Field Trial of Meteorological Station Using PV Reference Cells

We report on a field trial of a new meteorological station concept for resource assessment at the site of a prospective utility-scale photovoltaic (PV) power plant to be developed by 7X Energy. Cost savings are achieved by substituting Atonometrics PV reference cells for thermopile pyranometers in a unique multi-reference-cell array configuration that allows accurate determination of global horizontal irradiance (GHI) and by using advanced remote diagnostics to minimize the need for on-site visits for sensor cleaning. Reference data are also obtained from a second station at the site employing thermopile pyranometers and maintained through weekly site visits for pyranometer cleaning. Data from both stations are compared to industry-leading SolarAnywhere®satellite-derived irradiance measurements from Clean Power Research and are used for tuning of the satellite model for long-term irradiance prediction and site resource assessment. Results comparing the new station concept employing PV reference cells versus the traditional one based on thermopile pyranometers showed that both compared equivalently with the satellite data and tuning model within instrument uncertainties, although small bias differences require more investigation.