The CityTree is a strange mix of bench and hedge, but is very effective at tackling air pollution. Dresden-based Green City Solutions’ creation has been installed in cities including Berlin, Paris, Amsterdam and Oslo. And now there’s one on Glasshouse Street, near Piccadilly Circus in London.
This four-metre-high vertical garden inhales pollution and exhales fresh air – doing, its creator claims, the work of 275 trees in one per cent of the space. Each holds 1,682 pots of moss which extract particulate matter (PM) – soot, dirt and other pollutants – from the air. Bacteria living on the moss digest PM, and the moss digests the bacteria. Absorbed PM ranges from 0.1 microns wide to ten microns – the smaller particles being the most dangerous, as they can get deep into human lungs and from there enter the bloodstream.
“Polluted air is the cause of one in seven deaths worldwide,” says Green City Solutions CEO Dénes Honus. “Just 10µg of pollutants per m³ of air will shorten a life span by half a year.”
And it’s much-needed help. A joint report issued this week by four Parliamentary select committees concluded that air pollution in the UK caused 40,000 deaths and cost the economy £20 billion per year, and that the government had to do more to solve the issue.
Each CityTree costs €22,000 (£17,600), but buyers might be able to recoup this through advertising, as the units include NFC and iBeacon technology. Also built into the solar powered unit is a Wi-Fi beacon, a rainwater-collection unit, as well as a nutrient tank and irrigation system to allow the assembly to water itself.
The CityTree also contains sensors that gather data from the plants and its surroundings. The frame is customisable too, with options for graffiti protection and a wide range of woods and varnish colours. The vertical beds themselves can be planted to display anything from logos to QR codes. How very digitalis