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penra
06-10-2019, 07:21 PM
Considering solar add-on in Montana 3120RL. Actually wondering about adding the 265 watt solar package with 2000 watt inverter. Is that adequate for dry camping? Thinking lights, frig, tv and satellite dish?
The 'package' only shows solar panel and inverter, but the brochure states it includes a 30 amp MPPT.
Without storage batteries in addition to the two 12v onboard, how useful is a solar collection system? Has anyone added solar? Want to learn more about it.
**Edit** Without batteries was stated because the offered package from Keystone has no additional batteries. Seems like a flaw.

Fishsizzle
06-10-2019, 10:04 PM
Some pretty smart people on here, search or give it some time.

Search “gone with the Wynns” on google. Kinda fun adventure they had. They explain their struggles with solar to fit their lifestyle . There are many others.

There are good ideas on how to proceed, but most start with figuring out how much you will use each day, and then size your battery bank, then how much it will take to bring it back to full charge each day. I no expert by any means, but charging phones, running TV or computers will start to add up.

For me, I have a Residential fridge, so I’m Trying size a battery bank and enough solar to keep the fridge running. We don’t use much beyond that thing.

Roscommon48
06-11-2019, 05:03 AM
I'd just forget the refrig on solar...use the propane.


as for the rest, i'd be talking to solar companies that specialize in rvs/marine. ie. https://www.renogy.com/products/solar-kits/rv-van/

Fishsizzle
06-11-2019, 05:13 AM
I'd just forget the refrig on solar...use the propane.


as for the rest, i'd be talking to solar companies that specialize in rvs/marine. ie. https://www.renogy.com/products/solar-kits/rv-van/


Definitely google the Wynns then, they went with Renology system off Amazon for their rig.

They went all in with big time inverter and lithium batteries which is overkill unless you have super deep pockets and are full time adventure/off grid, get away from it all.

GeekSquadOfUn
06-11-2019, 05:57 AM
The key to Solar is having good batteries - with good reserve capacity. You've got to store that energy and deploy it when required.

The Wynns have indeed put out some good videos, even though they're now sailing and have dumped RVing ;-)

Fishsizzle
06-11-2019, 06:03 AM
The key to Solar is having good batteries - with good reserve capacity. You've got to store that energy and deploy it when required.

The Wynns have indeed put out some good videos, even though they're now sailing and have dumped RVing ;-)

I know, total adventure hounds. I could never sail.

Good advise. I just upgraded to a (6) 6 volt battery system. 4 for the coach and 2 for the fridge, going to isolate them and maybe pick up a suit case charger for the fridge bank and try it out.


Just noticed they said without batteries, yeah solar is useless without batteries

Canonman
06-11-2019, 11:01 AM
Considering solar add-on in Montana 3120RL. Actually wondering about adding the 265 watt solar package with 2000 watt inverter. Is that adequate for dry camping? Thinking lights, frig, tv and satellite dish?
The 'package' only shows solar panel and inverter, but the brochure states it includes a 30 amp MPPT.
Without storage batteries in addition to the two 12v onboard, how useful is a solar collection system? Has anyone added solar? Want to learn more about it.

A 265w solar package is quite adequate for most RV dry camping. Assuming your fridge is NOT the residential model and will run on propane, using lights, water pump and other 12vdc accessories would be no problem. Judicious TV and satellite use in the evening with an inverter would be no problem as long as you don't "party" all night. What you want to stay away from is using the microwave, toaster, electric fry pan, hairdryer etc. Any 110vac device that creates heat from volts/amps will deplete your batteries rather quickly.
Assuming your existing batteries are group 24 RV Deep Cycle, you have about 80 amp hours of storage each or roughly 160 A/H.
I'm guessing your 265w solar panels will generate about 250 w at 14 or so amps under ideal conditions. That's close to 18vdc which is plenty to recharge your batteries. Rule of thumb is 3% of your total amp hour storage capacity is needed to fully charge your batteries so you have plenty of head room there. No problem if you wanted to add more batteries down the road.
We have a 200w system and find it completely useful. We almost never run the generator (usually only if we need A/C or the DW wants to dry her hair) and enjoy the peace and quiet we expect when dry camping.

penra
06-11-2019, 05:33 PM
A 265w solar package is quite adequate for most RV dry camping. Assuming your fridge is NOT the residential model and will run on propane, using lights, water pump and other 12vdc accessories would be no problem. Judicious TV and satellite use in the evening with an inverter would be no problem as long as you don't "party" all night. What you want to stay away from is using the microwave, toaster, electric fry pan, hairdryer etc. Any 110vac device that creates heat from volts/amps will deplete your batteries rather quickly.
Assuming your existing batteries are group 24 RV Deep Cycle, you have about 80 amp hours of storage each or roughly 160 A/H.
I'm guessing your 265w solar panels will generate about 250 w at 14 or so amps under ideal conditions. That's close to 18vdc which is plenty to recharge your batteries. Rule of thumb is 3% of your total amp hour storage capacity is needed to fully charge your batteries so you have plenty of head room there. No problem if you wanted to add more batteries down the road.
We have a 200w system and find it completely useful. We almost never run the generator (usually only if we need A/C or the DW wants to dry her hair) and enjoy the peace and quiet we expect when dry camping.

Exactly what I wanted to know! Thanks.

Stircrazy
06-13-2019, 06:37 AM
just to add, I would add more panels if you can. the price of solar panels are very cheep now. I have 480 watts (3, 160 watt panels) through a 30 amp mpt controller I did have 320 and when I added another it did make a big difference. if you could double that wattage and get up around 600 with a 3000 watt inverter and auto change over switch you will be laughing. the extra wattage will just let you get more charge on cloudy and spring/fall season when the solar isnt as strong.

