Solar for a new Scamp 16

[AliceGardner]

Hi, I purchased a brand new Scamp 16' this past summer and I am wanting to get a solar panel on it over the next few months. I have an RV SOLAR ELECTRIC catalog and design planner booklet and am getting close to being ready to choose a 100 watt system which I could add another panel to later if I want (it looks like I would use 26 or so amp hours/day).

But the thing that bothers me is the best way to fasten it to the fiberglass shell. What's the state of the art on adhesives for something like that? Or other options? I do NOT want to drill holes in my fiberglass shell - I know that much. I'd rather just go with a suitcase setup than do that. I'm still open to recommendations on going with flexible vs rigid panels too. Want to make suggestions either to help with choices, or for who are the experts to consult with on these questions?
Thanks a million,
Alice

[gordon2]

VHB tape is used by some to attach panels or brackets. I will not do it. IMHO if you want to permanently mount panel(s), then bolt them on. The reasons have been discussed before.

Also IMHO, for most people portable panels on a 10-18 foot cable are a much better idea. Ditto on the prior discussions.

I use a 30 amp controller inside the camper with a marine jack. The plug goes to my panels.

Flex panels have a bad track record, are more expensive and the technology is still questionable. But they are much lighter and easier to handle. I have a 50 watt flex panel with 15 feet of 10 gauge cable. I think the cable weighs more than the panel. Its easy to move and adjust it for maximum sun exposure, something not at all easy to do with mounted panel(s).

[Byron Kinnaman]

First question... How long do you intend to camp at one time.
Longer than a 3 or 4 days and solar might be good idea. Week-ends in the summer only, a waste of resources (money and time)

I have mine set up to be portable and I don't get it out anytime during the first 4 days in one spot.

[AliceGardner]

Well, thanks Gordon! If others agree that portable is the best way to go, then that makes this project a lot easier! My battery is the standard deep cycle 27 that came with the Scamp. I'm thinking I'll try a 100 watt solar panel kit that attaches to that battery and learn from there.

On your setup, you must have batteries inside, yes? Am I understanding what you said correctly? I am clueless as to what a marine jack has to do with solar though.

I am thinking to just go with a kit that includes controller and cables and learn from there. Sound like an ok way to go? Any particular company considered particularly reliable for putting together the right combo of parts for folks?

I guess I really should put in some time reading back topics on this forum. There's so much, its a bit daunting.
Alice
Alice

[gordon2]

Yes a Suitcase style where the controller connects to the battery terminals (usually with clips but you could use a quick connect), is a fine way to start and maybe all you will need for occasion use. The biggest downside as I see it is that the controllers are (as a rule) not water proof. The second-most concern is that the controller might not work with other configurations if you change or expand your solar.

No my battery is not inside. The controller is (and thereby protected from the elements). The controller is much like the converter in your trailer except where the converter changes ~120 volts AC to ~12-13 volts DC to charge the battery (and run things) while the solar controller changes the solar panel output (maybe 18-19 volts or so DC) to a similar lower value and adjusts the output according to its battery charging algorithm. So the wiring to the battery on the tongue is similar. Also the solar controller usually is used for charging the battery but not being the exclusive 12 volt power source like the converter can be.

The marine plug is just a way to get the wires through the shell with no leaks from rain, and allow it to be easily unplugged.

Renogy would be my brand unless they were too expensive. The I might take a chance of getting a more inferior product from somewhere else.

[Huck]

I have a flex panel (100 watt) attached with VHB tape and it has worked great for over 3 years. It keeps my batteries charged year round. It keeps you fully charged while traveling. You don't have to lug anything around, hook up, and unhook when you leave.

The only drawback is you probably want to park in the shade (if possible) in the summer. I solved that by buying an additional 100 watt panel that has a 20' cable, so it can be placed in a sunny area. It only requires plugging the cables in rather than having to connect directly to battery. I rarely used it so don't usually even take it with me.

[Seabee]

Originally Posted by AliceGardner

Hi, I purchased a brand new Scamp 16' this past summer and I am wanting to get a solar panel on it over the next few months. I have an RV SOLAR ELECTRIC catalog and design planner booklet and am getting close to being ready to choose a 100 watt system which I could add another panel to later if I want (it looks like I would use 26 or so amp hours/day).

