Need help with charge controller choice.

bill and rosa
bill and rosa Solar Expert Posts: 26
We are looking at purchasing the following solar array setup. LINK (http://www.ebay.com/itm/10-215W-2150-watts-total-New-MONO-Solar-Panel-78-w-Factory-Direct-ML-Solar-/200798501063?pt=LH_DefaultDomain_0&hash=item2ec085f8c7)

Electrical Characteristics
Maximum Power (Pmax)*: 215 W
Tolerance of Pmax: +10%/-5%
Type of Cell: Monocrystalline silicon
Cell Configuration: 91 in series
Open Circuit Voltage (Voc): 54.60 V
Maximum Power Voltage (Vpm): 44.7 V
Short Circuit Current (Isc): 5.14 A
Maximum Power Current (Ipm): 4.79 A
Module Efficiency (%): 14.4%
Maximum System (DC) Voltage: 600 V
Series Fuse Rating: 15 A
NOCT: 47.5°C
Temperature Coefficient (Pmax): -0.485%/°C
Temperature Coefficient (Voc): -0.351%/°C
Temperature Coefficient (lsc): 0.053%/°C

It outputs 600 volts 2150 watts. We are having difficulty finding a lower costing charge controller to run our 12volt system. It looks as everything is 24 volts for this type of voltage.
We found the Outback Flexmax 80 FM80 MPPT 80 AMP Solar Charge Controller 12 volt (link) http://thesolarstore.com/charge-controllers-mppt-charge-controllers-outback-flexmax-fm80-mppt-charge-controller-volt-p-77.html. but its limited to 1250 watts at 12 volts but will handle 2500 watts at 24 volts. I cant find the allowed volts in.

We are new to solar but have done extensive research on wind and solar. We are building a container home on grid to start with then off grid once we are completed. Even thought of using grid tie inverters will hooked to the grid. Any help would be great.

Comments

  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Need help with charge controller choice.

    If you have the grid available, it is,by far you best solar option in terms of kwh/$$.


    Seldome does it make much sense to eschew the grid for the notion of being "off grid". Off grid comes at twice the price and half the efficiency.

    Welcome to the forum, the are some very smart, very experienced for here who have more answers to more questions than you can imagine,, most of the time correct ones too!


    Tony
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Need help with charge controller choice.

    welcome,
    unless you have need for power outages then you won't need a controller or batteries as you'd want a grid tie inverter. at present there is only 1 controller capable of voltages that high and most here would opt to use the pvs in a series/parallel arrangement to allow lower voltages to be utilized for the battery voltages often used at 12v, 24, and 48v.

    now if you wish to have batteries and thus the need for a controller then the midnite classic lite could be an option. it can handle a bit more current, but has a buffer zone to protect for overvoltages called hyper voc. note it won't protect from 600v as it would be roughly equal to the battery voltage being used and when in overvoltage conditions there isn't any cc operations. you should note that the fm80 has about a 150v max before harm actually occurs to the cc. it may be required to be lower for operating voltages for proper functionality. you will not have all of the pvs in series or bye bye controller. 3 in series would have the voc over the 150v destructive max of the cc by 13.8v.

    as you noted, the higher the battery voltage, the more wattage from pvs that can be handled. staying at 12v for a large pv array would necessitate more controllers if over the max ability of the controller in question.

    as i mentioned i'd use the grid with a gt inverter. there are some that can do both if you insist on going off grid later and could save you some $ on another inverter. these are battery backed gt inverters and aren't as efficient as straight grid tied inverters.
  • bill and rosa
    bill and rosa Solar Expert Posts: 26
    Re: Need help with charge controller choice.

    Thank you for the warm welcoming.
    So i reality to use such a large solar array, I would need to take half of the array and use it direct to a grid tie and the other half for my off grid system. Then my 12 volt system would have a easier selection on charge controllers. I will eventually be off the grid. But want the ability to have standby power for power outages and such. We are also installing a wind turbine for extra free energy. If I had a creek or river on the land I would also use water turbine.
    Here is another twist. Would it be more efficient to move up to 24volts since the inverter I listed in my opening question could handle the wattage and if I understand it correctly 24 volt systems require less amp hours over 12 volt systems.
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: Need help with charge controller choice.

    Gosh, I think you should do more research before you buy anything! You have stated several things, that appear confusing "It outputs 600 volts 2150 watts." "extra free energy" Do you have an existing 12 volt system?

    Your balance of system, mounting, wiring, charge controller, inverter will in total cost more than this array.

    You can do a hybrid system but if you know you want to do off grid that's one thing and grid connect is another.

    Why not price different systems, grid connect and off grid, use the the NAWS web site, then figure out total costs and expected return, in usable wattage or $$$ return.
    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.
  • bill and rosa
    bill and rosa Solar Expert Posts: 26
    Re: Need help with charge controller choice.

    Sorry Photowhit. But i dont think you read my first posting. I have 2 test systems. I built the solar panels myself and used smaller inverters both grid tied and off grid. We are now planning our new home Recycling shipping containers and putting a full solar and wind system in. We will be tied to the grid while building the house. and while attached would like to run grid tied. BUT will build a OFF- GRID system for the future and backup for the grid system(day time system). With the 2150 watt system and what we plan on having in our home that uses electricity we will use less than 50% of the power created. Why not send it back to the grid for a easy paycheck. I just was asking about the charge controller(s) that could handle the MAX 600 volts that was a low cost. The ones I found that could were all 1200 and up. the one I posted link to was less than 600 but had to run 24 volts to handle the 2150 watts. But thanks for your input.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Need help with charge controller choice.

    definitely do not buy anything as you are somewhat lost with this. we don't want you to buy the wrong things. before we go further please tell us of the loads you wish backed up, terms in wattage and the time frame of use per day (in either watt hours or kilowatt hours). now in the future if you are definitely going off grid then all things will need powered by the inverter and batteries.
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: Need help with charge controller choice.

    Still not making sense to me, you may know more about it than I. You speak of 600 volts and then running at 24 volt...

    What is 'It' in this statement, "It outputs 600 volts 2150 watts"

    I thought hybrid systems work at charging voltages for a battery bank, if it was a 48 volt battery bank it would work in the range of a MPPT CC for a 48v battery bank 70-120volts not the high voltages of grid tie only systems...

    I can speak to off grid systems and typically you waste close to 75% of the energy generated...
    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.