Documents reveal the near doubling of toxic nitrogen oxide emissions from ageing Muswellbrook power station

Exemption: NSW Environment Protection Authority has allowed AGL to emit nitrogen oxide levels from Liddell power station at 14 times best practice international levels.
Exemption: NSW Environment Protection Authority has allowed AGL to emit nitrogen oxide levels from Liddell power station at 14 times best practice international levels.

POWER generator AGL Macquarie was granted an exemption in 2017 to emit toxic nitrogen oxides from Liddell power station at up to 14 times international best practice levels despite Hunter nitrogen oxide pollution already exceeding national standards.

The Liddell exemption was approved by the NSW Environment Protection Authority after AGL received a report detailing the cost of a range of air pollution controls that could reduce nitrogen oxide pollution levels by 85 per cent.

But AGL says the exemption was already in place when it bought the power station from the NSW Government in 2014. The exemption will run until 2022 when the power station is scheduled to close. 

The Liddell exemption is a compelling reason why the Federal Government should stop trying to keep the power station open, said Environmental Justice Australia researcher Dr James Whelan after AGL on Monday rejected a proposal by Alinta to buy the power station.

The EJA obtained the exemption documents and pollution control report under freedom of information legislation.

Ageing: Liddell coal-fired power station near Muswellbrook which is one of the oldest of its type in the world. Instead of requiring greater air pollution technology the EPA has exempted owner AGL from meeting existing nitrogen oxide levels.

Ageing: Liddell coal-fired power station near Muswellbrook which is one of the oldest of its type in the world. Instead of requiring greater air pollution technology the EPA has exempted owner AGL from meeting existing nitrogen oxide levels.

Dr Whelan described the Liddell exemption as a “shocking revelation” that confirmed the NSW Government’s “laissez faire approach to air pollution control”.

“Liddell is licensed to emit toxic pollution at levels that would see other power stations subject to serious enforcement actions,” Dr Whelan said.

The EJA has campaigned for the introduction of air pollution controls in Australian power stations that have been standard in American power stations for more than two decades.

In 2017 AGL was required to submit a report to the EPA on international best practice to control nitrogen oxide emissions.

A redacted version of the Aurecon report, submitted by AGL in July 2017, identified Selective Catalytic Reduction (SCR) as the most effective emission control technology which could reduce emissions to just 50-100mg per cubic metre. The redacted version released to the EJA removed the cost of implementing the control measures.

But instead of implementing air pollution technology AGL was approved to emit 1400 micrograms per cubic metre of nitrogen oxides.

Future: Nitrogen oxide levels are another reason why attempts to keep Liddell power station open should end, say groups including Environmental Justice Australia.

Future: Nitrogen oxide levels are another reason why attempts to keep Liddell power station open should end, say groups including Environmental Justice Australia.

Exposure to oxides of nitrogen irritates eyes, nose, throat and lungs and leads to coughing, shortness of breath, tiredness and nausea. Even low levels of exposure are linked to asthma, reduced lung function and allergies. Coal-fired power stations produce 49 per cent of Australia’s nitrogen oxide emissions.

Liddell has been the focus of a national debate about coal-fired power since 2017 when the Federal Government dramatically opposed AGL’s planned closure in 2022 and opponents proposed a government buyout or alternative buyers.

The EJA argues Liddell should close because the Hunter’s pollution levels, including nitrogen oxides, regularly exceed national standards.

“There are major adverse health impacts from coal-fired power stations in the Hunter that have not been assessed by the NSW Government and are clearly not being controlled,” Dr Whelan said.

AGL said Liddell complied with licence conditions set by the Environment Protection Authority.

“AGL has announced the intention to close Liddell in 2022 when it will be more than 50 years old, and replace its capacity with modern, cleaner more reliable electricity generation,” a spokesperson said.