Solar irradiances measured using SPN1 radiometers: uncertainties and clues for development
- 1Laboratoire de Météorologie Dynamique, Palaiseau, France
- 2Peak Design, Winster, UK
- 3MINES ParisTech, PSL Research University, O.I.E. – Centre Observation, Impacts, Energie, CS 10207 rue Claude Daunesse 06904 Sophia Antipolis Cedex, France
- 4Pacific Northwest National Laboratory, Richland, WA, USA
- 5Meteoswiss, Payerne, Switzerland
- 6EDF R&D-CEREA, Chatou, France
- 7Institut Pierre Simon Laplace (IPSL), Palaiseau, France
Abstract. The fast development of solar radiation and energy applications, such as photovoltaic and solar thermodynamic systems, has increased the need for solar radiation measurement and monitoring, for not only the global but also the diffuse and direct components. End users look for the best compromise between getting close to state-of-the-art measurements and keeping low capital, maintenance and operating costs. Among the existing commercial options, SPN1 is a relatively low cost solar radiometer that estimates global and diffuse solar irradiances from seven thermopile sensors under a shading mask and without moving parts.
This work presents a comprehensive study of SPN1 accuracy and sources of uncertainty, drawing on laboratory experiments, numerical modelling and comparison studies between measurements from this sensor and state-of-the art instruments for six diverse sites. Several clues are provided for improving the SPN1 accuracy and agreement with state-of-the art measurements.