Tips for solar charging

Petef729 · 06-10-2020, 02:03 AM

We are taking our greywolf on its first dry camping trip. It still has the 1 small battery they put on it at the time of sale. This weekend I am going to get 2 new batteries for it and a solar powered charger to keep up with the fridge and small draws it will have. Lights , water pump ext.

We are headed to bodega bay on the California coast so sun shine might be spotty. I have a 3500 watt generator for appliance's so I'm not really stressing about that.

Any one have any tips on what to get? 2 6volts strung to 12vdc? 2 group 31. 12 volt rv batteries? How about a charger some one uses on here?

Thank you for the help

**bikendan** · 06-10-2020, 02:12 AM

Go with the two 6v golf cart batteries. There are very few "True" 12v deep cycle batteries made, Trojan being one.
Nearly all the other 12v RV batteries are dual purpose marine batteries that are not true deep cycle batteries.
If youve got money to burn, AGM or Lithium batteries are even better choices.
By the way, I grew up in Sonoma County and spent a lot of time in Bodega Bay.

NJKris · 06-10-2020, 07:03 AM

Very happy with the 2 6v golf cart batts I got from Lowes. Deka brand. As far as solar panels, use search window, there are already a million threads/reviews/comments on this topic.

Petef729 · 06-10-2020, 08:48 AM

Awesome. Thank you for the help. Hopefully my lowes wont have an hour long wait to get in.

UT_Grandpa · 06-10-2020, 12:26 PM

Batteries off the shelf are not charged. You will need to charge them and if you use your trailer converter, you might need 24 hours or so for a full charge (bulk, boost, float). So plan on some time hooked to an outlet/generator.

In my trailer that uses 2 group 24 batteries I can recharge from a night of lights and furnace in about 5-6 hours using 200 Watts of solar. If you go too small on solar, then you are on an unrecoverable downward spiral while boondocking. You will never recharge them fully and eventually they might be down to a very small remaining capacity.

babock · 06-10-2020, 12:33 PM

Actually, batteries off the shelf are charged at the factory. If they weren't they would already be heavily sulfated and you wouldn't want to buy them in the first place. That's why you want to buy fresh batteries if you can as close to the manufacturing date as possible.

TitanMike · 06-10-2020, 01:03 PM

Quote:

Originally Posted by babock

Actually, batteries off the shelf are charged at the factory. If they weren't they would already be heavily sulfated and you wouldn't want to buy them in the first place. That's why you want to buy fresh batteries if you can as close to the manufacturing date as possible.

Not only that but some retailers actually put batteries from stock on "Maintainers" according to the date codes on the battery.

O'Reilly autoparts is one of those. Batteries that have been "on the shelf" are pulled and put on a maintainer that is capable of handling a half dozen batteries at a time and returned to the shelf with a new code and a full charge.

Most batteries have stock rotated frequently so the chance of getting a bad battery has been greatly reduced from days of old.

Where one MIGHT get an old battery that has self discharged considerably is from a small auto repair shop that has a stock of batteries that haven't been rotated. Interstate is one that is commonly found in small shops. Interstate maintains service centers around the country in larger metro areas and will often deliver to a dealer "in demand".

Also gone are the days of "Dry Charged Batteries" that had to be activated when sold. Handling Sulfuric Acid is too big a hazard to employees and they often required some charging even though touted as "ready to go when activated".

robo44 · 06-10-2020, 01:11 PM

We frequent Bodega & Dorian few times a year driving up from SJ since you plan to head out this weekend, lithium may be difficult and pricey to get. When we had out trailer made sure to get sealed AGM Marine Battery (Deep Cycle) no messing with water and you can mount them inside the trailer if needed. (no vent issues)

Comanchecreek · 06-10-2020, 02:06 PM

Best place I've found for Interstates is Costco. They sell tons of batteries, and have a fast turnover so you get fresh batteries. Plus if there's a problem they won't argue with you.

Tom48 · 06-10-2020, 05:14 PM

Quote:

Originally Posted by Comanchecreek

Best place I've found for Interstates is Costco. They sell tons of batteries, and have a fast turnover so you get fresh batteries. Plus if there's a problem they won't argue with you.

