Help w/ basic solar setup

[et2]

My wife and I have made it over 10 years of rving without the need of solar. Now with our new trailer, which this will be our 3rd camping season, we want to go off grid for 4 days in N. MI to a music festival. We will not be needing any AC, microwave, hairdryers, tv or anything else 120 volts. What we will be using daily is:
10.7 cu.ft. Ever chill 12 v. frig, 3 amp draw
MaxxFan deluxe rooftop fan/exhaust, 3amp draw, maybe 8 hours
Endless Breeze box fan, 3amp draw, 8 hours
On board water pump for sink usage
Indoor trailer lights in the evening when not out listening to music
My battery is the original that came with the trailer, 1- group 24, 100 amp hour deep cycle.
I know I will need a new battery and a portable solar panel. And that’s all I know. I don’t see us changing our camping lifestyle and going off grid multiple times during the year so I want to keep the setup simple. With a single new battery and a solar panel is it even do able?
Any help and suggestions would be great. And TIA.

[IPcamper]

Well, you have listed over 120Ah per day electric demand. You are going to need more battery capacity. If your existing battery is a lead acid battery, then it only has 50Ah usable capacity before it drops below 50%. I would guess you will need 200 to 300Ah capacity. That would get you two days with out any charging, rainy days are not good for charging. LiFePO4 are more expensive but charge faster and have more capacity/weight. Golf Cart batteries have capacity, less expensive, but are heavy. As for panels, If you want portable panels, Renogy and others sell Suitcase style panels with charger controllers. Typically they are 100W or 200W sets. These would connect straight to your batteries. A 200W panel might give you 84Ah a day, if the weather is really good. 400W of panels is probably more realistic, and gives you a little margin. Some people on YouTube have shown how to take individual panels and make their own portable solutions for larger capacity and lower costs. The cheapest solution is to add a second battery to ensure capacity during the night and purchase a small generator to charge your batteries up during the day. Take time to investigate some options, a lot to choose from.

[TacomaJoe]

Ballpark wild guess, you are consuming 150Ah or more a day. You need about 400W of solar panels to recharge each day (with decent sun). More battery for sure.

[MillMitch]

I was in a similar situation last summer. Had a voicemail 4 weeks before a trip that indicated electric was out at our reserved site and might not be fixed by then. If your festival is a little away from the campsite, you might get a small generator and run it during the day while you are at the festival. We picked up a WEN 2350. I don't have the electric fridge, but am thinking if the batteries are fully charged at night and you turn off the lights and water heater (gas and electric), you could get through the night since the fridge won't be opened and therefore won't cycle as often. I also picked up some rubber coated steel cable and locked the gen to a tree (or camper) during the day.
Another advantage to the gen for me was being able to work on the camper at the storage facility and run my power tools, rather than drag it back to the house.
Good luck and have fun.

ps: we're running on our original size 24 battery w/ 2018 travel trailer. Removed during winter, and topped off each spring.

[et2]

Thanks all for your helpful responses. I now see now that to find your usage you add up the listed amp draw from products and multiply that by estimated hours used. Like I said I’m very new to solar and batteries. I’m stuck with lead acid or agm batteries as my power center doesn’t handle lithium-ion batteries. What’s the difference between using the furion solar prep port on the outside of the tt or wire solar panels directly to the batteries? Again TIA,

[bikendan]

Your signature says you have a 2021 Salem TT. Its converter should be LiPo capable. You need to check with the converter manufacturer.

Sent from my SM-G781U using Forest River Forums mobile app

[BehindBars]

Originally Posted by et2

Thanks all for your helpful responses. I now see now that to find your usage you add up the listed amp draw from products and multiply that by estimated hours used. Like I said I’m very new to solar and batteries. I’m stuck with lead acid or agm batteries as my power center doesn’t handle lithium-ion batteries. What’s the difference between using the furion solar prep port on the outside of the tt or wire solar panels directly to the batteries? Again TIA,

I’m new to RV solar, too. I’m beginning a solar installation on my little toy hauler today. To test myself, let me attempt to answer, and experienced people can by all means correct me if I’m wrong.

The answer to your question is you do not connect solar panels directly to the battery in either case. There needs to be a charge controller between the two. So if you use the solar prep kit on the side of the TT, your portable panel setup will include a built-in controller. If you put panels on your TT roof, you will install a controller inside somewhere between the panels and the battery.

We have a solar prep socket on our motorhome and it is nothing more than a 2 pin connector wired straight to the batteries. While the connector could be useful in some cases, it is there mostly as marketing flimflam, in my opinion.

[et2]

Originally Posted by bikendan

Your signature says you have a 2021 Salem TT. Its converter should be LiPo capable. You need to check with the converter manufacturer.

Sent from my SM-G781U using Forest River Forums mobile app

I had previously spoken with manufacturer and my model is wf8735pb which does not auto detect different batteries. If it were wf8735 ad it would auto detect batteries.

[Old Coyote]

et2,
We use our TT (see bottom of post) as you describe, with the same refrigerator and similar useage. We have a 250AH LiFePO4 (Lithium) Battery, a 190watt Solar Panel on the roof, and deploy a 200 watt Portable (Renogy) Suitcase (plugged into the SAE ("Solar on the Side" port).

