Hello everyone,
I am currently facing an issue while attempting to incorporate multiple PV panels into a system connected to a battery. The simulation appears to work correctly when I use only one panel. However, when I increase the number of panels, the overall output decreases significantly (for example, I obtain 306 kWh annually from a single panel, but only 169 kWh from three panels combined).
I would greatly appreciate any insights or suggestions regarding the potential reasons for this discrepancy. Below, I have provided the text format of the relevant part of the simulation for reference.
Best,
!- =========== ALL OBJECTS IN CLASS: GENERATOR:PHOTOVOLTAIC ===========
Generator:Photovoltaic, PV_1, !- Name PV_1_02a57cc9, !- Surface Name PhotovoltaicPerformance:EquivalentOne-Diode, !- Photovoltaic Performance Object Type Performance1, !- Module Performance Name Decoupled, !- Heat Transfer Integration Mode 1, !- Number of Series Strings in Parallel {dimensionless} 1; !- Number of Modules in Series {dimensionless}
Generator:Photovoltaic, PV_2, !- Name PV_2_2934d52e, !- Surface Name PhotovoltaicPerformance:EquivalentOne-Diode, !- Photovoltaic Performance Object Type Performance2, !- Module Performance Name Decoupled, !- Heat Transfer Integration Mode 1, !- Number of Series Strings in Parallel {dimensionless} 1; !- Number of Modules in Series {dimensionless}
Generator:Photovoltaic, PV_3, !- Name PV_3_b5c547e8, !- Surface Name PhotovoltaicPerformance:EquivalentOne-Diode, !- Photovoltaic Performance Object Type Performance3, !- Module Performance Name Decoupled, !- Heat Transfer Integration Mode 1, !- Number of Series Strings in Parallel {dimensionless} 1; !- Number of Modules in Series {dimensionless}
!- =========== ALL OBJECTS IN CLASS: PHOTOVOLTAICPERFORMANCE:EQUIVALENTONE-DIODE ===========
PhotovoltaicPerformance:EquivalentOne-Diode, Performance1, !- Name CrystallineSilicon, !- Cell type 36, !- Number of Cells in Series {dimensionless} 2.892, !- Active Area {m2} 1, !- Transmittance Absorptance Product {dimensionless} 1.12, !- Semiconductor Bandgap {eV} 1000000, !- Shunt Resistance {ohms} 10.67, !- Short Circuit Current {A} 24.03, !- Open Circuit Voltage {V} 25, !- Reference Temperature {C} 1000, !- Reference Insolation {W/m2} 9.64, !- Module Current at Maximum Power {A} 20.75, !- Module Voltage at Maximum Power {V} 0.00512, !- Temperature Coefficient of Short Circuit Current {A/K} -.06728, !- Temperature Coefficient of Open Circuit Voltage {V/K} 20, !- Nominal Operating Cell Temperature Test Ambient Temperature {C} 45, !- Nominal Operating Cell Temperature Test Cell Temperature {C} 800, !- Nominal Operating Cell Temperature Test Insolation {W/m2} 30, !- Module Heat Loss Coefficient {W/m2-K} 50000; !- Total Heat Capacity {J/m2-K}
PhotovoltaicPerformance:EquivalentOne-Diode, Performance2, !- Name CrystallineSilicon, !- Cell type 36, !- Number of Cells in Series {dimensionless} 2.892, !- Active Area {m2} 1, !- Transmittance Absorptance Product {dimensionless} 1.12, !- Semiconductor Bandgap {eV} 1000000, !- Shunt Resistance {ohms} 10.67, !- Short Circuit Current {A} 24.03, !- Open Circuit Voltage {V} 25, !- Reference Temperature {C} 1000, !- Reference Insolation {W/m2} 9.64, !- Module Current at Maximum Power {A} 20.75, !- Module Voltage at Maximum Power {V} 0.00512, !- Temperature Coefficient of Short Circuit Current {A/K} -.06728, !- Temperature Coefficient of Open Circuit Voltage {V/K} 20, !- Nominal Operating Cell Temperature Test Ambient Temperature {C} 45, !- Nominal Operating Cell Temperature Test Cell Temperature {C} 800, !- Nominal Operating Cell Temperature Test Insolation {W/m2} 30, !- Module Heat Loss Coefficient {W/m2-K} 50000; !- Total Heat Capacity {J/m2-K}
PhotovoltaicPerformance:EquivalentOne-Diode, Performance3, !- Name CrystallineSilicon, !- Cell type 36, !- Number of Cells in Series {dimensionless} 2.892, !- Active Area {m2} 1, !- Transmittance Absorptance Product {dimensionless} 1.12, !- Semiconductor Bandgap {eV} 1000000, !- Shunt Resistance {ohms} 10.67, !- Short Circuit Current {A} 24.03, !- Open Circuit Voltage {V} 25, !- Reference Temperature {C} 1000, !- Reference Insolation {W/m2} 9.64, !- Module Current at Maximum Power {A} 20.75, !- Module Voltage at Maximum Power {V} 0.00512, !- Temperature Coefficient of Short Circuit Current {A/K} -.06728, !- Temperature Coefficient of Open Circuit Voltage {V/K} 20, !- Nominal Operating Cell Temperature Test Ambient Temperature {C} 45, !- Nominal Operating Cell Temperature Test Cell Temperature {C} 800, !- Nominal Operating Cell Temperature Test Insolation {W/m2} 30, !- Module Heat Loss Coefficient {W/m2-K} 50000; !- Total Heat Capacity {J/m2-K}
