Study on Carbon Dioxide Storage in Deep Saline Aquifers and Storage Costs to Support Carbon Capture and Storage Investment

This study assessed the potential of East Java to serve as a CCUS hub for storing industrial CO₂ emissions from the industrial clusters of Surabaya, Gresik, and Lamongan. The assessment used geological and geophysical analyses, including well logs, seismic interpretation, static modelling, and dynamic simulation. Petrophysical analysis was used to determine key parameters such as porosity. The Prupuh Formation, located at depths of more than 1,000 metres and overlain by a strong seal, was identified as a prime candidate, with simulations indicating secure storage and good injectivity. While the Prupuh Formation shows favourable reservoir quality, thick marl in the Tuban and OK Formations provides sealing integrity. Geomechanical assessment found no critical risks of fault reactivation. Lifecycle costs were estimated using industry analogues. The study confirms the feasibility and substantial capacity of deep saline aquifers in the East Java Basin, specifically the Nona Structure. Dynamic simulations of 30-year injection using seven vertical wells estimate a storage capacity of 27.61–48.10 million tonnes. Techno-economic analysis indicates that costs depend on the number of wells and infrastructure sharing. Pilot-scale unit costs are approximately US$22.8/tonne, including MMV, while full-scale operations reduce costs to US$4.5–11.1/tonne, demonstrating significant economies of scale. These figures are broadly consistent with global benchmarks, supporting the competitiveness of CO₂ storage in Indonesia.