How much will adding solar help?

[Chuck_S]

Thank you. Are there other batteries that I should consider prior to jumping to lithium? Not sure if the expense would be worth it. I pay about $100/piece for the batteries I currently use.

I'd not be discarding good batteries but I switched to a pair 6v "golf cart" batteries in series. These are true deep cycles. Since they're 6v they have to be used in tandem pairs. Once connected they're just a big 12v battery and treated and charged as such.

Trojan T145 has an RC of 530 minutes (at 25amps) or 221 useful amphours. T125 has an RC of 488 and 203 useful amp hours. Based on the 25 amp draw this this the very conservative number for me but very useful for these power hungry campers with high amp draw refrigerators. RC/2.4=Useful amp hours.

Lithiums are better and terribly more expensive. Even my setup is overkill for the vast majority of our camping -- but overkill always works.

-- Chuck

[camaraderie]

I agree that a generator remains the best solution for the amount of use you would get from solat. Since you have THREE batteries of hopefully group 27,,,that would be 300 amp hours or 150 USABLE amp hours before you NEED to recharge to avoid battery life cycle damage. Your 300 amphour bank can ACCEPT about 60 amps of current during bulk charging. If your converter is that size or a bit larger ...good... but it is still gonna take you SIX hours at least to put a full charge back in EVERY time you recharge. This is where solar would be of most benefit to you I think since the sun works all day and once you get to 80% full in a couple of hours...a 200 watt set up can provide the final 50 amp hours of charge over the course of a sunny say. Still not an investmet I'd make for a week a year...but 3 or 4 hours less noise a day might be worth it to you.
Good luck!

[tomkatb]

The question is sort of complex.

You likely use 150 AH of battery a day which you have. Thus on a travel day(assumes a trailer or fifth wheel) you will likely drain the batteries before the following morning. Charging will be necessary the next morning.

Thus you should at least double the battery capacity.

A 100 watt solar panel generally provides 25 AH on its best day. If you live in the Midwest there are few days like that. Also trees are the enemy. A 1000 watt solar panel could supply 250 AH on its best day. Some to recharge the battery and supply your daily needs.

You will not like the price.

Virtually any generator would provide enough power to keep up. 3-6 Hours a day.

Adding a big residential fridge makes boondocking hard. A small solar panel would be a good teaching item. They also keep your house batteries charged over the winter if it does not snow a lot where you park. Nice to top up the batteries.

[TitanMike]

One reason the suggestion of Lithium batteries comes up when residential refers are discussed is the fact they recharge typically in one third the time.

Running a generator z couple hours in morning and couple hours in evening can leave lead/acid batteries undercharged. This not only cuts run time but also shortens battery lifespan.

Lead acid batteries usually take 6-10 hours of charge time depending on converter, battery bank size, and dept of discharge.

Charging Lithium batteries is pretty straight forward. Use 150 ah, charge for 3 hours @50 amps, and mostly done. Maybe 30 minutes od absorption charge.

Same benefit with solar. When sun is full and directly overhead no wasted energy waiting for the electro-chemical reaction in the lead acid battery to store the power. Also, lead acid battery charging current tapers over time. Lithium batteries draw as much current as the charger will put out until it reaches over 90%.

[bhersh]

This is all great information. I appreciate it and I welcome any additional input! Thanks!

[PhilFromMaine]

Originally Posted by bhersh

Hello. We dry camp at the beach at least one week each summer. We have a residential fridge in our Chaparral 391qsmb. I run 3 standard deep cycle batteries. I run the generator in the morning and evening to charge the batteries. The batteries get pretty drained overnight and throughout the day. I was curious how much adding solar panels from HF or Amazon (nothing crazy $$) would help? Let me know your thoughts. TIA

Solar helps a lot as long as there is sun and you have enough wattage and storage (battery banks).

However, when you have nearly a month of cloudiness and rain like we have had here in Maine, You will need a back up source of power like a generator or a DC-DC charger that will supply power from your vehicle alternator via the vehicle battery.

