Techno-economic assessment of solar water heating systems for sustainable tourism in northern Pakistan

Abstract

This study is designed to examine the feasibility of the solar water heating (SWH) system for sustainable tourism in Gilgit-Baltistan (GB) of Pakistan and a tourist resort is taken as a base case. Hot water demand, solar irradiance and economic feasibility are the key parameters considered to investigate the potential of SWH systems using simulation tool T*SOL. Three different types of solar collectors were investigated, based on solar fraction, maximum collector temperature and overall system efficiency. Among these collectors, the evacuated tube collectors (ETC) show high solar fraction, efficiency and CO2 emissions saved as compared to flat plate collectors (FPC) and unglazed collectors (UnGC), for both locations. The ETC shows 75 % solar fraction, 40 % efficiency, and 676 kg CO2 emission saved and payback period of is recorded 6.6 years for Gilgit. While for Skardu, 84 % solar fraction, 36 % efficiency, 756 kg CO2 emissions avoided and payback period of 4.6 years is analysed. Sensitivity analysis based on design parameters such as collector area, tilt angle and tank volume is performed to highlight the important design considerations. Based on the techno-economic analysis, it is concluded that ETC is the most feasible SWH system for the northern regions of Pakistan.