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InterBlog · 01-07-2016, 02:12 PM

FWIW, we settled on a system with 300 watts (3 x 100 watt Grape Solar monocrystalline panels of the type Lewster references) to start with and may add a fourth later depending on the results we see. You can "calculate" your needs but realize that there will be many variables affecting the system, some of which are uncontrollable (like weather and tree canopy at your destinations) and some of which may remain unknown (like parasitic draws). In the research we did, nobody seemed to complain about having over-designed their systems. In fact they needed to, in order to get where they wanted to be.

The general guidelines are: Listen to Lew, listen to Handy Bob (he has a blog), and over-design.

We are not yet finished with our installation but if you are interested, you can read more in these first two descriptive blog posts, although some of our physical installation challenges will not apply to a trailer:

THE INTERSTATE BLOG: SOLAR PANEL INSTALLATION, PART 1: PREAMBLE
THE INTERSTATE BLOG: SOLAR PANEL INSTALLATION, PART 2: EXTERIOR COMPONENTS

KJRitchie · 01-07-2016, 03:01 PM

Once you get into wanting to run stuff off an inverter then things get more complicated and costly; more battery capacity, more solar capacity, more installation issues, inverter equipment to purchase. I'm thinking for some items I need to run occasionally that require AC I'll just get a 2000w generator to run for the few minutes the wife needs to use a hair dryer or the microwave when boondocking in the middle of no where.

Kelvin

Gearheart · 01-07-2016, 03:14 PM

I bought a post ice storm generator, 3500 watt, for $250 Canadian. That's about $180 US. It had less than 15 hours on it. By comparison a 40W solar panel is around $200 CDN. I didn't need to think long nor hard to figure it out.

interstateflyer · 01-07-2016, 04:46 PM

We have happier camping neighbors now that we've gone solar.

lewster · 01-07-2016, 05:01 PM

"You will never be able to really run AC off of any conceivable installation of panels and batteries on your trailer, or other high draw devices. From experience the best bet is a portable 140-160 watt solar panel that you can move a couple of times a day to get it in the sun and a couple of good house batteries. You start out fully charged, you use up 30-40 amps a day, you get an "average" of 30 solar amps a day, you run an "average" deficit of 5- amps per day for a week of boon docking. You'll be OK." ……….Clipper2014

NEVER say never!!!!

I'm sure that the 20 or so folks that have large lithium battery packs with 3000 watt Magnum hybrid inverters that I have recently installed would be VERY INTERESTED in your 'experiences'. They seem to have NO PROBLEMS running a roof A/C unit from 2.5-5 hours simply from the battery alone. They also have no problems running that same roof A/C ALL DAY if they add a single 2000 watt generator into the mix.

Will that put a pretty large dent in the battery's capacity…..sure. Will their ample solar charging systems replenish that capacity in very short order….you bet! Can a single Honda or Yamaha 2000 watt almost silent generator bring those same batteries up to full charge (although it's not really necessary with lithium batteries) in a matter of a few hours if necessary at a charge rate of 125 amps per hour thru their Magnum inverter/charger….. ABSOLUTELY !!

Please do a little research before making statements that have no basis in fact!!!

BoldAdventure · 01-07-2016, 05:22 PM

I'd be SOL up a creek if I just had a "140-160 watt portable panel" - everyone's power consumption needs are different.

+1 what Lew said about the A/C. Totally possible.

KJRitchie · 01-07-2016, 05:48 PM

All it takes is money.

Molinari47 · 01-07-2016, 06:35 PM

I've been looking to install maximum solar capacity on my AS as well so I have followed the postings with interest. Go Power's top of the line kit (hard not flexible panels) has total wattage of 480 watts ( 160 watt panels) which is capable of generating 27 amps per hour depending on sun exposure. Eventually, however no matter how much juice you can generate from solar it doesn't matter if you don't have the capacity to store it. New AS (25 foot and above) come equipped with two group 27 Lifeline batteries which have an amp capacity of 100 each (200 when wired in parallel). I have been thinking of switching to 6 volts but two six volts wired in series (to make 12 volts) don't double the amps. I also have considered adding
4 6 volts wired in series/parallel which I think would give me about 800 amps. Couple of questions to the group:

1. Is is possible to wire two 6 volts in series parallel?

2. Has anyone had any experience in modifying the AS battery box to accommodate 4 6 volts,

3. AS wiring from panels to controller and from battery box to solar controller is I believe 10 gauge. I'm thinking of replacing with 6 or even 4 gauge.

Thanks in advance for any assistance.

dznf0g · 01-07-2016, 06:38 PM

Quote:

Originally Posted by Clipper2014

You will never be able to really run AC off of any conceivable installation of panels and batteries on your trailer, or other high draw devices. From experience the best bet is a portable 140-160 watt solar panel that you can move a couple of times a day to get it in the sun and a couple of good house batteries. You start out fully charged, you use up 30-40 amps a day, you get an "average" of 30 solar amps a day, you run an "average" deficit of 5- amps per day for a week of boon docking. You'll be OK.

