Billboards could do more than just advertise, if scientists at the University of Engineering and Technology (UTEC) in Peru have their way. While UTEC’s earlier billboard produced drinkable water, its latest creation scrubs the air free of pollutants. According to the team, a single billboard can do the work of 1,200 trees, purifying 100,000 cubic meters (3.5 million cubic feet) of air daily in crowded cities.
The University has installed its first air-purifying billboard near a construction zone in Lima, a city that’s famous for having the worst air quality in all of South America. The billboard works by combining polluted air with water, using basic thermodynamic principles to actively dissolve the pollutants (such as bacteria, dust and germs) in water to release fresh air.
The scientists claim that their billboard filtered around 500,000 cubic meters of air within one week in March, scrubbing it free of 99 percent of its airborne bacteria. The effects of the billboard can be experienced, the team says, within a 5-block radius, benefiting both construction workers and the area’s residents. The extracted pollutants are held for analysis, presumably with a view to creating more effective billboards in the future.
The purifying process is continuous, uses 100 percent recyclable water and consumes little energy, the team says – roughly 2.5 kW (2,500 watts) per hour. Ad agency FCB Mayo is helping the University promote the billboard.
“We seek to demonstrate that engineering is behind it all,” says Jessica Rúas, Director of Promotion at UTEC. “And what better way to also show that than through advertising that changes the world, helps the community and cares for the environment.”
—[*Also see](http://time.com/84013/this-billboard-sucks-pollution-from-the-sky-and-returns-purified-air/) [Learn more here](http://www.utec.edu.pe/Lists/Noticias/DispNota.aspx?ID=200#.U2a6UfmSzHR)