Towards net-zero power in western India by 2050: Modeling nuclear and BESS expansion under regional policy constraints

With India committing to net-zero emissions by 2070, region-specific, long-term capacity expansion planning has become essential to facilitate a sustainable and economically viable energy transition. This study focuses on the western regional grid of India – one of the country’s five interconnected power regions – to explore least-cost, low-carbon transition pathways using the open-source modeling platform Switch 2.0.7. A total of 71 future scenarios are simulated to evaluate alternative energy-mix strategies for 2050 under varying policy constraints, thermal phase-out levels, and solar penetration levels. The study investigates whether full decarbonization is achievable without nuclear additions and, if not, identifies the minimum nuclear and battery energy storage system (BESS) requirements to ensure zero unserved load. Results indicate that a 75% reduction in existing thermal capacity is feasible with minimal nuclear expansion, while the most robust scenario includes 11.26 GW of new nuclear capacity and 152.4 GW of energy storage. To enable this transition, an estimated annual investment equivalent to 2.5% of the combined GDP of the region’s states will be required over the next 25 years. These findings offer critical insights for policymakers, emphasizing the importance of strategic, region-specific planning and investment to meet India’s long-term climate goals.