2 system setup

[WanderingBeing]

So I've got this idea in my mind, and I am trying to do a bit of research to see if anyone has done anything like this, or if it is even possible (I'm pretty sure it is, it's just how complicated it will be... I'm looking for simple) I'm looking at outfitting a cargo van as a small, more back woods friendly solo camper with a solar setup, but also having a solar array system on a camper trailer. I'm looking to have each one work on it's own, but when I'm using the van and the trailer an easy way of combining both battery banks & solar setups into a giant one. I don't want to have to reconfigure the solar panels wiring every time I unhook the trailer. I'm also wondering about 12v vs 24v. I want to be able to use a fairly beefy desktop pc, which runs on 12v anyway, but from the reading I have been doing it's easier to get a 'clean' 12v for the computer by stepping down the 24v system than trying to boost the 12v system from slight drops. The only hangup with just outright doing the 24v system is most rv & camper appliances are 12v, and the 24v systems tend to be a bit more expensive. One thought I had to get around that was again stepping down the 24v to 12v for the fridge, ac, pumps & other 12v systems. I hope that all makes sense and sorry if it's a bit scatterbrained. If anyone has any thoughts, tips or suggestions I'd love to hear it!

[organic farmer]

So I've got this idea in my mind, and I am trying to do a bit of research to see if anyone has done anything like this, or if it is even possible (I'm pretty sure it is, it's just how complicated it will be... I'm looking for simple) I'm looking at outfitting a cargo van as a small, more back woods friendly solo camper with a solar setup, but also having a solar array system on a camper trailer. I'm looking to have each one work on it's own, but when I'm using the van and the trailer an easy way of combining both battery banks & solar setups into a giant one. I don't want to have to reconfigure the solar panels wiring every time I unhook the trailer.

We attend an annual homesteading / off-grid / sustainable fair in this region. One of the vendors has an old school bus and a food trailer, both are covered in solar panels. Sounds very much like what you are thinking of doing.

... I'm also wondering about 12v vs 24v. I want to be able to use a fairly beefy desktop pc, which runs on 12v anyway, but from the reading I have been doing it's easier to get a 'clean' 12v for the computer by stepping down the 24v system than trying to boost the 12v system from slight drops. The only hangup with just outright doing the 24v system is most rv & camper appliances are 12v, and the 24v systems tend to be a bit more expensive. One thought I had to get around that was again stepping down the 24v to 12v for the fridge, ac, pumps & other 12v systems. I hope that all makes sense and sorry if it's a bit scatterbrained. If anyone has any thoughts, tips or suggestions I'd love to hear it!

One of my neighbors went off-grid in the 1980s. His house is entirely 12vdc. I was strongly tempted to do the same. It is a VERY simple elegant system. It is also seriously lower cost.

I would do both setups using 12vdc. Then buy a couple small inverters, one for each appliance that needs 120vac.

The only serious problem or issue is that you can rarely ever, mate these two systems.

Consider: two battery banks. Both 12vdc, both 500ah. But the State-Of-Charge [SOC] will always be different between them. Anytime that you attempt to connect these two battery-banks together, the difference is SOC will cause a spark / fireball that will burn a hole through your chest, vaporize all the cables and melt the lead terminals.

To connect them together, you will need to float charge both battery-banks to 100% SOC. Then use a high resistance jumper to make the connection. Before shifting to a low resistance jumper.

[Logan005]

refrigeration at 12 volts is very inefficient, most of the 12 volt units I am aware of are 12/24 volts, 12/6 amps. Making a 24 volt system benefit obvious. Your computer will need a $20 step down converter.