In the farming region of Bujama in Lima, Peru, the river water used for irrigation is so polluted with heavy metals such as lead, arsenic and cadmium, that the majority of the fresh fruits and vegetables grown here and distributed throughout the capital are contaminated.

So engineering students at Lima's University of Engineering and Technology (UTEC) decided to come up with a solution: a billboard that doubles as both a more sustainable and healthier solution to the problem of crop production in Bujama, and a nifty advertisement for their university. 

Dubbed the 'Air Orchard', this ingenious device has been fitted with 10 dehumidifiers, which filter water from the air into a drip irrigation system that's connected to an urban farm on the ground below. In just one week of operation, the Air Orchard has produced 2,448 fresh heads of lettuce, that are not only free from pollution, but also the pressures of the country's current water crisis. 

Every week this month, the students will be handing out their crops to the locals in an effort to promote their new sustainable urban farm.                        

Now, before you point out that putting the billboard right next to a busy highway and then using all that polluted air to grow crops for human consumption probably isn't the best idea, the UTEC students are way ahead of you. "The technology has a number of filters that purify the water and keep it clean," Ignacio Montero, director of business innovation at UTEC, told Adele Peters at Fast Company. "So, depending on the need, the water generated is ready for human consumption or agricultural use."

Watch the video above to see it in action.

"Though the billboard is an ad for the school, the same technology could be adapted for commercial food production," says Peters. "The key, say the engineers, is to build it in a location that has enough humidity in the air - Lima happens to have muggy air that the system can use to water plants, but in other cities, the technology might not work."

If I lived in Peru, I know which uni I'd be signing up for. These kids are awesome.

Source: Fast Company