100 Watts Solar with Deep Cell 31s or Trojan 6 Volts

Under optimal conditions, with a 100 watt solar panel you will get 5 to 6 amps per hour or somewhere between 25 to 40 amp hours in a day. So with your lite usage and led lighting in most new TCs you will probably do fine, although I think most would recommend a second panel. With solar, your milage varies with the weather and how shaded the panels are. I would recommend that you put AGM batteries in the TC as they do charge faster than lead acid batteries. They also perform better in cold weather.

I put two 100 watt panels on our Adventurer TC. Like you we migrated from a 5th wheel. I have two group 27 AGM batteries. We try to conserve on the batteries, but since both my wife and I have CPAPs I wanted to make sure we had enough battery and the ability to recharge. Turns out the CPAPs only use about a combined 7amp hours a night and that is about 8% of the usable capacity of the two 89 amp hour AGMs

There are a number of discussions on solar in the forums. You might want to do a few searches.

Jim

Jim

If you start out with fully charged batteries then what you need to watch for is not to get behind the battery discharge curve.

The 100WATT solar panel will only produce around 5AMPS during high sun which will be only around 5-6 hours a day.

Battery science tells us if we discharge a 12VDC battery below 12.0VDC (appx 50% charge state) when you hit the 12VDC battery with 14.4VDC it will demand around 20AMPS of charge current for about 30 minutes and then start backing down as it gets charged and finally holds pretty steady around 6 AMPS or charging current after three hours of being charged.

As you can see from this if you get behind the charge curve the approximate 5AMPS of DC current being produced by the Solar Panel will not keep your charge up.

Just something to think about...

just for conversation I am planning to add three 120WATT panels to my off-road popup and this will give me around 18AMPS of DC current when in high sun.

If my batteries are 12.0VDC or lower this may not be enough charge current to get my battery bank recharged back up to its 90% charge state before I lose high high sun. In this case I will have to first start out with using my generator to get past the initial BOOST charge mode when I first hit them with 14.4VDC. My three 12VDC batteries want to see around 52AMPs of DC current when I do this. So my game plan is to run my generator for the first hour to get past this high charge rate and then the 18AMPS of DC Current available from the Solar Panels should be enough to give each battery in my battery around 6AMPS of DC Current and will get my bank up to its required 90% charge state before I lose the high sun.

Now granted my usage is pretty high with what we want to run when camping off the power grid which makes all of this alternative ways of charging to get my batteries back up to their 90% charge state so important so I can make it through the night. This is what I am going to have to deal with using my solar panels as well as my 2KW generator...

Just passing this along to get your mindset going on what to expect.

In your case if you only consume around 5AMPS of continues DC current for 6 or so hours this should be replaced by the one 100WATT solar if you are in high sun for the 6 hours.

In my case I will be consuming a good 1AMP for the 24/7 running my parasitic draws and then from like 6PM to around 11PM I will also be consuming around 20AMPS of DC current running a bunch of the things we want to have running from my batteries. My planned three 120WATT Solar Panels will not be able to keep up with this much current drain before I lose the high sun. Again in my case I will have to supplement the batteries re-charge using my generator to run my regular on-board smart mode charger for at least a good hour and then I can probably do ok with the solar panels if they remain in high sun until evening. This is what I will have to deal with.

In my case if I don't start my evening run off with my batteries with at least a 90% charge state I will not make it through the night to 8AM the next morning. Game over...

Just some of my thoughts on what to expect on your end. It takes planning for sure..

Roy Ken

Moved from Technology Corner

You're on the edge with only 100w solar, and 9 yo batteries. Trojan T105s are true deep cycle.