But the thing that bothers me is the best way to fasten it to the fiberglass shell. What's the state of the art on adhesives for something like that? Or other options? I do NOT want to drill holes in my fiberglass shell - I know that much. I'd rather just go with a suitcase setup than do that. I'm still open to recommendations on going with flexible vs rigid panels too. Want to make suggestions either to help with choices, or for who are the experts to consult with on these questions?
Thanks a million,
Alice

the VHB tape is proving itself all over the country......same stuff as what holds most auto trim on....some have had it on for years without failure

[MurrayC]

Make sure the roof will support the load. Weight and wind. They don't seem to be heavy but a lot of roofs are not made for this.
Took mine off of a 1076 Ventura trailer.
Good luck

[DougOlson]

I think starting with a portable system is a good idea. I have a 60W portable that I can use but after a while I got tired of the set up process. I then installed a 120W flex panel on the roof with VHB tape, and I can still use the portable system when I park in the shade.

[gordon2]

Originally Posted by Seabee

the VHB tape is proving itself all over the country......same stuff as what holds most auto trim on....some have had it on for years without failure

And some have not...
Our solar panel blew off!! - Escape Trailer Owners Community

You will need to read most of the 51 pages to get the full picture. Bottom line for me is that it is not worth the risk. (Don't forget the massive wind load that is possible, driving 65 MPH into a 70 MPH gust for example)

I have also used VHB tape for a number of other small things inside my camper. Some have worked well for a few years and counting, some have not. Most failures seem to be caused by the type of surface and / or high temps.

The proper type of VHB tape is required (there are different types for different surfaces and applications). And proper preparation is key. So if you use it for a roof mounted solar panel (which can create signification liability if it fails), I would suggest you read all the technical literature that 3M provides.

Lastly, solar panels (including flex types) work best and last longest when air can circulate under and around them. So putting them flat on the roof is not ideal.

(YMMV)

[John Linck]

I chose to roof mount a 100 watt panel for a couple of reasons. First, I thought storing a portable panel while in transit would be problematic as our 13 and Subaru are smallish. I suppose this would be easier if one chose two 50 watt panels in some kinda case. Second, I go Scamping to hike and be outdoors, not fool around chasing the sun with a theft prone solar panel. My roof mount was/is really just Install it and Forget it. It captures the photons nicely and keeps the battery charged. I just watch the voltmeter. I did oversize it by 2X at 100 watts to make up for its non-tiltablilty, occasional tree branches and Winter's low angle sun since we often travel in Feb/Mar to avoid the worst of Wisconsin's Winter.

Also, the panel maintains the battery during the 9-10 months that we are not on the road. The Scamp sits in our driveway and a portable panel would just get in the way on our crowded inner city lot. With my first Scamp I set a time switch to turn on an hour a day to power the trailer's older model converter while in the driveway. It maintained the battery OK, but it boiled out a bit of water and I was always tripping over the drop cord. Plus I worried a bit about the 120 volt warm converter with its fan possibly failing is some manner and cooking my egg.

I am a little perplexed by folks worried about roof loading. I have climbed around on top of my Scamp on several occasions and though I do lay down some padded plywood panels to distribute my 200 pounds I have not noticed any deflection or sagging of the roof. My 17 pound solar panel, supported on 4 widely distributed brackets, seems a negligible addition.

All that said, I encourage everyone to try solar in any configuration. It really helps us stay longer in beautiful places far from the grid, like the picture below. There are lots of workable solutions and one solution isn't best for everyone.

john

Pic of our solar panel collecting photons at Jumbo Rocks Campground at Joshua Tree National Monument.

[Josh and Sonya W]

Originally Posted by AliceGardner

Well, thanks Gordon! If others agree that portable is the best way to go, then that makes this project a lot easier! My battery is the standard deep cycle 27 that came with the Scamp. I'm thinking I'll try a 100 watt solar panel kit that attaches to that battery and learn from there.

On your setup, you must have batteries inside, yes? Am I understanding what you said correctly? I am clueless as to what a marine jack has to do with solar though.

I am thinking to just go with a kit that includes controller and cables and learn from there. Sound like an ok way to go? Any particular company considered particularly reliable for putting together the right combo of parts for folks?

I guess I really should put in some time reading back topics on this forum. There's so much, its a bit daunting.
Alice
Alice

Hi Alice,

We went through a similar thought process - roof or portable - and decided we couldn't go wrong by starting with a portable, just as you have mentioned. We wanted to avoid "stuff" on the roof, and wanted to get a real feel for our off-grid power needs, before thinking about a permanent install, if necessary.

