Suggestions on powering my new van build out?

[fatmacgyver]

Hello -

New to the forum but been lurking for years. I'm building out a new (to me) van and would love some suggestions from the community.

I'm working with a 2024 Ford Transit with the factory dual alternators.
My wife and I travel around - typically long weekends, going to dog competitions (active sports, hunting trials, agility, etc.). We often spend 2-4 back-to-back days of 4-12 hours hanging out around our vehicle with up to 6 dogs in crates inside the vehicle. I am building the van out using 80/20 or similar (likely just welding aluminum stock) to include dog crates and "cabinetry" for the AC, fridge, etc. and storage. We don't sleep in this van. At most, we'll spin the front seats around and hang out but we are typically outside of the vehicle.

The main reason for needing auxiliary power is Air Conditioning in the summer, heat in the winter for the dogs. We often have long drives (2-8 hours in a day) to and from our destination and will rarely if ever need to run the HVAC over night. So... lots of opportunity for alternator charging before and after running the HVAC. We are also usually places where running the engine to charge is no big deal.

This is also a "daily driver" so I am doing my best to avoid putting anything on the roof. So... no roof-mounted A/C or fans and no solar. I know, maybe blasphemy for some on this forum but my next project is a big solar upgrade at home

So... my plans...
I am going to insulate the van thoroughly and am planning on installing a:
Pioneer "under bench" 10,000 BTU AC AC (yeah... 110v AC Air Conditioner) - this is the main reason for the van essentially.

• In AC mode, it pulls 8.6A / 989W - constant, it is not a variable speed compressor.
• In heat mode, it pulls 6.9A / 794W - so, I'll "design" for the AC
• I will be ducting this directly into the dog crates
• I realize the Velit 12v option exists but with that I need a separate heat and ducting, don't have the space

12v Fridge (TBD on which specifically but a typical 4-5 cubic foot intended for van usage). I'll lean towards a more efficient version, haven't picked it out yet.

• From what I can tell these guys draw about 50ah / day on average.

Space inside will be a premium, so I am going to build 1 or 2 battery boxes under the van to mount my batteries in. If I can make them fit, I am currently planning on a pair of (or even 3) 12v 280ah Eco-Worthy LiFePO4 batteries (2p). I also may go the DIY battery route if space dictates. I plan on installing heating pads in and insulating my DIY battery boxes.

I already have a Xantrex XC 2000 inverter/charger that I intend to use to power the HVAC and provide 100A charging when on shore power. We'll have 120v shore power every night that we've run the HVAC extensively.

I am looking into direct alternator charging as my primary means of charging while on the road. I am digging into the design to do this properly now.

I should add that we have a Class B RV with a similar setup (Transit-based with a 110v roof mount AC with less battery capacity but with a generator). We take that for longer trips and sleep in it. The new van is for one-day trips (sleep at home) and I'm deleting the idea of a generator.

Sorry for all of the words above but that hopefully gives enough info to ask for advice! Here's what I'm looking to validate:

• Any thoughts on my plans for the batteries? Suggestions on how to be successful with that setup?
• Am I headed down the right path with direct alternator charging of the battery bank? We'll be draining the batteries (relatively) quickly and will want to be able to charge them quickly when they get low.
• Any issues with my inverter/charger selection?
• Anything else I should take into consideration?
• Am I missing something by not considering 24v or 48v for my setup?
• Any other thoughts/suggestions?

Thanks in advance for any feedback!!

 

[justinm001]

I would seriously consider getting a 12V AC unit. Running off an inverter you'll lose 15%+ efficiency. Plus if you're not routinely using the inverter for other things you're just eating idle consumption when AC isn't on. Setup the inverter and have a switch to turn on/off whenever you absolutely need it.

I wouldn't go 24/48v unless you find an AC unit. That would be better than 120V.

I wouldn't worry as much about heat. Plenty of options if you're using electric resistive heat. If in a cold climate consider a diesel heater.

Victron Orion XS 12/12 DC-DC converter is perfect for your alternator charging.

