John Metcalfe was CityLab’s Bay Area bureau chief, covering climate change and the science of cities.
This futuristic tower aims to use solar power to eliminate air pollution.
Despite China's avowed war on pollution, the air above its major cities continues to resemble the grayish pea soup of an airport's smoking room. But designer Alexander Balchin believes he's devised a way to clear up this choking mess: a skyscraper that sucks in dirty air at the bottom and spews it out, fresh-smelling, at the top.
Balchin conceived of the "Clean Air Tower" while doing research on Tianjin, a large northern city that he says incurred 1,200 premature deaths in 2011 due to bad air. The odd-looking building would theoretically harness the sun's power to run foul air through filters, providing a square mile of breathable space in the city.
In the middle of the tower is a hollow "solar chimney" that does two things: It takes in air near ground level and lets it rapidly accelerate upward, making it spin electricity-generating turbines. This juice, in turn, would power "electro-static precipitators" inside the chimney, ionizing the air and separating out dangerous fine particles like dust and soot.
In a nifty, if perhaps not realistic feature, the massive structure would employ a modular design so it could be disassembled and packed onto a train. Balchin explains more:
[T]he number of units stacked up is determined by the harshness of the air and the office and residential needs of the metropolis. the architecture will therefore be slowly toured around most lethal area, removing the hazardous materials created during the city’s everyday activities. when the quality is safe and stabilized, some of the components can be sold to other nations in need of air filtration.
These are concept illustrations of the air filter; the last is a view from inside the solar chimney: