A comparison of irradiance measurements using low-cost sensors to high-quality sensors

Abstract

Solar photovoltaic technology is one of the most interesting options for future energy sources. It has high technical and sustainable potential due to its capability to produce electricity without fossil fuels and with small maintenance expenses. The technology has small environmental impacts and it could be one solution for global energy demand. Photovoltaic cells have been used to provide energy for satellites since the 1950s due to their capability to transform solar radiation straight to electricity. The photovoltaic technology investment has increased due to diffusion policies across the globe. Over 100 countries are using photovoltaics. The objective of the thesis was to use the Quantitative approach to compare low-cost sensors with high-cost sensors via statistical analysis and give suggestions on how to upgrade a low-cost sensor prototype. The low-cost sensor was a polycrystalline solar cell and two high-cost sensors were a silicon photodiode pyranometer and a thermopile pyranometer. In addition, the interest was to analyse the impact of seasonal variations and temperature changes on measurement values. The study showed that solar cells and pyranometers have a strong relationship. Seasonal variations and temperature changes had an impact on the measurement values. Results showed that the solar cell is temperature dependent. The low-cost sensors calibration process could be upgraded by concerning the cloudiness of the sky. Longer measurement periods would increase the reliability of the process.