Ditto on the best price but be aware that Interstate has three or four grades or Amperage values on their 6v and costco handles the lighter ones. I have gotten 208 am and I think 215 amp there but still $ for $ hard to beat.

On Solar I am a fan of WindyNation.com out in Ventura Calif. He ships a great little 200 watt system that meet most camper's need in sunny weather. Upgrade to his "good" 30 amp pwm charger and upgrade the hook up wires to 10 GA and it is hard to beat. All I need when we install one of his 200 watt systems is fusing and sometimes some extra 8 or 10 ga for the run from charger to Batteries. Or you can get his stuff on Amazon as kits or piece by piece. Or other brands. One of the top evaluators on YouTube DIY SOLAR with Will Prowse, liked the Rich Solar panels from Amazon as best deal for the quality at the time. I say the kit From WindyNation.com (he does free UPS delivery) and save the mounting stuff until you are ready. Meantime you can rig the two panels with hinges and legs and move them around until you become convinced of what a great asset it can be and mount them.

That said, this time I went much bigger (600 watts now and room for 400 more later if I ever need it) and used Renogy panels because they had a 100 watt that was 5 inches narrower than the WindyNation and I had a space issue.

Good luck. no going wrong with 6vs and you will love solar, any solar any way you set it up.

NJKris · 06-10-2020, 08:34 PM

The Lowes batteries were not on the shelf, I had to order them online.

mnoland30 · 06-11-2020, 06:08 AM

I upgraded to two 6 volt batteries (wired in series) from Costco. They were about $90 each, and are real deep cycle. They work much better than the marine batteries I had before. We don't run the heater at night. We use sleeping bags if it is cold. It wakes me up if it come on at night, and I can't go back to sleep. We usually only run our batteries down to about 90%% charge overnight. They last much longer if you don't go below 50%. I have a 100 watt flexible panel on the roof, which has discolored plastic on it, so it isn't as good as when it was new. It is still usually enough in the summer. I also carry another 100 watt panel behind the couch. If it is cloudy, I'll aim it at whatever sun we get that day. I don't carry a generator anymore. In storage, I cover the RV, so I use the battery disconnect, and leave a 20 watt panel facing the sun (very secure storage).

It is important to size your wires from your panel to your charge controller and battery large enough so that you still have over 14.2 volts. There are numerous wire sizing guides on the internet.

My charge controller is the high end one from Bogart Engineering, with the monitor that tells me exactly what is going on in my batteries. It is nice, but probably overkill. Make sure you connect the controller to the batteries first, or it will burn out the LED on most charge controllers.

Comanchecreek · 06-11-2020, 07:21 AM

Quote:

Originally Posted by Tom48

Ditto on the best price but be aware that Interstate has three or four grades or Amperage values on their 6v and costco handles the lighter ones. I have gotten 208 am and I think 215 amp there but still $ for $ hard to beat.

On Solar I am a fan of WindyNation.com out in Ventura Calif. He ships a great little 200 watt system that meet most camper's need in sunny weather. Upgrade to his "good" 30 amp pwm charger and upgrade the hook up wires to 10 GA and it is hard to beat. All I need when we install one of his 200 watt systems is fusing and sometimes some extra 8 or 10 ga for the run from charger to Batteries. Or you can get his stuff on Amazon as kits or piece by piece. Or other brands. One of the top evaluators on YouTube DIY SOLAR with Will Prowse, liked the Rich Solar panels from Amazon as best deal for the quality at the time. I say the kit From WindyNation.com (he does free UPS delivery) and save the mounting stuff until you are ready. Meantime you can rig the two panels with hinges and legs and move them around until you become convinced of what a great asset it can be and mount them.

That said, this time I went much bigger (600 watts now and room for 400 more later if I ever need it) and used Renogy panels because they had a 100 watt that was 5 inches narrower than the WindyNation and I had a space issue.

Good luck. no going wrong with 6vs and you will love solar, any solar any way you set it up.

