the engine/transmission easily. Also wondering how it'll compare to EV powering the front wheels or tag leaving the original drive alone and then being able to just swap on the fly between drive modes. Even thought about how I could add just regen braking to the RV to charge house batteries and get additional braking power. But haven't dug into that much.

Update on my story. I purchased a Prevost XL2 40ft dual slide, one of the last 40ft they made. Built a 10kw 12V house system with 5kw inverter then added a 10kw 48v house system with split phase 10kw inverters. Left enough room to upgrade both to 20kw or even 30kw. Next to the 48V I have my 20kw genset which all this is right infront of my drive axle, I could rip this out and easily fit 150-250kwh. Even move the fresh bay next to it and add a bunch more. I purchased the Prevost as I wanted the best platform available (prevost engineering is amazing) as well as wanted something to last. Prevost also announced their EV project and Volvo (their parent company) has Polestar and EV busses so figured this was the best path forward.

Currently my house electrical is basically finished, I'm finishing up my 6 rooftop AC replacement and communication system now and once done I'll be replacing my solar to get over 5kw on there with a design to double it with air actuators and slides if I choose to upgrade down the road. Once thats done i'll be able to finish my ceiling then can begin the rest of the remodeling. Adding a shower and finalizing the layout so I can replace flooring and then finalizing everything else. I figured by this time next year my coach will be pretty close to done and I can dig into EV options.

My goal is to have everything in this coach fully redundant so keeping the engine and adding a P2 would be ideal but can get by with just having 2 sources of power and fully EV. Another goal is to be independent of diesel but still have the option to use if I choose, as well as maximize any and all electric resources available.

With that in mind I plan on using 2 CG 50a pedestals as I likely could reserve 2 spaces and use them both when camping to provide a charge. I also plan on using 4 RV L2 charging stations simultaneously as I figured late nights I could take up 4 spots and get a good charge in when others aren't using it.

The question remains on how much EV power do I need for a fully electric comfortable drive and what is the consumption all this with a 45k lb coach. I think I can expect .5 miles per KW so at 60mph I'd be burning 120kWh which means my 20kwh genset would only increase range 15% max so not sure if its worth the 1000lbs and space used. Could replace it with a pair of 5kw or so portable generators.

In addition to that genset bay I also have 2 completely empty bays that are around 3x4x8ft each and can carry a TON of weight. This supports my plan of having a main battery pack of maybe 200-300kWh then 2 additional "removable" battery packs. Or maybe just use the bottom of the bays for batteries and having the top halves removable.

If a L2 charger is 15kw then 4 would be 60kwh so if 120kwh consumption I'd charge twice as long as I drive at a charging station and at a CG I'd get and 20kwh for 2 50a plugs so 5 hours for every hour of drive.

[DrivingDan]

Originally Posted by Captain8

For remote recharging I don't think solar is really viable unless you're planning on being gone a long time.

No solar won’t, but there’s more electricity in the world then there is gas pumps, so finding a charge isn’t difficult. And as you say you can charge off a generator in a pinch. I have a Honda 6000is which charges my EV if I’m really stuck (which has never happened)

[P2_Hybrid]

You've got enough space (and weight) for batteries, my choice would be to do an axle swap to an E-axle on the rear -- Dana TM4 makes a dually e-axle, and there's a Canadian startup (https://www.edisonmotors.ca/carl) that prototyped a logging truck with that axle swap + diesel genset. Then, replace your genset with as many batteries as will fit, and stick an integrated generator (any motor that will put out DC in a range your BMS can take) on the output of your primary engine. It'll save you on battery cost, and won't limit you to campgrounds where you have access to multiple L2 chargers.

With that, you're a range-extended plug-in hybrid. For my setup, I've got a 20k# bus and I don't want it heavier, so adding 2-3000# worth of batteries is out of the question.

Separately, most 50A plugs are only rated at 100% for a short period, and long-term will run 80% of rated current, so keep that in mind. My 2c

[Captain8]

Originally Posted by P2_Hybrid

You've got enough space (and weight) for batteries, my choice would be to do an axle swap to an E-axle on the rear -- Dana TM4 makes a dually e-axle, and there's a Canadian startup (https://www.edisonmotors.ca/carl) that prototyped a logging truck with that axle swap + diesel genset. Then, replace your genset with as many batteries as will fit, and stick an integrated generator (any motor that will put out DC in a range your BMS can take) on the output of your primary engine. It'll save you on battery cost, and won't limit you to campgrounds where you have access to multiple L2 chargers.

With that, you're a range-extended plug-in hybrid. For my setup, I've got a 20k# bus and I don't want it heavier, so adding 2-3000# worth of batteries is out of the question.

