Portable Solar Panels

[migriffin]

Hi All,

I finally bit the bullet and ordered a 2014.5 Airstream Interstate after pining over one for over a year. I'm planning on doing a lot of camping off the grid and was thinking of purchasing some portable solar panels to help keep the electricity flowing. I'm visiting one park in Big Bend that won't allow generator use so I thought solar panels would be a good alternative.

I was considering Goal Zero panel setup as seen here: Advanced Emergency Preparedness - Goal Zero’s RV & Trailer 12v Battery Rechargers - Advanced Emergency Preparedness

OR a Zamp Portable setup as shown here:
Portable Solar Systems | Zamp Solar

Has anybody tried this or have thoughts on how it'll work? Where exactly would I connect the panels? I'm not sure where the coach battery is located or how accessible it is. Do you have any thoughts on the above manufacturers or alternatives?

Thanks for your feedback. I can't wait to get on the road.

Michael

[Boxster1971]

I don't have experience with larger portable panels. I did have a small Goal Zero panel to charge my cell phone. It was useless and I returned for a full refund.

[carl2591]

AM solar panels are good quality it appears. do more reading and reaschurse on panels. I was think about this myself for the future.

I would think, if you have room to go big watts as possible. instead of 3 100 watt deals on 325 watter at 24 volts would be a better deal. not sure the plus vs minuses of one large vs 3 smaller.

just something to think about.

[toskeysam]

The Advanced Emergency Prep. system cannot be used with your AGM batteries, from what I just read about their system.

[toskeysam]

I would be curious to know if the Zamp system, or any portable system, could be connected to the Interstate system that already has a solar system of it's own......or would this confuse the existing on board controller.

[Argosy 7728]

The Zamp chargers have a sidewall accessory that hooks to the battery and mounts to the side of the trailer and you just plug the panels into it.

[TinShack]

Another option is this one although I like the Zamp controller better...http://gpelectric.com/files/gpelectr...PSK-80-120.pdf

[mefly2]

We have the Goal Zero "briefcase" panels that unfold (excellent design and construction - relatively low output unless direct sun). GZ also makes some other great products as well (batts).

Zamp folding panels 60 watt (poor quality of the wiring harness; charge controller died; questionable customer service ... but the solar panels themselves are excellent).

[scamp]

What would you like to power ? and for how long because most small folding panels are low wattage less then 100 watts they would extend the time on use of your batteries and I'm not sure if you have agm batteries or flooded acid deep cycle, and you should not discharge your batteries more then 50% or there life gets shortened, also agm batteries have a different charge voltage ,some charge controllers can be used on different types of batteries you can adjust the settings I think the midnite solar (the kid ) charge controller is adjustable .most rv and marine batteries are not deep cycle batteries,even if they say ,kinda of a guide if they state cold cranking amps there not true deep cycle batteries,just a guide I use a small 60 watt panel in a off grid cabin and it powers 2 low wattage cfl light bulbs ,small 14" TV ,cell phone,laptop for the evening 4 hours or so and I have 2 deep cycle batteries but if you get a cloudy day I run out of power,I have added a 130 watt (sunforce) panel and this has fixed my running out of power on cloudy days situation,and this panel I have transported it in the back seat of my full size extended cab pickup truck.

[Protagonist]

Airstream Interstates aren't exactly the ideal boondocking vehicles. But with portable panels, it can be done.

If you're going to be in the Big Bend area, then you should have plenty of daylight to work with.

First step, as I see it, is to figure out your 24-hour electrical usage. Leaving out your air conditioner and microwave/convection oven, of course, because they won't run off the inverter anyway. Side note, get some Prodex to cover all of your windows (even the tinted ones) and windshield during the day, because without that, you'll bake in the Big Bend area. Those big windows are like a greenhouse!

Once you have your 24-hour electrical usage, multiply that by 3. That is about how much solar capacity you'll need to keep your batteries charged on a day-to-day basis from solar alone. Multiplying by 3 rather than 2 accounts for the fact that even though you might have 12 hours or more of daylight, unless you want to be constantly re-aiming your solar panels, you'll have time when you're not using them to full efficiency.

