Suitability, sizing, economics, environmental impacts and limitations of solar photovoltaic water pumping system for groundwater irrigation-a brief review.

Abstract

Irrigation is an essential part of agriculture which helps to sustain crop growth and increase food productivity. Most of the nations around the globe have adopted diesel fuel-based pumping units to irrigate their farm lands. However, increased fuel cost and strict emission laws have made these nations to look for alternate and clean energy powered pumping units. Solar water pumping units are more promising alternate to address these concerns. In this review work, types and concepts of available solar thermal and electric energy-based water pumping units are discussed. Suitability of solar PV pumping units in comparison to thermal energy-based units has been listed out. Detailed procedure for sizing solar PV pumping units by considering crop water requirement, head of pump, and local climatic conditions like solar radiation intensity and rainfall have been provided based on inputs from available literatures. In addition, step by step procedure to estimate economics and environmental impacts associated with solar PV water pumping units along with results of latest studies in these areas have also been presented. Solar PV water pumping units are highly recommended for regions with at least 300 to 400 mm rainfall per year and 2 km away from local grid power supply. Moreover, operation of solar PV water pumping units in on-grid mode can reduce its payback period significantly. Pumping cost associated with diesel units are 300.0% higher than solar PV units. Hence, solar PV water pumping units can be considered as an effective and sustainable option to irrigate farmlands. Advantages, limitations of solar PV water pumping, and strategies to improve its acceptability among farmers have also been provided.