Solar vs trickle chargers

Most would say to just keep up you need sunshine, and a couple of full size roof panels. Generally, under 100 watt panels are not really effective, but of course, every little bit counts.

UncleDonald wrote:
would a portable trickle charge type panel that sits outside do the job?

No. You can't expect a 0.4a battery charger that only works when the sun is out to keep up.

Trickle charging won't help you much beyond keeping batteries up in storage. If you want to keep the batteries up while boondocking indefinitely, you'll need a lot more. For my 220ah battery bank and usage of 25 to 35 amp hours between sundown and sunup, 200 tiltable watts on the roof and a PWM controller works great. But to know if that will work for you, you first need to know how many amp hours you typically use. Judging by how long your batteries last now, I'd guess you would be fine with 200 watts. But it's best to do the math. RV Solar 101

First: reduce your consumption as much as possible; if you haven't replaced all lights with LED, start there.

I have 2 60 watt panels permanently flat mounted on the roof with a $20 PWM controller. They will supply all our needs if we are in a clear spot with good sun and almost no need for the heater (have all LEDs and we are pretty careful).

I have a portable 100 watt panel without a controller that can be positioned to face sun, and can be up to about 100 feet from the trailer.

Using both systems we can almost always avoid using the generator unless we get a long run of no sun and/or need the heater a lot (more than a couple hours a day). We have had a couple of sites where it was so shaded that I couldn't even get the portable panel in the sun and had to use the generator after 4 or 5 days; can't win em all!!

Doug

Do yourself a favor and get 100w to 250w of solar. I prefer mounted on the roof but portable is fine if you do not mind the hassle or always park in the shade.

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smkettner wrote:
Do yourself a favor and get 100w to 250w of solar. I prefer mounted on the roof but portable is fine if you do not mind the hassle or always park in the shade.

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UncleDonald wrote:
I have a Coachmen tt with two 6v batts. After 3 or 4 days boondocking, running the lights, water pump, heater fan, etc, the batts get pretty low. Should I get a roof mounted solar panel or would a portable trickle charge type panel that sits outside do the job? Thanks, Don

Not much info there (how low is "pretty low" in volts?), but all solutions mean don't get the solar trickle charger.

If you don't want to nail a panel or two on the roof then you could have a portable solar set-up instead with enough wattage that would do you some good. You might also like to have a Honda 2000w gen.

Usually, it is a good plan to have some solar plus the Honda 2000w so you can keep on camping off grid whatever the weatherman delivers.

Can't suggest much without knowing more about the whole situation--how long off-grid is wanted?, can you carry more batteries?, etc.

Our current 5er already had solar but I added 1 - 150w panel and a mppt control on our last 5er. We've been dry camping a lot and I want to make sure there's power for my cpap. I thought long and hard about solar vs gen and decided that if solar works, I don't need to fuss with a gen. I never use the luggage rack so I mounted the panel on it to avoid more holes. On our first trip, I had to setup with the panel tilted to the north and it was partly cloudy every day. We ran all the (led) lights we wanted and used the furnace a little and the batteries (2-6v) were fully charged every afternoon. I will always have solar on my RVs from now on. Craig

You need 200 watts portable moving 2 or 3 times a day, or 400 watts mounted flat on the roof.

I have two 75 watt panels permanently mounted on the roof. They generally keep us in as much 12v as we could need, even when parked near trees. We generally watch a movie or two in the evening, and use the lights and water pump in a regular fashion. We definitely don't skimp. As long as there's no snow, they do a great job of maintaining the batteries all Winter too.