Feasibility Assessment of Open-Pond Microalgal CO2 Mitigation Technology with Implementation of the Kyoto Protocol: A Case Study for Japan

Since the Kyoto conference, new frameworks for greenhouse gases (GHGs) reduction, such as the Clean Development Mechanism (CDM), Joint Implementation (JI), and International Emissions Trading (JET) have been proposed. Implementation of these emerging concepts will change the perspective for biological CO2 mitigation strategies. For example, conducting the CO2 mitigation projects in non-Annex I countries rather than in the Annex I countries will lower both capital and operating costs of CO2 mitigation projects. In addition, in some non-Annex I countries sufficient land might be available for the biological CO2 mitigation, which may not be available in land-short Annex I countries. In this study, the impact of this new framework on feasibility of microalgal CO2 mitigation technology was assessed and the feasibility of microalgal CO2 mitigation for Japan in non-Annex I countries was examined. The results showed that implementing new frameworks will improve the feasibility of open-pond microalgal CO2 mitigation systems. Even with conservative assumptions of productivity of 30 tCO2/ha/yr with no revenue from the byproducts, open-pond microalgal CO2 mitigation is competitive to alternative CO2 mitigation technologies. With some favorable assumptions, CO2 mitigation cost can be within the range of estimated international CO2 prices.