Solar Battery output/discharge rate

vienly
vienly Posts: 218
Name Dropper First Post First Anniversary Combo Breaker
Forumite
edited 5 May 2022 at 1:52PM in Green & ethical MoneySaving
Can someone who is familiar with Givenergy answer this question please?

If I understand correctly Givenergy Giv-Bat 5.2kwh has a discharge rate of 3kWh (51.2v x 60A = 3kWh)
If I have 2 Givenergy Giv-Bat 5.2kwh paired, would the output/discharge rate be doubled to 6kWh, or it doesn't work like that?

Reading the Givenergy spec sheet I can't seem to see it.

I've been quoted both Solaredge and Givenergy, Solaredge has a higher battery discharge rate than Givenergy.

Givenergy seems to be significantly cheaper than Solaredge but I have read positive things with Givenergy so can't quite decide yet.

Having an EV charger, and Air conditioning system at home I would assume I need the higher battery/inverter discharge rate.

Thanks

Comments

  • 94JDH
    94JDH Posts: 143
    First Anniversary First Post Name Dropper
    Forumite
    vienly said:
    Can someone who is familiar with Givenergy answer this question please?

    If I understand correctly Givenergy Giv-Bat 5.2kwh has a discharge rate of 3kWh (51.2v x 60A = 3kWh)
    If I have 2 Givenergy Giv-Bat 5.2kwh paired, would the output/discharge rate be doubled to 6kWh, or it doesn't work like that?

    Reading the Givenergy spec sheet I can't seem to see it.

    I've been quoted both Solaredge and Givenergy, Solaredge has a higher battery discharge rate than Givenergy.

    Givenergy seems to be significantly cheaper than Solaredge but I have read positive things with Givenergy so can't quite decide yet.

    Having an EV charger, and Air conditioning system at home I would assume I need the higher battery/inverter discharge rate.

    Thanks
    In my understanding it will only double the discharge rate if you have an inverter coupled to each battery.
    18 x 390W (7.02kW) East/West split over two flat roof areas at 10 degrees inclination.
  • vienly
    vienly Posts: 218
    Name Dropper First Post First Anniversary Combo Breaker
    Forumite
    94JDH said:
    vienly said:
    Can someone who is familiar with Givenergy answer this question please?

    If I understand correctly Givenergy Giv-Bat 5.2kwh has a discharge rate of 3kWh (51.2v x 60A = 3kWh)
    If I have 2 Givenergy Giv-Bat 5.2kwh paired, would the output/discharge rate be doubled to 6kWh, or it doesn't work like that?

    Reading the Givenergy spec sheet I can't seem to see it.

    I've been quoted both Solaredge and Givenergy, Solaredge has a higher battery discharge rate than Givenergy.

    Givenergy seems to be significantly cheaper than Solaredge but I have read positive things with Givenergy so can't quite decide yet.

    Having an EV charger, and Air conditioning system at home I would assume I need the higher battery/inverter discharge rate.

    Thanks
    In my understanding it will only double the discharge rate if you have an inverter coupled to each battery.

    The Giv-HY 5.0 inverter is capable of 6500W DC power, I assume it's Battery DC to Inverter DC to Consumer unit AC.
    Giv-Bat 5.2kwh is only capable of 3000W.

    Even if Giv-HY 5.0 inverter is capable of 6500W DC power, it still won't pull that much if there are 2 batterys?


  • 94JDH
    94JDH Posts: 143
    First Anniversary First Post Name Dropper
    Forumite
    vienly said:
    94JDH said:
    vienly said:
    Can someone who is familiar with Givenergy answer this question please?

    If I understand correctly Givenergy Giv-Bat 5.2kwh has a discharge rate of 3kWh (51.2v x 60A = 3kWh)
    If I have 2 Givenergy Giv-Bat 5.2kwh paired, would the output/discharge rate be doubled to 6kWh, or it doesn't work like that?

    Reading the Givenergy spec sheet I can't seem to see it.

    I've been quoted both Solaredge and Givenergy, Solaredge has a higher battery discharge rate than Givenergy.

    Givenergy seems to be significantly cheaper than Solaredge but I have read positive things with Givenergy so can't quite decide yet.

    Having an EV charger, and Air conditioning system at home I would assume I need the higher battery/inverter discharge rate.

