3.10.1.3 Collector Performance

90.1-2019

The collector performance can be characterized by the following five variables that are available from PV array manufacturers: the open-circuit voltage, the short-circuit current, the voltage and current at the maximum power-point, and the temperature coefficient of the open-circuit voltage. These are described below.

Short-Circuit Current
Applicability	All PV systems
Definition	Isc - current measured with zero voltage
Units	Amps
Input Restrictions	From manufacturer's specification
Baseline Building	None (PV not modeled for the baseline building)

Open-Circuit Voltage
Applicability	All PV systems
Definition	Voc - voltage measured with an open circuit
Units	Volts
Input Restrictions	From manufacturer's specification
Baseline Building	None (PV not modeled for the baseline building)

Maximum Power-Point Voltage and Current
Applicability	All PV systems
Definition	Imp, Vmp - current and voltage at the maximum power-point condition. These parameters are typically reported at Standard Test Conditions of 1000 W/m² and a cell temperature of 25°C.
Units	Amps and Volts
Input Restrictions	From manufacturer’s specification
Baseline Building	None (PV not modeled for the baseline building)

Open-Circuit Temperature Coefficient
Applicability	All PV systems
Definition	Temperature coefficient of the open circuit voltage (Voc) measures the changing open circuit voltage values of the PV module when the temperature increases (or decreases)
Units	%/ºC
Input Restrictions	From manufacturer's specification
Baseline Building	None (PV not modeled for the baseline building)

Short Circuit Temperature Coefficient
Applicability	All PV systems
Definition	Temperature coefficient of the short-circuit current (Isc) measures the changing short-circuit current values of the PV module when the solar cell temperature increases (or decreases)
Units	%/ºC
Input Restrictions	From manufacturer’s specification
Baseline Building	None (PV not modeled for the baseline building)

Nominal Operating Cell Temperature (NOCT)
Applicability	All PV systems
Definition	The normal operating cell temperature, typically between 45°C and 55°C
Units	Degrees Celsius (°C)
Input Restrictions	From manufacturer’s specification
Baseline Building	None (PV not modeled for the baseline building)

PV Array Mounting Type
Applicability	All PV systems
Definition	The array type describes whether the PV modules in the array are fixed, or whether they move to track the movement of the sun across the sky with one or two axes of rotation.
Units	List: Fixed, one axis tracking, two axis tracking
Input Restrictions	As designed. The default value is a fixed, or no tracking.
Baseline Building	None (PV not modeled for the baseline building)

PV Array Mounting Type
Applicability	All PV systems
Definition	The array type describes whether the PV modules in the array are fixed, or whether they move to track the movement of the sun across the sky with one or two axes of rotation
Units	List: Fixed, one axis tracking, two axis tracking
Input Restrictions	As designed. The default value is a fixed, or no tracking.
Baseline Building	None (PV not modeled for the baseline building)