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.
