Role of CO2 sequestration by country for global warming mitigation after 2013

Abstract

This chapter evaluates CO2 sequestration technologies in parallel with other mitigation technologies and also in consideration of their regional differences. Five kinds of CO2 sequestration technologies are modeled: enhanced oil recovery, depleted gas well sequestration, enhanced coal-bed methane, aquifer sequestration, and ocean sequestration. The divided regions are interlinked through transportations of CO2 and various kinds of energies. The model is an intertemporal optimization type; the objective function is the total cost of energy systems plus CO2 sequestration between 2000 and 2050. Energy supply systems and CO2 capture and sequestration technologies are represented in the bottom-up fashion in order to evaluate technological strategies of CO2 emission mitigation technologies. CO2 sequestration potentials of the 77 divided regions were estimated based on several geographical information systems (GIS) data. The model analysis results show that CO2 sequestration accounts for a large part of the total CO2 emission reduction; the amounts of the cumulative world CO2 sequestration between 2000 and 2050 are about 45 GtC and 65 GtC with and without emission trading, respectively, and that the cost effective strategies differ by region. In the emission trading case, all the four types of underground CO2 sequestration technologies are utilized for US; the sequestration into ocean and aquifer are utilized for Japan. CO2 sequestration technologies would decrease the world marginal cost of CO2 reduction in 2050 by about 59 $/tC.