The above arrangement will cost you less than $500, and the work to move the panels around. $500 might be less than what it would cost you just for labor to mount panels and install a solar charging system in your trailer.

On really sunny days when you can keep your panels exposed to the direct sun for 6 plus hours a day, you will run a surplus, on crummy days a deficit. Rather than running the furnace all the time, wear a sweater. Read or play games rather than watching TV. You'll be OK.

If you want to go really crazy you could get a second panel of the same size, about $350, assuming the charge controller you bought for the first panel can handle the load. You wire them together, but now it's a more time consuming or a two man job to move and store them. They only weigh about 25 pounds, but with all the wiring it is more complicated. With this extra panel you will now pick up a lot more amps. Use the micro wave with an inverter a little to reheat your coffee or maybe even prepare your TV dinners. Use your hair dryer for a few minutes. Fat City!

More direct and productive of a lot more amps is a generator. One small, quiet, economical Honda generator will easily keep your battery's topped up if you limit your amp draw. You would probably need to run it 1-2 hr.s per day. The solar panels don't need to be run, just moved to produce quiet power See how your neighbors like it?
A couple of big, snarling Honda generators can be run together with your AC, the noise of each canceling out the noise of the other and viola! AC.
These kinds of generators, however, have a weigh penalty (80b.s each) for you to manage and store, and require you maintain a good supply of gas on hand to feed them.

Cheers

Bingo, that's where I am.

BoldAdventure · 01-07-2016, 07:28 PM

Quote:

Originally Posted by Molinari47

I've been looking to install maximum solar capacity on my AS as well so I have followed the postings with interest. Go Power's top of the line kit (hard not flexible panels) has total wattage of 480 watts ( 160 watt panels) which is capable of generating 27 amps per hour depending on sun exposure. Eventually, however no matter how much juice you can generate from solar it doesn't matter if you don't have the capacity to store it. New AS (25 foot and above) come equipped with two group 27 Lifeline batteries which have an amp capacity of 100 each (200 when wired in parallel). I have been thinking of switching to 6 volts but two six volts wired in series (to make 12 volts) don't double the amps. I also have considered adding
4 6 volts wired in series/parallel which I think would give me about 800 amps. Couple of questions to the group:

1. Is is possible to wire two 6 volts in series parallel?

2. Has anyone had any experience in modifying the AS battery box to accommodate 4 6 volts,

3. AS wiring from panels to controller and from battery box to solar controller is I believe 10 gauge. I'm thinking of replacing with 6 or even 4 gauge.

Thanks in advance for any assistance.

What kind of batteries do you think you are using that will give you 800Ah?

Yes you can wire 6V batteries in series parallel like so. However, to clarify a point. When you wire the two 6V batteries in series you double the voltage, not the Ah.

When you take four and wire them in series parallel you double the voltage and the Ah.

So if you have two 6V batteries that equal 100Ah and you wire them together in series you end up with 12v and 100Ah. If you wire 4 in series parallel you end up with 12V and 200Ah.

Hope that makes sense to you.

Also you can only use safely 50% of that power. So if you have four 6V batteries at 400Ah you can safely discharge 50% so 200 usable Ah.

If you have Airstream's solar package, increasing the wiring won't do much. It's a garbage system. And I don't say that lightly. Fine for little group 27's but not for real systems.

davidz71 · 01-07-2016, 09:39 PM

I purchased two 100 watt solar panels from AM Solar along with one of their controllers. I later added a 65 watt panel for a total of 265 watts of power. I have been able to run two Fantastic Vent fans on medium 24 hours per day on a single Trojan 12 volt 115 amp hr. battery. Running the furnace during winter camping while boondocking hasn't presented a problem either. Several years ago I added a Jensen 12 volt TV and recently decided to replace the single Trojan with two identical 115 amp hr. 12 volt Trojan batteries on the tongue of the trailer so that I could check battery water much easier. This combination has been a dream for all kinds of weather. I highly recommend AM Solar. They are nice people, put out great products and their kits come with all the instructions needed to install them yourself. I've had my system for over 8 years and am perfectly happy with it.

switz · 01-08-2016, 02:06 PM

Our Classic's initial 600 amp-hour four Lifeline (model 6ct 6Vdc at 300 amp-hour) batteries were able to start and run the 15,000 BTU air conditioner through the Magnum MS-2812 inverter/charger with no generators attached. We replaced the four Lifelines at 92 pounds each with one lithium iron phosphate 600 amp hour battery at 168 pounds and its will start and run the air conditioner as well with no generator.

