HOT IDEAS

Some facts

1. The Peltier–Seebeck effect, or thermoelectric effect, is the direct conversion of thermal differentials to electric voltage and vice versa.
Related effects are the Thomson effect and Joule heating. The Peltier–Seebeck and Thomson effects are reversible (in fact, the Peltier and Seebeck effects are reversals of one another); Joule heating cannot be reversible under the laws of thermodynamics.

2. A voltage exists between two ends of a metal bar when a temperature difference exists in the bar.

3. A compass needle is deflected when a closed loop is formed of two metals with a temperature difference between the junctions. The metals respond differently to the temperature difference, which creates a current loop, which produces a magnetic field.

4. There's a lot of water in the air. It rises to a height of almost 100km. You feel it in high humidity, but there's almost as much invisible moisture in the air above the Sahara or the Nullarbor as there is in the steamy tropics.



Whisson Windmill

The water that pools beneath an air-conditioned car, or in the tray under an old fridge, demonstrates the principle: cool the air and you get water. And no matter how much water we might take from the air, we'd never run out. Because the oceans would immediately replace it.

Using the sun and the wind to extract water from the air