Design and performance Analysis of PV-Powered Irrigation Water Pumping Systems

Abstract

In developing countries, diesel engine based irrigation water pumps are widely used. There is a growing awareness that diesel fuels are a limited resource and firing of these fuels is the primarysource of greenhouse gases and global warming phenomena along with the gradual removing of fossil fuel subsidies, make the deployment of such systems very costly and therefore unfavorable. So, this recognition is elevating the interest and activity toward the development and application of alternative sources of energy, such as solar energy to displace the use of diesel fuels. Solar energy is undeletable, environmentally friendlyresource with smallrunning cost, great dependability, and free of charge in its primary radiation form. It needs low maintenance and repairs and are well-matched for isolated and faraway sites, which maintain the possibility to be a substantial role for social and economic growth.

The main objectives of this thesis are to 1) evaluate the flow of energy production for best sizing of PV water pumping system based on the required hydraulic energy for a deferrable load (i.e. load to be shifted with time) such as a drip and flood irrigation methods on a monthly basis and modelling the different elements encompassing the PV water pumping system, considering its efficiencies and the tilt angle influence of PV array on the best sizing of a PV system. For this purpose a study site was selected which is “New Kalbsha” in Lake Nasser Region in south of Egypt; 2) perform an economic analysis using the Levelized Cost of Energy (LCOE) indicator and environmental analysis of PV system compared to the traditionally powered diesel and electric grid-based systems.

The main results showed that 1) the determined PV system size is optimal in which the load almost consumes all the energy produced by the proposed PV generator during the summer months (peak loading); and the PV generator satisfies the demanded hydraulic energy for the whole year with minimum surplus energy production during the off-peak months; 2) The optimal time-based tracking type was found to be the seasonally based tilt angle for the one-axis tracking type for each PV technology; 3) the LCOE, after adding the real costs of different power sources (i.e. the external costs to communityproduced by pollution and its subsequent problems, comprising destruction to the community health and the surrounding atmosphere), of PV driven pump is the lowest value with a value of 0.071, 0.070, 0.069 and 0.067 ($/KWh) for Debt Ratio (DR) of 100%, 75%, 50% and 0% respectively and for engine driven pump, the LCOE is 0.220, 0.217, 0.215 and 0.210 ($/KWh) for DR of 100%, 75%, 50% and 0% respectively, and the LCOE of electricity driven pump is 0.193 ($/KWh) for DR of 0%; 4) the PV driven water pumping system is the cleanest choice compared to the other alternatives as the net GHG emission is 14451.02, 17756.42 and Zero (tCO2/year) for engine driven pump, electricity grid driven pump and PV driven pump respectively.

The conclusion is the deployment of PV driven pump is an economic and a viable alternative to provide power to off-grid ruralsocieties in the harshareas. The present workrevealed that the LCOE and GHG emission of electricity produced by PV system are extrabeneficial in comparison with those produced by a diesel and/or grid electricity production system.

Key words: Solar Energy; Photovoltaic (PV); Irrigation Water Pumping; Optimal Sizing; RETScreen Software; Economic Analysis; Reduction in CO2 Emissions