Authors: Assistant Professor Praveen C. Kolur, Assistant Professor Somalingappa S. Davanageri, Vijaykumar Gaddenagouda Patil, Gururaj Kammar, Chetan Gangaram Bhandawalakar
Abstract: The fast development of renewable energy sources has led to an increased instability of the grid due to the intermittent nature of solar and wind power, while conventional electrochemical batteries are hampered by limitations such as resource scarcity, capacity degradation, thermal runaway hazards, and limited cycle life. For long duration energy storage, mechanical systems using gravity have been proposed as an alternative. The use of elevated masses to store gravitational potential energy, which is then released on demand through a controlled descent. This study provides an overview of gravity battery technologies namely pumped hydroelectric, solid mass towers, mine shaft storage, rail-based slope systems and buoyant ocean storage and discusses how they can be utilized in grid stabilization, industrial peak shaving and distributed energy management. Results show that gravity storage technologies can reach round-trip efficiencies of 70% to 85%, have operational lifetimes of over 30 to 50 years with marginal capacity degradation, and are increasingly cost-competitive for dispatch periods exceeding six hours. Moreover, the repurposing of abandoned mine shafts and obsolete industrial infrastructure supports circular economy principles and diminishes reliance on critical materials such as lithium and cobalt. There are challenges such as limits on structural load, high up-front capital costs, and mechanical fatigue on hoist cables and drive trains. However, the constant technical improvements in automated control, linear motor topologies and hybrid renewables integration are rendering it technically feasible. To summarize, gravity batteries present a sustainable and scalable path to grid resilience and deserve accelerated research, policy support, and industrial scale deployment.
