‘Forest cities’ could help solve China’s air pollution problem

Not long ago, Stefano Boeri Architetti announced their plans to create the first ‘vertical forest’ in China. The building would be covered in over 3,000 plants and absorb 25 tons of CO2 per year and produce 60 kilograms of oxygen per day. The goal of the project was to help rectify one of China’s biggest problems: air pollution.

The Nanjing Vertical Forest is a start in creating cleaner air for the country, but its small scale means it can only do so much. An entire city of vertical forests, however, may be able to provide the boost in air quality the country needs. Stefano Boeri Architetti’s new vision for China is to create ‘forest cities’ where every building is a vertical forest, covered in greenery and cleaning the air.

The cities would have the appearance of a post-apocalyptic city in the process of being reclaimed by nature. Only, where the streets of a post-apocalyptic wasteland would be empty and the infrastructure a crumbling mess, these forest cities would be bustling hives of activity, just like any other city.

The first of these sustainable mini-cities would be located in Luizhou, a Chinese city of about 1.5 million people, the Guardian reports. Another of these forest cities is being conceived around Shijiazhuang, a city that is consistently among China’s ten most polluted.

Forest City Shijiazhuang would consist of five districts (petals) each hosting 20,000 residents. Each petal would be a mixed-use environment with residential housing, offices, retail spaces, public spaces, and gardens. The growth of Forest City Shijiazhuang would focus on the vertical space, and reduce urban sprawl.

It is estimated that every square meter of a Vertical Forest façade will absorb 0.4 kilograms of CO2 per year, which means the plants housed in the vertical facades of the buildings will absorb about 1,750 kilograms of CO2 per year collectively, and that isn’t even including the plants located in the parks and gardens.

The vegetation on the outside of the buildings will absorb CO2, but will also help with cooling costs. In the summertime the vegetation will reduce the heating of the facades by up to 30 degrees and create a natural difference in the inside and outside temperature of about three degrees, further adding to the sustainability of the city.

While much of the recent data has pointed toward making cities denser in order to make them more sustainable, Boeri thinks these mini-cities of 100,000 people or fewer and constructed of green architecture are a more sustainable solution than huge, densely populated cities of 10 to 20 million people.

Boeri told the Guardian the firm is already working on designing the different buildings for the forest city proposal. The first forest city could even begin construction by the end of this year and be completed by 2020.

Image courtesy of Stefano Boeri Architetti.