40w or 80w Solar Battery charger?

[Rod]

They make these nice "suitcase" chargers. most of my 12v usage is normal except for the water pump and heater. I plan to use generator/shore plug for large appliance 110v use etc. will the 40w do the job of trickle charging the battery daily? 2008 Jayco Jay series. new to RV camping but not to camping

https://www.amazon.com/gp/product/B0...k_ql_qh_dp_hza

[Mustang65]

Try the Renogy 100 watt panel kit, a few more watts to help out and a little cheaper. A lot of the members use them... great products, service and is expandable.

https://www.amazon.com/Renogy-Watts-...l+100+watt+kit

Don

[DanNJanice]

Originally Posted by Rod

They make these nice "suitcase" chargers. most of my 12v usage is normal except for the water pump and heater. I plan to use generator/shore plug for large appliance 110v use etc. will the 40w do the job of trickle charging the battery daily? 2008 Jayco Jay series. new to RV camping but not to camping

https://www.amazon.com/gp/product/B0...k_ql_qh_dp_hza

A lot depends on what you consider "normal" usage. The right way to determine this is to do an energy audit to determine how much energy you normally will be drawing from the battery(s). For example, does your trailer have LED lighting, or the original incandesant? Will you be using an inverter to power small 110VAC devices like the TV or computers?

[Rod]

I am replacing incandescent with LED and not planning inverter "AC" products use. I have inverter and 110v plugs in my TV and Gen for 110v use via RV.

[Mustang65]

Originally Posted by Rod

I am replacing incandescent with LED and not planning inverter "AC" products use. I have inverter and 110v plugs in my TV and Gen for 110v use via RV.

The biggest drain is the main heating. Depending on how cold it is outside will determine how much you drain the battery. For a standard 85Ah battery and a cold night, it will use up most of the 40ish Ah you can use of the (STANDARD) batteries 85Ah (it is called the 50% rule). If you calculate that out and say you did use 40Ah, you need to replenish that during the day. Given ideal SUNNY conditions (in 100% of the sun light, no clouds) if you get the 100Watt Solar panel, PWM Solar Charge controller, 4 hours of Fall/Winter/Spring productive sun light,
( Solar panel = 5.2 amp output x 12Volts (battery voltage) x 4 hours = 20.8Ah that the panel will put back into the battery. You can probably see where this is going, so the 1st day you will put back in 21Ah = about 60Ah available for night 2. So now on night 2 you may not make it through the night as you need to turn everything off when you battery voltage gets down to 12.0VDC. You will need to use a generator to assist the solar during the day to insure you get through the cold nights.

Summer should be no problem.

What ever you decide to do, you need to monitor the battery voltage. Pick up an inexpensive Digital Voltage Display and plug it into your 12VDC accessory outlet in the TT. Something like the one below... Amazon has all kinds

Don

[bankr63]

Depends on what you are trying to do. I have a 40W panel that is great for keeping the battery topped off while in storage; compensates for all the parasitic draws. I can park in storage for weeks and come back to a full battery.


It is also fine for camping over long weekends, but we are pretty sparse on our power usage and have converted our TT over to all LED lighting for living lights (navigation lights are still incandescent, but they are only on while travelling and hooked to the TV). I only use the built in indicator, but have never had power drop below 2/3 for a full 3-4 day weekend, which it drops down to pretty soon after setup, and on a good sunny day my solar controller will show the battery fully charge again by end of day.


If you are looking to go truly off-grid for longer periods (sounds like not really as you have a genny too) or winter camp, then you should get a bigger panel.