DESIGN AND COST ANALYSIS OF A 500 KVA SOLAR-INTEGRATED PUMPED HYDRO STORAGE SYSTEM

Abstract

In this paper, design and performance analysis of 500 KVA pumped-water-energy storage solar integrated power plants is presented. Akwa Ibom State University, main campus is chosen as the case study site in order to proffer innovative design to improve the current poor power supply in the University. Akwa Ibom State University Main Campus is characterized with geo-coordinates of 4.621437 latitude and 7.763922 longitude, daily mean sunshine hours of 7.13 hours, mean ambient temperature of 26.74 °C and an annual mean solar radiation of 6.22 kW-hr/????²/day. The case study is a 24 hours per day power supply system with daily energy demand of 9,600.0 KWh/day which requires hydro turbine with water flow rate of 1.45 ????³/s and pumped water storage reservoir capacity of 413,498.94 ????³ to accommodate 3 days of power autonomy. With reservoir water head of 30 m and 7.13 hours of pumping water per day, 40 parallel pumps are required each having a flow rate of 0.1342????³/???? and power rating of 47.638 KW. With solar radiation of 6.22 peak sun hours per day it requires a total of 11,458 PV modules, each rated at 300W to form a 3,437.528 KW PV array to power the pumps. Also, a total inverter size of 10,421???????????? is required, split into 40 units of 260.521KVA inverter, one for each of the 40 water pumps. The efficiency of the solar power segment alone is 63.5%, the efficiency of the hydro power segment alone is 70.7% while the combined efficiency of the solar hydro plant is 44.9%. In all, careful combination of direct supply and pumped water storage is needed to optimize the system efficiency