Greenhouses in the Desert

The very real possibility of shortages of energy and freshwater some day are prompting the development of all sorts of innovative technologies, especially in the hottest, driest regions of the world. How about this - greenhouses in the desert that produce freshwater, powered only by the sun and using only saltwater drawn from the sea?

Here’s how it would work. Concentrated solar power would produce steam to drive turbines, producing electricity for power. Evaporation of saltwater would produce cool, moist air for the greenhouse. Hotter, more humid air leaving the greenhouse would be further heated and humidified using solar energy, then cooled (by cool seawater), producing freshwater by condensation. The freshwater would be used to irrigate crops both within and outside the greenhouse, and would support a local settlement. Presumably most of the saltwater (now saltier than before) would be returned to the sea.

An 8-acre pilot project is expected to begin operations in Jordan within five years. If it works, other larger projects may follow.