Solar power bank to power trickle charger

Discussion in 'The Garage' started by Stroked 550, May 2, 2020.

  1. Stroked 550

    Stroked 550 Dirt Nut

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    Hey guys

    I am looking to buy a solar power bank to run a noco trickle charger https://no.co/gen1 to keep my batteries maintained

    What solar power bank do I need to meet the demand ?
    #1
  2. HeavyMetal

    HeavyMetal Been here awhile

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    Why not just use a solar power battery maintainer?
    I can't understand charging a battery bank to convert to ac for the charger to convert back to dc to charge a battery. :dunno
    #2
  3. broncobowsher

    broncobowsher Long timer

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    You are doing it wrong. Solar to a charge controller, which is the battery maintainer. My favorite charge controller for small loads is a SunKeeper SK6. They actually publish the dark current draw (what it draws at night) and it is very good. Most others won't publish that number or it they do it is a lot higher. The SK6 will handle up to a 100W panel which is HUGE for just a maintainer. Even a little 25W panel is plenty for most applications.

    Guess I should ask, what are you trying to maintain? Just a motorcycle battery while parked in a shed? Small panel is fine. Back up battery for a 2 megawatt diesel genset, might go a little closer to that 100w size.

    For reference, the 70W panel I run will maintain a battery while running a portable refrigerator.
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  4. Stroked 550

    Stroked 550 Dirt Nut

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    thanks for educating me on this I appreciate it.... thats awesome that they provide all the specs and that it draws at night pretty well.

    Im maintaining the diesel RV that has 4 batteries
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  5. Stroked 550

    Stroked 550 Dirt Nut

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    would a 30 watt setup be enough to maintain my rig?
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  6. Coma

    Coma Long timer Supporter

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    I had a Monaco Dynasty that came with a 90W panels and charge controller that maintained 4 6V deep cycle and an 8D start battery. On a full sunny day it would almost keep topped off with no draw beside parasite.

    When the original panel corroded internally I replaced it with two 100W panels from https://amsolar.com/rv-solar-panels-complete-kits

    Two panels kept everything topped off even running a 17cu residential refrigerator. If you really want to boondocks get 400W or more.
    #6
  7. Coma

    Coma Long timer Supporter

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    Depends on your parasitic draw. Is that to include start batteries and house? Do you have a separate generator battery?
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  8. Salsa

    Salsa Long timer

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    I "Maintain" my Dodge van in Alaska for 10 months by disconnect the battery.

    Nothing else, no solar ,no nothing.

    Don
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  9. Johann

    Johann Commuterous Tankslapperous

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    Edit: 30W should work under right conditions see post below with figures.

    If you need enough solar to maintain the panels plus provide enough charge to replace what is lost in running stuff (fridge, water pumps, lights, TVs etc) the first thing to do is a power audit of all the stuff being powered in any 24hr period, you can then work backwards and calculate how many Amp hours are being taken from the batteries every day. Once you know that figure you can work out how many solar panels you will need. Depends entirely on your consumption, if you live like Fred Flinstone 100W might be enough, if you are a heavy user could be three of four times that.
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  10. Johann

    Johann Commuterous Tankslapperous

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    That works, natural discharge rates for batteries can be very low. Cold temps help. I think most FLAs are somewhere around 4-6% per month but AGMs can be a lot lower. The advantage of solar is that it keeps the batteries permanently on float which is the kindest thing you can do a battery. The difference in longevity of even cheapo batteries being charged by solar and being charged by gennies or engine alternators is quite surprising, the solar charged batteries will last a lot longer, Pre-solar it was a given that a heavily abused battery (as most liveaboard batteries are) would last about two years, any more was a bonus. Post solar it was more and more common to hear of batteries lasting four, five years or more of continuous use.
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  11. Stroked 550

    Stroked 550 Dirt Nut

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    when you have 4 of them with leads running all over the place its a little more of a PITA and I use it off and on lol
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  12. Salsa

    Salsa Long timer

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    You probably have or could put battery switches on most of them.

    Don
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  13. Johann

    Johann Commuterous Tankslapperous

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    Thinking more about this 30W would do the job OK if it was just maintaining the batteries and the batteries were isolated based on 100Ah FLA batteries. If a flooded lead acid battery loses 5% a month a 100Ah battery will be at 95Ah after a month, for one battery the panel only has to make up that shortfall. That´s 5/30=0.16Ah a day or 0.64Ah for four batteries.
    #13
  14. broncobowsher

    broncobowsher Long timer

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    30W should be more than enough. I have a 70W and that is enough to maintain a battery AND run a 12v refrigerator.
    #14
  15. Arbolmano

    Arbolmano Not so Studly

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    I’m partial to the cheap solar maintainers at Harbor Freight. For just maintaining. EZ install can run multiples.
    Wait for sale coupon.
    #15
  16. Gruesome

    Gruesome Alter Heizer

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    #16