We have a 25ft Bigfoot, and after doing some calcs, we decided to go with a 160W Zamp, to give us a bit more leeway, in case of shady days, or days when we were away from the site most of the day and were concerned about leaving the panels outside.

The Zamp we got is the newer, more-or-less Made in USA, version. The solar cells, according to Zamp, are the same German cells used by SunPower, and have a 21% conversion efficiency rating, which is about as hight as I've seen. You can read about comparison of efficiency ratings of various solar systems (meant for houses) here:
2017 Most Efficient Solar Panels on the Market | EnergySage

I don't know how to go about testing the actual solar efficiency of our panel, and I have only Zamp's word for it that the cells they use are the same as those found in SunPower panels. Still for me, high efficiency was an important consideration; you'll see in the article that efficiency can range from a low of about 14% to a high (for now) of 21%. I figured I'd rather have one, more expensive, more efficient set (actually two, connected, folding 80W panels that fit into a case), than more panels to provide the same power output.

Zamp is pricey, there are much less expensive portable units on the market. If you are a DIY type person, you can probably assemble your own system for much less.

The 160W unit we have is quite heavy, about 47 pounds, so it is a bit of a pain to set up each day, and to move around if you are chasing the sun between shadows in wooded areas. We did order an extra 15ft extension cable to make it easier to locate the panels in the sun. My guess is that a 100W would be more than enough for one person in a 16ft trailer.

Another thing I liked about the Zamp portable we got is that it was available with a built-in controller that is water proof, and has selectible settings for different types of batteries, including Lithium.

We did a five week, boondocking trip with our Zamp shortly after we got it. Turned out not to be a good test; the battery that came with the trailer was a standard truck/tractor lead-acid battery, that we soon discovered was dying and was not holding or taking a full charge. Still, we managed to "survive" using minimal lighting, as well as the pump and occasional fan. (We don't have TV at home or in the trailer, so that was not a concern.)

Since returning, we found a good but still outrageously priced Relion 300 amp hour lithium battery. The big advantage of the Lithium batteries is that you can drain them down to 20% of their rating, without doing damage. The various types of lead acid batteries, can not be taken down past 50%, without shortening their lives. Lithium batteries are also much lighter; the 300 AH Relion weighs 93 lb, the type 27 estimated 100 AH truck battery we had weighed 67 lb.

I'm not at all suggesting that you change batteries, you should definitely use what you have until it dies, years down the road. We needed a new battery, and after doing a lot of reading, liked the idea of a Lithium battery for the reasons stated above, despite the high cost. We probably wouldn't have gotten a 300 AH unit, except for coming across a nine month old floor model the dealer was willing sell at a good discount.

We liked the idea of having a lot of reserve power at a low weight, and no service requirements. It's pretty big (though smaller and much lighter than equivalent amp hours in other types of batteries), so we had to install it inside under the seat in the front eating area. We wanted the battery inside in any case, because we've read stories of batteries "walking away" on occasion. Also, Lithium batteries perform better if the are kept warm during the winter. Lithium batteries are sealed, so no concerns about off-gassing or ventilation requirements. (Other types of sealed batteries are also available for RV's)

We still need to get a true-sine inverter, so we can safely charge our computers. At some point, though the Zamp comes with a built in, Lithium capable controller, we may still shift over to an MPPT type of charger which is supposed to be more efficient than the less expensive WPM charger that comes with Zamp and other portables. For now, we are going to see how things go with what we already have.

Caveat: I'm a (retired) biologist, actually a shrimp and algae farmer, and do not have a deep understanding about how all of this equipment works, or the technical language involved. There are a lot of folks in this group that really do understand all the ins and outs. Like you, I did a bunch of reading, trying to make what seemed like logical choices (to me). I also spoke with people at Zamp and Relion after reading reviews of their products, to ask as many questions as I could. Some of our choices were kind of expensive, but I'm I'm still a believer in you get what you pay for (I hope; I'm sure I'm rationalizing :>).

We'll be taking another, shorter trip in a couple of weeks, and that will be the first real test of the Zamp portable solar kit with the new battery. We'll try to update on this combination when we return, and also reach a decision about the need for more solar panels when we get back. As one of the other readers suggested, we would plan to continue using the portable kitas a part of the system, and/or as a reserve booster. However, we're still hoping to avoid a roof mount.