We have a 300 amp-hour lithium iron phosphate battery in the 23D and with the Magnum MSH-3012 hybrid inverter/charger we have the ability to draw power from the battery as needed and can start and run the 13,500 BTU air conditioner with a single 2,000 watt Honda generator running.

Molinari47 · 01-09-2016, 06:27 PM

Thanks Mike for the information. I was thinking of 4 6 volt batteries with 210 AMHs each wired in series parallel. I know that all of the maximum amp hours have to be reduced by 50% so even with 800 amp hours, my max would be about 400 (depending on temps). My big issue now is storage of the batteries as 4 6 volts take up twice the space (with about twice the weight) of the two standard Group 27s that will come with the unit. AS has already shot down my request to fabricate something at the factory as I have been told they are too busy (isn't customer service wonderful). Still waiting to hear whether they will upgrade my wiring.

Molinari47 · 01-09-2016, 06:34 PM

Switz: where did you place the 4 6 volt life line batteries. I thought of lithium but decided not to use lithium as I do a fair amount of cold weather camping (20 degrees and colder). Thanks for the help.

BoldAdventure · 01-09-2016, 06:57 PM

Quote:

Originally Posted by Molinari47

Thanks Mike for the information. I was thinking of 4 6 volt batteries with 210 AMHs each wired in series parallel. I know that all of the maximum amp hours have to be reduced by 50% so even with 800 amp hours, my max would be about 400 (depending on temps). My big issue now is storage of the batteries as 4 6 volts take up twice the space (with about twice the weight) of the two standard Group 27s that will come with the unit. AS has already shot down my request to fabricate something at the factory as I have been told they are too busy (isn't customer service wonderful). Still waiting to hear whether they will upgrade my wiring.

Since you want a big bank, and were willing to pay for fabrication, I would seriously consider lithiums. The advantages are worth the cost. Smaller footprint, less weight, greater depletion rates 80~90%, faster recharge rates (takes bulk charge to 99%), longer life, totally maintenance free.

My 400Ah bank provides me with 380Ah usable weights only 110lbs and takes up no more space than two and half group 27's.

This would make sense considering your smaller Airstream. I would seriously consider the pro's more than just looking at the cost.

Quote:

Originally Posted by Molinari47

Switz: where did you place the 4 6 volt life line batteries. I thought of lithium but decided not to use lithium as I do a fair amount of cold weather camping (20 degrees and colder). Thanks for the help.

You can place them inside where that won't be a problem, FYI. It's been dropping down to 38 where I am and most of my cells are staying at 74 degrees even with the thermostat set to 60.

What becomes a problem, is sticking them outside in 20-degree weather and trying to charge them. But you can actually deplete them safely in -20 degrees. (Speaking for Elite GBS cells).

Again, might want to re-examine in light of new information.

alano · 01-09-2016, 07:29 PM

Quote:

Originally Posted by Molinari47

3. AS wiring from panels to controller and from battery box to solar controller is I believe 10 gauge. I'm thinking of replacing with 6 or even 4 gauge.

Thanks in advance for any assistance.

Run larger wires if you want but it's possible to install 400 W of solar in a series/parallel arrangement using the existing solar pre-wiring and keep the voltage losses to less than 2%. I did this on my 30' Classic and I'm very pleased with the results. I was also able to reuse the existing CAT 5 for the solar controller's remote/battery monitor.

Molinari47 · 01-10-2016, 07:27 AM

Thanks guys for the response. Has anyone had success in having the wiring upgraded at factory. I asked AS and was told that they are not capable of doing. Thanks again for the advice.

switz · 01-10-2016, 07:36 AM

We made a custom stainless steel enclosure for the four Lifeline model 6ct batteries that weighed 94 pounds each and mounted the enclosure behind the ProPride jacks against the front skin of the trailer. Our tongue weight on the 2014 Classic was 1,375 pounds after all the modification work was completed.

Getting to the old battery box where the disc brake pump and controller is located required removal of the jacks and propane tanks. A small access door allowed top po
I got up the brake fluid without removing those two parts.

Replacing the Lifelines with one lithium iron phosphate 168 pound battery mounted inside under the front sofa reduced the tongue weight to 1,750 pounds.

dznf0g · 01-10-2016, 08:03 AM

Fat fingers, Switz?

rodsterinfl · 01-10-2016, 08:25 AM

Like Alano I used the prewire though my power needs and setup are different. I have 150 watts on top, a solar suitcase 100w and a 50w flex panel. I have quick-connect plug ins on the battery box for both the suitcase and 50w. I use the suitcase when camping as an adjustable out of the canopy supplement to the roof unit and plug in the 50w as a secondary supplement. When in storage, the 50w is plugged in to keep the batts up. This 300 watt system, is based on keeping my meager needs on the existing battery complement and it works well.