Solar for a E-250 Van Conversion

[Divtruk]

I have recently retired and I am in the process of converting a 2010 Ford E-250 handicap van into my vacation camper. I do not plan on living in this van but I would like to be comfortable on some extended adventures. I am in the planning stages of the solar power system need some advice from you fine folks.

I have close to 40 years of experience working with low voltage DC systems so I do not need help with the wiring, termination, things of that nature. What I need is some advice on the components and a bit of the layout. The only thing I have purchased so far is 3 Renogy 100 Watt solar panels. I needed to get the panels first as I was welding up a custom roof rack and needed to know where to add supports. Also because a buddy had bought some he didn’t end up using and sold them to me cheap.

I do not want to go overboard on this system but I want enough power that I am comfortable in my travels. I come from the old school of thought to KISS (Keep it simple stupid). I want it simple and robust (if thats even possible). My initial component list is as follows

(3) 100 Watt Solar Panels - already purchased

Victron MPPT 100/50 Solar Charger

Victron Smart Shunt with BMV-712 Smart Monitor

200 Ah (minimum) of Lithium Batteries

2000 Watt Inverter

Victron Blue Smart IP22 AC/DC Charger

Manual 120 VAC Shore Power Transfer Switch


My plan is to have the AC/DC charger on the shore power side of the transfer switch. That way I start charging the batteries as soon as I plug in the shore power and don’t have to worry about turning the transfer switch inside the van.

So the initial questions I have are:

1. Should I go with the inverter and manual transfer switch and separate charger? Or step up to an inverter/charger? My worry is the inverter/charger combo is one more thing that can go wrong. A manual transfer switch is just that, a switch. Not much to go wrong

2. Is there any advantage or disadvantage to going with one 200 Ah battery vs. two 100 Ah batteries? My only thought was that going with two batteries lets me spread out my weight distribution in the back of the van.

I have attached a simple drawing of my system. I am sure these items have been discussed many times before so I apologize if I am rehashing things.

 

[justinm001]

A decent inverter/charger will last and the combo is one less thing to go wrong. Victron inverters are amazing and worth every penny

2 batteries gives you redundancy incase one goes bad

 

[jimf909]

I wouldn't worry too much about the inverter/charger going bad. My question is what are you running that requires an inverter? KISS may suggest that you run the van on 12 volts, unless you have some notable AC requirements. If your AC needs are few then don't go the inverter/charger route, rely heavily on the charger to keep the batteries charged and use the inverter for infrequent AC loads.

Will you always have shore power available to charge the batteries? Have you considered a DC-DC charger to charge the batteries from the van's alternator while you're driving? A DC-DC charger will take current from the alternator and charge LiFePo batteries correctly while limiting the load on the alt.

1) If you're committed to Victron the AC charger plus, say a Phoenix inverter will consume less space than say a Multiplus II 3000 watt inverter/charger which may be overkill.

2) The disadvantages of two batteries is slightly more overall space, more cabling required and increased cost (relatively minor) while the advantage is redundancy (perhaps slightly more than minor). Weight distribution can easily be addressed by tossing a duffel to the other side of the van. It's an E-250, it probably won't be offended batteries on one side of the van, remember, LiFePo batteries weigh less than FLA batteries.

 

[Divtruk]

I haven't had any preferences on brand of inverter yet. One of the reasons I'm on here is for some input. I was thinking a 2000 watt inverter would probably work for me. Most of my AC loads will be short time use, a small microwave and a coffee maker. Occasional longer runs with a small TV. I really don't know how much I will have shore power. As I just recently retired, I have not made any trips yet. The main thing is I want to be comfortable and have a few of the conveniences of home. (microwave and coffee maker)

I am trying to make as much as possible run on 12 VDC. I even found some TV's that run on 12V. The heater and stove are going to be propane.

 

[jimf909]

12 volt TVs immediately came to mind when you mentioned TV. So you want to run a coffee maker a 5-15 minutes a day and a microwave for 5-15 minutes(?) per day? For that, yes, a 2000 watt inverter will be plenty, esp. if you're not running hem both at the same time (easy to manage). It sounds like a 12 volt system will be fine and going to an inverter/charger will add cost, increase space requirements and complicate things.

Remember to turn your inverter off or to eco-mode when you're not using it to eliminate its ongoing draw.

If shorepower is unknown at this time, I'd recommend the DC-DC charger to charge the batteries seamlessly when you're driving.

Keep the questions coming.

 

[Rocketman]

I full-time in a MotorHome and I installed all Victron gear.

Here are a few changes to consider - and why.

Mppt 100/30 - will handle 400w of solar- the 100/50 is 700w - since you only have 300w - save the money.

Victron Dc-Dc 30a non-isolated charger - to top off the batteries when driving.

Smartshunt or BMV712- you don’t need both. The Smartshunt is cheaper and I never looked at the display when I had the BMV712- but the Bluetooth range is great on the BMV712- and kinda poor (abt 10 to 15 feet) on the Smartshunt.

Really consider the Multiplus 12/2000. One big advantage is the inverter automatically synchronizes the sign wave when plugging in, so no power blips, and automatically inverts when unplugged- my computers cannot tell when I start the generator or stop it.
(So skip the ip22 charge and manual transfer switch.

Also get the Cerbo and touch. It is totally awesome to track the power flows - and simple enough my wife will check the battery status. (Also the Cerbo will control/make changes to the Multiplus inverter.


Also consider adding a Victron smart BP65 and run all the 12 loads (except the inverter) through it. That way if you leave a light on and are away- it can shut down the loads BEFORE the bms shuts down - say off at 12.5v and back on at 12.8v
Good Luck!

 

[HarryN]

Since you are familiar with low voltage DC, then my suggestion right away is to make it a 24 volt system instead of 12 volt.

Rather than focus on the solar panels that you have - take some sheets of thin plywood or cardboard the size of a couple of different solar panels up on the roof and see what fits. Many times, other size panels such as 26 x 58 inch panels can be better for a van.

I build van electrical systems for people and a reasonably comfortable setup is 4 x 100 amp-hrs or equivalent size battery pack, 400 - 600 watts of solar, 2 - 3000 watt inverter.

If you want to be really comfortable it takes air conditioning and that consumes about 1 kW to operate anywhere that is really hot.

Harry

 

[Divtruk]

I did not realize the BMV-712 came with a shunt. I was under the impression you needed the smart shunt. Glad you pointed that out.

I have been doing my best to keep the original van electrical system separate from the house electrical. When I converted it from a handicap van it took quite a while to sort out and remove all the modification to the electrical the handicap company did. Took forever to find a few parasitic drains. I will have to look at how strong my alternator is before I would consider charging off of that

Does the Cerbo and touch screen take care of the functions of the BMV-712? Trying to avoid duplicate functions

 

[Rocketman]

The Cerbo &touch is a mini computer (and touchscreen) that connects to most all the other Victron components and summarizes and can controls them. It doesn’t replace the Smartshunt or BMV712.

You can roll your own Cerbo with a Raspberry Pi. (If you are so inclined).

One other really great aspect of the Cerbo - is if you have internet it can (for free) report the data to VRM server and you can see what’s happening on any internet connection device.
So when your rig is sitting at home or away - you can check on the status without physically being near it.

Check out YouTube for a few videos on the Cerbo .

 

[RV10flyer]

I started out with 400W on my Chevy express- standard length and height. Then I went to 1000W and now I’m going to 1620W. That’s about Max! Four REC 405 panels. ??