Good luck with your search, you're on the right track.

Josh

[TomK]

Originally Posted by John Linck

I chose to roof mount a 100 watt panel for a couple of reasons. First, I thought storing a portable panel while in transit would be problematic as our 13 and Subaru are smallish. I suppose this would be easier if one chose two 50 watt panels in some kinda case. Second, I go Scamping to hike and be outdoors, not fool around chasing the sun with a theft prone solar panel. My roof mount was/is really just Install it and Forget it. It captures the photons nicely and keeps the battery charged. I just watch the voltmeter. I did oversize it by 2X at 100 watts to make up for its non-tiltablilty, occasional tree branches and Winter's low angle sun since we often travel in Feb/Mar to avoid the worst of Wisconsin's Winter.

Also, the panel maintains the battery during the 9-10 months that we are not on the road. The Scamp sits in our driveway and a portable panel would just get in the way on our crowded inner city lot. With my first Scamp I set a time switch to turn on an hour a day to power the trailer's older model converter while in the driveway. It maintained the battery OK, but it boiled out a bit of water and I was always tripping over the drop cord. Plus I worried a bit about the 120 volt warm converter with its fan possibly failing is some manner and cooking my egg.

I am a little perplexed by folks worried about roof loading. I have climbed around on top of my Scamp on several occasions and though I do lay down some padded plywood panels to distribute my 200 pounds I have not noticed any deflection or sagging of the roof. My 17 pound solar panel, supported on 4 widely distributed brackets, seems a negligible addition.

All that said, I encourage everyone to try solar in any configuration. It really helps us stay longer in beautiful places far from the grid, like the picture below. There are lots of workable solutions and one solution isn't best for everyone.

john

Pic of our solar panel collecting photons at Jumbo Rocks Campground at Joshua Tree National Monument.

John, can you easily remove your solar panels for cleaning or waxing? It seems like it might be a leaf and debris collector if not. I like your install it and forget it approach. We are planning an extended boon docking trip in the near future, so I plan to see if we need it, but if we do; I think I'd lean toward a set up like yours.

That picture is amazing. Not just for the beautiful rig, but those boulders look surreal! In fact they look like some paper mache' rocks from an old '50's TV Western show. I can picture Roy Rogers shooting the bad guys from behind them. Always enjoy your posts.

Tom

[C&G in FL]

Not wanting to drill holes in the shell is understandable. But.......there are are already seven holes in the shell, like the vent, the Escape hatch, the door, every window, the power cord, and in the case of a Scamp, every screw supporting aninternal structure, etc. And they do not leak because they are sealed. While tape may be adequate, it also may fail (and has been known to fail) allowing a solar panel to fly off a trailer and possibly crash through the windshield of a trailing vehicle killing one or more of its occupants. I fail to understand why not utilizing a fail-safe method to attach a solar panel securely is trumped by the concept of “I don’t want to put holes in my trailer” even if it may put someone else in harm’s way on a public highway. Bottom line, bolt it down or get a portable panel. At 60 mph, the is a lot of wind load on a panel on top of a trailer. My two cents.

[Borrego Dave]

Originally Posted by TomK

John, can you easily remove your solar panels for cleaning or waxing? It seems like it might be a leaf and debris collector if not. I like your install it and forget it approach.

Good question Tom and I also agree with CPW of bolting it down as sealing it from leaking is pretty much a slam dunk job. So this got me to thinking of Johns and others bolted setups of cleaning under it and the sun angle. The brackets design could easily be made to hinge on the front and a quick disconnect on the rear to allow it to be lifted for underside roof cleaning and maybe a better angle to the sun at times. MMM, I'm going to have to do a bit of drawing...........

[gordon2]

Originally Posted by Borrego Dave

.. So this got me to thinking of Johns and others bolted setups of cleaning under it and the sun angle. The brackets design could easily be made to hinge on the front and a quick disconnect on the rear to allow it to be lifted for underside roof cleaning and maybe a better angle to the sun at times. MMM, I'm going to have to do a bit of drawing...........

I bought these brackets with the idea of putting a panel on the roof of the Scamp but have not used them because I find the portable idea works much better for me. I would be willing to sell the brackets. but it might cost a bit to ship them.

