Technical paradigms in electricity supply for irrigation pumps: Case of Maharashtra, India

Abstract

Solar photovoltaics are being promoted in various parts of the developing world for irrigation pumps as a clean energy source, for use in remote areas, to provide livelihood generation, and in India, additionally to address issues with grid supply. India has a well-developed system of electricity distribution for irrigation, but socio-political issues in this sector have led to a system with poor quality supply for farmers, and losses for distribution utilities. A technical solution is being sought through the following new paradigms: offgrid solar photovoltaic pumps, grid-connected solar photovoltaic pumps, agricultural solar feeders, and High Voltage Distribution Systems (HVDS). These paradigms have been evaluated in this work considering Maharashtra, a representative state with an agricultural distribution infrastructure similar to many states of India. We conduct a comparison of the ALCC (Annualized Life Cycle Costing) of the different technologies based on the seasonality of irrigation, sizes of pumps, and areal density of connections as reflected in the cost of infrastructure, by using marginal costs for supply of electricity. Energy consumption of five agricultural feeders representing four main agro-climatic zones of Maharashtra, has been considered to provide context. The study finds that offgrid solar photovoltaic pumps are more cost-effective than the current system when operated for more than 875 h annually. Other than that most systems are more likely to be economically suboptimal in comparison to upgrading the current distribution system. Other researchers have proposed that grid-connected solar photovoltaic pumps can be used to encourage farmers to reduce groundwater extraction through the use of feed-in tariffs. This study finds that the economics do not support this contention.