Access to electricity can bring about a transformative change in the economic conditions and growth of any country. Decentralised solar energy solutions like solar lanterns, solar home lighting systems, rooftop Photovoltaic (PV) systems, and solar micro-grids and mini-grids have been in use for quite some time. In this study, for select sites considered in Karnataka, we analysed the feasibility of Solar PV Micro Grids (SPVMGs), considering its potential as a promising solution for electrifying rural homes and villages.
We conducted a detailed techno-economic analysis of a SPVMG. Broadly, the analysis revealed that the cost of generating and supplying power from a SPVMG, for the sites considered in Karnataka, is in the range of INR 31-34/kWh, which is much higher than the retail electricity rates in India. This suggests that SPVMGs can be an ideal solution when the cost of electricity supply through grid extension exceeds the cost of electricity from SPVMGs. We also observed that trading off between cost and reliability of supply is essential in stand-alone (off-grid) SPVMGs. Restricting the battery discharge to 12 hours (between 6 PM to 6 AM) provides reasonably good reliability at slightly lower Levelised Cost of Electricity (LCOE), as compared to allowing 24x7 discharge of battery. Key aspects of the study included simulating the generation characteristics of a SPVMG; calculating the battery life based on different dispatch strategies; and conducting a scenario analysis to help find a suitable or close-to-optimal system configuration. A financial model, developed for SPVMG analysis, was used to evaluate the economic feasibility of technically appropriate system sizes.