30V panel for 24V battery with MPPT. Does it work?

I have a common situation where I would save some money if I used a single 30V panel (60 cell /240w) to charge a battery bank in 24V.
My concern is about the very close voltage to the required ~28V for charging the battery. Concern becomes bigger because of the high temperatures.

With an PWM it would certainly not work fine since it simply drop the voltage to the required one and this difference is too small.

But with an MPPT I understand that it could even raise the voltage for the required one (e.g. from 27V to 28V) since the MPPT always track the maximum power point and balance the current to keek the power. However, I am not sure about this.

Can the MPPT raise the voltage if needed? (Even if it is not the best efficiency range, if it works reasonably - less than 5% loss)

Can anyone help me?

Comments

  • NorthGuy
    NorthGuy Solar Expert Posts: 1,913 ✭✭
    Re: 30V panel for 24V battery with MPPT. Does it work?

    Most MPPT controllers will not be able to rise the voltage.

    Although it is possible that an MPPT controller exists that can do that.
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: 30V panel for 24V battery with MPPT. Does it work?
    NorthGuy wrote: »
    Most MPPT controllers will not be able to rise the voltage.

    Although it is possible that an MPPT controller exists that can do that.

    check out genasun.com
    disclaimer: I know nothing about them other than what I read on their website and this forum.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: 30V panel for 24V battery with MPPT. Does it work?

    Unless you use the Genasun, no--You cannot charge a 24 volt battery with a 30 Volt Vmp panel/array...

    For a 24 volt lead acid battery you need a minimum of Vmp~35 volts... The typical cost effective maximum for a PWM controller would be Vmp~40 volts (higher voltage arrays on a PWM controller is "a waste" of the higher voltage/panel power).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • rapintao
    rapintao Registered Users Posts: 2
    Re: 30V panel for 24V battery with MPPT. Does it work?

    Thank you guys for the clarifying answers!!
    I will look for a new configuration to have higher voltages!