Abstract: A system for measuring the power or energy loss in a photovoltaic array due to soiling, which is the accumulation of dust, dirt, and/or other contaminants on the surfaces of photovoltaic modules, comprising: a pair of photovoltaic reference devices placed within or near the photovoltaic array and co-planar to the modules comprising the array, wherein one reference device is a module similar to those of the array and is allowed to accumulate soiling at the natural rate, and wherein the second reference device is a module or a cell and is periodically cleaned; and a measurement and control unit which measures and compares the electrical outputs of the soiled reference device and the clean reference device in order to determine the fraction of power lost by the soiled reference module due to soiling.

Abstract: A system for measuring the power or energy loss in a photovoltaic array due to soiling, which is the accumulation of dust, dirt, and/or other contaminants on the surfaces of photovoltaic modules, comprising: a pair of photovoltaic reference devices placed within or near the photovoltaic array and co-planar to the modules comprising the array, wherein one reference device is a module similar to those of the array and is allowed to accumulate soiling at the natural rate, and wherein the second reference device is a module or a cell and is periodically cleaned; and a measurement and control unit which measures and compares the electrical outputs of the soiled reference device and the clean reference device in order to determine the fraction of power lost by the soiled reference module due to soiling.

Abstract: An apparatus for measuring electrical characteristics of solar panels (photovoltaic modules) wherein the apparatus measures current versus voltage (“I-V”) relationships for both illuminated (“light I-V”) and/or non-illuminated (“dark I-V”) conditions; optionally provides single, dual, or four-quadrant source/sink capability; and measures one or more devices under test (DUTs). The apparatus comprises one or more source measurement units (SMUs), wherein each SMU is connected to one DUT, and optionally includes a positive high-voltage programmable power supply and/or a negative high-voltage programmable power supply. Additionally, the apparatus includes a controller which controls the functions of the SMUs, the high-voltage supplies, and other components of the apparatus, wherein the controller communicates with the SMUs over a signal bus.

Abstract: An apparatus for measuring electrical characteristics of solar panels (photovoltaic modules) wherein the apparatus measures current versus voltage (“I-V”) relationships for both illuminated (“light I-V”) and/or non-illuminated (“dark I-V”) conditions; optionally provides single, dual, or four-quadrant source/sink capability; and measures one or more devices under test (DUTs). The apparatus comprises one or more source measurement units (SMUs), wherein each SMU is connected to one DUT, and optionally includes a positive high-voltage programmable power supply and/or a negative high-voltage programmable power supply. Additionally, the apparatus includes a controller which controls the functions of the SMUs, the high-voltage supplies, and other components of the apparatus, wherein the controller communicates with the SMUs over a signal bus.

Abstract: A system for field measurement and calibration of photovoltaic reference devices, including a reference device electronics unit that measures the electrical output of a photovoltaic reference module and provides data to determine the solar irradiance received by the reference module as a function of its electrical output; and a calibrator unit that is used to routinely recalibrate the reference device electronics unit and the reference module, wherein the calibrator unit contains one or more calibrated photovoltaic reference cell(s).

Abstract: An apparatus for measuring electrical characteristics of solar panels (photovoltaic modules) wherein the apparatus measures current versus voltage (“I-V”) relationships for both illuminated (“light I-V”) and/or non-illuminated (“dark I-V”) conditions; optionally provides single, dual, or four-quadrant source/sink capability; and measures one or more devices under test (DUTs). The apparatus comprises one or more source measurement units (SMUs), wherein each SMU is connected to one DUT, and optionally includes a positive high-voltage programmable power supply and/or a negative high-voltage programmable power supply. Additionally, the apparatus includes a controller which controls the functions of the SMUs, the high-voltage supplies, and other components of the apparatus, wherein the controller communicates with the SMUs over a signal bus.

Abstract: An apparatus for performing UV light exposure testing of solar panels, also known as PV modules, with superior exposure uniformity, equipment throughput, and floor space requirements, consisting of a chamber including a plurality of UV lamps in a lamp array, at least one target plane, and reflective panels positioned within the chamber to redirect UV light to the target plane(s).

Abstract: An apparatus for exposing photovoltaic (PV) modules to simulated sunlight for testing purposes, comprising a chamber including a plurality of lamps disposed on a substantially vertical lamp plane, at least one substantially vertical target plane upon which are disposed one or more PV modules, at least one reflector for directing light from the lamps to the at least one target plane, and a cooling system to exhaust heat from the apparatus and maintain the temperature of the PV modules at a predetermined value.

Abstract: A system and methods for measuring the performance of individual strings of photovoltaic (PV) modules in a PV array, including a string combiner box with integrated capability for measurement of string current versus voltage (I-V) characteristics. The system may include calibrated solar insolation reference devices; environmental meters; and/or at least one system computer. The string combiner box allows: high precision string performance measurement during normal power generating operation; isolation of individual strings or groups of strings; and the performance of high-precision full I-V sweeps on individual strings. Methods are provided to analyze measured I-V curves to compensate for the effects of temperature and other variables thereby increasing PV module performance measurement accuracy.