Impacts of the Minamata Convention on Mercury Emissions and Global Deposition from Coal-Fired Power Generation in Asia

Abstract

We explore implications of the United Nations Minamata Convention on Mercury for emissions from Asian coal-fired power generation, and resulting changes to deposition worldwide by 2050. We use engineering analysis, document analysis, and interviews to construct plausible technology scenarios consistent with the Convention. We translate these scenarios into emissions projections for 2050, and use the GEOS-Chem model to calculate global mercury deposition. Where technology requirements in the Convention are flexibly defined, under a global energy and development scenario that relies heavily on coal, we project ∼90 and 150 Mg·y–1 of avoided power sector emissions for China and India, respectively, in 2050, compared to a scenario in which only current technologies are used. Benefits of this avoided emissions growth are primarily captured regionally, with projected changes in annual average gross deposition over China and India ∼2 and 13 μg·m–2 lower, respectively, than the current technology case. Stricter, but technologically feasible, mercury control requirements in both countries could lead to a combined additional 170 Mg·y–1 avoided emissions. Assuming only current technologies but a global transition away from coal avoids 6% and 36% more emissions than this strict technology scenario under heavy coal use for China and India, respectively.