Comparative Sensitivity Analysis of Grid-Scale Battery Storage Technologies: Feasibility Investigation for Solar Integration in India

Abstract

This study presents a comprehensive techno-economic and environmental sensitivity analysis of integrating grid-scale solar photovoltaic systems with multiple energy storage technologies to fulfill state-level electricity demand in Jharkhand, India—a resource-rich and coal-dependent state facing persistent grid reliability challenges. Addressing a critical research gap in sector-specific, multi-chemistry storage optimization under dynamic tariff regimes, the study models and compares four storage technologies—lithium ferro phosphate batteries (LFP), sodium-sulfur batteries (NaS), vanadium redox flow batteries (VRFB), and pumped hydropower storage (PH), each tailored for six-hour charge retention. The open-source Solar Alone Multi-objective Advisor (SAMA) tool, used to model PV-battery hybrids, has been used with particle swarm optimization. One hundred and twenty-eight system configurations were simulated across fixed and time-of-use tariffs, with and without net metering, under varying inflation (5%–12.5%) and grid price escalation rates (−2.5% to +5%). The analysis rigorously assesses each configuration's payback period, internal rate of return (IRR), return on investment (RoI), levelized cost of energy (LCOE), emissions, and system sizing metrics. The results show that LFP batteries consistently deliver the shortest payback periods (8–13 years), the highest RoI (43%–340%), and the most stable IRR (9%–13%) under all market scenarios, marking them as the most bankable near-term solution for daily cycling. Pumped hydropower provides moderate payback periods (10–18 years) and achieves highly competitive LCOE values (USD 0.03–0.04 per kWh with net metering), making it ideal for large-scale, long-duration storage where suitable sites exist. Sodium-sulfur batteries reach RoI up to 288% in high-inflation scenarios but display greater volatility, while vanadium redox flow batteries, with payback periods of 11–22 years and no mid-life replacements, offer unique advantages for deep-cycling, stationary industrial applications. Net metering emerges as a dominant policy lever, reducing LCOE from USD 0.06–0.16 per kWh (no export) to USD 0.03–0.04 per kWh (with export) and cutting lifecycle emissions from 0.45 to 0.17 kg/kWh, while enabling a surge in optimal installed PV capacity from 3–5 GW to over 16 GW. The findings accentuate that while LFP offers superior financial performance and rapid capital recovery, sector-specific technology mapping is essential to maximize grid resilience and renewable integration by deploying NaS and PH for medium and bulk storage, and VRFB for industrial deep cycling. Ultimately, the study provides a replicable, data-driven framework for selecting and optimizing storage technologies under evolving market structures, supporting Jharkhand's and similar regions' transition from coal reliance to a resilient, renewable-powered future.