Undermount 12V Split System Air Conditioner for RV's

12V DC AC Air Conditioner undermount split system van sportsmobile conversion trailer rv recreational vehicle

undermountac.com

BTW I used to daytrip in my RV and solar makes all the difference. If you could add some way to hide the panels like under a roof rack or something, you should seriously consider it. AC runs mainly when its sunny out and since you're just sitting you're fine.

I'm curious on why you don't consider just running the van? Run a small battery to keep things running for an hour or so but outside that run the van. It'll power everything and shouldn't use too much fuel.

 

[HRTKD]

I don't know how you would install a mini-split air conditioner on a van, but that's the most efficient way to cool an RV. A 48v unit paired with one or more 48 volt batteries would be a nice setup.

As long as the van is actively being used, you shouldn't need a warming system. This is how my camper worked. In use = warm batteries. Not in use = cold batteries. For the not in use scenario I did use warming pads. If you get off the shelf batteries, be sure they have warming built in. Trying to warm off the shelf batteries that don't have a warming system is challenging because the warming pads cannot be attached directly to the cells.

You're going to have to oversize the battery bank since you don't want to add solar.

 

[RV8R]

Hi @fatmacgyver

So a Transit & I assume “CCP1 & “CCP2” ,,, so 500 amps @ 14v alternator charging ??

You should sort out how much energy you need & then how are you going to charge your batteries. You need to know what your durations for the discharge & charge.

Also, I didn’t catch the colour of your van, but white would be best to keep cool. The fewer windows the better & a decent insulation job is also something that you would benefit from. Also covering the exterior of the factory windows when parked to decrease the solar gain thru the glass.

Have you joined this Transit Forum ?

https://www.fordtransitusaforum.com/

Lots of good info there & Transit DIYers.



In Short; The heat gain “R Value” of your van needs to be calculated in order to size the Air Conditioning Equipment ,,, Then you have to design an electrical system to run it for your durations including charging.

This recharging or running the air conditioning could be achieved by generator, which you have stated you don’t want.

Electrical gear “Inverter & Fridge” etc, will increase the interior heat gain.

 

[0truck0]

A good DC compressor fridge should not pull 50 amps per day. Mine is a pretty big chest fridge/freezer and pulls 3.x amps running, but runs less than 30% of the time, so thats 1 amp per hour, I wake up and the fridge has puled down maybe 10 amps, 15 max since the sun went down.
Do add solar even if you think your driving will be enough, it probably will not and solar will not really add much to top of roof even to a dd.
To charge back what an air cond uses overnight is a big challenge for an alternator only. Im not sure you have the right numbers yet. If aircond uses 500 amp hrs and you want to charge that with alternator? You said a 500 amp alternator??? Wow #1, and that is a huge amt of power and a big load on the engine, and will such an alternator run at 100% duty cycle? because it will be running full bore for a long time. Even with your roof full of solar it will be insufficient to recharge 500 amp hrs; you might need a combo of things, solar, alternator and generator.
For heat, forget the ac unit heat pump, get a diesel heater, a 2000 btu will be over-kill for a van, but 2000 is the smallest they sell. It will roast you out and your windows will be open within the hour even on coldest of nights.
Undermount airconds will be great, other option: That frees you up to get a better air con. Look at "parking air conditioners". They come in 12v, 24v and 48v versions. Efficent, small and light and mounts on your back door and is a mini-split with a compact inside unit. The inside fan will run all the time, but the outside compressor/fan will cycle as needed. They are easy for any auto mechanic to work on and repair with common parts too.
If your batteries are inside then likely you will not need to heat them as the inside of van sounds like will be temp controlled all the time while traveling. And when not, then just be sure you are not charging them when batteries are below freezing (so disconnect solar, disconect alternator at those temps).

 

[fatmacgyver]

Sorry for replying to all of this at once, was on the road the past couple of days. I very much appreciate all of your time/thoughts!

