Gas boilers identified as main contributor to NOx pollution in central London

The research found that the combustion of natural gas in boilers for heating accounted for 72 per cent of NOx emissions within a few kilometres’ radius of the BT Tower between 2021 and 2023. 

Transport

The findings highlight the success of transport interventions, such as the London Low Emission Zone and the Ultra Low Emission Zone (ULEZ), in reducing NOx emissions from vehicles.

NOx emissions from vehicles in central London are estimated to have fallen by about 73 per cent between 2016 and 2025. The prevalence of Euro 6 vehicles and electric cars has contributed to this decline.

The study,  published in Environmental Science & Technology, was led by Professor James Lee, professor of atmospheric chemistry at York University. 

Air quality

“Our research highlights how much NOx emissions from transport have improved, but also the task still ahead in getting combustion out of cities,” he said in a statement. “Whilst talk of switching from gas to heat pumps is mainly framed around the decarbonisation benefits, it would be a major gain for air quality too.”