Professor points out data showing better air quality

Staff writer, with CNA

Mon, Sep 10, 2018 - Page 3

A drop in coal use for power generation was the main reason for improvements in air quality recorded in Taichung, Nantou County, Yunlin County and Chiayi County from January to June, said Tsuang Ben-jei (莊秉潔), an environmental engineering professor at National Chung Hsing University.

A comparison of average levels of PM2.5 — the concentration of airborne particulate matter smaller than 2.5 micrometers — indicated that the average air quality index for the first six months of the year was lower in 20 of Taiwan’s 22 cities and counties than for the same period from 2013 to last year.

On Saturday, Tsuang posted on Facebook data compiled by the Environmental Protection Administration as evidence that air quality in the areas seemed to be improving.

According to the data, the average PM2.5 level from January to June was 29 micrograms per square meter in Taichung, 34 in Nantou, 31 in Yunlin and 33 in Chiayi, representing a decrease of 5 micrograms per square meter in Taichung, 4 in Nantou, 4 in Yunlin and 3 in Chiayi, compared with average levels for 2013 to last year.

Tsuang attributed the improvement to the substitution of coal with liquefied natural gas for electricity production and to the coal-fired Taichung power plant reducing its power-generating capacity by 10 percent, or 2,419 gigawatts per hour, over the same period.

About 70 percent of the decrease in electricity output was made up for by the gas-fired Tongxiao power plant in Miaoli County, Tsuang said.

His argument is corroborated by Taichung, Chiayi and Nantou having received less rainfall from January to June this year than for the same period from 2013 to last year, he said.

Low rainfall eliminated the possibility that airborne particles were simply washed away, lowering the PM2.5 concentration levels, Tsuang added.