CityTrees: New Lungs for Big Cities

Around 7 million deaths were reported in 2012 due to air pollution. The health hazards of this global threat are evident to us all including lung cancer, ischemic heart diseases, and strokes. Furthermore, the Greenhouse Effect is expected to escalate after the recent withdrawal of the US from Paris Climate Agreement.

Since then, small-scale green initiatives have been introduced to act as lungs for busy cities. One of those ideas is “CityTree” by the Berlin- based Green City Solutions. A CityTree has the same effect of 275 urban trees in filtering air from pollutants like nitrogen dioxide and ozone. It literally “eats” air pollution by absorbing pollutants and converting them into its own biomass. In addition, the cutting edge technology of these air filters allows the tracking of air pollution reduction.

“CityTree” is quite a misnomer for the 13-foot wall of moss. This air-purifying equipment provides public seats on either side, as well as being Wi-Fi ready and self-sustaining with solar panels and rainwater collectors attached. The concrete-heavy zones, which have no room for planting new trees, are the target places for those extraordinary moss-walls.

A CityTree reduces pollution by up to 30 % with a proximity of 50 meters. It requires 99% less space and is 95% more cost-effective than regular trees.

20 CityTrees have been installed in various cities worldwide including Paris, Oslo, Hong Kong, Brussels, and Glasgow. However, city officials in Modena, Italy, have been hesitant about installing CityTrees for security reasons.

Those air cleaners, though,  lack shade as opposed to real trees in addition to being expensive. The cost of one CityTree is $25,000, with which you can buy and plant plenty of ordinary trees in the streets. Similar to all plants, CityTrees need maintenance, care, and sufficient water supply. The effectiveness of those air cleaners in a harsh winter climate is still questionable.