An Off-Grid PV Power System for Meteorological and Eddy Covariance Flux Station in Kranji, Singapore

Abstract

This paper describes an off-grid (stand-alone) PV system for powering an eddy flux station on tropical grassland in Kranji (1°25ʹN, 103°43ʹE), Singapore. Eddy covariance flux systems are used to quantify exchanges of CO₂, H₂O and energy between the atmosphere and land. Our system includes gas analyzers for CO₂ and H₂O, and sensors for rainfall, wind speed, wind direction, long-wave and short-wave radiation, diffuse radiation, and soil heatflux. The off-grid PV system consists of eight 160W p monocrystalline solar panels, sixteen 12V deep cycle batteries, a charge controller, and an inverter. To monitor the performance of our off-grid PV system, we developed a Python program to communicate with the controller and inverter, and record data on a small single-board computer. We applied a Matlab program with meteorological measurements to predict the PV array output. The meteorological measurements and operating data of the PV system are presented and discussed here.