Japan’s plan to use ammonia for power could worsen pollution tied to premature deaths: Analysis

TOKYO – Japan’s plan to co-fire coal power plants with ammonia in a bid to decarbonise its electricity sector could increase a different type of air pollution linked to millions of premature deaths globally each year, according to a new analysis.

Burning ammonia does not emit carbon dioxide, but it does release fine particulate matter known as PM2.5, according to a report from the Centre for Research on Energy and Clean Air (Crea). 

Japan’s energy transition plan, which aims to extend the life of its fossil fuel plants by co-firing the facilities with ammonia and hydrogen, has faced criticism as most of its peers pivot more quickly to renewable generation. 

The authors of the report estimated emissions for Jera Co’s Hekinan Thermal Power Station Unit 4, which has been revamped over the past few years to allow it to use both coal and ammonia. 

Co-firing the facility with 50 per cent ammonia would increase total emissions of PM2.5 and precursor gases by 167 per cent through both the shipping and combustion of the fuel, according to the Crea, which is based in Helsinki.

“Air quality in Japan has improved significantly due to decades of scientific research, environmental policy, and investments in air pollution mitigation technologies,’’ co-authors Lauri Myllyvirta and Jamie Kelly said in the report. 

“Our results indicate that Japanese improvements in air quality could be undermined, or even offset, by replacing coal’’ with ammonia, they said.

PM2.5 contributes to as many as eight million premature deaths annually across the globe, and in Japan it leads to roughly 43,000 premature deaths a year, Crea said, citing data from State of Global Air, a website funded by the Clear Air Fund.

The authors said global premature deaths combined with non-fatal health illnesses caused by PM2.5 cost the world economy US$8 trillion (S$10 trillion), equivalent to 6.1 per cent of global gross domestic product, citing World Bank data.

Japan’s Ministry of Economy, Trade and Industry and Jera both said in separate statements that precursors of PM2.5 such as nitrogen oxides and sulphur oxides would not be increased by ammonia co-firing in a thermal power plant.

The fine particulate matter is roughly 30 per cent of the diameter of a human hair. Their small size allows them to settle deep in human lungs and even make their way into the blood, according to the Environmental Protection Agency. Exposure to PM2.5 has been linked to a range of conditions, including cardiovascular disease, Type 2 diabetes, lung cancer and dementia.

Making ammonia requires large amounts of energy, and current production of the fuel generates about 2 per cent of global carbon dioxide emissions.

Producing ammonia with renewable electricity suffers from “methodological constraints, which have prevented widespread use”, the authors said. BLOOMBERG