Walls may be the next frontier in in urban farming, allowing residents of large buildings to cultivate food for local consumption. Already, rooftop gardens are already fairly common, the use of exterior walls for growing spaces is still considered problematic. While certain strains of edible greens might grow in a “vertical farm”, root vegetables, tubers and fruits aren’t exactly practical options. However, a vertical algae farm just might work, and provide urban residents with a source of nutrition while it cleans the air.

That’s the idea behind Italian architect Cesare Griffa’s new concept, which is known as the WaterLilly system. Basically, this algae-filled structure, which can be attached to the façade of a building, is made up of a series of individual chambers that contain algae and water. After a few days or weeks, the algae can be harvested and used for energy, food, cosmetics, or pharmaceuticals, with a small amount left behind to start the next growing cycle.

In addition to being completely non-reliant on fossil fuels, these algae also take in carbon dioxide and produce oxygen while growing. Compared to a tree, micro-algae are about 150 to 200 times more efficient at sucking carbon out of the air, making them far more useful in urban settings than either parks or green spaces. Unfortunately, public perception is a bit of a stumbling block when it comes to using microorganisms in the pursuit of combating Climate Change and pollution.

As Griffa himself remarked:

Micro-organisms like algae are like bacteria–it’s one of those things that in our culture people try to get rid of. But algae offer incredible potential because of their very intense photosynthetic activity.

Each system is custom designed for a specific wall, since it’s important to have the right conditions for the algae to thrive. Too little sun isn’t good for growth, but too much sun will cook the organisms. Griffa is working on his first large-scale application now, which will be installed in the Future Food District curated by Carlo Ratti Associates at Expo 2015 in Milan. And it won’t be the first project to incorporate algae-filled walls. A new building in Germany is entirely powered by algae growing outside.

But as Griffa indicates, there’s no lack of wall space to cover, and plenty of room for different approaches:

Urban facades and roofs represent billions of square meters that instead of being made of an inanimate material such as concrete, could become clever photosynthetic surfaces that respond to the current state of climate warming.

And in that, he’s correct. In today’s world, where urban sprawl, pollution, and the onset of Climate Change are all mounting, there’s simply no shortage of ideas, nor the space to test them. As such, it is not far-fetched at all to suspect that in the coming years, algae farms, artificial trees, coral webbing, and many other proposed solutions will be appearing in major cities all over the world.

Source: fastcoexist.com