I would seriously consider getting a 12V AC unit

My main concern with this build is keeping it a "daily driver". As much as we use it on weekend and I'm building the power system and HVAC for that part of it, we need to be able to use it daily and take it where we would our SUV that it is essentially replacing, i.e. normal parking lots, vet visits, drivethrus, etc. - this is what is prompting me to focus on adding minimal roof height (i.e. MOST 12V AC units) AND not taking up space inside the van. I'm currently leaning towards the "under bench" 120v AC to keep the under van space open for batteries (as opposed to using that space for the fans of an undermountac.com style 12v AC unit.) Haven't written that off but am considering it.

I wouldn't go 24/48v unless you find an AC unit.

Thank you for confirming!

If in a cold climate consider a diesel heater.

Again, back to the space. I know they don't take up a ton but this is a "plan b". As mentioned above my concern is that this is also an "off" or "way too hot for the van with 10 bodies in it" situation... like, I only need a bit of heating and their minimum BTU output is high. My van is "prepped" for a coolant line from the radiator, so I could add a traditional cab heater very easily if I go with the 12v AC, again, just taking up more space.

solar makes all the difference.

Ugh... I know. I am (based on this thread and my planning/research) considering an 8020-style low profile roof rack packed with solar panels but no roof mount AC. So, I would add maybe 3-4" height but that MIGHT still work for us.

I'm curious on why you don't consider just running the van?

There are situations where we can't (parked inside a structure, parked in quiet areas for a trial or similar.) We will likely idle the van a lot but I need to plan for the (at least occasional) full day where I can't. In this situation, I would likely take it for a drive to recharge batteries if it came to that but really hoping we can be in a situation where we can run the AC for a day.

A good DC compressor fridge should not pull 50 amps per day. Mine is a pretty big chest fridge/freezer and pulls 3.x amps running, but runs less than 30% of the time, so thats 1 amp per hour

Thank you for the sanity check there - it seemed like a lot but it's really the only serious (well, looks like not very serious) load that I'm contending with.

I hear you on the charging, too. I really need to dig into the specs on the factory dual alternator setup. Those days that we really drain the batteries, I will definitely have a 120v hookup at night, which will allow my 100A inverter/charger to help overnight. If I'm looking at a 1000Wh drain, I'm at about 2.5 hours usage per battery. If i'm charging at 100A+ it should be about equivalent time to charge. I'll get >100A from the alternator, maybe substantially more while driving. Then 100A while plugged in over night. So, if I can run the AC 8 hours then recharge the batteries in 8 hours, repeat... I should meet my goals.

mini-split air conditioner

I have opted to NOT install windows in the rear doors so that I can keep this as a backup plan (install a minisplit with the compressor mounted to one of the back doors). Would be cumbersome for using the back doors but if we need to, I may head this route if the 110v system fails or I bail on the idea.

So a Transit & I assume “CCP1 & “CCP2” ,,, so 500 amps @ 14v alternator charging ??

Correct. I have both CCP1 & 2. Dual factory batteries/alternators. I haven't read 500amps output (going to find those docs now!)

CCP1 & 2 are 120A + 60A rated (and fused) so 180A total. Trying to track down those actual specs/ratings before I buy anything for my charging system.

Also, I didn’t catch the colour of your van, but white would be best to keep cool. The fewer windows the better & a decent insulation job

A medium gray (un)fortunately - looks better, will definitely not help to keep cool - however NO windows in the rear. I am likely adding a window to the sliding door because that blind spot is dangerous while driving, but it will have a built-in shade and I'll have thinsulate-style window coverings for all of the windows (we have these for our Transit-based RV and they make a huge difference).

Have you joined this Transit Forum ?

Absolutely. Awesome group of people there - much like here - appreciate you making sure!!

Thank you all for your feedback - it's definitely influenced my thinking/planning. I'm crawling under the van with a tape measure this afternoon to see what I can fit under there (in terms of battery, AC options).

So far, I have purchased (4) 280ah eco-worthy 12v batteries. Unless something drastically changes, I'll be using as many of those as I can squeeze into my build (I have another vehicle that could use what won't fit). I also have the Pioneer 120v AC on hand. I'll start running that on the bench to see how much loss I get with my Xantrex inverter to decide if it might be worth it with my (now possibly larger than planned battery bank).

So... if anyone's read this far again (thanks again for all of your feedback above!!!)

