We are just looking for a small affordable solar system. This would be used to recharge a GRP 31 deep cycle battery ONLY. We just want it for lights and maybe rechargeable items. What would be good for wattage? 100 watts? 50? PWM controller? We will use the generator for all the power hogs onboard. ThxWe dont use power hungry items while boondocking, we have LED lighting, and would use propane or campfire for cooking. If we need the A/C we will be in a rv park. We dont want to get an inverter and just want solar to recharge the group 31 deep cycle. We just dont need a lot of solar or the expense of a big system

suprz wrote:We are just looking for a small affordable solar system. This would be used to recharge a GRP 31 deep cycle battery ONLY. We just want it for lights and maybe rechargeable items. What would be good for wattage? 100 watts? 50? Pcm controller? We will use the generator for all the power hogs onboard. ThxIn May at 49N sunny all day I measured an AH haul of 56AH with a 130w panel lying flat. That would bring your battery up from 50% SOCHowever--- 1. You will be using your battery all day too, 2. It is not sunny all day every day3. It is not May all year4. An RV has wheels so you will not be at the same latitude all year.So it is a total WAG, but 200w flat might be enough most times, and you do have a generator for recharging via converter if not enough sun at times.You can use a PWM controller with the 200w. An MPPT will only do a little better (maybe!) and will likely cost more.

Mobile-solarpower.com is a wealth of info on solar stuff. 100 watts would work with an MPPT controller. Better would be 200 watts, for those rainy days.

Your energy survey indicates you need..batteries? Solar panels? Controller?Lights? LED, incandescent, florescent? PCM controller? Must be a new type.This might work but you’ve provided no numbers. https://www.windynation.com/Polycrystalline-Solar-Kits/Windy-Nation-Inc/WindyNation-200-Watt-12-24V-Polycrystalline-Solar-Panel-Complete-Kit-with-LCD-Solar-Controller-RV-Boat-Of/-/631?p=YzE9NDY=

BFL13 wrote:suprz wrote:We are just looking for a small affordable solar system. This would be used to recharge a GRP 31 deep cycle battery ONLY. We just want it for lights and maybe rechargeable items. What would be good for wattage? 100 watts? 50? Pcm controller? We will use the generator for all the power hogs onboard. ThxIn May at 49N sunny all day I measured an AH haul of 56AH with a 130w panel lying flat. That would bring your battery up from 50% SOCHowever--- 1. You will be using your battery all day too, 2. It is not sunny all day every day3. It is not May all year4. An RV has wheels so you will not be at the same latitude all year.So it is a total WAG, but 200w flat might be enough most times, and you do have a generator for recharging via converter if not enough sun at times.You can use a PWM controller with the 200w. An MPPT will only do a little better (maybe!) and will likely cost more.Good answer. We spent 4 days at Lake Havasu and had minimal gen time for microwave. Batteries recharged each day for lights, water pump, furnace fan, and a couple of hours of satellite receiver and television. Batteries were recharged every day.

I run 200 watts of solar with MPPT controller and my batteries (A pair of GC2's) are always fully charged by early to mid afternoon.I would go with 200 watts if I were you.

Looking for solar info UPDATE | Good Sam Community

BFL13
Explorer II
Feb 18, 2020
suprz wrote:
We are just looking for a small affordable solar system. This would be used to recharge a GRP 31 deep cycle battery ONLY. We just want it for lights and maybe rechargeable items. What would be good for wattage? 100 watts? 50? Pcm controller? We will use the generator for all the power hogs onboard. Thx

In May at 49N sunny all day I measured an AH haul of 56AH with a 130w panel lying flat. That would bring your battery up from 50% SOC

However---
1. You will be using your battery all day too,
2. It is not sunny all day every day
3. It is not May all year
4. An RV has wheels so you will not be at the same latitude all year.

So it is a total WAG, but 200w flat might be enough most times, and you do have a generator for recharging via converter if not enough sun at times.

You can use a PWM controller with the 200w. An MPPT will only do a little better (maybe!) and will likely cost more.
naturist
Nomad
Feb 18, 2020
Mobile-solarpower.com is a wealth of info on solar stuff.

100 watts would work with an MPPT controller. Better would be 200 watts, for those rainy days.
Lwiddis
Explorer II
Feb 18, 2020
Your energy survey indicates you need..batteries? Solar panels? Controller?

Lights? LED, incandescent, florescent? PCM controller? Must be a new type.

This might work but you’ve provided no numbers. https://www.windynation.com/Polycrystalline-Solar-Kits/Windy-Nation-Inc/WindyNation-200-Watt-12-24V-Polycrystalline-Solar-Panel-Complete-Kit-with-LCD-Solar-Controller-RV-Boat-Of/-/631?p=YzE9NDY=
EV2
Explorer
Feb 18, 2020
BFL13 wrote:
suprz wrote:
We are just looking for a small affordable solar system. This would be used to recharge a GRP 31 deep cycle battery ONLY. We just want it for lights and maybe rechargeable items. What would be good for wattage? 100 watts? 50? Pcm controller? We will use the generator for all the power hogs onboard. Thx

In May at 49N sunny all day I measured an AH haul of 56AH with a 130w panel lying flat. That would bring your battery up from 50% SOC

However---
1. You will be using your battery all day too,
2. It is not sunny all day every day
3. It is not May all year
4. An RV has wheels so you will not be at the same latitude all year.

So it is a total WAG, but 200w flat might be enough most times, and you do have a generator for recharging via converter if not enough sun at times.

You can use a PWM controller with the 200w. An MPPT will only do a little better (maybe!) and will likely cost more.

Good answer. We spent 4 days at Lake Havasu and had minimal gen time for microwave. Batteries recharged each day for lights, water pump, furnace fan, and a couple of hours of satellite receiver and television. Batteries were recharged every day.
Boon_Docker
Explorer III
Feb 18, 2020
I run 200 watts of solar with MPPT controller and my batteries (A pair of GC2's) are always fully charged by early to mid afternoon.
I would go with 200 watts if I were you.
dieseltruckdriv
Explorer II
Feb 18, 2020
In the summer and in full sun, 200 watts is enough for us. Later (October) in the year and cloudy days, it wasn't. I currently have 300 watts on the roof, and have 200 more to add this spring. I am using a Renogy Wanderer 30 amp PWM charger, it cost about 30 bucks. For panels, I am using HQST 100 watt panels.
I installed a Victron pure sine wave inverter for the tv, since that is all we use that isn't 12 volts or propane powered.
naturist
Nomad
Feb 19, 2020
Of course, “more is better.” More solar panels, for overcast skies/shady campsites, and hey, battery is fully charged by lunchtime (sunny day), so wouldn’t it be great to have more battery, and next thing you know there’s 2,000 watts of panels feeding 600 amp hours of batteries so you can run a small AC overnight . . . .
pianotuna
Nomad III
Feb 19, 2020
600 amp-hours of 12 volt batteries is not going to run even the smallest of air conditioners for very long.

Do an energy audit. From that size the battery bank. Then add solar charging.
Gulfcoast
Explorer
Feb 19, 2020
I don't have solar yet, but I don't see how 200-watts would be enough in the winter to run my furnace (I like it warm), lights, pump, tv, laptop and internet booster.

I now use my Champion inverter generator with golf cart batteries.
pianotuna
Nomad III
Feb 19, 2020
200 watts x 3 hours = 600 watt-hours. That's about 1/2 the capacity of a single group 27 deep cycle jar. It assumes an MPPT charge controller is used.

My furnace would use about 96 watt-hours if running constantly for one hour.

One might "squeak by" with 200 watts--but 400 would be a better choice.