24v or 12v Solar Panel

Broq
Broq Registered Users Posts: 2
Hi, I'm in the market for a solar panel and want to know if there are any benefits using a 24v panel over 12v panel to charge my 12v LiFePO4
battery besides the fact 24v panels are cheaper here in Australia
I have a 30amp MPPT controller accepts both 24v and 12v.
I have read the higher voltage will be converted to amps through the MPPT controller.
As mentioned because they are cheaper i was wanting to know if this is the way to go?

Comments

  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Yes, cheaper per watt is the way to go, so long as you have a true MPPT type charge controller. Be aware of the charge controllers specs.

    The charge controller will manage the power (wattage) and output the best possible for the battery range/charging.
    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.
  • Broq
    Broq Registered Users Posts: 2
    edited January 2021 #3
  • MichaelK
    MichaelK Registered Users Posts: 234 ✭✭✭
    Amusingly, one way to spot the fakes is shipping weight.  A MPPT controller that has a shipping weight of only 250 grams is a fake PMW unit.  Your product weights 1500g, so that is an indicator for me that might be real.

    The reality is that the large toroid rings of copper, and the big capacitors on the circuit board of a real MPPT unit add a lot of weight to the unit.

    The fake units are marketed from overseas sellers that are counting on cheap shipping to deliver their fake product, and added weight to it reduces their scam profit.

    In any case, remember to always connect the battery terminals to the unit first, let it boot up, then connect the solar.  Do you have any capacity to measure amperage?  With a DC clamp meter, you could measure the amps flowing from the panel to the controller, and then the amps from the controller to the battery.  If for example the amperage from the panel is 6.2A, and the amperage at the battery is 11.1A, then you've got a real product.
    System 1) 15 Renogy 300w + 4 250W Astronergy panels,  Midnight 200 CC, 8 Trojan L16 bat., Schneider XW6848 NA inverter, AC-Delco 6000w gen.
    System 2) 8 YingLi 250W panels, Midnight 200CC, three 8V Rolls batteries, Schneider Conext 4024 inverter (workshop)