... does anyone have any opinions on the Wakespeed W5000 "alternator regulator"?
https://www.wakespeed.com/product/ws500-pro-bluetooth-alternator-regulator/

I need to figure out if the "smarts" in the Ford "smart alternator" play well with this but it seems like the solution to getting the most charging power out of my alternators with the least likelihood of damage or dangerous situations. Not to mention reducing cost and complexity. As opposed to trying to size multiple DC-DC chargers vs. what the transit can safely provide both at idle and while driving.

 

[justinm001]

Can't you easily install an undermount AC without taking much space under the van? Surely there's room somewhere to mount the outside part, like under the engine or something. I'm assuming its like a mini split and you just run AC lines to it. There's various options and all seem to have 12V. Likely you can just run the condenser outside and rest inside.

CIGS panels are flat/flexible and if in the middle of the van no one would see them. No mounting or anything. If anything you can install a roof rack type thingy to help hide it from lookers.

If you setup an autostart on the van and had high power alternators with a bit of battery you could get by. Remote start it for 30 minutes every few hours. Also if inside a garage or something, less sunlight so less heat.

I'd also consider a rooftop/window fan vs an AC. How often are you really going to be in 80+ temps?

Another option to think about is some bumper hitch type setup. build a portable AC unit or whatever+ batteries and such on a removable bumper hitch. Hook it up when you use the van for events then unhook it when you're back to normal life. You could do something similar with roof rack and CIGS solar or other that are super lightweight. Build a 50lb aluminum thing and slide it up on the roof then hook into place in minutes.

Wakespeed and Zeus regulators are great if you have a dedicated alternator. Not applicable in your situation unless you can easily convert the 2nd alternator to an external regulator and run it just to the house side. Or get a new alternator and swap it out. I feel this is done often in Transit class B's.

If you're going with 120v AC then I'd think just getting some home portable type system would be easiest and cheapest.. just find an inverter type. You just need a hole for the exhaust/intake (get one with both exhaust and intake) Could even make some window cover that you just roll the window down and pop on when using.

 

[HarryN]

The ford transit dual alternator system is tied into the engine control computer, so adding another controller like the wakespeed is not useful. The dual alternators work as a team to keep up with the total system capability.

With the dual alternator setup on the transit, you can reasonably pull ~ 100 - 120 amps from CCP2.

( 100 amps ) x ( 12 volts ) ~ 1.2 kW with the engine running.

____________

The air conditioning load really dominates the situation, and basically pulls ~ 1 kW continuous while in use, and that is pretty typical.

So for example, 8 hours of AC use, it is roughly:

( 1 kW ) x ( 8 hours ) ~ 8 kW-hrs of battery capacity needed to do it.

____________

There is a high idle mode that can be triggered, depending on what your exact van has as options by working with some of the relays and connectors under the seat.

___________

Sterling makes some BTB chargers that are in that power range.

The other tried and true option is to attach an inverter to CCP2 ---- 12 volt input inverter ----- charger or inverter / charger

Both approaches work, both have their operational quirks that you need to play with to make it all work.

Cost wise, it is kind of wash, so really just a philosophical decision.

 

[fatmacgyver]

Can't you easily install an undermount AC without taking much space under the van? Surely there's room somewhere to mount the outside part, like under the engine or something. I'm assuming its like a mini split and you just run AC lines to it. There's various options and all seem to have 12V. Likely you can just run the condenser outside and rest inside.

Eh... they take up quite a bit of room if I am trying to mount my batteries under the chassis. The compressor (which is small) but also a fan (the largest part, which looks like a dual ~10" radiator fan in a serious housing) and the electric and coolant lines. It's not insubstantial.

CIGS panels are flat/flexible and if in the middle of the van no one would see them. No mounting or anything. If anything you can install a roof rack type thingy to help hide it from lookers.

Checking these out, thank you!

If you setup an autostart on the van and had high power alternators with a bit of battery you could get by. Remote start it for 30 minutes every few hours. Also if inside a garage or something, less sunlight so less heat.

I'd also consider a rooftop/window fan vs an AC. How often are you really going to be in 80+ temps?

