Where does wind come from? And how can it proved fossil-fuel saving alternative energy?

Sunlight heats the air over the Earth’s land masses more quickly than it heats the air over the Earth’s oceans. The warmer air over the land then rises, and the cooler ocean air moves in to replace it. We experience that moving air as wind.

Humans have been finding ways to have wind work for them since the ancient Egyptians began adding sails to the boats they used to navigate the Nile. The Persians, and much later, the Dutch, created windmills, which made their way to America, where they powered grain and sawmills.

But, with the first worldwide oil crisis in 1973, windmills took on a new significance: they were seen as alternative energy providers.

Today’s wind machines, using a far more sophisticated technology, transform the wind’s power into alternative energy by slowing the wind as it flows over their blades, causing “lift”, which makes the blades turn. The drive shaft to which the blades are joined then turns an electricity-producing generator.

Wind farms are alternative energy facilities which produce electricity from numbers of wind machines constructed over several acres. Because wind speed increases with altitude, or in open areas, wind farms are normally located on open flatlands, cleared hilltops, or in mountain passes which funnel the wind.

And, because wind speed varies according to both geography and the time of year, the effectiveness of wind farms as alternative energy suppliers will also vary.

In the California desert, superheated summer air will rise and be replaced by cool air from the Pacific. So the desert wind farms perform most efficiently from late spring to early autumn–happily, the same period when, due to the need for air conditioning, the energy demand in the area is at its peak.

Wind is supplying enough alternative energy in the U.S. to meet the needs of 1.6 million households, triple what it supplied in 1998.

As long as the sun shines, the wind will blow. And blowing in it is a clean, and renewable, alternative energy.