Need help with batteries

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Comments

  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,728 ✭✭✭✭✭✭
    They are from Victron and a very good company. If you can get them and actually have someone who will warranty them locally you should get one. They will allow you to use just about any combination of solar panels. If they made an non MPPT controller I would also compare as it might give you better options in a small system. Good Luck
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Victron is a good European company--From what I have seen (I am not in the business).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Victron is a big supplier in Holland to the boating crowd...  good stuff,  

    Is that available out in- the- jungle?

    Looks like , if you want to bluetooth your data the 85 is the better choice, no dongle needed, but best check to see if a proprietary program od ?? is needed to get at it...

     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • South Africa
    South Africa Solar Expert Posts: 295 ✭✭✭
    InTheJungle with Victron, you did not go wrong. Go with the Victorn MPPT 150/85 if you can. Expensive, but more room to maneuver if you want to add more panels later or in the future.

    Also get the VEDirect to USB cable with the Controller, and the MK2 USB cable for the inverter that you can read / interface / alter / program both the controller and the inverter.

    Also get a BMV702 with temp sensor. To see what goes on in the batteries and the temp sensor to tell you the actual battery temperature to see if you can compensate.

    Batteries: It you can get 6v Trojan T105RE's 225ah batteries, it would be better. The Naradas are UPS batteries, not ideal for solar unless you never take them below 20% DOD, and that is tricky.

    You most probably have a 1600VA 24w Victron Multiplus (?) so it is ideal for power failures. If there are utilities, inverter will use that to re-charge the batteries, If there are no utilities, it will use batteries / solar. So after an outage and no solar power, the batteries will be re-charged using utilities.

    Daytime if there are power failures, the panels will power your load.

    You have very good equipment there. They are designed for extreme locations.
    5kVA Victron Multiplus II, 5.2kW array, 14kWh DIYLifepo4 bank, all grid-tied.


  • inthejungle
    inthejungle Solar Expert Posts: 91 ✭✭
    I have a Victron Inverter, they should work together well.
    In Niger, trying to keep a LG FMA 102NAMA fridge(This has the inverter compressor) backed up with solar using a Victron Multi-Plus Inverter/Charger Compact 12v 1600w with a 70a charger built in.I want to back it up for 4-8 hours. I am also running a few O2 cool fans and a few Thin Lite LED's of my batteries for when the grid is down so my kids can sleep.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    I've heard of blue sea and blue sky
    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 ,

  • inthejungle
    inthejungle Solar Expert Posts: 91 ✭✭
    Thank you for everyone's thoughts, south africa, I was thinking about getting those cables and BMV. I really liked the BMV in the past, at present I am going to wait for someone from a neighboring country to bring me some Rolls s550, a little patience should pay off!

    can anyone help me with the math on the solar panels and the rate of  charge back into the batteries. If I get 3 230w panels, so 3*230=690w. I am in the Sahara so 5 hours of sun=3,450 w a day.

    I don't want to end up with a battery that is getting discharged, no grid for the multi plus inverter/charger to charge and not enough panels to charge the batteries.

    Thoughts on my numbers?
    In Niger, trying to keep a LG FMA 102NAMA fridge(This has the inverter compressor) backed up with solar using a Victron Multi-Plus Inverter/Charger Compact 12v 1600w with a 70a charger built in.I want to back it up for 4-8 hours. I am also running a few O2 cool fans and a few Thin Lite LED's of my batteries for when the grid is down so my kids can sleep.
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,728 ✭✭✭✭✭✭
    Make sure the batteries all have the same lot and date code before you pay or insist on it before! Tell them that you will test the batteries with a voltmeter to make sure they all are the same. I would buy a hydrometer so that you can test SG before you buy.
    Buyer beware is more important than ever in your situation!

    You are missing something in your math! Loss and the fact the panels are not as much as you think.  The good news is that you have grid power most of the time to charge and you can always use a generator. I think you will be fine but do get some help with the math so you understand! Good Luck to you!
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    edited October 2016 #40
    How many batteries do you plan on getting?

