Solar Panels - Planning the Right Choice

[Southbound]

So I`ve been looking through all the different types of solar panels available and trying to figure out what works best. I don`t feel comfortable drilling holes in the roof. Then again, the flexible panels with glue on the back are too long for the roof. I believe I only have 83 inches square and the panels are 110 inches long. I live in an area that is experiencing quite a bit of summer cloud-cover over the past 2 summers and all-winter cloud-cover so choosing a panel that works under cloudcover or shade is important. Uni-Solar is the product-line I`ve been looking at. I`ll be headed to Mexico for winter in my 89 Chevy Fiesta van but I`m not sure what I should be looking at for wattage for boondocking. Any thoughts?

[markopolo]

I'm not familiar with the solar panel brands and specifications to recommend a panel - someone else here will know more. I'll comment on the holes in the roof and mounting instead.

My concern with the stick on panels is heat. Panels get warm and they will transmit that heat into the van. Raising the panels up off the van roof by an inch or so should eliminate the heat transference and actually create shady spots under the panels. That is just my opinion, comments are welcome.

I'd choose holes in the roof over glue. A fastener known as a "well nut" works great for mounting solar panel brackets.

They expand when you tighten them. I cover the well nut and the bracket foot with a sealant like Dicor. Dicor will work on fiberglass as long as the fiberglass is really cleaned well prior to using the sealant.

Consider making or buying a solar panel mount that lets you tilt the panel to meet the angle of the sun. You might only use the tilt when you want to clean the roof under the panel but it is still worth it.
Link: http://www.classbforum.com/phpBB2/vi...ar+mount#p2606



80 watts of panels should be able to maintain your batteries and let you run the roof fan on low off the surplus output all day when it is sunny. My van looks to have about 120 watts of panels, an 80 and a 40. It is more than I need.

If you plan to run TV's and computers all day then you'll need more wattage.

[LesM]

I agree with Marcopolo. I've had a panel bolted to the roof of my Pleasure Way for the last couple of years, and it's seen many miles on the road, without any problems. Check out http://www.carmanah.com/go-power for their system alternatives and sizing (power) info. I have an 85 watt panel flat mounted on the roof and its been perfectly adequate for my needs - basically ensuring my lights don't go out, the furnace doesn't quit on me, and the ceiling fan continues to run. The battery will obviously lose charge at night with the lights and fan running, but I know the next day it will recharge very nicely. Plus on the road, with the fridge on DC, I don't worry about draining the battery when I stop for half an hour and forget to turn the fridge off. No, it won't handle the microwave (inverter limitation anyway) or the A/C, but that's not a concern to me. It's also nice not to worry whether the battery needs charging when I put it into/take it out of winter storage. The solar charger panel manages power flow to the (AGM) battery so I never worry about overcharging. It's pretty much a maintenance and worry free system.

Les

[Southbound]

Thanks markopolo & LesM! I've emailed carmanah a few days ago for a guestimate but no response yet. I'm wondering if I should be getting quotes from Phoenix and having it done there before crossing the border. Ya think it would be cheaper? I'm also looking at switching some of the lights out for LED's. I found a good thread about that already on here but finding the right fitting lights is my issue at the moment. There's surprising little roof space for panels as most of the roof is ribbed with the large air conditioner. Being on such a tight budget doesn't help either. Just having enough power in the night for running the water pump & a bit of lighting is what I'm hoping to achieve during a week long boondocking. The van itself seems to be well built and in good shape but I'm always conscious of the age and fiberglass becomes brittle with age.

[markopolo]

Solar panels will most likely cost less in the US. The last time I bought panels (probably 200 I got them for $4 per watt but they were used. You should be able to do better than that.

Other that the LED light bulbs I made I have always bought LED light bulbs from eBay sellers.


Here's an another option: You can find battery operated LED lights at Dollar Stores. Yes, you have to replace batteries but the lights cost $1 to $2. Hard to beat that. Get one with lots of LED's.

I bought this one at Canadian Tire for $7.99 4 years ago:







I have seen almost the identical light at Dollar Stores.

I mounted it with two short screws through the back under the upper kitchen cupboards in my van for extra light.