Not doing a rooftop fan, it'll add too much height, will likely be installing something similar in the back window. I've gone crazy with fans in the past (6+ 18v Ryobi/Milwaukee fans + maxair roof fan, etc) - they don't cool dogs the same way that they cool humans. They don't sweat so fans have zero effect on cooling them unless they drop the actual ambient temperature in their cage/area. We are outside every weekend (and many week days) in the summer, in the midwest, we absolutely need AC.

Another option to think about is some bumper hitch type setup. build a portable AC unit or whatever+ batteries and such on a removable bumper hitch. Hook it up when you use the van for events then unhook it when you're back to normal life. You could do something similar with roof rack and CIGS solar or other that are super lightweight. Build a 50lb aluminum thing and slide it up on the roof then hook into place in minutes.

I much more highly value the easy usage of the rear doors for loading/unloading dogs and training supplies so I'm weary of making the rear area cumbersome... much more likely to look at a rear door mounted or roof mounted solution if I absolutely have to but this is definitely a good idea otherwise!

Wakespeed and Zeus regulators are great if you have a dedicated alternator. Not applicable in your situation unless you can easily convert the 2nd alternator to an external regulator and run it just to the house side. Or get a new alternator and swap it out. I feel this is done often in Transit class B's.

Yeah... I just wasted a couple of hours going down that rabbit hole... those are definitely out due to the "smart" alternator system on the Ford and, specifically for the Wakespeed their lack of support for cheap Chinese LifePO4 batteries (don't blame them, but they don't build profiles for the plethora of them!)

If you're going with 120v AC then I'd think just getting some home portable type system would be easiest and cheapest.. just find an inverter type. You just need a hole for the exhaust/intake (get one with both exhaust and intake) Could even make some window cover that you just roll the window down and pop on when using.

That thought crossed my mind too but I think this Pioneer deal that I bought is going to be the "easy" button usage wise (it'll be mounted inside a cabinet, air intake/exhaust directly through a hole in the floor) just need to make sure to get it enough power!

 

[fatmacgyver]

The ford transit dual alternator system is tied into the engine control computer, so adding another controller like the wakespeed is not useful. The dual alternators work as a team to keep up with the total system capability.

With the dual alternator setup on the transit, you can reasonably pull ~ 100 - 120 amps from CCP2.

( 100 amps ) x ( 12 volts ) ~ 1.2 kW with the engine running.

Yeah... Looking now at DCDC chargers vs. the Wakespeed or similar.

____________

The air conditioning load really dominates the situation, and basically pulls ~ 1 kW continuous while in use, and that is pretty typical.

So for example, 8 hours of AC use, it is roughly:

( 1 kW ) x ( 8 hours ) ~ 8 kW-hrs of battery capacity needed to do it.

____________

There is a high idle mode that can be triggered, depending on what your exact van has as options by working with some of the relays and connectors under the seat.

Thank you for mentioning this! I just found the Ford build guide (BEMM manual) that mentions this, I'm reading about it now. Looks like it's a simple single pin connection under the seat the way my van is specced out.

___________

Sterling makes some BTB chargers that are in that power range.

The other tried and true option is to attach an inverter to CCP2 ---- 12 volt input inverter ----- charger or inverter / charger

Both approaches work, both have their operational quirks that you need to play with to make it all work.

Cost wise, it is kind of wash, so really just a philosophical decision.

Yeah, headed down this path - thanks!

 

[justinm001]

Here's an install video in a transit. Seems like such a small amount of underbody space

My biggest concern for you if going 120v AC is the idle consumption and efficiency losses. You'll need 20% more battery plus all the heat from inverters are going to need cooled.

At 1000W you'll be burning 200w which is effectively a 200w heater in your van.

 

[ruzami]

I second Cruise N Comfort for low space high efficiency AC. I've got a 48v system coming for my van, and I've arguably got less interior space to work with than you. But they aren't cheap and I question my sanity every day for ordering this unit. I have a dream of a 32KW of battery only AC keeping me cool in the Nevada desert for a week. If that dream plays out, it'll be worth every penny. If not, it'll be just something to brag about with the kids down the street.