The latest national pollution data shows several Hunter and Central Coast power stations have reported significant increases in toxic emissions while overall power generation dropped.
Last legs. Liddell power station remains the state's largest emitter of PM2.5 particle pollution.
Despite a 31 per cent and 9 per cent drop in generation at Liddell and Bayswater respectively, both pumped more pollution into the air in 2020-21 than the year prior, according to new National Pollution Inventory data.
Liddell more than doubled its fine particle (PM2.5) pollution and almost doubled its coarse particle (PM10) pollution from 2019-20.
Bayswater is NSW's highest polluter of nitrogen oxides and mercury reporting an 81 per cent surge in mercury, and emitting four times more mercury than the next highest Eraring.