A ground-breaking new study has revealed that modern coal-fired power stations produce more ultrafine dust particles than road traffic and can even modify and redistribute rainfall patterns.
The 15-year study indicates filtration systems on modern coal-fired power stations are the largest source of ultrafine particles and can have a multitude of climate impacts.
Previously, road traffic in urban areas was considered to be the main source of small particle emissions which have the potential to adversely affect health and the environment.
In the Bulletin of the American Meteorological Society, Professor Wolfgang Junkermann from the Karlsruhe Institute of Technology in Germany and Professor Jorg Hacker from Airborne Research Australia highlight how coal-fired power stations emit a significant amount of ultrafine particles (UFP) through filtering technology of exhaust gas.
The key findings of the long-term study are:
- Modern coal-fired power stations emit more UFP than urban road traffic.
- UFP can harm human health.
- UFP can affect rainfall distribution on local to regional scales by increasing the condensation nuclei count.
- UFP can be transported in layers with high concentrations for hundreds of kilometres and then lead to localised ‘particle events’ (dramatic spikes in short-term particle concentrations on the ground) far away from their source.
Further to this, the researchers found UFP concentrations have increased continuously since modern coal-fired power stations were commissioned in many locations around the world.
With a diameter of less than 100 nanometers, UFP has an enormous impact on environmental processes, capable of influencing the properties of clouds and precipitation.
To study the existence and distribution and transport processes of UFP in Europe, Australia, Mexico and Inner Mongolia, the research team used two rather unusual small research aircraft – the world’s most comprehensively instrumented motor glider in Australia and a ‘trike’ developed in Germany (considered to be the smallest manned research aircraft worldwide).
The flying laboratories were equipped with highly sensitive instruments and sensors measuring dust particles, trace gases, temperature, humidity, wind and energy balances.
“Our two research aircraft are particularly suitable to follow the plumes from the smoke stacks downwind for hundreds of kilometres and study their behaviour in detail,” says Professor Hacker.
The researchers not only flew their instruments near to or downwind of coal-fired power stations but also over remote regions where very low UFP concentrations have been measured in the past at ground level.
Professor Hacker said that they found fossil power stations have for many years become the strongest individual sources of ultrafine particles worldwide.
“They massively influence meteorological processes and may cause extreme weather events, including intensive rain events. By redistributing rainfall events, this can lead to drier than usual conditions in some places and to unusually heavy and persistent strong rainfall elsewhere.”
In regions with conspicuous precipitation trends such as inland Western Australia and Queensland, the researchers also discovered that UFP concentrations have increased consistently and could be linked to emissions made by coal-fired power stations and refineries.
The full paper can be found online here.