Pulling much-needed water out of thin air in Peru

Billboards are usually a common sight in cities, particularly large ones.

Billboards are usually a common sight in cities, particularly large ones. As such, they are commonly associated with cosmopolitan urban areas.

As billboards are commonly used for advertising and many people believe advertising is something we are already being bombarded with and see too much of, they are surprisingly controversial.

So, since we already have too many billboards in urban areas, why would anyone put a billboard in the middle of a desert?

Why, to provide drinking water for locals of course.

No, it’s not a joke. There really is such a thing. UTEC (University of Engineering and Technology of Peru) has erected a billboard that extracts water from the air in the region of Lima, Peru.

Water is something that life everywhere in every form depends on. It is also something we do not have nearly enough of. Luckily, science is amazing and people keep coming up with great ideas to tap into previously unavailable water sources.

Lima is the capital and largest city in Peru and is home to between seven and nine million people depending on who you ask (some people will count only the citizens of the city while others count those who live in the metropolitan area surrounding it as well). Many of these people don’t have clean drinking water.

About 1.2 million Limeans lack running water entirely. Instead, these people draw water from wells. Most of these wells are polluted and not safe to drink from.

Those Limeans who have some cash can try buying water from the unregulated, privately owned water trucks but it will cost them a small fortune. Such trucks can charge as much as 20 times the price of what well-off residents pay for tap water.

The country around Lima is what is called a ‘coastal desert.’ Its annual rainfall is less than one inch a year on average. But, because it is near the ocean, it averages between 83 and 100% atmospheric humidity. So, what Lima had was a dangerous water shortage and a massive water source that no one could tap into. All Utec did was make the water in the air drinkable.

This is how it works. The billboard contains an air fi lter and condenser. As air passes through the billboard, humidity is trapped by the fi lter and condensed to become liquid water.

Then, the water passes through a reverse osmosis fi ltration process and is stored in tanks in the billboard. Each of the tanks in the billboard can hold about 20L and it has a total capacity of about 96L. After being fi ltered and purifi ed through fi ve different generators, the water is collected into one large tank and dispensed through a tap at the base of the billboard.

On average, the billboard produces about 100L of potable water each day. In its fi rst three months of operation, it produced 9,450L of drinkable water, enough to meet the needs of hundreds of families.

This is something that would be easy to duplicate in other areas with similar climates (heck, with the humid weather Central Alberta has been experiencing lately, it might even work here, not that we need it). Such water systems could go a long way to preventing water shortages, the spread of water-borne diseases, and could possibly even be used to combat drought.

It’s not really any breakthrough science or state-of-the-art technology. In fact, technology used in the billboard is not dissimilar from that used in a dehumidifi er. It’s just a great idea that no one has had before.

Once again, technology is an amazing thing.