By The Light Of Day

Solar stuff is confusing I will grant you that.  I spent about two months doing solar panel research and quite frankly, when I was all done, I felt like I knew less than when I started.  There is a ton of information out there but a huge selection of equipment on the market.  Having such a diverse selection, and rumors of incompatibilities, makes it difficult to find someone who is using the same configuration of equipment.

Before I get into all that though…  Something for you to check out, I have setup a Living on The Stealth Facebook page. Just click on this link https://www.facebook.com/livingonthestealth/  ‘Like’ and ‘Follow’ this new page you can get all the me with 100% less politics.  Or, you know, 99% less, anyway…

 The dealers won't actually give you much advice. They will only tell you to consult an electrician.  Or, they try to sell you a package with a bunch of stuff you don’t need.  What I needed was two solar panels and something to allow those panels to be hooked up to my batteries to charge them.  That was it.  I didn’t need a bunch of extra stuff, I didn’t need a bunch of mounting hardware.  I am going to tell you what I bought and discovered along the way.  I don't vouch for this information at all other than to say it seems to currently be working for me.

First off I checked with the solar guy I occasionally run into at the grocery store on weekends.  He and I have talked solar for years.  Even before solar we had talked about alternative home heating when I ran one of those blogs.  But, he has gotten to be kind of a solar big shot in the area now.  I sent him what I was looking for and some questions on what I was confused on.  He sent me a picture of the job he just finished, which was like sixty panels on a stock building, and a promise he would get back to me in a couple of days.  That was the last I have heard from him.

Starting out I contacted a company called Wholesale Solar. They advertised their low prices and helpfulness so I was hopeful.  A disadvantage might be I don't like to call anyone.  I always just figure email I can re-read, I can formulate questions. I can be effer-goddamn-vessent.  On the phone, not so much.

But emailing Wholesale Solar was about a week turn-around per mail.  The replies I got seemed to be cut and paste jobs. I realize I don't have a standard situation here with panels on the top of a cargo van. So I was making some allowances for a bit of confusion.  The other thing, I was asking for a bunch of information on a two panel order.  I am guessing if I was talking about two hundred panels I could have gotten a little better service.  The replies from Wholesale Solar seemed like the person hadn't read the exchange at all and finally I gave up.

Id like to send some information about the panels we offer. It sounds like you have a really cool project, but Im not sure the 260w or 295w panels will work for your project. How much space do you have? These panels are about 6’ x 3’. When we size panels for RVs or vans, we typically use the smaller 100w panels which are much smaller. Here is a link to an rv system on our website. Ig this is something you would like to pursue, let me know!
This is a two panel rv kit-
https://www.wholesalesolar.com/1890250/wholesale-solar/complete-systems/sundancer-rv-kit
And this is a four panel rv kit-
https://www.wholesalesolar.com/1890260/wholesale-solar/complete-systems/king-of-the-road-rv-kit
Thanks for reaching out.
Ricky Raffaini
412 N. Mt. Shasta Blvd.
Mt. Shasta, CA 96067
Toll Free: 800-472-1142
Local: 530-926-2900
Fax: 530-926-1162
http://www.wholesalesolar.com

I emailed back to them some additional information about the project and then the second reply referred me to a $7000 package with four panels for a house rooftop install.

Solar panels have special DC connectors.

Next was Renogy Solar.  This place was actually worse than Wholesale Solar.  I wrote to them, they answered nothing in their email, it was total marketing BS including a link to a package that cost almost $6000.  When I replied, again describing my project, I got the same exact email reply from them.

In the end I just took a shot in the dark.  I ordered both the panels and the charge controller from Amazon.  Which when I was doing it, seemed insane.  But I had no real sources for other information. I had no idea if what I had bought would all work together.

I picked out two Hyundai Solar - Hyundai 250 Monocrystalline solar panels.   They were supposed to be delivered on a Wednesday.  I had my welder guy lined up to build a steel frame for me over the weekend.  Paint it, and mount in on the van.  Wire’em up in a couple days and leave with The Wife for a week camping the following Tuesday.  Yeah, that was the plan.  It didn’t even seem ridiculous at the time.

It was though.  It didn’t work out that way at all.  Solar panels are too big to come by UPS or Fed-Ex, they have to come by truck.  The order to the trucking companies is supposed to have the phone numbers contained in your amazon account.   I didn’t even know Amazon had my phone number.  In fact they didn’t.  One was to the landline phone in our current house, the other a state and a house ago and the third number I didn’t recognize at all.  The trucking company will only deliver to a residential address if they can call someone on the phone first.  Failing that, they drop a postcard in the mail.  I assumed since I had been tracking these things across the country four days, if someone was at the residence on the day the web site said out for delivery, it would in fact be delivered.  No, that is not the case.

I ordered 250w panels, I got 270w.  Every
watt helps, I guess but there are so many
panels with so many different features.

I gave them an extra day, past the Wednesday deadline but on Friday morning I started trying to track them down.  I started with the Amazon seller, but he was out on vacation until the following Friday.  No, there wasn’t anyone else I could talk to.  I tried the trucking company, but trucking companies don’t seem to offer much customer service to residential customers.  In the end it was about three weeks later before I actually got the panels delivered!

When they did finally show up they were not the panels I ordered.  Very disconcerting since now more than a month had passed since I had ordered them.  I knew my Amazon return options would now be further limited.   Doing a little research on the panels it seemed like the ones I got were at least equivalent if not a little better.  Whew.

Solar is more than just some panels though.  You also need what is called a charge controller.  This unit will actually end up costing you as much or more than the panels if you want maximum efficiency.  There are really two paths to head down with charge controllers.   PWM or MPPT.  The better of the two, MPPT, of course costs quite a bit more, but there are good reasons why they are worth the money.

PWM, or Pulse Width Modulation works with 12 volt batteries and really can only work with 18 volt maximum solar panels any more than 18 volts gets discarded.  For solar panels, this is low voltage.  A basic fact of electricity is the lower the voltage the more of it you will lose going through wire.   You can combat this by using really thick wire, but that is cumbersome.  Also a problem with low voltage panels is, sure they are rated for 18 volts but that is (I think) at 43 degrees F.  If the temperature goes up, the voltage goes down.  Who would think a big black panel sitting in the sun would get warmer than 43?   This drops enough on a really hot day and you won’t have sufficient voltage to charge your batteries.

The solar charge controller with its cover off.

MPPT or Maximum Power Point Tracking on the other hand can accept much higher voltage coming in.  My panels are 39 volts but I have them wired in series so coming into the charge controller I actually have 78 volts total.  With that much higher voltage I am able to get by just fine on #4 gauge wire from the panels to the controller.  My battery system is twelve volts so the MPPT controller can convert the excess voltage into additional amperage to let the batteries charge faster.

PWM systems tend to not be as technically advanced either.  For instance I bumped up to a larger charge controller not because I needed the solar capacity but the one I got has a built in ethernet port.  I will be able to tie it into my network in the van and log how much solar I am receiving.  I have a small computer that has an adapter card in it with a compass, GPS as well as pitch and yaw.  With that information tied to the solar panel charge data I will know what direction to best face the van, where to park it and how much tilt I have.  I will know the best places to park.  But if I didn’t have the full log data from the charge controller I wouldn’t be able to do this.

I bought one other accessory to make this all handier.  A remote control panel for the charge controller so I can see the status of the panels just by pushing a button.  It is really just a subset of the data coming out of the ethernet port but much easier to get the answer to the “How much solar am I getting right now?” question.