About two-thirds of our planet is covered with water and the seas contain 97 percent of the water on earth. Deserts take up about a third of all dry land on our planet. Meanwhile the world population is growing to 9 billion people in 2050 and water and feeding all of us will become an ever greater problem.
The Sahara Forest Project is an interesting concept which seeks to employ solar power to desalinate seawater in order to irrigate the desert. Several problems could be solved this way: clear, fresh water and food.
One issue with this idea is, however, brine. Brine is water with a high salt concentration (up to 26%, where seawater contains about 3.5% salt). The Sahara Forest Project acknowledges that returning the brine back to the sea will have a negative impact on the environment. They intend to evaporate the brine in order to harvest the salt.
There is, however, an even better idea to handle the brine issue. Seawater does not only contain “kitchen salt” (sodium-chloride) but also other minerals such as magnesium. Damian Palin is investigating to use bacteria to extract minerals from brine. Extracting minerals from seawater has some advantages to “traditional” mining.