!- =========== ALL OBJECTS IN CLASS: ELECTRICLOADCENTER:GENERATORS ===========
ElectricLoadCenter:Generators, PVSys, !- Name PV_1, !- Generator 1 Name Generator:Photovoltaic, !- Generator 1 Object Type , !- Generator 1 Rated Electric Power Output {W} Always On Discrete, !- Generator 1 Availability Schedule Name , !- Generator 1 Rated Thermal to Electrical Power Ratio PV_2, !- Generator 2 Name Generator:Photovoltaic, !- Generator 2 Object Type , !- Generator 2 Rated Electric Power Output {W} Always On Discrete, !- Generator 2 Availability Schedule Name , !- Generator 2 Rated Thermal to Electrical Power Ratio PV_3, !- Generator 3 Name Generator:Photovoltaic, !- Generator 3 Object Type , !- Generator 3 Rated Electric Power Output {W} Always On Discrete; !- Generator 3 Availability Schedule Name
!- =========== ALL OBJECTS IN CLASS: ELECTRICLOADCENTER:INVERTER:SIMPLE ===========
ElectricLoadCenter:Inverter:Simple, Inverter1, !- Name Always On Discrete, !- Availability Schedule Name Room_16_9176f975, !- Zone Name , !- Radiative Fraction 0.85; !- Inverter Efficiency
!- =========== ALL OBJECTS IN CLASS: ELECTRICLOADCENTER:STORAGE:BATTERY ===========
ElectricLoadCenter:Storage:Battery, Battery1, !- Name Always On Discrete, !- Availability Schedule Name Room_16_9176f975, !- Zone Name 0, !- Radiative Fraction 10, !- Number of Battery Modules in Parallel 5, !- Number of Battery Modules in Series 850, !- Maximum Module Capacity {Ah} 0, !- Initial Fractional State of Charge 1, !- Fraction of Available Charge Capacity 0.5874, !- Change Rate from Bound Charge to Available Charge {1/hr} 12.6, !- Fully Charged Module Open Circuit Voltage {V} 12.4, !- Fully Discharged Module Open Circuit Voltage {V} BatteryChargeCurve, !- Voltage Change Curve Name for Charging BatteryDischargeCurve, !- Voltage Change Curve Name for Discharging 0.054, !- Module Internal Electrical Resistance {ohms} 100, !- Maximum Module Discharging Current {A} 10, !- Module Cut-off Voltage {V} 1, !- Module Charge Rate Limit Yes, !- Battery Life Calculation 5, !- Number of Cycle Bins BatteryCycleCurve; !- Battery Life Curve Name
!- =========== ALL OBJECTS IN CLASS: ELECTRICLOADCENTER:DISTRIBUTION ===========
ElectricLoadCenter:Distribution, DistSys1, !- Name PVSys, !- Generator List Name Baseload, !- Generator Operation Scheme Type , !- Generator Demand Limit Scheme Purchased Electric Demand Limit {W} , !- Generator Track Schedule Name Scheme Schedule Name , !- Generator Track Meter Scheme Meter Name DirectCurrentWithInverterDCStorage, !- Electrical Buss Type Inverter1, !- Inverter Name Battery1, !- Electrical Storage Object Name , !- Transformer Object Name TrackFacilityElectricDemandStoreExcessOnSite, !- Storage Operation Scheme , !- Storage Control Track Meter Name , !- Storage Converter Object Name 1, !- Maximum Storage State of Charge Fraction 0.1; !- Minimum Storage State of Charge Fraction
!- =========== ALL OBJECTS IN CLASS: ELECTRICLOADCENTER:STORAGE:CONVERTER ===========
ElectricLoadCenter:Storage:Converter, Converter1, !- Name Always On Discrete, !- Availability Schedule Name SimpleFixed, !- Power Conversion Efficiency Method 1, !- Simple Fixed Efficiency , !- Design Maximum Continuous Input Power {W} , !- Efficiency Function of Power Curve Name , !- Ancillary Power Consumed In Standby {W} Room_16_9176f975; !- Zone Name
!- =========== ALL OBJECTS IN CLASS: CURVE:RECTANGULARHYPERBOLA2 ===========
Curve:RectangularHyperbola2, BatteryChargeCurve, !- Name -0.2765, !- Coefficient1 C1 -93.27, !- Coefficient2 C2 0.0068, !- Coefficient3 C3 0, !- Minimum Value of x 1.0, !- Maximum Value of x -100, !- Minimum Curve Output 100; !- Maximum Curve Output
Curve:RectangularHyperbola2, BatteryDischargeCurve, !- Name 0.0899, !- Coefficient1 C1 -98.24, !- Coefficient2 C2 -0.0082, !- Coefficient3 C3 0, !- Minimum Value of x 1.0, !- Maximum Value of x -100, !- Minimum Curve Output 100; !- Maximum Curve Output
!- =========== ALL OBJECTS IN CLASS: CURVE:DOUBLEEXPONENTIALDECAY ===========
Curve:DoubleExponentialDecay, BatteryCycleCurve, !- Name 1380, !- Coefficient1 C1 6834, !- Coefficient2 C2 -8.75, !- Coefficient3 C3 6747, !- Coefficient4 C4 -6.22, !- Coefficient5 C5 0, !- Minimum Value of x 1.0; !- Maximum Value of x
