400a/h of LiFePO4 and 560w of solar…

Bunkysdad
Bunkysdad Registered Users Posts: 38 ✭✭
in Caravan, Recreational Vehicle, and Marine Power Systems #1
At present I have in my truck camper one 200a/h LFP and 440w of solar, but I’m in the process of adding another 120w panel (so almost out of roof real estate - lol), and thinking about adding another 200a/h in a parallel configuration…

We occasionally run the 11kbtu air conditioner (with soft start) from the single LFP when off-grid camping as well as the microwave and Keurig coffee maker, so we are relatively moderate to heavy energy users depending on the season…In the summer heat we can run the air continuous without much difficulty for about 2.5 hrs (compressor cycling, concurrent with 440w solar - and if necessary, I have a Honda 2200)…

Just wondering if I go with a second 200a/h LFP, and the two batteries charge simultaneously, and considering LFP’s relatively rapid charge recovery rate (particularly during peak harvest hours) what to expect with having 560w of solar charging with 400a/h total LFP capacity??

Any informed input is much appreciated :)

Bunkysdad
· Share on Twitter

Comments

  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    #2
    500W @ 14V = about 35A of charging.   say there are 1.5 peak hours and 1.5 off-peak.   is 90ah going to supply your daily loads, or will you need to run the vehicle engine for a while to top off the battery ?

    ( assuming you have a efficient MPPT charge controller and your roof top panels are in full sun)
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

    · Share on Twitter
  • Bunkysdad
    Bunkysdad Registered Users Posts: 38 ✭✭
    #3
    Yes on the MPPT and assuming 35a in ‘ideal conditions’, but due to the vagaries of solar, I’m assuming a more conservative 25a per hr, or say 75a/hr over a 3 hour period, this since we mostly camp off-grid in the Nevada desert…As of yet, I haven’t had a solid need to charge from the vehicle, so haven’t bothered to install a dc-to-dc converter…Hypothetically, were I to run the air conditioner at say 95 dc amps (compressor cycling, concurrent with solar), I could imagine a 3-4 hr run time and still have a fair reserve that’ll extend till the next peak solar harvest period…JMO
    · Share on Twitter

Categories