[Radar1]

We started with a portable 90 watt panel on our 16' Scamp, but there were times and places where we didn't want to leave the panel unattended.
We added another 90 watt permanent panel on the roof, and that fulfills our needs most of the time. During colder fall/winter camping trips where the sun is lower and out fewer hours, and we use our propane furnace and a CPAP machine it's nice to have the 2nd panel available for more amps.
We created four 12" long brackets, one for each corner, and attached via VHB tape. We also attached a small bracket using an existing rivet hole, and replaced that rivet with a 1/4 x 20mm screw/nut combination to have at least 1 mechanical backup to the VHB tape.
Your 25 amp daily usage would deplete the battery in about 2 days without solar, so having a solar panel(s) would be a great idea for your usage. A stationary rooftop would not be quite as efficient as a portable unit that can be aimed directly at the sun, but even portable units are placed in an arbitrary non-optimum position unless you stick around the campsite to let the panel follow the sun.
Have fun boondocking!

[John Linck]

Originally Posted by TomK

John, can you easily remove your solar panels for cleaning or waxing? It seems like it might be a leaf and debris collector if not. I like your install it and forget it approach. We are planning an extended boon docking trip in the near future, so I plan to see if we need it, but if we do; I think I'd lean toward a set up like yours.



Tom

Nah, I cannot easily remove my panel. Should have thought of that. I concentrated on not letting it blow off. Also, I don't spend much time cleaning my roof. Rain seems to do most of that work. I haven't noticed any leaves, etc collecting under the solar panel but I expect a blast of water from a hose would take care of them. There is about a 2 inch gap between the panel and the fiberglass. Once or twice a Winter I use a push broom to push snow off the roof if it gets to be a foot or more. The dark color of the solar panel helps keep it snow free.

So far I haven't waxed my trailer either. It lived in a garage for the first two years of its life, now its outside all the time. It still looks pretty great.

john

Pic of a big rock at Arches National Park

[patrick crawford]

i've evolved into a somewhat different solar arrangement. for several years i employed a 60w panel mounted on an adjustable frame. that arrangement worked well, but i tired of packing and unpacking the thing. a few years ago i had to remove ladders from my useable tool list (yeah, i was falling off). so that left the rooftop cargo carrier on the truck available. i mounted the panel on that carrier. it's easily removable (4 large metal hose clamps) if i need it on the ground. i recently added another panel (100w) and mounted it directly to the roof of the truck's cap (screws and 3m tape). so now, with 20' cables, i can put the little house in the shade and park the truck in the sun (in theory). should i want to leave the site for a while and still charge i can put the 60w panel on the ground.

right now i'm on the first trip out with this new solar arrangement. for three weeks i've been in state and forest service campgrounds with 'tricity. and having that hookup has been essential since cloudy and rainy has been dominant. in a few days i'll be urbandocking in a parking lot in baltimore with nada hookups. (the lot is security fenced and locked). so...if momma nature cooperates i'll find out how well all those watts work. if all else fails i do have the trusty honda 2000i living on top of the propane tanks.

oh yeah, one tip...if you're making cables to connect the panels to the trailer i would advise against those the preassembled cables with mc4 connectors. the ones i got from renology are 2 separate very stiff cables. i could have simply purchased a spool of heavy gauge wire and made my own that would have been much more manageable. i'm not really crazy about those mc4 connectors either...

p@

[gordon2]

Originally Posted by patrick crawford

...
oh yeah, one tip...if you're making cables to connect the panels to the trailer i would advise against those the preassembled cables with mc4 connectors. the ones i got from renology are 2 separate very stiff cables. i could have simply purchased a spool of heavy gauge wire and made my own that would have been much more manageable. i'm not really crazy about those mc4 connectors either...

I did that.. made up my own cables with ten gauge wire that I had for ham radio power supply, and MC4 connectors that I put on myself. The wire was not UV rated however, became faded and was on it's way to failure after a too short time. So I went ahead and spent a little more money for cables specially for solar (with UV rated wire). My cables came from WindyNation and the cable is stiffer but its not that bad and still perfectly usable. Perhaps the Renogy (not renology) cables are worse.

What is the objection to the MC4 connectors? They are water tight, easy to put on cable for custom configurations (as long as you get the genders right) and they are the industry standard so you can mix and match components. The only problem I have seen is that sometimes MC4 connectors from different manufactures do not have the same manufacturing tolerances, so they will fit together but sometimes not easily. There are simple and inexpensive tools to facilitate separating them.