Solar Measurement System Research Articles

IoT Application for Real-Time Monitoring of Solar Home Systems Based on Arduino™ With 3G Connectivity

A novel datalogger based on free software and hardware has been designed, built, programmed, and installed as an experimental prototype in multiple sites. Remote monitoring extends the effectiveness of the datalogger in the areas deprived of electrical grid and traditional wired telecommunication networks. The integration of Internet of Things in solar measurement systems allows the remote monitoring of small stand-alone photovoltaic (PV) systems, enhancing the performance and the maintenance of the system. The datalogger measures electric and climatic parameters (up to 14 parameters, expandable) with the required accuracy established by the IEC61724 standard; to include 3G technology in it allowed the stand-alone PV systems system monitoring remotely via web or via mobile application, all at low cost. An outdoor campaign of over 12 months under the harsh environmental conditions at multiple locations was performed to test the new datalogger under real and different conditions demonstrating the robustness and the reliability of the system.

Calibration and postlaunch performance of the Meteor 3/TOMS instrument

Prelaunch and postlaunch calibration results for the Meteor 3/TOMS instrument are presented here. The instrument, launched aboard a Russian spacecraft in 1991, is the second in a series of total ozone mapping spectrometer (TOMS) instruments designed to provide daily global mapping of ozone overburden. Ozone amounts are retrieved from measurements of Earth albedo in the 312‐ to 380‐nm range. The accuracy of albedo measurements is primarily tied to knowledge of the reflective properties of diffusers used in the calibrations and to the instrument's wavelength selection. These and other important prelaunch calibrations are presented. Their estimated accuracies are within the bounds necessary to determine column ozone to better than 1%. However, postlaunch validation results indicate some prelaunch calibration uncertainties may be larger than originally estimated. Instrument calibrations have been maintained postlaunch to within a corresponding 1% error in retrieved ozone. Onboard calibrations, including wavelength monitoring and a three‐diffuser solar measurement system, are described and specific results are presented. Other issues, such as the effects of orbital precession on calibration and recent chopper wheel malfunctions, are also discussed.