Alemu, Demiss (PhD)Bekele, Addisu2018-07-022023-11-182018-07-022023-11-182007-07http://etd.aau.edu.et/handle/12345678/5327In this thesis the investigation of the possible use of solar energy for large scale water heating system is conducted for the following sites in Ethiopia: Addis Ababa Tannery, Dire Tannery, Modjo Tannery, and Jimma Hospital. The thesis focuses on simulation of large-scale solar water heating system and its economic analysis. Transient performance of the system is computed using a numerical heat transfer model of a single glass cover flat plate collector solar water heater with riser and header type active system. The various design parameters are gathered from the inside country solar water heater manufacturers and dealer companies and also from the world experience. The meteorological data for simulation was prepared by taking the average of five years starting from 2001 - 2005. From the annual contribution of solar energy to the heating load and the estimated investment cost, the unit solar energy cost and the pay back period of the system for each case were calculated. The result obtained indicates that the unit solar energy cost for all cases are less than that of unit cost of fuel heating. Hence the solar energy is the viable alternative source of energy for large-scale water heating systems in EthiopiaenMechanical EngineeringThesis