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Solar-Powered Vandwelling
By Ubangi of the Yahoo Vandweller group

I was asked a while ago, "How did you design your solar system?".
I replied, "Well, of course, first I put the sun in the center, then I
figured Mercury should go closest, then I put in Venus, then
Earth...".

OK, nevermind.

My solar setup is very simple:

- Two 220Ah Lifeline AGM batteries
- One 85W Kyocera panel
- One 130W Kyocera panel
- One MorningStar ProStar charge controller
- One 2500W Cobra inverter
- One 6-post fuse box from West Marine
- 350Amp catastrophe fuse
- Connectors and terminators
- Lots of wire

The two batteries are connected in parallel: negative to negative,
and positive to positive. I used a huge phat 4/00 cable for that
connection (overkill, surprised?).

Then sitting on top of the negative terminal of one of the batts is a
350Amp catastrophe fuse. The other side of that fuse goes to...
everything else, which right now is the solar controller, the
inverter, and the chassis ground. Obviously the inverter and
controller also connect to the positive terminal as well (of the
same batt-- it's getting crowded on that terminal.

Stupid things I did wrong: I ordered batteries with
automotive-style posts. Then I had to buy universal posts to
attach to those. Duh! I should have gotten the batteries with the
metal tabs with the 3/8" hole in them, like marine batteries and
electric-cars.

The controller is very simple setup: the solar panels connect to the
solar input terminals via a #8 wire that is too long. The load (fuse
box) attaches to the load with a #10 wire which is too thin (I need
to replace it with something more like a #4). From there it's just
automotive fuses and #10 wire out to the loads (except the
computer, which is #8 wire).

The inverter was a PITA because it has two wires for positive, and
two for negative, both were #2 gague. I made them too short so
it's really crowded over there. I have to have the inverter right on
top of or right next to the batteries (which I'm told is probably a
good thing in the long run).

The whole thing is powered by two Kyocera panels in parallel
(negative to negative, positive to positive): one 85W and one 130W.
By accident I ended up sizing the system correctly, with the solar
capacity roughly equal to half the battery capacity.

I mentioned that I did not install the panels correctly-- we used
Kool Seal Patching Tape instead of a proper NEMA-rated outdoor
cable clamp on the junction boxes underneath the panels. So they'll
leak and rust over the years. I also don't have the cable between
the two solar panels properly secured yet.

It's not a perfect setup, but I can use my laptop computer, a 19"
LCD, an external hard drive, a USB keyboard controller, and two
Linksys routers, all night long. and the batts are charged up by
noontime in an overcast or fog. I also bought a 12v charger for the
Ryobi tools, and when I was doing a lot of sawing and drilling, I
could charge up the batteries for my projects within a few minutes
and my construction/conversion work was completely
solar-powered, which was nice. I am a musician and I've played
several outdoor shows, with this setup powering my amplifiers,
instruments, and a PA for vocals and other instruments. We even
played for several hours after sunset, and I had more than enough
battery power to keep it going. The system works, and it works
well.

The only thing I regret NOT buying, and should have, are NEMA
clamps for the cable, to attach it to the switch box on the solar
panels, and for the hole in the roof for the cable to come in. Oh,
and I also should have bought the correct connectors to connect
the #8 wire to the screw posts on the solar panels inside the
junction box.

The panels were pulling 11 amps at around 1PM in full sun when I
looked yesterday. That's about the maximum I get; and it's more
than enough to keep the batteries charged.

Friends helping install the panels.

One panel installed, waiting to be
connected to the second panel.

The panels are bolted down through
the roof of the box van

The batteries in their box, wired in parallel,
(positive to positive, negtive to negative). Since they
are AGM, they are safe to be inside the van.

The black wire comes down from the panels and goes into the
solar controller (the solar controller controls the charge from
the panels so it doesn't overcharge the batteries). Another
black wire goes from the controller to charge the batteries. A
red and black wire goes from the controller to the fuse block
(above it). As 12 volt appliances are added in the future, they
will be attached to the fuse box.

Here the inverter is connected to the batteries. It will power
all the 110 volt appliances. Notice the Ryobi battery and
charger. Home Depot sells these as cordless tools as kits that
include just a 18 volt drill or a drill and skill saw, along with a
huge array of other tools. There is also a 12 volt charger to
charge from the cigarette lighter plug. Highly recommended.

Here is a schematic of the whole system.
Don't skimp on the ground! An
inadequate ground will bring the whole
system to halt.