Clean Air Por Favor – Global Air Quality Requires Local Solutions
Coming back from a month-long break where I got to travel to the motherland, yes home sweet home – India. Of all the things, good and bad, the one thing that stuck was my smartwatch going off about the air quality and how I shouldn’t leave the confines of my home.
As you can see from the list, the top cities with the worst air quality are all in the developing world. With the vast amounts of infrastructure projects, deforestation, and urban congestion, these cities have air quality indexes that are considered unhealthy for humans. Air Quality Index runs from 0 to 500 and is used to communicate how polluted the air currently is. A value under 50 is considered good air quality, and anything above 300 is hazardous.
Even though many cities around the world aren’t in the top 10 list, quite a few of them have an AQI above 150 that qualifies as unhealthy. Different cities have been trying various methods to encourage pollution reduction and to make citizens choose greener options including some European countries banning petrol/diesel based personal automobiles from 2030 onwards.
At the city level, three technology solutions stood out that I wanted to share with you:
- Air Purifying Billboard, Peru
- Smog Free Tower, Rotterdam
- Air Purifying Tower, China
Air Purifying Billboard, Peru
Normally used for showing large scale advertisements, the University of Engineering & Technology (UTEC) in Peru, built a water purification system into a billboard that does the work of approximately 1200 trees. This billboard combines polluted air with water that dissolves bacteria, dust, and germs to deliver 100,000 cubic meters of fresh air daily that is 99% free of airborne bacteria. With minimal electricity usage and completely recycled water, this is expected to benefit residents and workers within a 5-block radius. A key tenet of putting up this billboard is to show how engineering is behind positive innovations and can help change the world.
Smog Free Tower, Rotterdam
Designed to act like a vacuum cleaner, this large tower has been erected in the middle of a park in Rotterdam. This sleek design is the brainchild of Dutch artist Daan Roosegaarde and is a common name in air purification designs. At 23 feet tall, this tower can purify up to 1 million cubic feet of air every hour and can run 24/7 with limited to no maintenance. The technology involved ionizes airborne smog particles without producing Ozone, which is a common by-product of similar ionizing purifiers. Once ionized, the smog particles are given a positive charge, which is then attracted to a negatively charged electrode closer to the ground, so that they are stripped out of the air. The top of the tower acts like a vacuum cleaner and sucks in the air into the chamber, and the cleaned/purified air is given out from the vents at the bottom of the chamber.
Air Purifying Tower, China
Said to be the largest air purifier in the world, China has built this 100 meter (328 feet) tower in Xian to provide clean air to nearby residents. While testing is still in progress, it is expected to deliver better air quality to approximately 10 square kilometers and produces more than 353 million cubic feet of clean air a day. As this tower is primarily solar-powered, it requires minimal external power to run. This tower is in succession to the world’s largest smog removal tower in China by artist Daan Roosegaarde which stands only 7 meters (23 feet) tall. Although this tower lacks the aesthetic appeal of the Smog Tower in Rotterdam, it houses a greenhouse at the base which is about half the size of a soccer field and is said to be a prototype for a full-sized tower that will be at least 500 meters (1640 feet) and have a diameter of 200 meters (656 feet). The principle involved is that the base of the tower sucks in polluted air, which is then heated by solar energy from the greenhouses. As the heated air rises in the tower, it passes through multiple filtration layers that then remove particles from the air, and clean air is given out of the top.
With several intelligent air purifying techniques available, what are you using in your homes or your cities? Do tell us in the comments and let us know if you feel the quality of air in your city impacts your quality of life.
