installing solar panel on trailer questions..

[carl2591]

I am looking to install solar panel on my airstream and was looking at some 195 watt 24 volts units. They are a bit larger than the 100 to 130 watt 12v version and i was wondering if the size would be an issue, especially when going down the road, with maybe causing the frame to flex to much and crack the panels etc.

the panels size is 63 tall 32 wide and 1 1/2 thick on the frame.

has anyone else used the larger panels?? I was planning to use feet to mount to top on 32 wide side so the panels can be tilted either way. THere would be no support on the long side more or less.

any input on is this might be a issue would be appreciated especially from folks using larger panels.

[carl2591]

I have been to jacks site along with handy bobs blog and read everything several times. Right now the RV is fitted with 2-12v 100 AH? batteries, not sure the exact type as we have not picked up the trailer from PO yet.

I do want to use 6v golf cart batteries the 225 AH t-105s or equivalent, and looking at the tristar 30 -45 amp MPPT model and an upgrade to the 50amp inverter on a 2005 airstream at some point.

the file show I was not able to open for some reason.

westend wrote:
The first consideration when thinking of solar power and and an RV is your daily use. You should do an energy audit and also assess any future use.

Here is a special calculator that will help define your power use.

Another consideration is the size of your battery bank. The amount of wattage will be influenced by that.

About tilting: Ask yourself how often you will be willing to get onto the roof of your RV to tilt and then untilt your modules for transportation. It is often easier to just add another module to reclaim the difference in harvest.

About mounting, hardware, and wiring: Solar modules do best when allowed at least 1 1/2" of clearance on the underside to dissipate heat. There are mounting holes, typically, formed in the frame. Using a piece of angle material mounted into those holes and another angle piece mounted to the RV is a good solution as it provides the clearance and makes installation/deinstallation much easier.

Wire size shouldn't be a consideration. Use the largest possible size available since cost is insignificant and you will reap the benefit of larger wire for the life of the installation.

You haven't mentioned controllers, yet. It is an important part of the system and budget. What type of module you choose, will dictate the type and size of the controller.

There are many active solar users in the Tech Issues section of the Forum. Answers and help are readily available there.

Here is a good link to help educate yourself about solar and RV's: Golden Rules of Solar

[time2roll]

Bouncing down a potholed dirt road will rip your suspension off long before the solar panel is damaged.

I think that installer may not be prepared to use high voltage DC and MPPT controllers. Mine runs 90 to 100 volts in normal conditions. More caution is definitely needed as you get over 50 volts.

[westend]

The first consideration when thinking of solar power and and an RV is your daily use. You should do an energy audit and also assess any future use.

Here is a special calculator that will help define your power use.

Another consideration is the size of your battery bank. The amount of wattage will be influenced by that.

About tilting: Ask yourself how often you will be willing to get onto the roof of your RV to tilt and then untilt your modules for transportation. It is often easier to just add another module to reclaim the difference in harvest.

About mounting, hardware, and wiring: Solar modules do best when allowed at least 1 1/2" of clearance on the underside to dissipate heat. There are mounting holes, typically, formed in the frame. Using a piece of angle material mounted into those holes and another angle piece mounted to the RV is a good solution as it provides the clearance and makes installation/deinstallation much easier.

Wire size shouldn't be a consideration. Use the largest possible size available since cost is insignificant and you will reap the benefit of larger wire for the life of the installation.

You haven't mentioned controllers, yet. It is an important part of the system and budget. What type of module you choose, will dictate the type and size of the controller.

There are many active solar users in the Tech Issues section of the Forum. Answers and help are readily available there.

Here is a good link to help educate yourself about solar and RV's: Golden Rules of Solar

[carl2591]

Not so much wind damage but more damage from bouncing as a RV does going down the road.. on the airforums a guys the does a bunch of solar installs was saying they did not use the larger panels due to the excessive flexing of the frame causing the glass to crack delaminate\etc and other problems..

I was more intrested in panels with a 24v output vs 12 to keep wiring size and weight down. seem most of the smaller 100-150 watt units are 12v. I did find some that are 195 watt and the size is not too big. they are Length 62.3"; Width 31.9", Depth 1.6"

I do appreciate all the info and first hand experiences.. Plus I was thinking you could get some alum bar stock and attach to long side with screws to frame to help stiffen it up.

smkettner wrote:
My 225w panels are broadside to the wind and have survived just fine driving 62 mph into 45 mph gusting wind. I think most of the air goes over the panel or is parallel to the roof causing no lift issues.

what charge controller do you use for your large panels which I am guessing are 24v output.



> Forum Members Solar Installations With Pics

Never seen a post with wind damage or coming loose from the mounts.

[dave54]

carl2591 wrote:
I thought i had heard earlier this year they (congress) did extend the SETC for another 5 yrs? but that might be for large scale projects not home projects. how do you go about getting the credit for the system??

dave54 wrote:
Do it this year.

The Solar Energy Tax Credit is set to expire end of 2016. Maybe Congress will extend, maybe not. I wouldn't count on it.

IRS form 5695.

I had not heard it was extended, only talk. If so post back.

[carl2591]

I thought i had heard earlier this year they (congress) did extend the SETC for another 5 yrs? but that might be for large scale projects not home projects. how do you go about getting the credit for the system??

dave54 wrote:
Do it this year.

The Solar Energy Tax Credit is set to expire end of 2016. Maybe Congress will extend, maybe not. I wouldn't count on it.

[time2roll]

My 225w panels are broadside to the wind and have survived just fine driving 62 mph into 45 mph gusting wind. I think most of the air goes over the panel or is parallel to the roof causing no lift issues.

> Forum Members Solar Installations With Pics

Never seen a post with wind damage or coming loose from the mounts.

[dave54]

Do it this year.

The Solar Energy Tax Credit is set to expire end of 2016. Maybe Congress will extend, maybe not. I wouldn't count on it.

[MikeInOregon]

My 150 watt panel is 58 x 26 x 1 3/8. It is mounted on the roof at the front of the trailer with the feet that are not tilt-able. The assembly seems very stable. I climb on the roof during each camping trip to clean tree debris off of the panel and I haven't noticed any problems.

The only problem we initially had was parking under trees at the campsite and having the panel shaded. We added a 100 watt portable panel that we move around on the ground to follow the sun. This has been a good addition to our solar system.

[carl2591]

if you don't mind my asking how long have they been on the 5er and how much traveling are you doing with it? also what size or watt are they and in 12 or 24v types.

I figured you could take a bit of alum bar stock something say an inch tall by 1/4 and attach down the length of long side, drill and install 5 or so s/s screws with nuts on them and eliminate the flex you might get going down the road.

sound like a no issue to me..

kregli wrote:
I have some panels a bit bigger than that on my 5th wheel and have seen no problems (yet). Mine are fixed with mounting feet on the 4 corners.

[kregli]

I have some panels a bit bigger than that on my 5th wheel and have seen no problems (yet). Mine are fixed with mounting feet on the 4 corners.