Steve

Hodgy
06-13-2019, 09:53 AM
the extra wattage will just let you get more charge on cloudy and spring/fall season when the solar isnt as strong.
Steve

I had 100 watt SP and one 12 volt DC battery last year and did OK dry camping for 4 days last August.

This year I added another 100 watt SP and went to two 6 volt GC batteries. You are right, I am getting good solar on cloudy days, 13.8 volts.


.

Stircrazy
06-13-2019, 03:50 PM
I had 100 watt SP and one 12 volt DC battery last year and did OK dry camping for 4 days last August.

This year I added another 100 watt SP and went to two 6 volt GC batteries. You are right, I am getting good solar on cloudy days, 13.8 volts.


.

ya, I was in Alberta for my grandfathers funeral in mid sept, had the furnace running all day, and all the luxuries of being plugged in. I left the day I picked up the 5th and I didn't know there was an issue that the shore power wasn't working to charge the batteries ( 4, 235amp 6V ) as every night before bed I would check them and they were full. then I noticed one morning they were down to about 60%. my panels were topping them off so they were full every night and apparently I was running everything off my inverter. at that time I only had 320 watts of panels as they didn't get the 3rd installed before I had to leave, now with 480 watts I don't worry about if I have power or not unless its hot as heck and we need the ac for the dog. needless to say I am now a full believer in solar on a RV.

Steve

penra
06-13-2019, 07:54 PM
I had 100 watt SP and one 12 volt DC battery last year and did OK dry camping for 4 days last August.

This year I added another 100 watt SP and went to two 6 volt GC batteries. You are right, I am getting good solar on cloudy days, 13.8 volts.


.

Are the two 6V batteries in addition to or instead of your 12V RV batteries? And can anyone explain why 6V batteries are better for storing SP than 12V?

Scott902
06-14-2019, 01:36 AM
Are the two 6V batteries in addition to or instead of your 12V RV batteries? And can anyone explain why 6V batteries are better for storing SP than 12V?

the GC 6V batteries have a lot more reserve power/amp hours

JRTJH
06-14-2019, 04:26 AM
Golf cart batteries have thicker lead plates that sit higher off the bottom of the battery cavity. That provides for increased charge/discharge cycles than "deep cycle marine/RV" batteries. As any battery charges, it gives off bubbles of gas, along with those bubbles, a small chip of lead is converted to "hydrogen sulfide", a solid that settles to the bottom of the battery. After many charge/discharge cycles, the plates are too thin to function properly and the amount of hydrogen sulfide in the bottom starts to "short the lead plates" making them unable to accept electrons as easily.

The thick plates in the golf cart battery can stand the charge/discharge cycles better than the marine/RV batteries which have thinner plates and less space under them for "trash" to accumulate.

Just as a "light weight" hybrid car with a 1.1L gas engine can save on fuel and get you back and forth to work, it's not "the best choice" for heavy duty use or for towing a trailer. It may accomplish most tasks for a while, but the design and capability just aren't up to prolonged heavy duty use. It's the same with batteries. Those designed for slow release of electrons and multiple charge/discharge cycles will last longer (rhick lead plates mean reliability with extended use) than those that have more plates that are thinner (to provide both slow release AND high amperage use to start a motor).

bbells
06-20-2019, 08:52 AM
Get the smallest inverter you can get away with. Don't even think about using solar battery power for the refrigerator or AC. My led lights are 2.5 watts each. My TV is 40 watts. I don't know about the dish, but I would figure about the same as the TV. If your panels are aimed right on a sunny day you will get a maximum of about 1250 watt hours of power into your battery. To be safe, you should plan on only using 1/3 of that since it is not always sunny. Let's say 450wh. That means your batteries need to be at least 900 watts (or 75 ah). You could use your TV with dish for about 4 hours if you use minimum lights and other power. IMHO, you should get a second panel or a generator to back up the system for cloudy days - Or for expended tv viewing. That would double the time you can watch - As long as your batteries are at least 150ah, which if they are real deep cycle batteries and not fake marine deep cycle batteries, they should be a minimum of 100ah each.

SR71 Jet Mech
06-20-2019, 01:36 PM
Bottom line is how much power will you consume? 6v GC2 batteries far excede the 12v , unless of course you switch to lithium ion’s. John explains it perfectly.
For very minimal weekend boondocking you should be fine (unless you have deep cycle/marine batteries. If it cloudy however, you probably will have problems. Even a propane fridge uses some wattage for cooling.
Another good source is RVwithtito.com. Like the Wynn’s he has a lot of videos explaining the how’s and whys. Very informative.
Just do lots of research before jumping in.
It will save you headaches in the long run.

Scott

SR71 Jet Mech
06-20-2019, 01:45 PM
It can be super simple or somewhat extreme....mine got carried away but, I do have a residential fridge.

DonnieBlitz
06-21-2019, 03:36 AM
Go here and read. It will answer all your questions. https://handybobsolar.wordpress.com/

roadglide
06-21-2019, 03:56 AM
Considering solar add-on in Montana 3120RL. Actually wondering about adding the 265 watt solar package with 2000 watt inverter. Is that adequate for dry camping? Thinking lights, frig, tv and satellite dish?
The 'package' only shows solar panel and inverter, but the brochure states it includes a 30 amp MPPT.
Without storage batteries in addition to the two 12v onboard, how useful is a solar collection system? Has anyone added solar? Want to learn more about it.
**Edit** Without batteries was stated because the offered package from Keystone has no additional batteries. Seems like a flaw. 2000 W Pure sine wave is a good starting point with one more panel and three nice 12 V AGM batteries. There’s so much information out there on Internet. But it’s worth it to install something you can really use when dry camping.