Air quality in Taiwan has been gradually improving due to all the outstanding results via various policies, from the introduction of the Air Pollution Control Action Plan (空氣污染防制行動方案) in December 2017 to the currently ongoing Air Pollution Control Action Plan (2020 to 2023). Thanks to efforts by government agencies and local authorities in implementing air pollution reduction measures, the annual average of PM_2.5 concentration had gone from 16.2 μg/m³ in 2016 down to 12.4 μg/m³ in 2022. These improvements have allowed Taiwan to reach its interim air quality improvement goals ahead of schedule.

Continuing to improve air quality and protecting public health is the core of environmental protection efforts. Aside from annual improvement of air quality, pollution of fine particulate matter (PM2.5) in specific seasons and different regions particularly poses a more serious challenge.

Air quality improvement goals
The then EPA had proposed the Air Pollution Control Action Plan (2020 to 2023). It aims to reduce emissions of precursor pollutants that forms PM_2.5 (such as primary particulate pollutants, sulfur oxides (SOx), nitrogen oxides (NOx), and volatile organic compounds) to achieve a national annual average concentration at 15 μg/m³ for PM_2.5 by 2023. To further ensure the public breath good-quality air, the MOENV has introduced an additional goal, aiming to halve the number of days with high PM_2.5 concentrations. Specifically, the annual ratio of days categorized with “good” and “moderate” air quality, meaning whose air quality index (AQI) is not above 100, is to increase by 1% year after year. 

Given the variety and complicated nature of air pollution sources, a diverse set of air pollution control measures is required to effectively lower air pollutant emissions and hence improve air quality. The EPA-proposed has integrated various control practices and formulated the Air Pollution Control Action Plan (2020-2023) include strategies on the four aspects of stationary pollution sources, mobile sources, fugitive sources, and comprehensive problem. It also aims to improve problems of PM_2.5 and ozone by cutting down precursor pollutants of both pollutants. The main features of the plan are as follows:

    In accordance with amendments to the Air Pollution Control Act, efforts have been made to expand the scope and intensity of regulations. This includes stricter emission standards for specific industries, controls concerning fuel composition and ratios of mixed combustion, reduction of existing pollution sources, controls of harmful air pollutants, and regulations on paint coatings for buildings.
    Control of mobile pollution sources has been expanded to include vessel and aviation fuels with ongoing efforts to lower pollution from modes of transportation, such as gas and diesel vehicles and motorcycles. Initiatives to promote electrification of urban buses and harbor management aim to reduce the impact of pollution emissions on public health.
    Continued efforts are being made to enhance pollution control. This includes lowering emissions from boilers and air pollution from state-owned enterprises, reviewing control fees targeting air pollution from stationary sources, and effectively enhancing factory monitoring. Practices that cut down airborne dust on riverbanks and the establishment of green walls are among the control efforts as well.
    Air quality will continue to be monitored and pollution emission data updated while in-depth scientific research will serve as reference for future policies and program evaluations. Moreover, environmental education is to be carried out from a human-centric perspective under the program.
    Efforts to improve response measures during periods of poor air quality are included in the plan, as well as diversification of control strategies and wider participation of both the public and industries. The goal is to mitigate poor air quality during the autumn and winter seasons.

Main achievements (as of the end 2023)
    Lowering of PM2.5 concentration: The national annual average PM_2.5 concentration had dropped from 20 μg/m³ in 2016 to 12.4 μg/m³ in 2022, a 38% reduction. The ratio of the number of days with PM2.5 concentration in “good” or “moderate” categories (AQI≦100) grew from 84.8% in 2016 to 97.3% in 2023.
    Substantial enhancement of air quality in central and southern Taiwan during fall and winter: Actions include collaboration across different regions, strengthened control measures, and, specifically for power plants, practices that reduce the use of coal and increase that of natural gas, and also coordination of power generation facilities. All have led to a remarkable improvement in air quality, namely a 94% drop in red alerts for PM_2.5 in Kaohsiung and Pingtung, from 338 times in 2016 to 19 times in 2022, as well as another 94% drop in Yunlin, Chiayi, and Tainan, from 261 times in 2016 to 16 times in 2022.
    Reduction of air pollution from state-owned enterprises: Since 2016 the overall air pollution emissions from state-owned enterprises saw a 46% in 2023. Such results include a 60% drop of emissions at Taichung Power Plant and a 69% at Hsing-Da Power Plant.
    Boiler improvements and replacement: Approximately 98% of regulated industrial and commercial boilers have either undergone improvements or been replaced. The percentage of gas-fired boilers, which have higher pollution capacities, has grown from 24% to 73%, a threefold increase.
    Less airborne dust along Zhuoshui River: Central and local authorities have collaborated to control and reduce airborne dust along Zhuoshui River, resulting in a decrease by 98%, in which airborne dust incidents went from 59 in 2017 to 2 in 2022.
    Diversified measures for large diesel vehicles: By 2022, the number of large diesel vehicles had dropped by nearly 47%, with approximately 68,000 phased out. Additionally, subsidies were provided for maintenance and installation of pollution control equipment on 14,000 vehicles, further reducing pollution emissions.
    Accelerated replacement of old motorcycles: As of the end of 2022, the EPA had phased out a total of 1,733,000 motorcycles, lowering the number of old motorcycles by 37%.
    Reduction of air pollution in commercial ports: Efforts implemented include urging vessels to reduce speed and use low-sulfur fuels. As a result, monitoring stations near international commercial ports in Taiwan have reported a decrease in sulfur dioxide (SO2) concentrations. The most significant achievement comes from the monitoring station in Siaogang Port in Kaohsiung, which recorded a drop of annual average SO₂ concentration by 64% compared to 2016.
    Electrification of urban buses: By 2022, a total of 1,170 commercial electric buses (excluding tour buses) had been registered and put into service. This is a 4.7-fold increase compared to 2016, when there were just 205 electric buses in operation.

Conclusion
Air pollution has multiple sources and complex causes, making it impossible for the government to rely solely on a single pollution control measures to achieve results. With an invisible adversary that is PM_2.5, it is essential to take a comprehensive approach that entails regulating various sources of pollution, including industrial, transportation, and fugitive sources. It also involves extensive efforts in environmental monitoring and utilization of technology for law enforcement. Moreover, it is only through collaboration among the government, the private sector, and civil organizations can the overarching goal of enhancing air quality and ensure environmental sustainability be accomplished.
 

Excerpt from Major Environmental Policies, July 2023