In Oman, as in many parts of the world, desalination is the only method of meeting the shortfall. Yet desalination is expensive in terms of energy. Even with the more efficient desalination plant, 1 kg of oil can only yield about 1000 kg of freshwater. Using standard methods of irrigation, this amount of water may only yield about 1 or 2 kg of edible crop (see Figure 1 below).