Cloud-milking Extraction of water from fog is revolutionising recovery of forests

Cloud milking, a zero-energy technique to extract water from fog, is revolutionising the recovery of forests devastated by fire and drought.

- Stephen Burgen

The idea began as a pilot project in the Canary Islands. The plan was to exploit the moisture-laden "sea of clouds" that hangs over the region in order to help reforestation. It has been extended to several other countries to produce drinking water and to irrigate crops.

Gustavo Viera, the technical director of the publicly funded project in the Canaries, said: "In recent years the Canaries have undergone a severe process of desertification and we've lost a lot of forest through agriculture. And then in 2007 and 2009, as a result of climate change, there were major fires in forested areas that are normally wet."

Viera said that after the devastating fires they sought ways to deliver water to remote, mountainous areas without creating infrastructure or using fossil fuels to extract ground water from deep wells.

The EU-backed project, called Life Nieblas (niebla is the Spanish word for fog) was intended to mimic the way that the leaves of the local species of laurel trees capture water droplets from fog, by using sheets of plastic mesh erected in the path of the wind. As the wind blows fog through the mesh, water droplets collect and fall into the containers below, which is used to irrigate saplings until they have sufficient leaves to capture the water themselves.