Air pollution in cities is one of the main health problems we face, causing more than 6.5 million deaths premature at one year. We must implement models that avoid source contamination, but meanwhile, we receive innovative proposals to minimize its negative consequences on the population. Such as the use of moss in the urban environment, a very effective natural filter against pollutants that is rarely seen in cities.

The proposal comes from the German startup Green City Solutions, whose solution, called CityTree, is a four-meter-high indoor installation of moss. According to its creators, the wall can absorb as much nitrogen dioxide and polluting particles as 275 natural trees, making it an easy installation to maintain remotely. Of course, while a natural tree costs about 830 euros every decade, a CityTree is priced at 25,000 euros, which they are usually paid for by sponsoring companies.

The company has already installed these “CityTrees” in 25 cities around the world (Berlin, Brussels, Oslo, Hong Kong…); In each place, moss species that best adapt to the climate and environment are selected. The facilities include benches to sit on, solar panels to generate electricity, water collection systems for irrigation, and sensors to control humidity, temperature, water and air quality.