Solar Diy Panels

solar diy panels

How do you mount a solar panel to the roof of a motor home?

I just bought a 100Watt PV panel and was curious how this is done. I don’t want it flying off the roof when I’m going 75MPH down the freeway. I also don’t want to pay $100 for a few pieces of aluminum. Some of those mount prices are highway robbery! Am I supposed to put a board under the panel for strength? They seem very fragile. I’d appreciate your help. Thanks for reading.

Well, you can try to improvise something, and if you fail your $500 solar panel is going to fly off your RV like a kite, potentially decapitating someone behind you and resulting in a criminal negligence lawsuit that might bankrupt you for the rest of your life.

Or you can spend the $100 for the manufacturer-recommended mounting brackets, then have it professionally installed, and rest easy. The $100 is not just for the materials, but the design and testing to ensure it is safe, and the liability in case it does fail.

I’m not saying its impossible to come up with a good DIY mounting system. But if you have to ask, maybe you’re better off going with a professional installation?

If not, at least do us the courtesy of posting a link to your rig so we know when to watch out for flying solar panels. ­čÖé

My first DIY solar panel


Solar Power Dvd

solar power dvd

What wattage solar panel do I need?

Considering a solar setup to run three 7 watt CFL bulbs and occasionally 13 watt flood. Lights would run less than 1 hour per day 99% of the time. Plan to use 12V battery and 400 watt inverter. What size panel would be sufficient to keep the battery charged, and what amp battery should I use? Thanks.

Hey Rvnge, this should be a pretty easy setup, but you need a few more numbers to finish designing it. Your inverter is fine for this, I’ve been running CF lights in barns up here for years on cheap 750 watt inverters from the auto parts stores, truck stops and Home Depot. They all put out a cheap modified sine wave signal, and in 7 years, I’ve not changed a single light bulb. Just the same, when you get it hooked up, try a couple different brands of bulbs as you go forward, you might find some give you better light, less flicker, or last even longer.

The big question I have is what is the amp hour rating of the battery. The reason this is important has to do with selecting the panel and possibly a charge controller. Charge controllers do 2 things for you. First, they keep the battery from being overcharged on long sunny days, and second, they keep the battery from backfeeding the panel at night. Virtually all commercially available panels today have diodes built into the junction box, which is designed to keep the current from feeding backwards, so that problem is solved with a 79 cent diode. As far as overcharging, there is a rule of thumb that says if your panels maximum current is less than 2% of the battery’s amp hour capacity, then you don’t need a charge controller. You can read about this in Richard Perez’s book at the library, I’ll list it below. Less than 2% is considered by battery manufacturers as a trickle rate, and a flooded lead acid battery can absorb this continuously, in fact, it’s good for them, particularly the deep cycle type.

If you have something like a marine trolling battery, it might be rated at 60 to 80 amp hours. Taking 2% of that gives you about 1.5 amps as a maximum trickle rate. Panels are generally wired for 18 volts to charge a 12 volt battery, so 18 volts X 1.5 amps gives you a maximum panel size of 27 watts for that battery. You can use a bigger panel, but you’ll need a charge controller. If you decide to go that route, get one that is several times larger than you need. As an example, say you decide on a 75 watt panel, which has a maximum current rating of 4.1 amps (75 / 18volts = 4.1), I would suggest a 10 amp controller. They don’t cost much more, maybe $80 for a good quality one, but then you can add more panels later, and the controller will last longer if you are not pushing it to its limit. In a solar battery charging setup, the controller is always the first thing that fails, so it is worth oversizing.

Looking at your load, say you run 21 watts of lights for 1 hour each day, plus the flood for another 15 minutes. That gives you a total of 25 watt hours. Add another third for the inverter losses and another 10 percent for the battery losses, and you’ll need at least 35 watt hours per day of solar. In this case, that 27 watt panel is just enough using a mean average of 2 to 3 hours of sun per day.

Have you bought any equipment yet? If it were me, I’d do the same thing we did in our neighbors barn 3 years ago. Go with 2 golf cart batteries instead of one 12 volt. Trojan makes the best, the model T-105. You need 2 because they are 6 volts each. But wiring a pair in series will give you a 12 volt 220 amp hour battery pack. Now you can use a panel as large as 80 watts. You can skip the controller, and use the money saved for the batteries, then you’ll have power for several hours of light several nights in a row, or even the occasional small appliance, like a drill, radio or portable DVD player. Just make sure you put distilled water in those batteries regularly, like once a month in warm weather, once each season if it’s cool.

We’ve been powering our home with the wind and sun for 11 years now, and I’ve probably wired up half a dozen little remote cabin systems like this. “J” has a point you should consider too, what about low voltage lighting? There are some 12 volt small flourescent stick lights and things like that at the truck stops or RV places, or for a few dollars more, LED has some great promise, they never burn out and are hiddeously efficient, about 3 times more than CF even, and then you don’t need the inverter, but you could have one on hand anyway for bigger lights and stuff. Good luck, and take care, Rudydoo

solar power dvd 1st part


Solar Diy

solar diy

How to install solar film on windows? Did you face any problems?

I’m planning to buy solar films from the local DIY shop to install on my residential windows. For those who have done it, did you encounter problems? What exactly needs to be done to install them properly? If i screw up while doing it, can it be removed without damaging the windows permanently?

Go to and read there. I have installed on several house windows and very happy with results. The biggest thing is getting the windows clean beforehand and keeping them clean during the installation. Lots of fluid sprayed front and back of the film. Do it on a cool window. Window cannot have any cracks or signs of stress like a shot from a BB or it will crack worse with heat. Some films can come off easier than others.


Solar Diy Projects

solar diy projects

How to make my camper green?

I am building my own camper right now. While I’m still in the building process what are some ways that I can effectively build wind or solar generators to power most of the electricity? I’ve searched the web and I just can’t find any good DIY (Do It Yourself) projects for them. Thanks!

some recycling bins and a lot of green paint.

Broken LCD to Solar Panel recycling green DIY Project Part 1