Economic modelling of the capture-transport-sink scenario of industrial CO_2 emissions: the Estonian-Latvian cross-border case study

摘要

Industrial CO_2 emissions and opportunities for CO_2 geological storage in the Baltic Region were studied within the EU GeoCapacity project supported by the European Union Framework Programme 6. Estonia produces the largest amounts of CO_2 emissions in the region, due to the combustion of Estonian oil shale for energy production. Owing to the shallow sedimentary basin containing mainly potable groundwater, the geological conditions are unfavourable for CO_2 storage in Estonia. Therefore the main Estonian power company Eesti Energia is searching for CO_2 storage options in the neighbouring regions. The most favourable geological conditions for CO_2 storage in the Baltic Region are found in Latvia in the Middle Cambrian reservoir, sealed by Ordovician clayey carbonate rocks. The total CO_2 storage capacity of 16 largest structural traps exceeds 400 million tonnes (Mt). Two power plants close to the city of Narva, with annual CO_2 emissions of 8.0 and 2.7 Mt were chosen for the economic modelling of the capture-transport-sink scenario using the GeoCapacity Decision Support System (DSS) based on the GeoCapacity GIS database. Two anticlinal structures of Latvia, Luku-Duku and South Kandava with the area of 50_70 km~2 were selected for the CO_2 storage. The depth of the top of the Cambrian reservoir is 1020_1050 m, the thickness 28_45 m; permeability of sandstone is more than 300 mD, and the trap storage efficiency factor 40%. The conservative storage capacity of these structures 40 and 44 Mt of CO_2 respectively will be enough for 8 years. The estimated pipeline length required for CO_2 transportation is about 800 km. The oxyfuel capture technology is applied in this scenario. With a conservative storage capacity for 8 years of emissions, avoidance costs are rated at {EUR}37.4 per tonne of CO_2. The total cost of the project estimated by the Decision Support System using the GeoCapacity GIS is about {EUR}2.8 billion for 30 years of payment period.