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A Bountiful Billboard

Lima, the capital city of the South American country of Peru, is located in the Sechura Desert. This desert region is one of the driest in the world and receives almost no rainfall. Yet more than eight million people live in Lima. Because of the lack of water, one out of every 10 residents has no access to running water. Some people depend on private companies to deliver water to their homes and businesses.

The engineers at the University of Engineering and Technology of Peru (UTEC) thought about how Lima's extreme water shortage problem could be solved. They noticed that even though there was little rainfall in Lima, the humidity(湿度) was high. Due to the city's coastal location, humidity can be higher than 90 percent on summer days. The engineers wondered whether they could make use of the moisture in the air.

The staff at the university realized that this project, while helping the residents of Lima, could also show the public UTEC's engineering program. Thus they formed a partnership with the advertising agency Mayo DraftFCB. The two groups created an advertisement to demonstrate the university's engineering projects. They made a billboard that obtained moisture from the air and turned it into drinkable water.

The engineers used the city's power lines to provide electricity to five condensers(冷凝器) that operate within the billboard. The condensers are cooler than the outside air. When air comes in contact with the condensers, it cools. The water vapor in the air condenses, becoming liquid water. The water then flows through pipes into a storage tank at the foot of the billboard. People can access the water through a tap.

Now the billboard produces 96 liters of water a day. This can supply hundreds of families with water each month. Additionally, UTEC recorded a 28 percent increase of new students since the construction of the billboard. The problem-solving billboard has inspired more young people to choose engineering careers. They want to be part of productive, clever solutions to unresolved problems.