    Thanks
    In my understanding it will only double the discharge rate if you have an inverter coupled to each battery.

    The Giv-HY 5.0 inverter is capable of 6500W DC power, I assume it's Battery DC to Inverter DC to Consumer unit AC.
    Giv-Bat 5.2kwh is only capable of 3000W.

    Even if Giv-HY 5.0 inverter is capable of 6500W DC power, it still won't pull that much if there are 2 batterys?


    If you look at the inverter it's max charge/discharge rate is 3600W - so to achieve what you're asking you will need an inverter per battery (two inverters and two batteries) to allow a total higher discharge rate. 
    If the battery is limited to a max of 3000W discharge this will then be the limiting factor. So with two inverters and two batteries ( one coupled to each) maximum theoretical discharge will be 6kW (6000W).
    18 x 390W (7.02kW) East/West split over two flat roof areas at 10 degrees inclination.
  • vienly
    vienly Posts: 218
    Name Dropper First Post First Anniversary Combo Breaker
    Forumite
    edited 5 May 2022 at 2:56PM
    probably minced my words there:
    Would the batterys run at full discharge capacity rate, so if there were 2 x Giv-Bat 5.2kwh both discharging at 3kwh to the inverter, would the Giv-HY 5.0 inverter be receiving a combined total of 5kWh from both batteries?
    If it isn't the case, bit confused to why the batteries would discharge at half the capacity if there are 2 batterys.
  • vienly
    vienly Posts: 218
    Name Dropper First Post First Anniversary Combo Breaker
    Forumite
    edited 5 May 2022 at 2:57PM
    94JDH said:
    vienly said:
    94JDH said:
    vienly said:
    Can someone who is familiar with Givenergy answer this question please?

    If I understand correctly Givenergy Giv-Bat 5.2kwh has a discharge rate of 3kWh (51.2v x 60A = 3kWh)
    If I have 2 Givenergy Giv-Bat 5.2kwh paired, would the output/discharge rate be doubled to 6kWh, or it doesn't work like that?

    Reading the Givenergy spec sheet I can't seem to see it.

    I've been quoted both Solaredge and Givenergy, Solaredge has a higher battery discharge rate than Givenergy.

    Givenergy seems to be significantly cheaper than Solaredge but I have read positive things with Givenergy so can't quite decide yet.

    Having an EV charger, and Air conditioning system at home I would assume I need the higher battery/inverter discharge rate.

    Thanks
    In my understanding it will only double the discharge rate if you have an inverter coupled to each battery.

    The Giv-HY 5.0 inverter is capable of 6500W DC power, I assume it's Battery DC to Inverter DC to Consumer unit AC.
    Giv-Bat 5.2kwh is only capable of 3000W.

    Even if Giv-HY 5.0 inverter is capable of 6500W DC power, it still won't pull that much if there are 2 batterys?


    If you look at the inverter it's max charge/discharge rate is 3600W - so to achieve what you're asking you will need an inverter per battery (two inverters and two batteries) to allow a total higher discharge rate. 
    If the battery is limited to a max of 3000W discharge this will then be the limiting factor. So with two inverters and two batteries ( one coupled to each) maximum theoretical discharge will be 6kW (6000W).

    Max DC Power  6500W (incoming from battery and solar PV) 
    The inverter it's max AC discharge rate is 5000W (Nominal AC Output Power):

    https://www.givenergy.co.uk/pdf/Version 2.0/Hybrid Inverter.pdf


  • 94JDH
    94JDH Posts: 143
    First Anniversary First Post Name Dropper
    Forumite
    vienly said:
    94JDH said:
    vienly said:
    94JDH said:
    vienly said:
    Can someone who is familiar with Givenergy answer this question please?

    If I understand correctly Givenergy Giv-Bat 5.2kwh has a discharge rate of 3kWh (51.2v x 60A = 3kWh)
    If I have 2 Givenergy Giv-Bat 5.2kwh paired, would the output/discharge rate be doubled to 6kWh, or it doesn't work like that?

    Reading the Givenergy spec sheet I can't seem to see it.

    I've been quoted both Solaredge and Givenergy, Solaredge has a higher battery discharge rate than Givenergy.

