cooling strategies

jonr
jonr Solar Expert Posts: 1,386 ✭✭✭✭
So keeping batteries cool makes a significant difference in lifetime and costs.   What do people do for this?  Just ventilate well?  Smart ventilation that compares battery temp to outdoor temp?  Opportunistic refrigeration?  How about protecting the top of the batteries and then using a water mist (energy efficient evaporative cooling)?  Perhaps combine this with some ground water cooling around the bases.

I am available for custom hardware/firmware development

Comments

  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭

    Hi jonr,

    For new construction,  if one can create a Root Cellar,  basement,  or similar,  which still has adequate access that batteries can be installer and removed,  this seems the most efficient.

    Personally use priority A/C in the Power Room for the benefit of batteries and electronics.  It works well,  but,  of course, it is a large hit to overall efficiency.

    Would avoid introducing humidity into the environment,  however,  if the batteries were in a separate room from the electronics,  perhaps toying with evaporation for battery cooling might be interesting.

    Need to add more PVs here,  to handle more A/C for the living spaces,  or perhaps Evap cooling,  as the Summer humidity is generally low.

    FWIW,   Vic

    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    I see tremendous successes with the root cellar type approach. But batteries in the crawl space under homes and inside the conditioned space can work well. A few customers in North Texas, Oklahoma and Kansas have combined a tornado shelter and their battery bunker.

    I like the underground applications best because of the inherent efficiency. We have around 260 remote, unattended PV systems that have "buried or semi-buried" battery banks. Sizes are 7-50 KWH and some are pushing 11.5 years of operation in higher elevation/colder areas. Without fail, the cooler battery banks last much longer than the others with all else being equal.

    Keep in mind that I only deal with AGM's nowadays, so ventilation requirements are fractional as compared to flooded battery designs.

    I always have more questions than answers. That's the nature of life.
  • jonr
    jonr Solar Expert Posts: 1,386 ✭✭✭✭
    Also, I understand  < 1/2 of the heat production.   So a much smaller ground contact area should suffice.   

    I am available for custom hardware/firmware development

  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    edited August 2016 #5
    Most of the systems that I get involved with have the batteries racked up on shelves - two to six shelves high. With the batteries mounted on their short side, it is easy to check individual voltages, keep an eye on connections and use very little floor space.

    For example, an L16 sitting on its short side is about 7" wide. Allowing for some air space between batteries, you can put a row of eight on a shelf that is about 5 feet wide. So, even a large 57 KWH bank with (24) 2v L16's, only uses a floor space of about 18" x 72" . 

    That's why I really like the root cellar approach. :)
    I always have more questions than answers. That's the nature of life.
  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    edited August 2016 #6
    This goes back a few years (7?) but it is a typical layout that I see from my customers (Cover removed in this picture)
    http://marckurth.com/48vrack.jpg
    I always have more questions than answers. That's the nature of life.