This data article presents the Global Horizontal Irradiance data acquired at a temporal resolution of one-hour intervals from 12 sites around the island of Mauritius, Rodrigues and Agaleǵa.These data were collected over different durations for different sites.The data acquisition process was conducted via Base stations consisting of a TMF100 Data logger, an MS-802 EKO Pyranometer, a Silicon Irradiance Sensor with an integrated temperature sensor, and an Air Temperature Sensor for data collection and a GPRS (General Packet Radio Service) modem for transmission of collected data to an FTP server.The retrieved data from the FTP (File Transfer Protocol) server had to undergo time alignment as a misalignment of 8 h was observedSuch dataset can be used for solar energy resource anal. and forecasting, photovoltaic system performance anal. as well as bringing awareness regarding the installation of com. solar PV projects.This data set will also help to facilitate data-driven decision-making processes and enhance the understanding and utilization of solar energy resources.