The Portable Panel on the ground is connected with a 50 ft 12 AWG cord that allows a large range of movement, and aimed at the sun for maximum output.

We are able to boondock (in the west, where sunshine is usually plentiful) for 5-7 days WITHOUT using our 3000 watt generator to recharge the Battery. The Solar Panels recharge the LiFEPo4 Battery quickly, usually to full SoC (state of charge) by sundown on a sunny day. The extra capacity of the Battery allows for cloudy or rainy days.

It is VERY useful and wise to add a shunt style Battery Monitor (Renogy or similar) to the negative post of your battery to monitor power useage and Battery SoC. Also note that even if your 120VAC-12VDC Converter Charger is NOT specifically setup to charge LiFePO4 batteries that the Solar Panels WILL do so (supplying the higher Voltage, ±14VDC required), even when using a generator or shore power.

We usually run out of fresh water and/or food before we run out of battery power.

[Aussieguy]

invest in 2 panels around 400w of panels
+ a Lithium battery 100-200 ah


12v fridge and the Hybrid deep cycle lead acid from the dealer is only good for a day maybe two if you push it.

solar will charge lead acid but it is slow.

either roof or ground mount the panels
They will top up the battery enough each day as you camp
weather and location permitting

Your converter
if NOT auto detect?
you may have to switch manually using the tiny dip switches

OR if the converter is not able to do lithium but will charge AGM
it is able to charge the lithium to almost 100% .... then let the solar top it off
Lithium does not require the battery to topped up 100% ever day . Only needs it to be fully charged once /twice a month

You could use a generator as others mentioned
but with moderate solar and your camping style you won't have worry about running out of gas , generator theft, gas storage .

set it up on solar and just leave it ......


would not invest in dc-dc charger at this point.
get one later on , if you decide you like off grid camping .

you can hook up the truck 7pin to get some charge if desperate

[et2]

Again thanks for the replies. I’m not understanding how lithium batteries would work at all for me if my tt power center/convertor can’t be used with lithium batteries? What am I missing

[Yoods]

Originally Posted by et2

Again thanks for the replies. I’m not understanding how lithium batteries would work at all for me if my tt power center/convertor can’t be used with lithium batteries? What am I missing

I am not familiar with the particulars of your TT but your stock charger should work with a LifePo4 battery. The difference would be in the charging capacity; set-up for charging LA, not Lipo batteries

I recently talked directly with WFCO tech support about upgrading from our 2019 stock WFCO convertor in our A-Frame to a WFCO LifePo4 capable charger (auto-detect). I was told that the stock WFCO convertor would charge the Lipo battery to about 80-85% You would have to find other means to get it to 100% (shore power plug-in LifePO4 capable battery charger, generator, solar).

I hope this helps in your understanding. It certainly helped me to know I did not need to worry about it and know how I could top off the Lipo battery to 100% when needed.

[TitanMike]

Originally Posted by et2

Again thanks for the replies. I’m not understanding how lithium batteries would work at all for me if my tt power center/convertor can’t be used with lithium batteries? What am I missing

There is no reason a regular power center converter can't be used with lithium batteries.

It just won't charge them above around 90% ((unless you have a Progressive Dynamic's converter with Charge Wizard and Pendant which lets one force a Bulk rate of >14v after regular charge cycle has completed.

Even if no PD converter solar will satisfy the need to top off and balance cells as well as a battery maintainer that can be attached to batteries and left plugged into a nearby 120v outlet that's hot when shore power is available.

One does not HAVE TO upgrade the converter, it just eliminates the need to rely on supplemental means of topping off.

A good battery maintainer capable of charging LiFePo4 batteries (several brands available) can cost as little as $30 with a NOCO Genius 2 amp selling for $49 on Amazon.

Again, a smart charger/maintainer can be permanently connected to batteries and left plugged in. Will only chargevwhen 120v is present and will work alongside the converter with no conflict.

[Old Coyote]

Originally Posted by TitanMike

There is no reason a regular power center converter can't be used with lithium batteries....

One does not HAVE TO upgrade the converter, it just eliminates the need to rely on supplemental means of topping off.

A good battery maintainer capable of charging LiFePo4 batteries (several brands available) can cost as little as $30 with a NOCO Genius 2 amp selling for $49 on Amazon.

Again, a smart charger/maintainer can be permanently connected to batteries and left plugged in. Will only chargevwhen 120v is present and will work alongside the converter with no conflict.

To Clarify, I believe Titan Mike meant that you DO NOT HAVE to upgrade your converter charger

Our TT (similar to yours) also has a WFCO 8735 Converter Charger which only charges the LiFePO4 Battery to about 80% SoC, but either or both of our Solar Panels, easily and QUICKLY charges the battery to 100% SoC (±14.6VDC).

