Considering 100 watt folding Solar Panel

[adamis]

I need to add some more solar to my setup as my current panel just isn't enough to keep the batteries topped off. Having a fiberglass roof, I'm hesitant to drill holes into it to mount another solar panel at this time.

I'm thinking about going with a 100w folding then film panel that I can keep stored inside until I'm ready to setup camp and then set it up on the roof for use. Aside from the minor hassle of having to put it up each time, it seems like a viable alternative to a permanent mount. Amazon has one I'm looking into.

Anyone have something similar?

[adamis]

3 tons wrote:

adamis wrote:
Hadn't considered the wind but I think I could overcome that or do as others suggested and just leave it on the ground. Velcro isn't that bad of an idea either.

I already have a 30amp charge controller in place I was going to tie this into. I have wires already going to the roof for the smaller 20watt panel that I already up-sized them for larger current in anticipation of going to larger panels in the future.

When mixing various panels, one thing to consider is to try to ensure that voltages are the same or close together as possible, else the higher voltage panel will default to the lower panels output voltage. In my case, I have six panels (for 440w) worth 24 rooftop penetrations and with caulking have had no adverse effects...The routine harvesting of adequate (even surplus...) amounts of power has never been a problem...Reliable AC power is provided by a 2000w pure sine inverter-charger...

Best Regards,

3 tons

Thanks 3 Tons!

[3_tons]

adamis wrote:
Hadn't considered the wind but I think I could overcome that or do as others suggested and just leave it on the ground. Velcro isn't that bad of an idea either.

I already have a 30amp charge controller in place I was going to tie this into. I have wires already going to the roof for the smaller 20watt panel that I already up-sized them for larger current in anticipation of going to larger panels in the future.

When mixing various panels, one thing to consider is to try to ensure that voltages are the same or close together as possible, else the higher voltage panel will default to the lower panels output voltage. In my case, I have six panels (for 440w) worth 24 rooftop penetrations and with caulking have had no adverse effects...The routine harvesting of adequate (even surplus...) amounts of power has never been a problem...Reliable AC power is provided by a 2000w pure sine inverter-charger...

Best Regards,

3 tons

[beachbum2011]

I mounted two 100 watt Renogy solar panels no screws required.
I used combination of Sticky Feet mounting brackets and home made brackets.
All held down with 3M VHB tape.
The gelcoat will fail before this tape fails.
Covered brackets with Dicor self leveling sealant.
They have held tight for 25,000 miles .
And nobody can walk off with them.

[profdant139]

For whatever it is worth, all I have is a 120 watt folding panel -- it takes a couple of minutes to deploy and store. In sunny weather, it is more than adequate for our entire power load. (We are careful with power usage.)

Since we usually park the trailer in the shade, I added a long ten gauge cord so that I can put the panel in the sun.

[loggenrock]

I also use the Renogy 100W "suitcase" set-up. Works great - I have a (2) group 27's, and it keeps them fully charged, even when running Fantastic Fan for hours, LED lights, charging cell phones, etc. Shade is a real issue in the East ( we have trees....!)- so I made a 50' extension cord for them from low-voltage outside lighting wire. So despite doing everything wrong (charge controller at the panel, too long a wire run, etc) they work great, meet my needs, and I can move them to sunny spots as the shade moves over the course of the day. To each their own!

[mbloof]

free radical wrote:

mbloof wrote:
I just used stick on solar pannels on my roof:



68W per roll x2 = 136W

How long ago was this?
Ive heard that solar panels need air space below them for cooling otherwise they may overheat and have reduced charging capacity or even fail..

It has been ~4yrs. These panels were designed to stick between the slats of a metal roof. Still works great! No holes or chance they will get 'caught' by branches and low profile.

Other than they never will come off what is not to like?

- Mark0.

[free_radical]

mbloof wrote:
I just used stick on solar pannels on my roof:



68W per roll x2 = 136W

How long ago was this?
Ive heard that solar panels need air space below them for cooling otherwise they may overheat and have reduced charging capacity or even fail..

[time2roll]

The Li battery will harvest more power as it has no long absorption phase of charging.
May not need the portable supplement at all if you go Li.

[2oldman]

adamis wrote:
I don't really need a massive solar array and would actually rather put more money into a LiFePo battery.

My hesitancy for using some of the tapes and glues at this point is I am not certain where I might place the larger panels until I'm ready to take on the project and I don't want to add stuff I might struggle to remove later.

I do like mbloof's stick on solar panel option. Looks really clean.

Lifepo.. now you're talking!

Yeah, tapes and glue can get really messy later on. I wouldn't get too worried about roof holes. Plenty of ways to seal them up, and I'm sure you have some up there already. Then again my roof is rubber, not fglass.

Stick on panels are easy, but it gets really hot underneath.

[adamis]

Thanks for all the tips folks. Right now this is more of a temporary solution. I realize I could just screw the thing in and use the right sealants and tape for a permanent solution. However, my use pattern is such that I spend more time on the road usually and seldom in one place for more than a few days. I don't really need a massive solar array and would actually rather put more money into a LiFePo battery.

If I do upgrade my panels in the future my thought is likely to remove the smaller existing panel, seal up those mounting holes and have some mounting brackets glassed onto the roof that will give me more options without holes penetrating through.

My hesitancy for using some of the tapes and glues at this point is I am not certain where I might place the larger panels until I'm ready to take on the project and I don't want to add stuff I might struggle to remove later.

I do like mbloof's stick on solar panel option. Looks really clean.

[mbloof]

I just used stick on solar pannels on my roof:



68W per roll x2 = 136W

[time2roll]

Plenty of posts of people using a very strong double sided tape if you have a solid roof surface to mount.
I don't have any link to the actual tape used.

[RV_daytrader]

Or you can buy the portable suitcase, park in the shade and put the solar panel in the sun! I have one and it takes all of 3 minutes to set up!

[RoyB]

You will only get some 5 AMPS or so of DC current when in high sun... Battery Science says you need 14.4VDC at 17-20AMPS of DC Current available to get a 50% charge state Battery to its 90% charge state for each battery you have and this will take some three hours of charge time...

Only having 5AMPS available only when you are in high sun will take a long time to do this so it really is just a top-off thing is all you can expect...

I used to use a 10-watt panel on the dash of my truck to keep a top-off going during the day on a bad truck start battery. I nursed the battery for another year doing this....

It really helped out while I was driving MS DAISY around shopping and all as I could sit in my truck and listen to my Internet based Radio Scanner... The 10 watt panel would just barely replace what I was pulling using my cellphone plugged into a 12V socket... I was tickled pink to keep my failing truck start battery at the 12.2-12.4VDC range hehe... My backup of course was always having my 2KW generator mounted in the truck bed area and I could start that up and run a 10AMP Battery charger and get enough juice to start my truck if I ran it down... I could do this for about five minute of charge and then could start the truck... Nice to have a plan B for sure...

Roy Ken