Impact of “coal to electricity” policy on air quality during heating period over Beijing − Tianjin − Hebei region in China by WRF-Chem model

In the pursuit of enhancing the atmospheric environment quality, the Chinese government has promulgated directives advocating for alternative energy sources and has implemented a suite of regulatory measures, including the “coal to electricity” policy. However, the precise quantification of the policy's impact on air quality remains a challenge. This study employs simulation experiments, comparing a basic scenario with an emissions reduction scenario, to assess the policy's efficacy. The findings indicate that the policy has led to a reduction in the daily average concentration of PM_2.5 in Beijing, Tianjin, Baoding, and Shijiazhuang during the heating period, with decreases ranging from 0.2 − 5.6 μg/m³, corresponding to a reduction of 1 − 6%. Notably, during the severe pollution episode on December 15, 2018, the hourly average concentration of PM_2.5 in the majority of the Beijing − Tianjin − Hebei (BTH) region experienced a decrease between 1.02 − 7.53 μg/m³. Furthermore, the study observed a reduction in the average concentrations of other pollutants across the BTH region in December 2018. Specifically, the reductions in PM₁₀, CO, SO₂ and NO₂ concentrations were within the ranges of 0.42 − 11.47 μg/m³, 0.01 − 0.77 μg/m³, 0.39 − 24.18 μg/m³, and 0.76 − 2.91 μg/m³, respectively. Although the “coal to electricity” policy has only partially replaced residential emission sources, it has demonstrated a significant role in improving air quality within the BTH region. It is recommended that future policy development and refinement be tailored to the specific conditions, with a focus on further advancing energy transformation, such as the substitution of coal, to achieve more comprehensive environmental benefits.