Where to mount solar panels on roof?

The new thin flexible panels do look nice. I sure thought about using them on my roof, but I read a couple concerns about if they could be glued to the roof.. heat buildup and some cupping in some of the early testers. I decided to stick with the traditional panels.

For me having them up on the roof working while driving down the road and basically being installed and forgot outweighed using any portable and worrying if they might walk away.

I do see where if you camp in heavy shade or want to chase the sun, a couple portable panels could work for you.

You have to be specific about leaving them flat and just adding an extra flat panel to be equivalent to tilting them.

Actual numbers: 130w panel daily AH haul 49.3N, mid May:
Flat 56, Tilted 70, Tilted and tracking 90

So we see that adding a second 130w both flat would be 112AH, more than the single tracker at 90, BUT

What about two 100s tilted but now you lay them flat and add a third 100 flat? Be the same as the 130w tilted but now flat and add a flat 65w in proportion, so:

130w tilted- 70
130 + 65 flat- 56 + 28 = 84

So that works too, but you see that the "extra panel" must be enough addition to the original set to make that break even or better. EG

Say we started with two 130s tilted - 140AH
and now laid them flat and added a flat 65, we get:

112 + 28 = 140 so breaks even. So anything less than adding 1/4 of the original tilted will not break even (at 49.3N in mid May)

So you could take your two tilted 100s and lay them flat, add a flat 50 and break even

My 2 100 watt panels got used as portable the first time I took them out and like the guys in the know say it’s not worth the hassle of storing them in the trailer, stringing out 40 foot of cord then drying them off before putting them away on a wet day. I’m going with the theory of figure out how much you need then add an extra panel and don’t worry about it as the extra panel will help make up for shaded panels. I do see the benefit of portable so I might make up a folding suitcase portable out of 2 50 watt panels so it’s a little easier to deal with but not 2 100 watt panels. There’s no way I’m going to spend the $ on a portable set up when I can get panels for half the price and make my own.

That's why there is a big selection of panels out there,.... because we all have different ideas. I started out thinking portable was the only way to go, but din't take long to change my mind on that,.....just too much hassle !
And if I feel like parkin in the shade, not a big deal,.....that's only one reason why I still have my little Honda,.....another being solar don't work in the rain.
Flexable panels,....kinda like AGMs, got a long way to go on price !

vermilye wrote:

Interesting, but I purchased he same folding panel kit from Solar Blvd for $235.00. Unfortunately, they no longer seem to carry it.

I think you can call them and ask for it.

Harry1954 wrote:
If you park under a tree or in the shade the solar will not perform as well. Why not get a folding set like these ones

http://itechworld.com/collections/solar/products/folding-solar-panel-kit-160-watt

I am trying to work out if I should fix the panels or get a folding set that I can move around the trailer and chase the sun. The little kits look like they are only good for charging a phone.

Interesting, but I purchased he same folding panel kit from Solar Blvd for $235.00. Unfortunately, they no longer seem to carry it.

Niner Bikes that looks like a great set up. I think I need some more power so I am going to get the 160W I think.
I cant believe the price on some of this stuff so I think I will go middle of the road with iTechworld.

Hi,

Here is a foldable:

http://www.okorder.com/p/factory-direct-wholesale-price-foldable-120w-solar-charger-mobile-solar-charger-for-smartphone-tablet-pc-laptop_313267.html

All here is a discount code for www.itechworld.com that we found. Z5VJZXC27DKU

I also looked at the Goal Zero foldables, but passed because of the price. FYI, read the specs carefully because some of the models are glass-faced and no lighter than a normal panel.

If you are camping in an RV then you can do better on both price and performance by purchasing separate components, rather than a kit. I have a TT and a tent and I bought the Goal Zero Yeti 400 and the smaller one for the tent, so that I could have one discrete, portable unit, rather than a lot of stuff to deal with. As it is I ended up adding two more batteries to the 400 and an external charger, so I have more stuff anyway.

Back to the Renogy bendable: They are actually just somwhat "floppy", not overly flexible. One support in the middle and they can be tilted to the sun and easily turned to face the sun all day long. This is where the major efficiency gains are found, IMO.

As for cost per watt, I suspect my $2/watt panels are in fact cheaper than $1/watt (or less) panels, because of the increased sun time through repositioning.