Council on Tall Buildings and Urban Habitat
Clean Air Tower
Alex Balchin

First Prize Winner
Site: Tianjin, China
Institution: University of Nottingham

Competition: CTBUH 3rd Annual Student Competition - 2014 Towards Sustainable Vertical Urbanism

Section Rendering
Images of Current Air Condition & Rendering
Skygarden View
Residential Plan
Building Life Cycle
Building Life Cycle Diagram
View from Atrium

Clean Air Tower

Pollution carried by emissions of PM2.5 particles in Tianjin led to the premature deaths of 1,200 residents in 2011 alone, whilst increased levels of smog across China have sparked reports of “crazy bad air”, carrying significant health and financial costs.

The ‘Clean Air Tower’ combines vertical architecture with industrial air-cleaning technologies and self-generated power, making use of the stack effect to clean 8,500,000 m3 of air per year for residents, office workers and the citizens of Tianjin.

Air is accelerated through the south facing solar chimney reaching a simulated 8-10ms-1. The air current drives wind turbines at the peak of the tower generating electricity. This electricity is used to power electro-static precipitators to ionise soot and PM2.5 particles in the air current and collect them at oppositely charged plates inside the chimney. This way the toxic particles are sucked out of the air current which is expelled from the peak of the tower, providing clean, healthy air for approximately one square mile of Tianjin.

A separate system of venturi scrubbers is powered also, providing clean air for workers and residents inside the building. This makes the tower the healthiest and safest place to live and work in the city, allowing people to escape the toxic smog and not fear for their health and the health of their children.

All of these air cleaning processes are celebrated and on show in the atrium, visible from every floor, the under croft above the atrium and a special viewing deck at the peak of the tower. This industrial aesthetic is carried throughout the building and goes hand in hand with the expressed mega-structure steel frame.

The tower is modular allowing it to be constructed in toxic regions of China, then de-constructed and relocated as the air quality is improved. The number of modules stacked up is determined by the toxicity of the air and the office and residential needs of the city. The towers will therefore be slowly toured around China's most toxic regions, removing the hazardous PM2.5 particles created during the city's construction and power generation. When the air quality is safe and stabilised, some of the tower's modules will be deconstructed and could even be sold to other countries in need of air filtration.

Punctuating the modules are sky gardens providing green space for the public and building occupants to enjoy with healthy, filtered air and have room for exercise and sports, activities that are often prohibited in schools due to the dangers of air toxicity.