Panels - portable vs mounted?

[tentcamper]

We replaced all the lights in our TM with LED's, including removing the bathroom light and replacing it with a fixture like the rest of the lights except it has 2 bulbs, which I install one bright bulb like the rest of the bulbs and a dimmer bulb for late night visits,

We just got our first solar panel, a 80W potable panel. I was not sure about portable vs perm. I finally decided on the portable since the only time I need it is when we are camping in the cold months. Where we normally can get 2-3 nights off a charge. But if in the future I want to mount the panels, I can because they are the same as the perm panels.

I would be interested in why you are mounting your panels? I think I had read one of your posts from several years ago about your portable panes and that influenced me a little. I think it was the flexibility to position the panels in the sun that made sense.

[scrubjaysnest]

Originally Posted by tentcamper

...............snip....................

I would be interested in why you are mounting your panels? I think I had read one of your posts from several years ago about your portable panes and that influenced me a little. I think it was the flexibility to position the panels in the sun that made sense.

What I am looking at doing is mounting two panels, similar to what HarveyRv did. In addition I am looking at picking up a 140 watt panel, that will be about 8 additional amps when all three panels are in the sun. I may have the 140 watt as a portable or roof mount it and keep the two 80 watt panels portable. One of the things I noted this summer is with full sun We are right at the ragged edge of getting full charge on the new batteries even with our light loads. One of the things that has saved us in the past is moving the camper every few days in which case I don't set up the panels.
In your area during the winter months getting enough sun even with two 80 watt panels probably won't happen.
The further north one gets the worse it gets.
I plan on monitoring things closely while out west this winter, AZ gets better sun in winter then we see in summer when looking at the insolation values.

[Bill]

There are two big arguments against permanently mounting the panels. The first is that if they are permanently mounted on the roof, then they are mounted FLAT, and flat is never the best mounting angle. In order to get maximum benefit from the sun, the panels should be tilted to meet the sun straight on.

The second argument against permanent mounting is that you need to park your camper in the sun. If you park it in the shade, which most of us do, then the amount of power they can generate is seriously compromised.

On the other hand, the benefit of permanent mounting is the no-effort setup, and that the panels are hard to steal.

I have often thought that if you want to permanently mount the panels, then success can be assured by installing excess capacity. If you truly need 150 watts, then the best solution may be to buy 300 watts worth of panels, and accept the fact that you won't be getting 300 watts out of them very often. Years ago, this approach would have brought gasps of horror from people. But solar panels are getting cheap enough that it is becoming an easy and practical solution.

The more I think about it, Scrubjay's hybrid approach - some mounted and some portable - makes a lot of sense. If the mounted panels can do the job on any given day, then things are simple. If they aren't quite meeting the need, then bring out the portable.

Bill

[tentcamper]

I'm hoping to extend my time between charges in the cold months. I would like to take the 2-3 days between charges to 4+. Dear wife gets worried when I want to go 2 nights. It all go's back to some camping years ago and having the furnace stopping at 2:00 AM and it was 20 degrees outside. The last few years, it's like she wants me to recharge every day.

Our camping, we are not anywhere longer then 4 nights with the norm of 3 nights. Than we move on or head home. So i'm just looking to push the battery a day or two, not to fully recharge every day. Recharge between CS's or at home.

Yes, i'm a little farther north. Everything I read indicates on the conservative side; I should plan the average day solar charge of 3 hours in the winter and 4.5 in the summer. I think on the shortest day the sun angle is like 55 degrees and the longest day it's like 25 degrees.

I liked how HarveyRv did his panels. I think that it is about best I have seen for installing the panels. The big plus with the perm panels would be that they assist the recharging during travel.

[scrubjaysnest]

We will be experimenting some in December, I can't say the rule of thumb to adjust the panels to the same angle as your latitude makes any difference I could see. This summer in MI they were propped on the roof with a 2x6's and handled the wind gusts without problem but something more secure would be better. I'm thinking aluminum angle bolted to the panels may work. Set them on the roof(back shell) then open the back shell. Try to avoid ladder time here

[funpilot]

Here are some interesting discussions on tracking the sun:

http://www.irv2.com/forums/f56/1-kw-...rv-167098.html

If I ever put solar on my TM, it will be one of these as automatic tracking is heavy and too expensive for me. I buy into it is cheaper to add more panels than to worry about tracking and theft:

http://www.gonewiththewynns.com/flex...olar-panels-rv

[tentcamper]

"Same angle as your latitude". scrubjaysnest, we must have read the same thing? I also read that is the base line, with the sun being 15 degrees higher on the longest day of the year, and 15 degrees lower than the baseline for the shortest day. My latitude is about 39 degrees, so for spring and fall I will add some short pieces of PVC pipe to the legs to make it about 48 degrees. Otherwise they are 30 degrees.

funpilot, Just getting started with solar here. We are very good at conserving our power. Here are my thoughts; I have lived for 25 plus years without solar and almost never carry the generator. But most of our camping is 3 days at any CS and we recharge between CS or move on to a CS with electric. There are only a few times a year that we need to recharge with the TV or a generator and that is during cold nights of the spring and fall. So just like the generator, I don't want to haul solar all the time and I will not bring the generator.

But maybe after a year or so, I will add panels to the trailer if the potable thing does not work well? Or maybe go to scrubjaysnest hybrid idea?? Solar is cheap now compared to what they were 5-10 years ago.

[scrubjaysnest]

I plan on taking the aluminum angle with us to set the panels on the TM roof. Nothing will be attached to the camper and the panels will be set for 30 degrees. I'll also have the pvc stands we normally carry. Most of the time the panels can be placed on the ground and get good sun but sometimes it is better on the TM to avoid shadows. Just need something more stable then 2x6's.

[Lesherp]

After a lot of consideration I ended up mounting my panel so they could be tilted on the TM if needed or removed to become portable. The problem with portable is you get no gain when traveling. I wanted this because I have not solved the battery drain from the refrigerator. We had camped at a number of sites with very limited sun but my panel had always managed to keep us charged without tilting or removing. Up until this last trip I had begun to wonder if I had wasted a lot of effort and some money for nothing. The panel had been so successful last year I didn’t bother to bring the generator on the trip this year.

When we got to Acadia NP we camped in Blackwoods Campground and had a sliver of sunshine when it wasn’t cloudy. Blackwoods is appropriately named. Without the option of removing my panel it would have been worthless. I think we were there for 5 days and I managed to keep the batteries reasonably charged. I figured out where the best sliver of sun would be and placed the panel there and did not attempt to chase it as we were off hiking or biking. I think there were only 2 sunny days but the panel boosted me up some even on the cloudy days. Each day I would have slightly less battery than the day before but never fell below 50%.

This turned out to be a rather long thread but it kind of walks you through my how my solar instillation went if anyone is interested.

http://trailmanorowners.com/forum/sh...ad.php?t=13865

[Padgett]

Today 28 Nov Renogy is having one of their periodic sales, essentially 10% off and free shipping for most.

I just ordered a second 100W panel.