In many regions where briny or brackish water is found this type of wind turbine will provide an answer to the problem. Beside the ability to make clean drinking water, its use of sustainable energy ensures that the environment will not become more overburdened and, important for the user, that energy costs will be independent of the supply-and-demand whims of energy markets. 

The diagram shows how the evaporator and condenser are used. Water that evaporated under low pressure by means of a heat pump condenses again and returns heat to the evaporator. This system makes it possible to desalinate large quantities of water with little energy. Expected yield is approximately 60 m3 a day for the first products developed.


The characteristics for the first water-to-water products are:

Technical specifications ‘Water-to-water’
Comparable traditional windmill capacity: 100 [kW]
At wind speed: 13 [m/s]
Rotor diameter: 18-21 [m]
Footprint: 400 [m²]
No. of blades: 3
Start wind: 2,5 [m/s]
Tower height: 35-45 [m]
Weight: 25 [ton]

The Air-to-water 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.

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.

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 takes 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.

Technical specifications ‘Air-to-water’

Comparable traditional windmill capacit: 100 [kW]
At wind speed: 13 [m/s]
Rotor diameter: 18-21 [m]
Footprint: 400 [m²]
No. of blades: 3
Start wind: 2,5 [m/s]
Tower height: 35-45 [m]
Weight: 25 [ton]