Techno-economic feasibility of solar water pumping system in North-Gujarat region, India

Abstract

North Gujarat region of India is predominantly known for agro based economy. As surface water sources are very much limited in these regions, irrigation mainly depends upon underground water strata available at different water table. (Viswanathan, 2014). Close to 80 per cent of the total irrigated area is dominated by deep and shallow tube wells while canal water covers hardly 20 per cent. Gujarat ranked fourth in terms of energization of pump sets over the past three decades, showing more than fivefold increase in the number of pump sets from 2.62 Lakhs during 1983 to 14.28 Lakhs during 2017 and around 3.5 lakh applications are still pending. The agriculture sector in Gujarat utilizes about 27 per cent of the total electricity supplied by Gujarat Urja Vikas Nigam Limited. Contrarily, out of the net revenue generated by GUVNL, only 3 per cent is contributed by the agriculture consumers owing to highly subsidized rate of 60 paisa/kWh. Solar photovoltaic (PV) pumps are powered by an array of solar panels. Solar PV pumps are designed to operate on DC power produced by solar panels, or on existing AC pump with inverter. Solar pumps are easy to install and are generally “good” for the sustainability of boreholes due to their low extraction volumes spread over eight to ten hours a day. To cope up the ever increasing demand, the Gujarat government has provided solar-powered water pumps to farmers to reduce the burden on existing power plants and encourage the farmers to opt for solar powered pumps for their regular irrigation needs. A study on techno economic feasibility of solar water pumping system at farmers fields was carried out during 2015 and 2016 in the North Gujarat region. The study recommended the farmers to adopt 5 hp solar photovoltaic water pumping system coupled with micro irrigation system to promote eco-friendly daytime irrigation. The North Gujarat region is endowed by abundant solar radiation for 300–315 days with insolation of 4.5–6.5 kWh/m2/day. The system is found quite appropriate in the total head range of 5–85 m. Life cycle cost (LCC) of PV system was found to be 58.5 per cent less compared with diesel pump set, average payback period was found to be about 04 years.