[acadianbob]

It's not always just about the monetary issue. Solar is much quieter of course. Good for you and your neighbors. We have a residential fridge and inverter. Two Group 27 AGMs in parallel. We have a 140W suitcase solar. It puts out 7 amps DC. Does a good job of keeping our batteries topped off during the day. Minimizes the amount of generator time. Additionally, lot of places limit generator time.

[bhersh]

Originally Posted by PhilFromMaine

Solar helps a lot as long as there is sun and you have enough wattage and storage (battery banks).



However, when you have nearly a month of cloudiness and rain like we have had here in Maine, You will need a back up source of power like a generator or a DC-DC charger that will supply power from your vehicle alternator via the vehicle battery.

Yep. I'm all set with generators. Just looking to minimize using it.

[Rolland]

Originally Posted by bhersh

This is all great information. I appreciate it and I welcome any additional input! Thanks!

Completely agree, I’m also thankful and learning from the discussion!

[GravelRider]

Originally Posted by PhilFromMaine

Solar helps a lot as long as there is sun and you have enough wattage and storage (battery banks).

However, when you have nearly a month of cloudiness and rain like we have had here in Maine, You will need a back up source of power like a generator or a DC-DC charger that will supply power from your vehicle alternator via the vehicle battery.

You can also oversize your solar so that you'll still be able to keep your batteries charged even if rainy or in shade. If you size your solar based on ideal conditions, you'll nearly always be disappointed.

[Comanchecreek]

Your camping neighbors will certainly be glad you installed solar. Sounds like you'll need to go whole hog if you want to be successful with your install. Running a resi' fridge is no small requirement for any system running on batteries.

[doanshop]

Originally Posted by NMWildcat

For one week a year? Keep running the generator........

I have a residential fridge in my camper I did the solar 300watts 2 100amp lithium batteries . If I had it to do all over I would I would just do the Lithium batteries and run the generator .I have the champion 3500w- 3200 w remote start and love it. I have to agree run the generator forget solar .cloudy days parked in shade sun a wrong angle solar sometimes does not work that great in winter time it is fine. But in summer time you want shade . Just my thoughts hope this helps .I also boon dock a lot solar does not help me that much running gen batteries 100% charge in 4-6 hours off gen .

[tsunyday]

we have a rockwood mini lite. which came solar ready. We have generators and solar suitcase. the only thing the solar does for us is keep the battery charged, nothing runs on it except what would normally run on batteries. the suitcase is HEAVY too. On the other hand the generators will run everything, including microwave and AC (tho not at same time).we have 2 Sportsman dual fuel generators that are small(under 50# about 21" x 19" and can be piggy backed together or used separately(together for AC).https://www.homedepot.com/p/Sportsma...B&gclsrc=aw.ds Good luck and happy camping.

[tomkatb]

ditto the residential fridge thing.

The math! Owners report that 100 watt solar panels on the roof of the rv will produce 25 or so ah total per day. North america is too far north. Bad sun angle.

And, that is on their best day. Any sun or trees knocks that down.

Since a large residential fridge needs close to 200 ah per day in the summer that would require 8 solar panels on the roof to stay even assuming perfect weather and no trees. You should have a minimum of 400 ah of batteries so you could go 2 days with no sun. Common in the midwest. Actually much more. Rained for a week in Ohio about a week ago.

[GravelRider]

Originally Posted by doanshop

I have a residential fridge in my camper I did the solar 300watts 2 100amp lithium batteries . If I had it to do all over I would I would just do the Lithium batteries and run the generator .I have the champion 3500w- 3200 w remote start and love it. I have to agree run the generator forget solar .cloudy days parked in shade sun a wrong angle solar sometimes does not work that great in winter time it is fine. But in summer time you want shade . Just my thoughts hope this helps .I also boon dock a lot solar does not help me that much running gen batteries 100% charge in 4-6 hours off gen .

Your solar panels are WAY undersized for your battery bank, and running a residential fridge, so I don't know that your solar assessment is quite fair. With a properly sized solar array for your needs, you may find that you are quite happy with it.