You should be aware that for your WFCO 8735 C-C to charge your LiFePO4 Battery to 80% SoC, when USING a GENERATOR or SHORE power, you will need to occasionally (every 3-4 hrs?) cycle the WFCO 8735 OFF and the ON again by turning the 120VAC Circuit Breaker that power it OFF, wait a minute, and then ON again. This is because the WFCO uses a charging process that puts it into a VERY SLOW MODE/Rate (after 3-4 hrs?) that is only suitable for Lead/Acid batteries. Cycling it ON and OFF forces the WFCO to cycle back to the beginning of it's process to charge at a higher rate, that a LiFePO4 battery can easily manage.

[BehindBars]

Originally Posted by TitanMike

There is no reason a regular power center converter can't be used with lithium batteries.

It just won't charge them above around 90% ((unless you have a Progressive Dynamic's converter with Charge Wizard and Pendant which lets one force a Bulk rate of >14v after regular charge cycle has completed.

Even if no PD converter solar will satisfy the need to top off and balance cells as well as a battery maintainer that can be attached to batteries and left plugged into a nearby 120v outlet that's hot when shore power is available.

One does not HAVE TO upgrade the converter, it just eliminates the need to rely on supplemental means of topping off.

A good battery maintainer capable of charging LiFePo4 batteries (several brands available) can cost as little as $30 with a NOCO Genius 2 amp selling for $49 on Amazon.

Again, a smart charger/maintainer can be permanently connected to batteries and left plugged in. Will only chargevwhen 120v is present and will work alongside the converter with no conflict.

Thanks. This is really good to know and it makes sense. I have a WFCO 8725 in my small trailer, but if I switch the battery to lithium, the solar can handle final charge duty, as Old Coyote also pointed out.

[et2]

OK, now I’m getting it. Thanks so much. I do remember now the rep for my power center saying maximum charge to 85% and he then steered me towards agm batteries. I believe it was due to upfront costs me not sure how often I’d be using solar.

[TitanMike]

Originally Posted by Old Coyote

To Clarify, I believe Titan Mike meant that you DO NOT HAVE to upgrade your converter charger

Our TT (similar to yours) also has a WFCO 8735 Converter Charger which only charges the LiFePO4 Battery to about 80% SoC, but either or both of our Solar Panels, easily and QUICKLY charges the battery to 100% SoC (±14.6VDC).

You should be aware that for your WFCO 8735 C-C to charge your LiFePO4 Battery to 80% SoC, when USING a GENERATOR or SHORE power, you will need to occasionally (every 3-4 hrs?) cycle the WFCO 8735 OFF and the ON again by turning the 120VAC Circuit Breaker that power it OFF, wait a minute, and then ON again. This is because the WFCO uses a charging process that puts it into a VERY SLOW MODE/Rate (after 3-4 hrs?) that is only suitable for Lead/Acid batteries. Cycling it ON and OFF forces the WFCO to cycle back to the beginning of it's process to charge at a higher rate, that a LiFePO4 battery can easily manage.

Yes, the "not" should be there. I went back and checked my original post and it's there. Strange????

[TitanMike]

Originally Posted by et2

OK, now I’m getting it. Thanks so much. I do remember now the rep for my power center saying maximum charge to 85% and he then steered me towards agm batteries. I believe it was due to upfront costs me not sure how often I’d be using solar.

I recently ran across a " battery dealer" that steers everyone away from Lithium. Even goes as far to hand out a scare flyer he typed up himself which is more "fertilizer" than fact.

Turns out his real agenda is based on permitting and shipping fees for lithium batteries. Not danger, etc.

[jlynn721]

Originally Posted by et2

My wife and I have made it over 10 years of rving without the need of solar. Now with our new trailer, which this will be our 3rd camping season, we want to go off grid for 4 days in N. MI to a music festival. We will not be needing any AC, microwave, hairdryers, tv or anything else 120 volts. What we will be using daily is:
10.7 cu.ft. Ever chill 12 v. frig, 3 amp draw
MaxxFan deluxe rooftop fan/exhaust, 3amp draw, maybe 8 hours
Endless Breeze box fan, 3amp draw, 8 hours
On board water pump for sink usage
Indoor trailer lights in the evening when not out listening to music
My battery is the original that came with the trailer, 1- group 24, 100 amp hour deep cycle.
I know I will need a new battery and a portable solar panel. And that’s all I know. I don’t see us changing our camping lifestyle and going off grid multiple times during the year so I want to keep the setup simple. With a single new battery and a solar panel is it even do able?
Any help and suggestions would be great. And TIA.

A generator would make more sense. You will need 200w of solar (and a full day of sunshine) to get your battery to near full. A 2000w generator should charge your battery in a few hours. Plus, you could run the generator when the sun is down in the evening, in the morning before the sun is high enough to do any good with the solar.

[bobm253]

Here's a different idea ( which I am considering.) It may be expensive to do but how about using a 1500 watt or more power station (like a jackery). Plug your camper right to that unit via your shore power cord and do what you want with your appliances. You could then use your generator when ever needed to recharge the power station. I understand that it only takes a couple of hours to go from 0 to 100 percent and you're back in business. If you use less than that it would be shorter.

It may not be that cost prohibitive considering the cost of a solar install, new batteries etc.

Just a thought