Moss wall for cleaner air in cities

Cities all across the globe are sinking more and more into smog. Air pollution, particularly in the cities is a growing issue that only is getting worse. Even more so, air pollution causes around 7 million pre-mature deaths every year, according to the World Health Organisation. One of the solutions is to reduce the car emissions in the city, since these are one of the largest pollutants in cities. Green City Solutions offers another way to improve the air quality in the urban areas – a solar powered green wall of moss that has the regenerative power of a small forest.


By 2050 around 80% of the world’s population will be living in urban areas, so improving the air quality in cities is an important issue. One solution is to reduce car emissions within cities; another solution is to plant more trees in and around urban areas. However, these solutions might not be viable or too slow; yet Green City Solutions, a Berlin based tech start-up, offer a slightly quicker solution to the air pollution in cities. They have created The CityTree: “The world’s first bio-tech filter to quantifiably improve air quality.” The CityTree is 4 meters tall, 3 meters wide and 2.19 meters deep, and is offered in two versions – with or without a bench. Green City Solutions claims that this wall, which mainly consists of moss culture and some shade creating plants has the same benefit for cleaning up the air as 275 trees. As Green City Solutions writes on their homepage:

“Certain moss cultures have the ability to filter pollutants such as particulate matter out of the air by binding them to the leaf surface and then integrating them permanently into their own biomass. This makes them ideal air purifiers. But in cities, where air purification is a great challenge, mosses are barely able to survive due to their need for water and shade. The combination of shade-giving plants, a fully-automated supply of water and nutrients and cutting-edge Internet of Things technology (IoT) can solve this problem. At the same time, the filter performance and the plants’ requirements can be measured and analysed. Put it all together and you have an intelligent, natural air filter for cities: the CityTree.”


The moss then can remove particulate matter, nitrogen dioxide, and ozone gasses from the air. In addition Green City Solutions’ CityTree is an autonomous installation, and it requires a minimal maintenance. The solar panels on The CityTree provide electricity while the rain water collecting reservoir provides water for the soil. Plus, there are also built in pollution sensors in this green wall, which monitor the local air quality. As CNN writes:

“Its creators say that each CityTree is able to absorb around 250 grams of particulate matter a day and contributes to the capture of greenhouse gases by removing 240 metric tons of CO2 a year.”

Moreover The CityTree is also great for biodiversity, on one square meter it provides home for 1682 plants; thus it not only improves the air quality in the city, but also biodiversity of plants. As of now you can find one of these green walls in 20 metropolitan areas, including Berlin, Essen, Oslo, Paris, Brussels and Honk Kong. Green City Solutions hope to soon work on also introducing the CityTree in cities in India, as the air pollution there is dangerously high. While to some it might not be as pleasing looking for the eye as real trees, it is an innovative solution that combines nature and technology to improve the air quality in the cities. For more information visit Green City Solutions.

Baiba Šustere

Baiba Šustere is a staff writer and wellness expert for My Good Planet. Specialising in mindfulness, health and wellbeing, Baiba's work has inspired and touched many of our readers over the course of her time with us. Her time studying to become a Yoga teacher in India gave her a unique perspective on life; one which she generously shares with us regularly.