Forum Discussion

jimh406's avatar
jimh406
Explorer III
Apr 12, 2017

How much solar power do you have, wish you had?

I'm thinking again about adding solar to my truck camper. I generally don't need it, but still, it would be a nice to have to keep the batteries charged. I have LEDs and this would be mostly to charge batteries for running the furnace at night and minimal fan use during the day.

So the inevitable question comes up. How big should I go? This is important with minimal space on the roof that isn't otherwise occupied. I'd like to be able to go on the roof as needed with taking the panels off.

How much solar power do you have, wish you had?
  • fpoole wrote:
    So with that in mind, I'd double whatever is recommended due to poor sunlight, shade factors etc...

    I might go with another 160, four on the camper roof and as a last resort another set of batteries but I don't think I should have too, for some reason it's just not working as "I" think it should be (dealer installed), so the new controller is the first stop...

    Hope that helps...

    Solar is nice


    Hey Frank!

    From the photos I have seen on your system while upgrading your charge controller I would certainly upgrade your cables from your charge controller to battery bank, battery bank to inverter and convertor. Also I would balance your battery bank too. One of your photos shows your batteries separated by 3 feet or more. Also, review the distances between your charge controller and battery bank and invertor. There are maximum distances for optimum performance in these connections.

    b
  • bka0721 wrote:
    To answer your question, directly; I have 1,860 watts of Solar.



    On a TC? That's impressive. How did you manage that?
  • To answer your question, directly; I have 1,860 watts of Solar.

    Unfortunately the number of watts is not how one should decide when is enough enough. First, you need to determine what your needs are, then how many seasons are you going to need those needs and finally, do you have the landscape to accomplish all three "needs."

    As an example, if you left on voyage to Antarctica from the Bahamas would you just take off with a couple of shirts and shorts? No, should be your answer, your needs are going to change so you need to prepare for the worst case scenario. If you are going to use your TC for winter camping and summer camping, you will need a minimum 60% more capacity (watts/AmpH) than you would need just for summer only use. Also your uses, Laptop, stereo, furnace, TV and whether you will be camping in shady areas either by trees, buildings and or Canyon walls. Lots of things to figure.

    But, why can't someone just give a simple answer, sure; For the normal TC user for most typical use, 200 watts should be sufficient. I did testing over a 12 month period (I fulltime and have not plugged into electricity in over 7 years) where only the items in my TC were being powered by my AC/DC battery bank augmented by 200 watts of solar and 300 AmpH of AGM Lifeline Batteries. Well when I installed this initial phase I upgraded the wires and cables so to allow expansion. So, after a year I determined my minimal use of AC/DC demands 200 watts were fine and adding an additional 100 watts would negate any need to climb (read, dangerous) up on my roof to tilt and then untilt the two 100 watt solar panels. As well as make up the loss of watts/AmpH harvesting that occurs in the winter season. This is due to many factors, such as lower angle of Sun off horizon, shorter hours available for sunlight and most important, temperatures below optimum battery temperature of 55*F.

    So my summation is, 200 watts should work (don't get bigger than 100w panels to decrease issues with shading) with an extra 100w thrown in to insure you safety and AmpH loss during winter months.

    b
  • We have one 200 watt panel (no room for more) and 2 group 27 AGM batteries and have yet to need more, including running the furnace at night in the winter. So I am happy with what we have and really don't want any more. We have yet to use the generator except to exercise it.
  • I have played around with 90w of moveable solar panels and got good efficiency but always worried about them sprouting legs. This kept my enclosed trailer batteries topped off if the the trailer was disconnected from the camper which just powered the interior lights and water transfer pump.

    The new camper will have 480w of fixed solar. I expect about half that output due to where I live and camp. I'm more of an electric consumer than Frank, so I expect to to have top off more often with the generator even if I am connected to a large battery array.
  • I have (5) 100 watt panels and 425 Ah or 200 usableAh if you are willing to discharge that far. We don't. The setup has worked perfectly to run our fridge when the sun is out and power different AC appliances like coffee maker, crockpot, small vacuum cleaner, power tool batteries, laptops etc...

    A smaller system could probably do all this but I like to keep the batteries above 12.4 volts. The added panels gives us a decent charge even on cloudy days.
  • I have 300 watts charging two Trojan T-125s...240 amps. It is enough.
  • I have two 100 watt panels charging two group 31 AGM batteries. I use my LED lights and the fantastic fan and in the winter add in the heater fan. I am kind of maxed on roof space as I carry to kayaks up top so the panel's go on each side of the cab over hatch. In the few years of running this set up I have done fine.
  • Yah, good question certainly...

    I have 3x160w = 480-watts and 3sets of 2-6vt batteries.
    I feel I have enough, but need a new controller to manage it all

    While there are calculations that you can use, amps needed to run everything you need to run, I've sort missed all that.

    I just run TV/DISH/DVD and a laptop and I'm right at a breakeven maybe on a good sunny day.

    There will probably be those that say I have way too much, don't need it all etc, but it is what it is in everyday life. I have to run the Honda Gen and don't feel I should. Rarely get up to the 14.4 level and even fewer times to the "Full" charged level.

    So with that in mind, I'd double whatever is recommended due to poor sunlight, shade factors etc...

    I might go with another 160, four on the camper roof and as a last resort another set of batteries but I don't think I should have too, for some reason it's just not working as "I" think it should be (dealer installed), so the new controller is the first stop...

    Hope that helps...

    Solar is nice