Solar panels not working normally in experimental?

I put some solar panels on an RV before switching over to the experimental. They’re down the centre aisle. Upon loading my saved game in the experimental I found that all the (partially charged) batteries I’d installed in the RV have no charge and they aren’t recharging by solar power.

What’s going on? Do you need to place the panels on the outside walls of the vehicle or something? I assumed they were roof mounted.

Update: I moved the panels to tiles marked as “out” on the vehicle. It’s now a summer day and I’ve been sleeping near the vehicle. It’s still on zero charge.

Help?

Is there anything on inside the vehicle?

Solar panels take a lot longer to charge, If you didn’t know.

Well I knew they’d been nerfed, yes. I have… three solar panels that should all be charging. All now on external tiles.

Nothing in the vehicle is turned on as far as I can tell. The engine won’t start so there’s literally zero charge it seems.

I do have some broken vehicle parts left in there including batteries. Could they be screwing it up somehow?

Battery charge now leaks out of damaged batteries.

Well, crap. That would explain everything then. OK I’ll get on with removing those.

By the way, do solar panels now NEED to be on external tiles or not? I’m really not sure after reading what I could find online.

No, solar panels should be fine on any tile.

Also note that (IIRC) batteries are a lot larger now, so when combined with the slower charge it can take quite some time for it to move from 0% to 1%, despite it actually charging the batteries.