Did you do your own panel install on the roof? How did you get wiring down to your battery compartment? What did you use to go through the membrane and how did you seal it afterwards? I have a good idea how it's done, but wanted to see what actually is used, plus what actually works before punching holes for mounts. Also what gauge wire from the panels to the batteries? Thanks

**Flybob** · 06-11-2020, 07:44 AM

To answer your solar charger question. Do not waste money on a solar powered charger as they are generally marginally sufficient to keep a battery maintained with no load. Instead get a 100-150W solar panel and a controller. You can make a nice portable stand for it from 3/4" PVC so it can be positioned in the sun. Strategically glue only some of the joints so it can be disassembled and stored flat. I recommend getting a controller that is 2-3 time the capacity you think you need now. This will allow you to add panels if needed without the expense of another controller. Also don't skimp on wire size. Renogy.com has some good tutorials on sizing solar systems.

babock · 06-11-2020, 07:37 PM

Quote:

Originally Posted by Comanchecreek

Did you do your own panel install on the roof? How did you get wiring down to your battery compartment? What did you use to go through the membrane and how did you seal it afterwards? I have a good idea how it's done, but wanted to see what actually is used, plus what actually works before punching holes for mounts. Also what gauge wire from the panels to the batteries? Thanks

I have 4 175W panels mounted on my rubber roof. I made my own aluminum brackets with aluminum angle.

If you are putting panels on your roof, get the biggest panels you can. If I did mine over, I would buy some 300+W panels and just do fewer panels.

Personally, I would avoid Windynation.

I used a waterproof gland to bring my wires down through a bulkhead. Each of my panels goes to a combiner box and then 4 AWG(overkill), to a breaker, down to my controller with a transition to 6 AWG for my Victron controller. From my controller, it was 6 awg to a breaker and then 4 AWG to my batteries.

I did not waste my time with a PWM solar controller. Use an MPPT to get more efficiency.

babock · 06-11-2020, 07:51 PM

If you want to go the 200W solar suitcase route, buy 2 100W panels, connect them together with hinges and buy your own MPPT solar controller. Wire the two panels in series. Save some money and buy an Epever solar controller if you don't want to buy a Victron. Stay away from Renogy and Windynation. You get way more for your money with my first 2 suggestions.

https://smile.amazon.com/EPEVER-Upgr...1923207&sr=8-6

https://shop.pkys.com/Victron-Energy...th_p_2779.html

dave961 · 06-11-2020, 07:51 PM

I opted for 2 big AGM batteries. I also changed the charger/controller to a really good one so they will stay healthy for a long time. Added a 3000w inverter to the mix. No solar yet.

babock · 06-11-2020, 07:57 PM

Quote:

Originally Posted by dave961

I opted for 2 big AGM batteries. I also changed the charger/controller to a really good one so they will stay healthy for a long time. Added a 3000w inverter to the mix. No solar yet.

Your cables look way to small for a 3000W inverter. You need 4/0 minimum.

mnoland30 · 06-11-2020, 09:23 PM

I didn't want to punch a hole in my roof, so I ran a flexible plastic conduit down the front of my trailer. I used silicone caulking to attach the flexible panel to the roof. On my last camper, I couldn't get the solar panel off before I sold it. If I had it to do over again (and I will soon), I'd do it with a glass covered panel. I put in #8 wire because I thought I might expand the system later. Turns out, I could have gotten by with #12.

If you want more info than you will ever use, try this blog.https://handybobsolar.wordpress.com

babock · 06-11-2020, 09:39 PM

Quote:

Originally Posted by mnoland30

I didn't want to punch a hole in my roof, so I ran a flexible plastic conduit down the front of my trailer. I used silicone caulking to attach the flexible panel to the roof. On my last camper, I couldn't get the solar panel off before I sold it. If I had it to do over again (and I will soon), I'd do it with a glass covered panel. I put in #8 wire because I thought I might expand the system later. Turns out, I could have gotten by with #12.

If you want more info than you will ever use, try this blog.https://handybobsolar.wordpress.com

i didn't worry about punching any more holes since there are already dozens of holes for fans, AC, skylights, vents...

handy bob's website is a mess and out of date.

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