This report was prepared by Mads Brix Nielsen and Mikkel Sorensen of the Technical University of Denmark. Report served as the basis evaluating the Tonga Outer Island Solar Electrification Programme, an evaluation requested by the Tonga Energy Planning Unit (EPU) through the SPC and carried out as a midterm study at the Technical University of Denmark entitled "An Evaluation of Tonga's Outer Island Electrification Programme".