Start-up company Green City Solutions has developed a freestanding green air purifier for use in congested cities.  CityTrees is a vertical box covered in moss and lichens with a large surface area to absorb particulates and gases and produce oxygen.  The surface area of the moss allows the “tree” to offer the same benefits as 275 urban trees, a fraction of the space, and cost – and is estimated to capture some 240 tons of carbon dioxide annually.  CityTrees use solar energy for power, collect rainwater, and plant health can be monitored and adjusted remotely.  Currently the trees have been installed in cities in Norway, France, Germany, Belgium, Macedonia and Hong Kong, at a unit cost of $25,000.

(We would love to see a small unit developed for apartments!)

This smart ‘tree’ has the environmental benefits of a small forest

Vertical, moss-covered structures have the same benefits as 275 urban trees.