Typical country in desert - area of Tenant Creek & Threeways. That huge propeller is actually deep water pump, taking the water from deep soil into huge water tank. They work on principle of underpressure & one-way water valve: as the propeller revolving in the wind, 10-40 m long steel arm moves up & down , at the end is a underpressure tank with water. Unfortunately, this system is useable only in the areas with steady wind blows, only hard applicable for Slovakia.