Photovoltaic (Equivalent One Diode)
Photovoltaic generators, also known as solar panels, collect the suns energy and convert it into electricity.
This model describes the performance characteristics of Photovoltaic (PV) modules to be modeled using an equivalent one-diode circuit. This model is also known at the 4- or 5-parameter TRNSYS model for photovoltaics. The Photovoltaic information found in the Energy Plus Input Output Reference Manual shows several sample PV array types with their input values. The fields for this library member can be found below.
Cell Type
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Default Value: Crystalline Silicon
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Typical Range: N/A
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Min & Max: N/A
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Units: Crystalline Silicon, Amorphous Silicon
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This field is used to describe the type of technology used in the PV module. There are two options available, Crystalline Silicon and Amorphous Silicon. The choice affects the methodology used to calculate electricity generation.
Number of Cells in Series
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Default Value: 1
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Typical Range: 1 to 999 x 1012
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Min & Max: N/A
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Units: Integer
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This field is an integer representing the number of individual cells wired in series to make up a single module. The typical number for a 12V crystalline silicon PV module is 36.
Active Area
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Default Value: 108 ft2 [IP], 0.63 m2 [SI]
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Typical Range: 1 to 999 x 1012
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Min & Max: N/A
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Units: ft2, cm2, in2, m2, mm2
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This field is the total active area of the PV module.
Absorptance Transmittance
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Default Value: 0.9
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Typical Range: -999 x 1012 to 999 x 1012
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Min & Max: N/A
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Units: N/A
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This field indicates the transmittance-absorptance product at normal incidence angles for the PV modules. If the transmittance-absorptance product is positive, that value will be used for all angles of incidence. If the value specified is negative, then the magnitude of the given value will be used for normal incidence and the IAM modifier correlation will be used for all other angles.
Semiconductor Bandgap
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Default Value: 1.12 eV
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Typical Range: 1 to 999 x 1012
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Min & Max: N/A
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Units: eV (electron volts)
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This field is the semiconductor bandgap for the PV material. The bandgap for silicon is 1.12 eV.
PV Electrical Characteristics
Shunt Resistance
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Default Value: 1,000,000 ohms
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Typical Range: 0 to 999 x 1012
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Min & Max: N/A
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Units: ohms
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This field is the shunt (parallel resistance in the single diode electrical model of the PV. The shunt resistance is effectively infinite for crystalline silicon based PV modules and is finite for thin film and exotic metal modules.
Short Circuit Current
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Default Value: 4.75 Amps
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Typical Range: 0 to 999 x 1012
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Min & Max: N/A
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Units: Amps
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This field is the short circuit current (in Amps) for an individual module in the PV array at reference conditions.
Open Circuit Voltage
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Default Value: 21.4 Volts
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Typical Range: 0 to 999 x 1012
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Min & Max: N/A
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Units: Volts
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This field is the open circuit voltage (in volts) for an individual module in the PV array at reference conditions.
Reference Temperature
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Default Value: 77
 F [IP], 25°C [SI] |
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Typical Range: 0 to 999 x 1012
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Min & Max: N/A
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Units: °F, °C [SI]
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This field is the ambient temperature (in °F) at reference conditions.
Reference Radiation Level
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Default Value: 1000 W/m2
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Typical Range: 0 to 999 x 1012
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Min & Max: N/A
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Units: W/m2
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This field is the radiation level (in W/m2) at reference conditions. Also known as Reference Insolation.
Module Current at Maximum Power
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Default Value: 4.45 Amps
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Typical Range: 0 to 999 x 1012
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Min & Max: N/A
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Units: Amps
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This input is module current at the maximum power point and reference conditions.
Module Voltage at Maximum Power
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Default Value: 17 Volts
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Typical Range: 0 to 999 x 1012
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Min & Max: N/A
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Units: Volts
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This input is module voltage at the maximum power point and reference conditions.
Cell Temperature
Cell Ambient Temperature
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Default Value: 68°F [IP], 20°C [SI]
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Typical Range: 0 to 999 x 1012
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Min & Max: N/A
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Units: °F, °C [SI]
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This input represents the ambient temperature from the nominal operating cell temperature (NOCT) test.
Cell Test Cell Temperature
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Default Value: 117°F [IP], 47°C [SI]
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Typical Range: 0 to 999 x 1012
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Min & Max: N/A
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Units: °F, °C [SI]
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This input represents the cell temperature from the nominal operating cell temperature (NOCT) test.
Cell Test Insolation
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Default Value: 800 W/m2
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Typical Range: 0 to 999 x 1012
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Min & Max: N/A
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Units: W/m2
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This input represents the insolation level from the nominal operating cell temperature (NOCT) test.
Temperature Coefficients
Short Circuit Current Coefficient
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Default Value: 0.00065 A/°K
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Typical Range: 0 to 999 x 1012
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Min & Max: N/A
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Units: A/°K
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This field accounts for the fact that the module short circuit current is temperature dependent. The coefficient is given in Amps/Kelvin.
Open Circuit Voltage Coefficient
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Default Value: - 0.08 V/°K
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Typical Range: -999 x 1012 to 999 x 1012
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Min & Max: N/A
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Units: V/°K
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This field accounts for the fact that the module open circuit voltage is temperature dependent. The coefficient is given in Volts/Kelvin.