In my opinion, your best bet for wiring in portable panels is:
1 - Do not use the charge controller for your rooftop solar. Use a separate controller for your portable panels.
2 - Open up the battery box and make separate connections from the portable controller to the batteries. Use a two-pin plug outside of the battery box so that you can simply plug in the portable solar when you have it hooked up and can unplug when you're not.
2A - Alternately, you already have a 12v power outlet on the right rear quarter panel of the Interstate. You might repurpose that to plug in your portable solar, if you're not planning to plug any 12v appliances into that outlet while camping. I'm not an expert on that, though, so you'll have to work out the details for yourself if you want to try it. I don't know if you could safely back-feed 12v power through the outlet or if you'd have to rewire the outlet to turn it into an inlet.
3 - Get a cargo box that fits the hitch receiver to carry your panels. That way, you don't need folding panels and can get bigger and/or better ones.

The statements above are my opinions alone and do not necessarily reflect the opinions of management.

[wncrasher]

I use a 120 watt folding panel from GoPower! that puts out around 8 amps on a sunny day.

It has an onboard controller and comes with a couple sets of pigtails with anderson style connectors and around 15 feet of cable (one set has ring ends, the other alligator clips) Also comes with a nice soft case for travelling.

I connected one of these pigtail sets directly to the battery bank, spanning my two batteries.

The nice thing about a portable setup is you can park your RV in the shade and put your panels out in a sunny spot.

For guys with trailers, there is a pigtail set available that uses your 7-pin connector on your trailer. It feeds the 12v system thru the charging channel - setup doesn't get any easier than that.

[scamp]

I like the idea of feeding power through the trailer 7way plug ,guess I'm going to make one ! Thanks great Idea!

[Protagonist]

Originally Posted by scamp

I like the idea of feeding power through the trailer 7way plug ,guess I'm going to make one ! Thanks great Idea!

Doesn't help migriffin with his Interstate's solar, but it IS clever! I think it deserves a round of applause.

[wncrasher]

It works up to a certain point. With these portable panels, and their relatively low amperage, it will work with this size wiring. Start daisy chaining panels together, and you'd need to upgrade the wiring.

[gmillerok1]

I bought a 80 watt folding solar panel off eBay (search "folding solar panel") for about half of what it costs from the source you listed.

The solar controller is rated high enough to be able to handle the additional amperage of these panels, so I tied into the same line as the roof panels and ran a low voltage two way plug to the rear bumper. I simply plug them in for additional power when I need it while boon-docking. Works great.

I probably will eventually upgrade to a better controller some day, though.

Gerald

Originally Posted by migriffin

Hi All,

I finally bit the bullet and ordered a 2014.5 Airstream Interstate after pining over one for over a year. I'm planning on doing a lot of camping off the grid and was thinking of purchasing some portable solar panels to help keep the electricity flowing. I'm visiting one park in Big Bend that won't allow generator use so I thought solar panels would be a good alternative.

I was considering Goal Zero panel setup as seen here: Advanced Emergency Preparedness - Goal Zero’s RV & Trailer 12v Battery Rechargers - Advanced Emergency Preparedness

OR a Zamp Portable setup as shown here:
Portable Solar Systems | Zamp Solar

Has anybody tried this or have thoughts on how it'll work? Where exactly would I connect the panels? I'm not sure where the coach battery is located or how accessible it is. Do you have any thoughts on the above manufacturers or alternatives?

Thanks for your feedback. I can't wait to get on the road.

Michael

[migriffin]

Thank you all. It does seem like it's possible to do. It looks like I need to do some more research into the types of batteries used in the coach. Does anyone know if they are AGM? The GoSolar and Zamp system both have their own controllers and it seems like putting a quick connect is pretty simple to do.

[73shark]

Based upon what I was told that mine were AGM and what others have said on this forum, yours are probably AGM.

[wncrasher]

Many controllers on the panels have adjustable settings for battery type. So you should be OK no matter what kind of batteries you have.

[Protagonist]

Originally Posted by migriffin

Thank you all. It does seem like it's possible to do. It looks like I need to do some more research into the types of batteries used in the coach. Does anyone know if they are AGM? The GoSolar and Zamp system both have their own controllers and it seems like putting a quick connect is pretty simple to do.

Since you're talking (writing) about a 2014.5 Airstream Interstate, the coach batteries are definitely two Group 24 AGMs. Depending on the brand, about 85 amp-hours each, plus or minus a few. Factory rooftop solar panel is a dinky 50w panel, good enough to keep the batteries topped up while in storage, virtually worthless for boondocking.

[toskeysam]

Protagonist...you have peaked my curiosity about using the external 12v outlet as a possible connect point for a portable solar array controller output. Logically, it seems like it would work without polarity modification, depending upon the current rating of that outlet/inlet. Any 12v electrical folks out there that could answer this one? It sure would be easier than drilling another hole in my battery box for the feed lead.