During the next three months, in the center of Eindhoven, a trial is taking place to remove fine dust and soot from the urban air via parking garage ventilation replacing it with clean air released into the city. This will substantially improve the city’s air quality. Never before has there been such scientific research on large-scale urban air purification in public spaces. The ‘Lungs of the City’ project is a collaborative effort between the environmental innovation organization ENS Urban, Eindhoven University of Technology (TU/e), the municipality of Eindhoven and Air Liquide. The purpose of the trial is to provide a large-scale solution for increasing urban air pollution.

Research conducted last year by the Built Environment Department of Eindhoven University of Technology revealed that the technology’s effect on air quality in the center of Eindhoven could be substantial when fine dust and soot is captured in underground car parks and cleaned to be released back into the city. The researchers, led by Bert Blocken, Professor of Building Physics, used computer simulations and models to demonstrate that the potential improvement of city air extends beyond just the direct areas where the air is being cleaned.

This is an impression of the structure above the parking garage on the town hall square of Eindhoven. Photo: B. Rongen

World premiere

In the trial that will soon start, thirty air purification installations developed by ENS Urban will be placed next to the exit of the underground car park on the City Hall square (Stadhuisplein). “For the first time, there will be experiments with large-scale purification of urban air in the public areas of the city. In that respect, it is a world premiere,” says Blocken. An extensive network of high-quality measuring equipment will measure the concentrations of fine dust and soot in a large area around the City Hall square for four months. In addition, weather data will be collected, including wind direction and speed, to map the air movement.

The results of last year’s research by TU Eindhoven in which the reduction of particulate matter concentrations was calculated over the entire city centre using 594 air purification installations. The darker the blue, the greater the decrease. A reduction of 50 percent is achieved in several places. Photo: TU Eindhoven

Lungs of the City

The reason for purifying the air on the City Hall Square is because it is a wind-free spot, where air pollution levels are relatively high due to slow car traffic. “Thanks to our innovative air purification technology, the quality of the air leaving the underground car park is significantly better than the air entering it. Car parks can act as ‘lungs of the city’ and make a positive contribution to the city’s air quality,” says Roel Gijsbers of the environmental innovation company ENS Urban, who originated the concept.

The ‘Aufero’, the air purification installation of the ENS Urban company, of which 30 will be used in this trial. Photo: ENS Urban


Eindhoven city councillor Mary-Ann Schreurs was happy to seize the opportunity to facilitate the validation of the research in Eindhoven: “Because air quality is so poor in various places that it is a danger to the health of our residents and visitors, we must take concrete steps to improve air quality. According to the World Health Organization and the European Environment Agency, fine dust is the most harmful pollution in the urban environment and is even strongly linked to an increased risk of premature death. So it is unacceptable just to state that the air quality is bad based on measurements. The expected contribution of this technique is the promise of a healthier Eindhoven, but it can of course be applied in many more places! As soon as the effect is established, it is important to scale up in the inner city as quickly as possible to make it free of fine dust and soot. To this end, we are also asking the State Secretary for help.”


The test compares the airflow simulations of the TU/e with actual measurements and furthermore provides a public demonstration of the potential of the concept. “If the previous results are achieved in reality, the ‘Lungs of the City’ offers a new and proven solution for the large-scale elimination of air pollution in urban areas,” says Gijsbers. In addition to car parks, the concept can also be applied to eliminate fine dust in and around tunnels, train and bus stations, viaducts and busy traffic intersections. Through this approach, the existing infrastructure functions as the ‘clean lungs’ of the city.

Open collaboration

“This trial is characterized by an open collaboration, which enabled a strong combination of the know-how and expertise from each partner. The open innovation approach helps identify and realize solutions to improve air quality on a large scale,” says Diederick Luijten, Vice President Industrial Merchant Air Liquide North West Europe.