The Sahara Desert is one of the world's largest and driest deserts. Encompassing 3,500,000 km or about 10% of the continent of Africa, the desert comprises of miles and miles of sand dunes, an environment in which very little can thrive. However, a radical new idea may soon transform it into an agricultural oasis!
The mission of the Sahara Forest Project is to turn the arid desert into a self-sustaining open greenhouse that will draw water from the atmosphere and energy from the sun. While this may sound like a far-fetched idea, advocates argue that the technologies already exist and all that needs to be done, is implement them.
The idea that has been proposed since 2008, finally became a reality last month, when Norway'sYara International ASA and the Qatar Fertilizer Company came together to provide the $5.3 million USD needed to build the pilot project.
While the Sahara desert may lack fresh water, it has plenty of access to seawater - Red Sea on the east, Atlantic Ocean on the west and the Mediterranean Sea on the north. It is therefore not surprising that salt water is the cornerstone of this project.
In order to provide the right environment for the plants, seawater will be pumped all around the greenhouse so that the hot desert air entering it will be cool and humid before it gets to the plants. This humid air which will nourish the plants as it flows along, will be collected in evaporating tubes also kept cool by seawater. This in turn, will cause the water in the collected air to condense and the fresh water droplets will be tranferred to a special storage tank and used to sustain the plants.
As the rest of the air exits the greenhouse, it will be met by protective hedges, that will keep it cool before it finally escapes into the hot desert air. This will help keep the temperature inside the greenhouse from heating up even during the day, allowing the plants to thrive.
To harness solar energy, the center is testing the use of concentrated solar power, whereby mirrors will direct the sunlight onto the water pipes and boilers. This will result in superheated steam being created inside the pipes, which in turn will power the steam turbine and help generate electricity. Any excess power produced will be distributed to the surrounding local communities.
As seems to be the case with most of our best ideas, this one too was inspired by nature - In this case the mighty camel. In order to survive in the scorching desert, the camel's nostrils are constantly condensing water from the air. The animal not only catches the moisture from the humid warm air it breaths in, but also, from the moist air that it breaths out. The designers of the Sahara Greenhouse are hoping to achieve the same kind of water catching efficienty for this pilot project.
Construction of the 10,000-square-foot greenhouse will begin in Qatar within a few weeks. If all goes well it should be ready by November 2012, just in time for the United Nations Climate Change conference scheduled to be held in Doha, at the end of the year. If the project is successful, it will be replicated across the desert, which would not only help reverse climate change, but also, provide much needed fresh produce, for the surrounding African countries.
Resources: news.nationalgeographic.com, wired.co.uk, dailymail.co.uk