Separately, most 50A plugs are only rated at 100% for a short period, and long-term will run 80% of rated current, so keep that in mind. My 2c

Thanks, this is spot on. I had same issue as you with 20k# on the old one which is why the swap

[P2_Hybrid]

Originally Posted by DrivingDan

No solar won’t, but there’s more electricity in the world then there is gas pumps, so finding a charge isn’t difficult. And as you say you can charge off a generator in a pinch. I have a Honda 6000is which charges my EV if I’m really stuck (which has never happened)

The problem with truck/bus/RV electric vehicles is the size of the battery pack. with a 6kW generator, you're looking at 100+ hours of straight charging to get the battery fully charged. Now you might not have to go all the way to full, but at 0.5 miles / kWh, that's 3 miles an hour, which is almost laughable.

I applaud @Captain8 for his goal of a true electric motorhome, but I don't think it's the right solution for RVing (at least how I want to RV). Looking forward to seeing how it turns out, I hope it works out for him

[DrivingDan]

Originally Posted by P2_Hybrid

The problem with truck/bus/RV electric vehicles is the size of the battery pack. with a 6kW generator, you're looking at 100+ hours of straight charging to get the battery fully charged.

Correct, the purpose would only be to enough to get to the next fast charger.

Having said that, I’m going to toss my 6kW in the back and roadtrip to Alaska before too long in my Silverado EV/450mi range (when I get it). It’s been done, the TFL guys drove a Lightning up there with much less range, but also had a generator backup emergency charger.

[adrian mcnei]

Alternator light on and beeping the battery still charging on Monaco Knight 2007

[radar]

Originally Posted by Captain8

Interesting as I didn't even consider a P2 type with Axial Flux motor generator. Also my old rig was a 5.9 ISB and I had a 2014 Volt new which I loved the engine design.

I'm curious on how much power those types of motors can create and how to disengage the engine/transmission easily. Also wondering how it'll compare to EV powering the front wheels or tag leaving the original drive alone and then being able to just swap on the fly between drive modes. Even thought about how I could add just regen braking to the RV to charge house batteries and get additional braking power. But haven't dug into that much.

Update on my story. I purchased a Prevost XL2 40ft dual slide, one of the last 40ft they made. Built a 10kw 12V house system with 5kw inverter then added a 10kw 48v house system with split phase 10kw inverters. Left enough room to upgrade both to 20kw or even 30kw. Next to the 48V I have my 20kw genset which all this is right infront of my drive axle, I could rip this out and easily fit 150-250kwh. Even move the fresh bay next to it and add a bunch more. I purchased the Prevost as I wanted the best platform available (prevost engineering is amazing) as well as wanted something to last. Prevost also announced their EV project and Volvo (their parent company) has Polestar and EV busses so figured this was the best path forward.

Currently my house electrical is basically finished, I'm finishing up my 6 rooftop AC replacement and communication system now and once done I'll be replacing my solar to get over 5kw on there with a design to double it with air actuators and slides if I choose to upgrade down the road. Once thats done i'll be able to finish my ceiling then can begin the rest of the remodeling. Adding a shower and finalizing the layout so I can replace flooring and then finalizing everything else. I figured by this time next year my coach will be pretty close to done and I can dig into EV options.

My goal is to have everything in this coach fully redundant so keeping the engine and adding a P2 would be ideal but can get by with just having 2 sources of power and fully EV. Another goal is to be independent of diesel but still have the option to use if I choose, as well as maximize any and all electric resources available.

With that in mind I plan on using 2 CG 50a pedestals as I likely could reserve 2 spaces and use them both when camping to provide a charge. I also plan on using 4 RV L2 charging stations simultaneously as I figured late nights I could take up 4 spots and get a good charge in when others aren't using it.

The question remains on how much EV power do I need for a fully electric comfortable drive and what is the consumption all this with a 45k lb coach. I think I can expect .5 miles per KW so at 60mph I'd be burning 120kWh which means my 20kwh genset would only increase range 15% max so not sure if its worth the 1000lbs and space used. Could replace it with a pair of 5kw or so portable generators.

In addition to that genset bay I also have 2 completely empty bays that are around 3x4x8ft each and can carry a TON of weight. This supports my plan of having a main battery pack of maybe 200-300kWh then 2 additional "removable" battery packs. Or maybe just use the bottom of the bays for batteries and having the top halves removable.

If a L2 charger is 15kw then 4 would be 60kwh so if 120kwh consumption I'd charge twice as long as I drive at a charging station and at a CG I'd get and 20kwh for 2 50a plugs so 5 hours for every hour of drive.

Heads up. Although an L2 J 1772 station is capable of 19.2 kw, the vast majority are 8 KW. And I mean the VAST majority, and many are less when connected to 208 volts instead of 240 volts.

I am enjoying your posts and looking forward to hearing how your project goes.