Connecting solar PV system to main-grid

fazilcv
fazilcv Registered Users Posts: 8 ✭✭
How to connect the Solar PV system to the main grid ? inorder to get backup from main grid if solar system is insufficient to supply the needed power ad we are not using net metering. And we will use zero-injection system.

Comments

  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    There are ways to design a system to achieve what you are thinking about and there are inverter chargers which do exactly this, are your questions directed towards the design, or towards a system which is plug and play, so to speak?

    Welcome aboard by the way.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • fazilcv
    fazilcv Registered Users Posts: 8 ✭✭
    We are going to install on-grid zero injection roof top pv system and design is already done by using Helioscope. So my questions is,
    If the solar system is not producing the needed power maybe because of rain or cclooudy days etc.. can we take that additional power from main grid?,if yes how then connection should be made or additonal equipment is required for this?

    And also we are not using net metering. .
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    In order to use the PV with regular household appliences you need an inverter, with a grid supported inverter charger the grid power is input into the unit, this can configured in various ways depending on how it is setup and programed, it can be either with or without batteries. The inverter can charge batteries as well as pass through current to support loads, or support the PV if production is low, it can use battery power to support the grid or load shaving, during peak billing, using grid to recharge the batteries during off peak rates the PV will support loads in favor of grid and they are available in non grid tie versions.

    Sounds like this is something that may work for an application such as yours, a few questions, do you have an inverter and charge controller, what voltage nominal has been chosen for the inverter or are you in the development stage, more information would be helpful.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • myocardia
    myocardia Solar Expert Posts: 118 ✭✭✭
    edited October 2017 #5
    edited, misunderstood what the OP was attempting to do
    DoD= depth of discharge= amount removed from that battery   SoC= state of charge= amount remaining in that battery
    So, 0% DoD= 100% SoC, 25% DoD= 75% SoC, 50% DoD= 50% SoC, 75% DoD= 25% SoC, 100% DoD= 0% SoC
    A/C= air conditioning AC= alternating current (what comes from the outlets in your home) DC= direct current (what batteries & solar panels use)
  • Raj174
    Raj174 Solar Expert Posts: 795 ✭✭✭✭
    edited October 2017 #6
    fazilcv,
    Either an Outback or Schneider hybrid inverter would serve your purpose in this application.

    Rick
    4480W PV, MNE175DR-TR, MN Classic 150, Outback Radian GS4048A, Mate3, 51.2V 360AH nominal LiFePO4, Kohler Pro 5.2E genset.
  • bill von novak
    bill von novak Solar Expert Posts: 891 ✭✭✭✭
    fazilcv said:
    We are going to install on-grid zero injection roof top pv system and design is already done by using Helioscope. So my questions is,
    If the solar system is not producing the needed power maybe because of rain or cclooudy days etc.. can we take that additional power from main grid?,if yes how then connection should be made or additonal equipment is required for this?
    You can get a hybrid inverter with a small battery.  (The Outback line, for example.)  They support operating modes like Grid Zero that will use your own solar power preferentially over grid power.  If you draw more than the solar system can supply, it draws from the grid.  At night it draws from the battery for a short time then reverts to just the grid.

    You can do this without a battery as well.  SolarEdge has a non-battery grid tie inverter that will support zero export.  You use your own solar power.  If you don't use it all the extra solar is wasted.  If you need more than that it's pulled from the grid.
  • fazilcv
    fazilcv Registered Users Posts: 8 ✭✭
    edited October 2017 #8
    Our system is ON-GRID. And we select Hanwa Qcells solar panel model - Q Prime L G5 340Wp (180 number), Delta string inverter model -RPI  30A_120 (2 numbers) , zero injection system from green power monitor and cables & acessories from Helukable. And solar panel mounting structure is already fabricated. This is the overall details of our project.

  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    edited October 2017 #9
    After reading about the Green Power system here  http://www.greenpowermonitor.com/gpm-inyeccion-zero/ it would seem that is designed to do what you're wanting to achieve, using grid to support loads when PV output is inadequate ,as long as the following components needed, are on hand.
    Deviced needed
    To complete the setup of “Zero Injection” the following devices will be required:
    1. BMD (Basic Monitoring Device)
    2.Network Analyzer and Power DC Adaptor
    3.More solid relay and Industrial Contactor resistance state (outside the scope of GPM supply)
    4.Router 3G more digital timer (in cases where necessary)

    Is this in fact the system you have? 

     

    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • fazilcv
    fazilcv Registered Users Posts: 8 ✭✭
    The following equipment and platforms have been included in the green power system.
     GPM PV PORTAL solution
     GPM Zero Injection solution
     One (1) Basic GPM Station HW
     One (1) basic irradiance sensor
                    My question is this, using grid to support loads when PV output is inadequate - how to achieve this? . Whether we have to buy additonal components or simply to connect PV output in parallel with main grid?
                 
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    Do you have a manual, or any supporting documentation which includes wiring diagrams?
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • fazilcv
    fazilcv Registered Users Posts: 8 ✭✭
    Please the wiring diagram.
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    It would seem there are a couple of components missing, in particular a grid analyzer, a contactor to divert grid to load and perhaps some other hardware, and or software components. With limited information, including not being on site, it's extremely difficult to make suggestions with confidence, so I'm going to recommend contacting the manufacturer or their representative, as bad information is worth less than no information. 
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • fazilcv
    fazilcv Registered Users Posts: 8 ✭✭
    mcgivor  Thank you for your comments.