The Rainmaker concept is a system whereby a stand-alone wind turbine is placed in rain lacking regions. This system is especially suited for such environments if also devoid of briny, brackish or polluted water bodies
A Dutch rainmaker system, literally, makes freshwater from air!
The system’s wind turbine does not drive a generator to produce electricity, as is commonly the case. Instead it drives a heat pump which is directly powered by the wind turbine’s blades. With the heat pump the water vapour in the air is condensed and collected for domestic or irrigation purposes.
Operating principle
Depending on local ambient temperatures and humidity conditions air always contains a certain amount of water. This makes it possible to make water from air almost anywhere in the world. For example, air of 20 0C and 50% RH (relative humidity) contains approximately 7 grams of water per kilogram of air whereas air of 30 0C and 50% RH contains almost 14 grams of water/1 kg of air. (1 m3 of air weighs approx. 1.3 kg).
Because the turbine forces air through a heat exchanger — where the air is cooled, condensation tak es place. When the temperature falls below its dew-point water droplets will form and will be collected in a water storage compartment.
Warm ambient air, in particular, may contain large amounts of water. Lowering the temperature of air requires relatively little energy. By doing so large volume of water becomes available by condensation and can be utilized as drinking water or irrigation water.
