Guide / Help needed : 1000W hybrid/offgrid inverter + 500W load... question is...

Chan
Chan Registered Users Posts: 45 ✭✭
I am planning a setup of 220v - 1000W hybrid/offgrid inverter, with 1200W PV with 2 12v 200AH -

My question is that, my typical load is around 600W an hour during the day, does the excess production of my PV help the load or does the inverter draws the 600W from the battery... wouldn't that damage the DOD of the battery?

Assuming I want to keep powering the 600w load in the evening for 12hours... how many 12v 200ah would I need to maintain a 50DOD....

What are the benefit of using a HYBRID OFFGRID that has an AC input, since HYBRID OFFGRID are not gridtie.


Thanks

Comments

  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    edited August 2016 #2
    I am not sure what type of hybrid system you are referring to, but using round numbers just to give you a rough idea. (I will stay with watts for the moment, just for clarity)

    Load:  600 watts per hour x 12 hours = 7200 watt hours (14400 per 24 hours)

    Battery that size: 200ah x 12v = 2400 watt hours if you drain it dead. "Usable" power is half of that or less = 1200 wh per battery.

    So, if you want to draw 7200 watts from battery at a reasonable DOD: 7200 watt hours/1200 = 6 batteries of that size as a bare minimum.

    1) In reality, you would want to use fewer, larger batteries and design for a more shallow DOD. It needs to be designed properly.
    2) Your PV system is far short of handling just the daytime 7200 watt hour load, let alone recharging the batteries for night usage.

    How many watt hours were you planning to get from your 1200 watt array?
     


    I always have more questions than answers. That's the nature of life.
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Both of you have mixed up watts, watthours, and watts per hour. 

    The load is 600 watts. period.   Watts is the rate that energy is used... (the 'per hour' is built into the 'watts')

    If you multiply 600 watts by 12 hours, you get an amount of energy.  600 watts X 12 hours = 7200 watthours.

    Suppose that at noon, you are drawing energy at a rate of 600 watts.  At 1 PM you are drawing 1200 watts.  At 2 PM you are drawing 1800 watts.  At 3 PM you are drawing 2400 watts.  Your power usage is increasing at the rate of 600 watts per hour.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • Chan
    Chan Registered Users Posts: 45 ✭✭
    Lets assume I have a 12v @ 400ah.... with a load of 600W but with a SOLAR PV ARRAY OF 1200W... will the PV ARRAY AND THE HYBRID OFFGRID INVERTER be able to power the LOAD OF 600W while charging the battery during the day? So that the battery will be not be use but the INVERTER POWERING THE LOAD OF 600W...

    A hybrid inverter such as http://www.eastups.com/en/products_show_41_117.html



  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    edited August 2016 #5
    Several of the better known hybrid inverters (Outback, Schneider, SMA) can do what you want.  But even with those inverters, it can be frustrating to get all the setting just right.  I am not familiar with the inverter you linked to, so I really can't say whether it will suit you.  Have you downloaded and read the manual for it?

    --vtMaps

    edit:  perhaps you meant this link?
    http://www.eastups.com/en/products_show_48_159.html

    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • Chan
    Chan Registered Users Posts: 45 ✭✭
    any of those....

    What I was asking is that, let say I have SOLAR PANEL @ 1200W
    INVERTER THAT IS capable of delivering 1000W
    BATTERY that is 12v @ 400AH
    MORNING (DAY) HOUR LOAD OF 600W
    Will THE SOLAR PANEL since its 1200W be able to power my load (600W) during the day, without discharging my battery (dod) or cycle.
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Chan said:
    What I was asking is that, let say I have SOLAR PANEL @ 1200W
    INVERTER THAT IS capable of delivering 1000W
    BATTERY that is 12v @ 400AH
    MORNING (DAY) HOUR LOAD OF 600W
    Will THE SOLAR PANEL since its 1200W be able to power my load (600W) during the day, without discharging my battery (dod) or cycle.
    I understood what you were asking.  The hybrid one certainly ought to be able to do what you ask.  But I can't say for sure because I've never seen or heard of that hybrid inverter.  Did you read the manual?

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • Chan
    Chan Registered Users Posts: 45 ✭✭
    actually, a hybrid is almost the same as an offgrid inverter, but it already comes with typically an mppt and it can be connected to the grid to charge the battery should the pv is unable to supply it.
  • Raj174
    Raj174 Solar Expert Posts: 795 ✭✭✭✭
    I agree that this is true of this type of inverter sold in Asia, however in the US and I believe Europe a hybrid inverter is an off grid type inverter with no built in charge controller and has the capability of selling solar produced power to the grid. 
    4480W PV, MNE175DR-TR, MN Classic 150, Outback Radian GS4048A, Mate3, 51.2V 360AH nominal LiFePO4, Kohler Pro 5.2E genset.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Where do you live (nearest big city), what time do you run the loads, and what season do you plan on using the power?

    More or less, between weather, time of day, etc... You will probably not be able to run a 600 Watt load from a 1,200 Watt load in the morning without drawing down on the battery bank.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset