High capacity. Proven globally. Distance from population. ONGC infrastructure reuse.
Offshore geological storage is the backbone of global CCUS deployment — Norway's Sleipner and Snøhvit operations have stored approximately 25 MT of CO₂ offshore since 1996, the Gorgon project in Australia's offshore WA stores 4 MT/year, and the Greensand project in Denmark demonstrates cross-border offshore CO₂ transport and storage. The consistent preference for offshore storage in mature CCUS programmes reflects several advantages over onshore: higher storage capacity per well due to greater depths and pressures, fewer surface access and land rights complications, greater distance from potable groundwater and populated areas, and the ability to leverage existing offshore infrastructure.
India has a 7,500 km coastline and an Exclusive Economic Zone (EEZ) of approximately 2.37 million km² — one of the world's larger offshore jurisdictions. Within this EEZ, India's continental shelf hosts the oil and gas fields that ONGC, Reliance, and Oil India have operated for decades, providing substantial subsurface characterisation data that is directly applicable to CO₂ storage appraisal. The most significant offshore storage opportunities are associated with India's major producing basins: the Mumbai offshore basin (Western EEZ), the Krishna-Godavari offshore basin (Eastern EEZ), and the Cauvery offshore basin (Southeast).
The primary challenge for Indian offshore CO₂ storage is the CO₂ transport infrastructure required to connect inland industrial emission sources to offshore injection wells. Major industrial clusters in Gujarat (Hazira, Dahej, Vadodara) are within viable pipeline distance of the Arabian Sea shelf. Industrial clusters in Andhra Pradesh and Tamil Nadu are within range of the Bay of Bengal shelf. However, central India's coal belt — the Gondwana basin industrial corridor in Chhattisgarh, Jharkhand, and Odisha — is too distant from the coast for offshore storage to be economic without onshore intermediate storage hubs, making onshore saline aquifer storage the preferred option for that region.
India's Exclusive Economic Zone — one of the world's larger offshore jurisdictions
India's coastline — providing offshore storage access to all of India's coastal industrial clusters
CO₂ stored offshore in Norway's Sleipner and Snøhvit operations since 1996 — 28 years of safe operation
CO₂ stored annually in Australia's offshore Gorgon project — the world's largest offshore CCUS operation
The Mumbai Offshore Basin — ONGC's most prolific producing region, home to Mumbai High, Heera-Neelam, and B193 fields — contains India's highest-quality depleted reservoir CO₂ storage assets. Mumbai High's carbonate reservoir, though primarily a CO₂-EOR opportunity due to its remaining oil saturation, will transition to a dedicated storage asset as production declines. The Bassein and Panna fields offer saline aquifer storage in the deeper portions of the basin beyond the producing reservoirs. The proximity of Mumbai High to India's western coast industrial corridors (Maharashtra, Gujarat) and existing offshore pipeline infrastructure makes this basin the highest-priority offshore storage target.
The Krishna-Godavari Offshore Basin — India's most prolific offshore gas province, containing Reliance's KG-D6 and ONGC's KG-DWN fields — offers both depleted reservoir storage (as KG-D6 continues to decline from peak production) and deep saline aquifer storage in the Cretaceous and Paleocene formations of the deep KG basin. The basin's location off the Andhra Pradesh and Tamil Nadu coast makes it ideally positioned to store CO₂ from the large cement, fertiliser, and power clusters in these states. ONGC's extensive seismic and borehole data for the KG basin provides a strong characterisation foundation for storage appraisal.
The Cauvery Offshore Basin — off Tamil Nadu — is less explored than Mumbai or KG but has potential depleted gas reservoir storage in the Paleocene-Eocene section and deep saline aquifer potential in the Cretaceous. Co-located with Tamil Nadu's significant coal power, cement, and petrochemical capacity. NCM's offshore storage programme includes a preliminary Cauvery assessment using ONGC and Hardy Oil data from the basin's exploration history.
Every major offshore CCUS operation provides specific technical and regulatory lessons that NCM applies to India's offshore storage programme development.
India's offshore CO₂ storage regulatory framework will be built on three existing legislative pillars: the Territorial Waters, Continental Shelf, Exclusive Economic Zone and Other Maritime Zones Act (TCZMA), which governs all activities in India's EEZ; the Oilfields (Regulation and Development) Act (ORDA), under which DGH currently regulates offshore oil and gas operations and which will need CO₂ storage-specific amendments; and the Environment Protection Act, under which MoEFCC will require environmental impact assessments for offshore CO₂ injection activities.
NCM's regulatory advisory for offshore storage is developing a draft Offshore CO₂ Storage Bill for consultation with the Ministry of Petroleum and Natural Gas — modelled closely on Australia's OPGGS Act (Offshore Petroleum and Greenhouse Gas Storage Act), which is the world's most comprehensive offshore CO₂ storage legislation. The OPGGS Act's structure — greenhouse gas assessment permits, greenhouse gas holding leases, greenhouse gas injection licences, and greenhouse gas search authorities — provides a complete regulatory lifecycle framework that India's DGH can adapt for the Indian EEZ context with relatively minor modifications.
For India's first offshore CCUS projects — likely to be CO₂-EOR operations in the Mumbai or KG basin within the existing ONGC production sharing contract framework — NCM is developing an interim regulatory pathway that adds CO₂ storage-specific conditions to existing petroleum operation approvals, enabling projects to proceed before comprehensive stand-alone legislation is enacted. This approach mirrors how Norway managed Sleipner's first decade of operations under petroleum legislation before specific CO₂ storage regulations were implemented.
Whether you are a government body seeking policy advice, an industrial company facing CBAM exposure, or an investor seeking CCUS project opportunities — our team is ready to engage.