Seawater greenhouse
We are all familiar with images of the drought which afflicts the poorest communities on earth; the cracked clay ground, unrelenting sunshine and sad-eyed children are part of our annual charity drives. We think we know what the problem is – there simply is not enough water. But does this have to be the case?
The search for water in the dry places of the world is certainly a matter of life and death, both from day-to-day and in the longer term when it comes to growing food. However, the issue isn’t really a lack of water; the issue is that the vast majority of the easily accessible water in the world has salt in it.
Salt water is not much use for humans. Drinking it is the quickest way to dehydrate yourself to an extreme degree. When it comes to farming, it is possible to farm a small amount with salt water, providing you have saline resistant crops. Unfortunately, the vast majority of natural plant life which we rely on for food has evolved on dry land, far away from high concentrations of salt.
It is for these reasons that the quest to desalinate sea water and make it fit for human use has been such a pressing concern for many years. Many solutions have been provided, but nothing as of yet has truly been cheap and effective enough to change the world. Consequently it has become something of a holy grail. The latest project which offers some serious hope in this regard is the Seawater Greenhouse currently being piloted in Somaliland.
The Seawater Greenhouse is designed to take advantage of the two most abundant natural resources in arid coastal regions: seawater and sunlight. The idea is so simple it is quite amazing that no one has come up with it before. Solar power is used to pump salt water in from the sea which is then desalinated on site. The water is then used to irrigate fields and turned into water vapour which cools and dehumidifies the inside of the greenhouses.
The concept has previously been tested on a small scale in Tenerife, Abu Dhabi and Oman, as well as seeing tests on a commercial scale in Australia. All of this is good progress, but the real value of the Somaliland tests is that the newest system is designed to be “low cost, rugged and modular” – meaning that it can be replicated in the toughest environments on earth.
So far, the test is going extremely well. WIRED reported this March that the first harvest of lettuce, cucumbers and tomatoes has been taken in, and the area has become something of an oasis less than a year after being set up. It is something of a dream at the moment, but it is not beyond the realms of imagination that self-sufficiency could be achieved on the Gulf of Aden – and elsewhere – in the near future.
For the super-rich and governments of the world looking at their next charitable investment, it might be worth considering investing in infrastructure such as that being produced by Seawater Greenhouse rather than sending a truckload of perishable foods which don’t really help to solve the underlying infrastructural issues.
Modern technology is a wonder and it has the potential to solve issues like drought – it just needs proper backing. For more information on the project, visit the Seawater Greenhouse website.
Image: ©Seawater Greenhouse