    Just to run some numbers... For Niger, hours of sun per day:
    http://www.solarelectricityhandbook.com/solar-irradiance.html

    Niamey
    Average Solar Insolation figures

    Measured in kWh/m2/day onto a solar panel set at a 76° angle from vertical:
    (For best year-round performance)
    Jan Feb Mar Apr May Jun
    6.61
     
    7.14
     
    6.86
     
    6.31
     
    6.63
     
    6.47
     
    Jul Aug Sep Oct Nov Dec
    5.83
     
    5.01
     
    5.71
     
    6.48
     
    6.85
     
    6.49
     
    For an off grid system:
    • 3 * 230 Watt panels * 0.52 off grid system eff * 5.01 hours of sun per day (August long term average) = 1,798 WH per day (August break even month)
    And, yes, the 52% system efficiency (solar panels in to AC power out) is right.

    For charging, your planned panels would support:
    • 3 * 230 Watt panels * 0.77 panel+controller derating * 1/14.5 volts charging * 1/0.05 rate of charge minimum = 489 AH @ 12 volt battery maximum (emergency power, weekend usage, seasonal usage)
    • 3 * 230 Watt panels * 0.77 panel+controller derating * 1/14.5 volts charging * 1/0.10 rate of charge minimum = 244 AH @ 12 volt nominal (full time off
    • 3 * 230 Watt panels * 0.77 panel+controller derating * 1/14.5 volts charging * 1/0.13 rate of charge minimum = 188 AH @ 12 volt minimum "cost effective" battery bank
    For a 1,600 Watt AC inverter, I would suggest a minimum of 640 AH @ 12 volts to support maximum inverter rating and surge current (400 AH per 1,000 watts, @ 12 volt battery bank).

    The Rolls s550 batteries are 428 AH @ 6 volts--So, if you were running solely from solar array, a pair of them would be the maximum I would suggest for a 230 Watt array. And they will support a 1,280 Watt AC output (maximum continuous) from the two batteries.

    Since you have AC mains (at least most of the time), you really do not need any solar panels--The size of the solar array is really your choice--For 2x s550 batteries, 3-6 of those 230 Watt panels are certainly justifiable--As is simply using the AC mains for charging through your Victron inverter-charger. At 70 Amps., it would support up to 4x s550 batteries OK (70 amps charging / 2*428 AH @ 12 volt battery bank = 0.082) 8.2% rate of charge. (5% rate of charge minimum, 10% rate of charge is usually recommended for deep cycle flooded cell batteries).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Another 'adjustment factor' that you might read in the CC literature is: you need 110% to 130% of the ampHrs used to fully charge your batteries.... so if you use 100Ahr you need 130 to recharge fully...

    hth
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • inthejungle
    inthejungle Solar Expert Posts: 91 ✭✭
    BB, westbranch and others what if I didn't get the 3 panels and got another set of batteries? That would give me roughly 850AH. My only concern is that if AC mains went down for 24-48 hours I should be fine, but then when the AC comes back how long is it going to take to get the batteries back to full.


    In Niger, trying to keep a LG FMA 102NAMA fridge(This has the inverter compressor) backed up with solar using a Victron Multi-Plus Inverter/Charger Compact 12v 1600w with a 70a charger built in.I want to back it up for 4-8 hours. I am also running a few O2 cool fans and a few Thin Lite LED's of my batteries for when the grid is down so my kids can sleep.
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    from your sig.:  70 A per hr from the charger
    so take the fridge and other loads X hrs  divide by 70 = hrs needed  X 1.3 = time the grid has to be active to recharge.

    Assume you have to drain your batteries (50% max DoD) = 425Ahr / 70 = ~ 8 hrs... + ??? (not counting any solar incoming)

    remember that as the battery gets more charged, the Amps going in tails off starting at about 85 - 90% SoC, down to whatever you have set for the Float Charge Voltage.
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,728 ✭✭✭✭✭✭
    edited October 2016 #44
    You are overthinking the 2 sets of batteries. As Bill said you really do not need solar panels.
    However, if you think you will loose power for 2 days a small array would keep you going until the grid comes back up.
    Then again having the extra batteries might be good if they are hard for you to get. Most of us here just have to have the money,
    the problems you have are far more difficult,  Good Luck!
    Time for you to make a decision!
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • South Africa
    South Africa Solar Expert Posts: 295 ✭✭✭
    Inthejungle I would go for more batteries first. 70amps charger = 700ah battery bank at 10% rate of charge.

    You could go bigger bank that is charged at a 5% rate of charge, if you have infrequent power failures.

    When the grid power becomes really erratic, only then would I invest in panels to keep the batteries charged. Charging from solar should then ideally be 10% rate of charge, which means a rather large array then, but then batteries are the expensive part.
    5kVA Victron Multiplus II, 5.2kW array, 14kWh DIYLifepo4 bank, all grid-tied.