movable solar panels/built in system?

noteven wrote:
In December I see about 25-30% output increase with my little Renogy 100w suitcase kit flat vs tilted. This was at the north end of Lake Mead, NV

that is pretty much what I would expect.

An excellent way to "aim" a panel is to take a short tube (like an empty toilet paper tube), and place it upright on the panel. orient the tube for no shadow. that is the optimal tilt in the "x" and "y" directions. That places the sun exactly perpendicular to the panel.

In December I see about 25-30% output increase with my little Renogy 100w suitcase kit flat vs tilted. This was at the north end of Lake Mead, NV

There is no way on God's Green Earth that I'm going to climb to the roof to stow the panels during a storm. The only way I'd consider it is if I had actuators.

If I went to awning type--that would work because I could stand on the ground. However, as my width is 102" which is the legal maximum, I can't do that, either.

CA Traveler wrote:
The 30% improvement mentioned above seems reasonable to me. Why when I don't tilt? My CC will record various parameters and I've noted the differences when the sun changes from Jan to July with clear skys.

Some of the tilting value for RV panels may be confused with a fixed install say on a home roof. In that case the tilt angle is not as significant when measured for year round power production as the sun does the tilting - err elevation changes. Actually the sun doesn't change but the earth axis does.

and a fixed roof home install already has the panels tilted. the typical 4/12 roof pitch is a pretty good tilt angle for much of north america. they aren't tracking,but at least are tilted.

I have two 100 watt (23% efficient)portable solar panels that I use.. There light weight and easy to move around and they ride on the top bed in my truck camper..

The 30% improvement mentioned above seems reasonable to me. Why when I don't tilt? My CC will record various parameters and I've noted the differences when the sun changes from Jan to July with clear skys.

Some of the tilting value for RV panels may be confused with a fixed install say on a home roof. In that case the tilt angle is not as significant when measured for year round power production as the sun does the tilting - err elevation changes. Actually the sun doesn't change but the earth axis does.

I decided that 500W would be enough so I added a 3rd panel and mounted them flat. Works for me.

I read that the average number of tilts for panels on a MH roof is 7. I could add tilting hardware but so far my average is 0 tilts.

pianotuna wrote:
ktmrfs,

I'd love to get fancy and add actuators to solar on my roof. Or at least on the sides of the RV. Of course doing so is ruinously expensive.

what I did on mine is each of the 3 panels can be oriented in one elevated different direction. Not as good as all 3 optimum, but at least one can be closer to optimum.

to do that I used the brackets from AM solar in eugene oregon. they have mounting brackets with T knobs and extension tilt bars. Lets you orient at about a 45 degree angle.

Means crawling up on the roof, but if we are camped for a few days or a week or more it's worth the effort to tilt.

I suspect the mounts could be modified for the ones on the side of the trailer to tilt them upward away from 90 degrees more towards 45 degrees or so.

ktmrfs,

I'd love to get fancy and add actuators to solar on my roof. Or at least on the sides of the RV. Of course doing so is ruinously expensive.

wintersun wrote:
Tilting panels does not result in much gain unless you are in Canada and even then it is trivial most of the time. The panels are designed to work with sunlight coming into the cells at an oblique angle.

With them mounted on the roof you get charging 100% of the time, whether driving down the road or parked at a rest stop or when the RV is being stored. The most difficult part of the installation is running the large gauge cables from the solar charge controller to the batteries.

ummmmmm don't even need to go to canada. In the spring or fall in oregon, tilted vs flat panels can mean a difference of 30% or more in current. max power is related to the sine of the angle difference between the panel and the sun.

I have 6 identical panels. 3 roof mounted 160W panels and 3 portable panels, in spring and fall tilting two of the portables aligned with the sun around noon consistently outperform the 3 rooftop panels all day long. Middle of the summer the difference isn't as great but is still noticeable.



yes, roof mounted panels do charge while driving down the road an advantage. But then you have to park in the sun while camping to get the benefit, which can be a downside.

neither is the perfect solution.