The renewable energy sources, derived principally from the enormous power of the sun’s radiation, are at once the most ancient and the most modern forms of energy used by humanity.

The earth’s wind systems are due to the movement of atmospheric air masses as a result of variations in atmospheric pressure, which in turn are the result of differences in the solar heating of different parts of the earth’s surface.

Wind can be used to do work.  In fact, wind energy was one of the first non-animal sources of energy to be exploited by early civilisations and it is thought that wind was first used to propel sailing boats. The energy of the wind can be changed into other forms of energy, either mechanical or electrical energy. When a boat lifts a sail, it is using wind energy to push it through the water. This is one form of mechanical work.
Similarly, in Holland, windmills have been used for centuries to pump water from low-lying areas.

Wind is also used to turn large grinding stones to grind wheat or corn, just like a water wheel is turned by water power. Today, there are several hundred thousand windmills in operation around the world, many of which are used for water pumping. Until recently, many of them used to dot the Maltese countryside too, though in the past few years they have given way to electrical pumps thanks to cheap subsidised electricity.

But it is the use of wind energy as a pollution-free means of generating electricity on a significant scale that is attracting most current interest in the subject. Strictly speaking, a windmill is used for milling grain; hence modern wind mills are referred to as wind turbines, simply because like other types of turbines they are used to generate electricity.

Attempts to generate electricity from wind energy have been made since the end of the nineteenth century. Small wind machines for charging batteries have been manufactured since the 1930s.It is only recently that the technology has become sufficiently mature to enable a viable large-scale industry to evolve, mainly in the form of large turbines for electricity production.

This has resulted in wind becoming one of the most cost-effective methods of electricity generation available. The technology is continually being improved to make it both cheaper and more reliable, so it can be expected that wind energy will become even more economically competitive over the coming decades.