Comparison Between Measured Mean Monthly Solar Insolation Data and Estimates from Swera Database for Salta City (Northwestern Argentina)

Abstract

The lack of measured data for global solar insolation in the Argentine Northwest (ANW) was supplied using free-access databases available on the Internet. For Salta Capital metropolitan region, measured monthly mean global solar insolation and estimated monthly values from SWERA, SoDa and SSE databases are compared. The objective was to determine the degree of correlation of each database with measured values and the origin in found differences. SWERA data happened to be the best correlation, with the measured data (average RMSE% = 14%). The other databases have errors above 24 %, this being attributed to larger satellite grid cells. A linear model, developed using MLR, is presented. It offers better estimates than the databases (RMSE% of 6%), but only applies to Salta Capital.