24 volt battery bank charging

Novaz
Novaz Solar Expert Posts: 57 ✭✭✭✭
Have not decide on the actual layout of battery bank as i am still in the read and research stage for Solar off grid
I watched a video of a guy with a 24v battery bank who ran into problems because he had no sun for 3 days and was using up his available power via the invertor https://www.youtube.com/watch?v=VnUeGqQhHIM
so anyway he ends up using a 12 volt battery charger and charging a pair of batteries for one hour at a time
man it looked painfull
so my question is as my lil quiet generator wont charge 24 volots can anyone recommend a good backup genset for my proposed 24 volt system
Thanks
Roy

Comments

  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: 24 volt battery bank charging

    What generator do you have ?? A Honda EU 2000 will pull a 30 amp 24v charger without issue and might pull a 40 amp depending on the charger.
  • CALLD
    CALLD Solar Expert Posts: 230 ✭✭
    Re: 24 volt battery bank charging

    I'm sort-of new to this whole off grid thing, but one thing I've learnt on this forum so far is its almost impossible to rely completely on the sun or the wind for all your power.

    When I first started out I believed it was simply a case of having a large enough battery bank to carry you through whatever length of bad weather you encounter, but then you end up with problems of not being able to charge it back up to 100% because your panels aren't big enough.

    You could increase the size of your panels to compensate but then if you do get a decent stretch of sunny weather you will find that your system is hugely over-sized and will end up wasting huge amounts of solar production unless you have a big hot-tub you can heat up or something equally energy-hungry you can feed with the additional power!

    At the end of the day when economics matters you have to size your system for "Average" conditions and have a backup generator or grid to get you through the bad days - something I've been getting a lot of since the started of the southern hemisphere spring!!!
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: 24 volt battery bank charging

    Your have to accept waste as part of an off grid system. As cheap as solar panels are now, living with out a generator can be done and if your peak need is in the sunnier part of the year it's not too difficult. Just spent 7 days with 2 total hours of direct sun and that late in the day. About as bad as it gets, I didn't run any back up power, but I also didn't run the water heater even turned of the 3 watt porch light! Currently my system is sized for heavy summer use so long periods when I'm drawing minimally aren't too bad... I was at about 70% SOC the morning when the sun was going to come out.

    But I did bend with the conditions. Something most people who live off grid do. I didn't do some of the 'normal things' I had been doing, running the dehydrator all day and into the night (440 watts on thermostat) and I didn't have the crock pot going or other long draws which might have been more than I was generating during much of this period. I did run my microwave some, I mostly choose not to do any cooking in the evening and limited how much I did during the day. I did let my laundry pile up, I have a load to run now that the suns back...

    You don't need to be very old to remember and have paid $5+ per watt for solar panels. I'm happy to deal with minor inconveniences to live with out a generator. It might be more of a perspective thing. The major problem is not having hot water after 3 days into the overcast. I normally travel by friends who I swap favors with, I'm currently house sitting for them, and would catch a shower here. But I have a gas hot water heater from the cabin I could install, and perhaps I will yet, but I got a silly good deal on some more panels...
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • gww1
    gww1 Solar Expert Posts: 963 ✭✭
    Re: 24 volt battery bank charging

    Whit
    Tell me about the silly good deal you got on panels. Also, it is very nice to see the sun again.
    gww
  • stmar
    stmar Solar Expert Posts: 370 ✭✭✭
    Re: 24 volt battery bank charging

    X2 Seems like every good deal I find falls through or is not what I need or the shipping to get them here is more than the product!!!!
  • Novaz
    Novaz Solar Expert Posts: 57 ✭✭✭✭
    Re: 24 volt battery bank charging

    Thanks for the replies guys I would still like some recomends on 24 volt battery chargers especially any of you using
    fork lift style battery banks which is where i am leaning to.