Plug and play solar charger for small ATV's, car, etc.

Steven Lake
Steven Lake Solar Expert Posts: 402 ✭✭
Ok, I'm looking for opinions again for another solar setup. Currently all my other mobile and stationary rigs (several of which you guys helped me build with your recommendations, so thank you hugely!) are tied up in other jobs (cabin, house, etc), and I can't yank any of them for this job. Mostly because they're all installed in place and too big to easily move. So I need advice on a new rig. But this one is simple. I need to have a small solar charger that is pretty much "plug and play" (ie, pull out of box, hook to battery, walk away) in the 10-20 watt/12vdc department for use on up to a 60ah battery. I'm finding myself more and more having to haul out the 1kw genset for remote recharging jobs that could probably be better served (and ultimately more cheaply) by a portable solar charger. But since this will potentially be handled by farm hands and other family members (ie, others besides myself) who haven't got a bloody clue about this stuff (I'm the only one in the family who understands this tech) I need it as simple as possible to use. Hence my "needs to be plug and play" comment. I'd prefer it to have battery clips on the power side, but if it's only a cigarette charger I can always improvise. (that's what farmers do, isn't it? lol) I simply need a device that can do the whole horse and pony show (ie, solar panel and charge controller) in one package and is newbie friendly. Any suggestions?

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Plug and play solar charger for small ATV's, car, etc.

    How much current do you want to get out of it? And these batteries are not of the deep cycle type so you just want to bring them up to automotive Voltage levels then leave off feeding them heavy current? How regulated does it have to be?

    For example a 60 Amp hour 12 Volt battery could take 10 Amps for a bit but a smaller battery would be unhappy with that. 20 Watts might kick out 1.5 Amps or so.

    I actually have one of those small battery maintainer panels connected to the ride-on at the cabin. It has cig lighter output, but you can buy adapters to go to clips (which is how I have it hooked up). The current is so small that the limited sun over Winter is in no danger of doing anything more than keeping the battery up.

    Really for short term "get it going" charging a big panel feeding 5% to 10% current will work without regulation. You only have a problem if they leave it on. Likewise for long-term the opposite route can be taken; small panel keeps it charged but not enough power there to boil it dry.

    Tiny panel: http://www.canadiantire.ca/AST/browse/Green/EnergyConservation/RenewableEnergy/PRD~0112001P/Blue+Planet+1.8W+Solar+Battery+Maintainer.jsp?locale=en
    Bigger panel: http://www.solar-electric.com/so55wamusomo.html

    It's unfortunate that small-scale solar is pretty expensive per Watt.
  • Steven Lake
    Steven Lake Solar Expert Posts: 402 ✭✭
    Re: Plug and play solar charger for small ATV's, car, etc.

    Well, the applications vary. Most of the stuff we'd be using it on can take between 2-5amps dead in the face for an hour or more and not bat an eye. But just for simplicity's sake, 1-2amps, being the lowest common denominator, would probably be best and safest when dealing with the occasional small cell. Now your idea of using just a raw panel does sound tempting as these would be temporary applications and it's uber simple. Might have to look into that option.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    Re: Plug and play solar charger for small ATV's, car, etc.

    You probably should use Anderson PowerPole or like connectors (even 125 VAC twist lock or other 'non-standard' around the ranch type connectors). You don't want to trust people clipping the panels (or charge controllers) on backwards (panels are big old diodes and conduct very nicely when connected backwards).

    Charge controller--Since nothing is "for sure" in that type of environment--get a simple MorningStar sealed charge controller and bolt it directly to the solar panel frame:

    http://www.solar-electric.com/stpwmchco.html

    If you get the "fixed voltage type" (i.e., 12 volt only vs 12/24 volt)--They should just plug and play with the battery bank... (if you get a 12/24 unit, or a more complex unit, you probably should connect battery first, then connect solar panel. Wiring would should probably be in conduit or cover back of panel (sheet metal, metal screen, etc.) to keep critters from tasting your setup.

    You might think about making some sort of stake/stand for the solar panel (and battery case?). Hold it pointing at the sun above the low grass in the spring and keep it from blowing over (and breaking glass) in windy weather.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Steven Lake
    Steven Lake Solar Expert Posts: 402 ✭✭
    Re: Plug and play solar charger for small ATV's, car, etc.

    After thinking about this I've decided to build a wheelie housing (ie, a box with wheels and a pull handle) for this. 1) to protect the solar panel, 2) to make it easy to move, and 3) to include the wires in an easy to get to box at the bottom. This will do to start with, and could later be adapted with additional stuff like a battery and inverter should that be required at a later date. But for now I think I'm gonna take Cariboocoot's idea of just using a raw panel for what I need and build up from there if that setup proves insufficient for what I need. Thanks for the suggestions guys.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Plug and play solar charger for small ATV's, car, etc.

    to make it dummy proof is tough, but i'm thinking just a + and - from the pv to connect to the outside of a box to house the battery and a small controller such as a pwm sunsaver and fuses (all internal for you to access only) and exiting to connections again on the box to go to the battery. the output can be permanently wired by you just to keep anybody else from reversing the polarity there, but they still might do this at the battery so placing a 3a or 6a diode (if you go really large in pv or just have one available) across the + and - output leads (have it + to + and - to - or you blow the fuse and possibly the diode too in normal operation) and then a fuse properly rated for the current outputs involved. (ie 1.56xisc=amps rated. round up to next commercial value.) if in doubt you could lower the fuse value to trip earlier, but do not go to or lower than the total isc of the pvs. the pv input should also use connectors that can't be reversed or have a diode of rated capacity in series, but that presents a small v drop.