The system looks OK, but I think you might want to consider other options, too.
We've had solar
on our Scamp
5er for years, and really appreciate being able to boondock up in most places without having to worry (much) about our battery levels. We've run into two problems over the years, one when we were in Yellowstone in September and had just one 50w solar panel
, which is why we now have two, and when our battery was starting to fail and needed replacement. For us, 100w of solar
seems to really fit the bill.
Now we're rebuilding a smaller trailer, and I've fit it with a polycrystalline panel that's very similar to the one you're looking at, and you might consider some of the things we did as we selected and installed (and are still installing) the system.
First, you need to know and understand the various types of economically available solar panels and what their pluses and minuses are. Briefly, they are:
* Monocrystalline Panels: These are the long-running champions in affordable solar. Per-watt produced they are smaller and lighter than polycrystalline (savings of about 10%) and amporphous (45%) technologies, but they do have drawbacks. First, they are slightly more expensive than the next-best technology (around $0.25 to $0.50 more per watt), have the narrowest optimum angle of sunlight band (+/- 20 to 25 degrees incident angle of sunlight maintains 80% or better of their peak output), and don't produce well in shady locations.
Nevertheless, our Scamp
uses monocrystalline panels, and we are really very happy with them. They've been real champs.
* Polycrystalline panels: Poly panels were the cheaper, lower-performing twin to Mono panels. Until about ten years ago they had the same incident-angle performance as mono panels, but produced 20% less power per square foot and unit of weight
. About ten years ago a new production technology (Q-Cells) came out, boosting that performance to within 10% of Mono panel technology and expanding the peak production incident angle by around 5 degrees. They also perform slightly better in high temperature conditions than mono, though you have to camp in the summer dessert to see that advantage. Their disadvantages are that they are still larger and weigh more per watt than Mono panels, and that can be a real killer for smaller roofs and lower weight
We selected a polycrystalline panel similar to the one you're looking at for our Surfside
(Solar Cell, Solar Panel, Solar PV, Solar Products, Charge Controllers, Solar Trackers
* Amorphous Silicon: The cheapest to produce of the economically available solar technologies, these also have the highest weight and footprint per Watt, about double, of the other two panel types. They used to be 1/3 the cost of the other two technologies, but these days they're only slightly cheaper, and I don't think they're a very practical alternative. Nevertheless, they do have advantages over the other two. First, they'll produce power over a much wider range of incident angles of the sun, so they actually will produce at least some power in shady locations. Second, they have the widest operating temperature range. If you're going to set up camp in Death Valley during the summer, these are your boys. They're frequently available at Harbor Freight for about $100, with a coupon.
Next, you need a mounting system. The important things to think about are, first, you need a solution that can handle freeway speeds without tearing lose from the fiberglass roof of your trailer. Second, it's best to allow air to circulate under your panels so they can cool . . . which makes that tearing lose thing a whole lot more likely.
The little angles that come with the kit you linked to are probably sufficient; just be sure to use big fender washers to secure the bolt inside your trailer to spread the stress. I used a different, home-made mount and reinforced the fiberglass inside the trailer with an extra layer of mat. If I hadn't done the reinforcing, I'd probably use a 2" diameter fender washer for my front two mounting points where wind shear stress is highest.
You need a water-tight way to get the wires from your panel from the outside of your trailer to the inside. I fiberglassed a home-made "junction" box that matches the solar panel
mounts I made and raises the through-way holes for the wires above the trailer roof, and packed them with butyl tape before tightening the matching cap down.
Your solar charge controller is an important part of your system. The one in the kit you linked to is a $20 (on eBay) "pulse wave modulation" (PWM) controller and not a bad choice, but it'll rob you of 20-30 watts of your panel's output. In days past, I would have said that's a a good tradeoff and that it's cheaper to get a second solar panel than it is to get an upgraded Maximum Power Point Tracking (MPPT) controller, which used to cost a boatload. More recently less expensive (and sometimes fraudulent) MPPT controllers have made an appearance, bringing their cost more in-line with their benefit, but you have to be careful. There have been lots of reports of vendors (most of the eBay offerings fit this description) are putting "MPPT" labels on their PWM controllers and hoping you don't know the difference, then requiring you to pay return shipping to China (which costs more than the product) to get your money back if you do, so buyer beware!
I bought mine from a US vendor and disassembled it to make sure it has the component rerquired (a large-ish iron-core coiled transformer) to perform the MPPT function.
MPPT Tracer1210RN Solar Charge Controller Regulator 12/24V INPUT 10A - Amazon.com
Lastly, let's talk other components of your power system, namely your battery and lights
. You want a good battery; I prefer Absorbed Glass Mat (AGM) batteries because they perform well in just about any environment, last longer, have the lowest charging loss of all the economically viable battery alternatives, and are maintainance-free. (Better, but more expensive, are nickel metal hydride and lithium batteries . . . at 5-15 times as much coin.) To keep your battery -- AGM or traditional "flooded" type -- in good shape and get it to last longer I'd suggest getting a BatteryMinder charger, a trickle-charger that prevents battery-killing sulfation from occurring.
And no discussion of solar is complete without pointing out that getting a solar panel system is really only half of the successful boondocking/off-the-grid strategy. The other half is cutting your energy consumption down to the amount of power your panels produce. You may already have done this, but the fastest and most economical way to cut your power consumption is to install LED lights
. Our Scamp
is LED lit, and when all its lights
are turned on (something that only rarely happens), all the LEDs combined use less energy than just two traditional incandescent bulbs, and we do not suffer for it.
Another thing you can do is change to cut your electric consumption is how you stay warm. You can turn the thermostat down by using more sweaters and a thicker sleeping bag or or you can change to a heat source that doesn't have an electric fan, like a Wave 3 catalytic heater or Portable Buddy that don't use electricity at all.
Our Scamp has both the Scamp-original Suburban furnace
and a Wave-3 heater. The Surfside
has an Atwood Everest heater that uses a third less electricity compared to the Suburban and has room for a Wave-3 if we decide we still want that option.
(My wife, Lynne -- Hi Sweetie! -- probably just learned about that "has room for a Wave-3" thing just now. She's not a fan because the Wave-3 can deplete the oxygen
in your trailer and kill you if you don't have enough ventilation. The Portable Buddy system does not have that problem, but those are topics for a whole different thread.)
Hope this helps.