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Abstract In achieving net-zero emission by 2050 due to the Paris Agreement, Indonesia should reduce the atmosphere's gas emissions. Sequestration of carbon dioxide (CO2) in depleted oil and gas reservoirs is an immediate, cost-effective option to reduce CO2 emissions into the atmosphere. The development model of CO2 sequestration is the element implemented in the contract. Therefore, it is necessary to perform evaluation and research to make CO2 sequestration technically and economically feasible. For the technical aspect analysis, a reservoir simulation is executed in a depleted gas field for 30 years of CO2 injection. This simulation study is completed using a 3-D compositional simulator "ECLIPSE 300" to forecast the performance of CO2 storage capacity. In addition, several injection rate sensitivity was conducted to find injection rate effects on the storage capacity and financial performance. The economic analysis takes into account factors such as storage and transportation cost. The analysis of the economic model contract for CO2 sequestration refers to the existing oil and gas contract model in Indonesia, which is Production Sharing Contract (PSC) Cost recovery and Modification of PSC Gross Split. The modification of PSC to evaluate the economic CO2 sequestration project is preferred since it is more acceptable for the government and investors. Based on technical analysis, a series of injection rate sensitivity explained the best scenario for CO2 sequestration. The scenario 60 MMSCFD injection rate was chosen as the best scenario because of its 16 years plateau time. This scenario continues with the economic calculation and study sensitivity for several fiscal parameters to find the most profitable model contract for CO2 sequestration in the depleted gas reservoir. The Cost Recovery model provides better economic returns for contractors. Economic sensitivity shows that several parameters such as CO2 price, amount of CO2 injection, and CAPEX have a considerable influence on the economy.