India is poised to take a significant leap in the energy storage sector. NTPC Ltd., the Indian power giant, recently announced the upcoming launch of the nation’s first CO₂ battery, a result of its collaboration with Italian firm Energy Dome. The facility, set to be constructed in Kudgi, Karnataka, will boast a capacity of 160 MWh. This groundbreaking initiative promises to revolutionize the landscape of Long Duration Energy Storage (LDES) technologies, which are essential for the reliable use of renewable energy sources.
How does this technology work?
The system developed by Energy Dome is designed to operate on a closed thermodynamic cycle with carbon dioxide playing a central role. During the charging phase, CO₂ is drawn from a reservoir, compressed into a liquid state, and stored under pressure at room temperature. When energy is needed, the process reverses: the gas evaporates, passes through a turbine connected to a generator, and generates electricity. At the end of the cycle, the CO₂ returns to the original container, ready to start again. The system’s efficiency stems both from the intrinsic properties of carbon dioxide and from the optimization of the thermodynamic process.
Compared to traditional solutions, the benefits are numerous. Firstly, there’s longevity: more than 25 years of operational life, significantly outperforming electrochemical batteries. Additionally, it utilizes 100% of its capacity without limitations on depth of discharge, and its performance remains nearly constant over time. Not least is the versatility of installation: unlike other technologies, there are no constraints related to the terrain, making the system adaptable almost anywhere. Then there’s the aspect of sustainability: no lithium, cobalt, or rare earths, which are increasingly critical due to availability and environmental impact. Finally, the modularity of the structure and the use of standard components ease expansion and maintenance.
When comparing various LDES technologies, the CO₂ battery appears to strike an optimal balance between performance, cost, and versatility. Hydroelectric pumping requires specific geological conditions and has a considerable environmental impact. Lithium batteries, while efficient in the short term, exhibit limitations in prolonged storage and depend on critical raw materials. Compressed air energy storage (CAES) systems also require specific geological formations and generally offer lower yields. Thermal storage struggles to achieve competitive efficiencies and to integrate into modern electrical grid contexts.
Integration into the Indian grid
The project will be executed on a turnkey basis by Triveni Turbine, following an EPC (Engineering, Procurement, Construction) model that ensures integrated management and standardization, facilitating future large-scale adoptions. The involvement of local industry, in line with the “Make in India” policies, adds significant economic and logistical value.
The CO₂ battery will tackle one of the main hurdles of renewables: intermittency. Thanks to its ability to store large amounts of energy for extended periods, sources like solar and wind can finally become reliable and programmable. The system will also provide essential services for grid balancing, such as frequency and voltage regulation, contributing to overall stability in an increasingly distributed generation landscape. With its 160 MWh capacity, the facility will effectively manage load and optimize existing infrastructure.
Looking to the future
This project could catalyze the development of a genuine industrial ecosystem around CO₂ battery technology. Aligned with the self-sufficiency goals promoted by the “Atmanirbhar Bharat” initiative, it will encourage the emergence of local production capacities for key components, stimulating innovation and employment. The commercial rollout will help define industrial standards, optimize processes, and reduce costs through scale effects and accumulated experience.
Shri Gurdeep Singh, head of NTPC, has not hesitated to call it a real breakthrough for the long-duration energy storage sector. Echoing this sentiment, Claudio Spadacini, founder of Energy Dome, highlighted the strategic value of this collaboration: not only new opportunities for the local industry but also positioning India as a global reference for this cutting-edge technology.
NTPC’s adoption of this battery demonstrates how innovation can concretely respond to the challenges of the energy transition. The intuitive design of the thermodynamic cycle, combined with the modularity and use of standard components, makes this solution particularly promising for widespread dissemination.
The 160 MWh pilot project will serve as a testbed to verify performance and gather valuable data for further technical and economic development. If results meet expectations, this technology could become a cornerstone in building an energy future where renewables play a leading role, supported by efficient, sustainable, and scalable storage systems.