    Givenergy seems to be significantly cheaper than Solaredge but I have read positive things with Givenergy so can't quite decide yet.

    Having an EV charger, and Air conditioning system at home I would assume I need the higher battery/inverter discharge rate.

    Thanks
    In my understanding it will only double the discharge rate if you have an inverter coupled to each battery.

    The Giv-HY 5.0 inverter is capable of 6500W DC power, I assume it's Battery DC to Inverter DC to Consumer unit AC.
    Giv-Bat 5.2kwh is only capable of 3000W.

    Even if Giv-HY 5.0 inverter is capable of 6500W DC power, it still won't pull that much if there are 2 batterys?


    If you look at the inverter it's max charge/discharge rate is 3600W - so to achieve what you're asking you will need an inverter per battery (two inverters and two batteries) to allow a total higher discharge rate. 
    If the battery is limited to a max of 3000W discharge this will then be the limiting factor. So with two inverters and two batteries ( one coupled to each) maximum theoretical discharge will be 6kW (6000W).

    Max DC Power  6500W (incoming from battery and solar PV) 
    The inverter it's max AC discharge rate is 5000W (Nominal AC Output Power):

    https://www.givenergy.co.uk/pdf/Version 2.0/Hybrid Inverter.pdf


    Looking at the specification it would suggest 5000W discharge is a combination of Solar and batteries ( batteries in this case being max 2600W) - originally I thought you were looking at the gen2 version which ups the battery discharge to a max of 3600W ( battery dependent).
    Someone else might be able to confirm as my dual inverter and batteries haven't been installed yet.
    18 x 390W (7.02kW) East/West split over two flat roof areas at 10 degrees inclination.
  • ispookie666
    ispookie666 Posts: 1,176
    First Post First Anniversary Name Dropper Combo Breaker
    Forumite
    edited 8 May 2022 at 5:21PM
    I think you are confusing battery discharge and inverter capacity.

    Normally battery discharge above 1C will significantly affect capacity. 

     1C is roughly your battery capacity discharged in an hour and most manufacturers limit current to prevent disharge above 1C. This reduces customers getting disappointed due to reduced capacity and higher installation costs. 

    Adding two batteries will only provide increased capacity and not increased output, which is dependent on your inverter capacity.

    Givenergy AC coupled is limited to 3.5KWh or 3000VA continuous. hybrid inverters seems to have higher continous rating 5000VA. Might want to look into the larger inverter if you are planning to run multiple inductive loads. 


    “Don't raise your voice, improve your argument." - Desmond Tutu

    System 1 - 14 x 250W SunModule SW + Enphase ME215 microinverters (July 2015)
    System 2 - 20 x 330W Jinko Panels + Enphase IQ7+ microinverters (Jan 2022) + Givenergy AC Coupled inverter + 2 * 8.2KWh Battery (May 2022) + Mitsubishi 7.1 KW and 2* Daikin 2.5 KW A2A Heat Pump
  • Grandad2b
    Grandad2b Posts: 308
    First Anniversary Photogenic First Post Name Dropper
    Forumite
    It's complicated: the battery stores energy by a chemical reaction powered by electricity. The rate at which this reaction can run is determined by a number of factors including battery size. The battery efficiency is reduced as the rate of charge increases so at a given rate of charge charging a bigger battery will be more efficient. With LFP batteries this effect is fairly small below about 0.5C. Fast charging also causes the battery to degrade more quickly so it loses capacity and shortens its life. If you expect your inverter to put 3600W into the battery you really need at least 7.2kWh battery. 

    All this also applies for discharge - if you want to regularly draw large currents you need a bigger battery than if you're just running lighting and TV

    As @ispookie666 says you might want to look at a bigger inverter to run your bigger loads but you need to make sure the battery is up to the job too.

Meet your Ambassadors

Categories

  • All Categories
  • 341.8K Banking & Borrowing
  • 249.7K Reduce Debt & Boost Income
  • 449.2K Spending & Discounts
  • 234K Work, Benefits & Business
  • 606.2K Mortgages, Homes & Bills
  • 172.5K Life & Family
  • 246.8K Travel & Transport
  • 1.5M Hobbies & Leisure
  • 15.8K Discuss & Feedback
  • 15.1K Coronavirus Support Boards