A group of eco-minded architects have come up with a way to make crowded cities more green with vertical forests, skyscrapers covered in trees that intake carbon dioxide and release oxygen.
The Earth is a crowded place. The current estimates put the world’s population at over 7.5 billion, and that number is growing exponentially. Along with that population explosion comes the threat of increased pollution, and nowhere is that more evident than in China.
The city of Nanjing is one of 14 cities in China with a population of over 5 million. More than 8.2 million people call Nanjing home, and that makes it just the 10th largest city in the country. And like many Chinese cities, pollution in Nanjing is a major issue. It’s not as bad as, say, China’s capital of Beijing, where the 24.9 million inhabitants are occasionally forced inside when bad weather makes the air hazardous, but Nanjing’s air quality can be dangerously bad due to the high levels of carbon dioxide in the air. China is working to control its pollution, but that’s easier said than done.
One of the best ways to absorb carbon dioxide is also the oldest – planting more trees. But in a city with a heavy population density that’s not always a realistic option. It’s just not possible to create enough vegetation without massively altering the layout of the entire city, and even then they would still just be moving the pollution around rather than actually dealing with the CO2.
Taking inspiration from their work in Milan, city planners in Nanjing turned to French architecture firm Stefano Boeri Architetti to design a vertical tower in Nanjing, a two-towered building almost completely covered in trees. The idea has attracted so much attention that further vertical forests are being planned for Shanghai, Guizhou, Shijiazhuang, Liuzhou, and Chongqing. If the vertical forests are popular (and profitable), there may be multiple vertical forests throughout Chinese cities within the next decade or so.
The Nanjing design is similar to the Bosque Verticale (vertical forest) in Milan, which was completed in 2014 and consists of two towers. The larger of the two measures 364 feet, while the other is 249 feet. The building is lined with over 730 trees, 5,000 shrubs, and 11,000 perennials and groundcover. It occupies roughly 50,000 square meters of land, but also offers 10,000 square meters of forest that otherwise wouldn’t be in existence.
While the buildings look incredible – and they change with the seasons, giving the structures a constantly shifting look – the main benefit is that it acts like a forest. The trees process the C02, then expel oxygen. While that’s great for any city, in Nanjing it could help to have a practical health benefit.
The Nanjing version of the vertical forest will be significantly bigger than its counterpart in Milan. The two towers will measure 656 feet and 354 feet, and rest on a podium that is itself a few stories tall and will contain several businesses. The taller of the two towers will contain offices, a museum, and a school dedicated to green architecture. The second tower will contain a 247-room Hyatt Hotel, complete with a rooftop swimming pool.
The Nanjing towers will contain 1,100 trees and 2,500 plants. They are expected to be completed in 2018 and the combined vegetation will produce 132 pounds of oxygen each day. That won’t clear the air in Nanjing – it will be a drop in the ocean compared to China’s pollution – but it is a start.