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Evolution Of Wind GeneratorsHistory Windmills were first used to pump water and mill grain. The first wind generators were placed atop brick towers, or other buildings. By the 1930s they were mainly used to generate electricity on farms. The most famous make was the Jacobs Electric. Jacobs discovered and pioneered the modern three-blade, high-speed wind-turbine, with an integrated, low-speed, ungeared generator. In this period, high tensile steel was cheap, and windmills were placed atop prefabricated open steel lattice towers. The most famous application of the Jacobs wind-generator was to power the radio for the second polar year expedition to the south pole. Nearly thirty years later, during the IGY, explorers found the Jacobs windmill still turning, despite off-the-scale readings on a maximum-measuring wind-speed meter left as an experiment. In the 1940s, the U.S. had a rural electrification project that killed the natural market for wind-generated power. The techniques were almost lost. In the 1970s many people began to desire a self-sufficient life-style. Solar cells were too expensive for small-scale electrical generation, so practical people turned to windmills. At first they built ad-hoc designs using wood and automobile parts. Most people discovered that a reliable wind generator is a moderately complex engineering project, well beyond the ability of most romantics. Practical people began to search for and rebuild farm wind-generators from the 1930s. Jacobs wind generators were especially sought after. Later, in the 1980s, California provided tax rebates for ecologically harmless power. These rebates funded the first major use of wind power for utility electricity. As aesthetics and durability became more important, turbines were placed atop steel or reinforced concrete shells. Small generators are connected to the tower on the ground, then the tower is raised into position. Larger generators are hoisted into position atop the tower and there is a ladder or staircase inside the tower to allow technicians to reach and maintain the generator. Originally wind generators were built right next to where their power was needed. With the availability of long distance electric power transmission, wind generators are now often on wind farms in windy locations and huge ones are being built offshore. Since they're a renewable means of generating electricity, they are being widely deployed, but their cost is often subsidised by governments, either directly or through renewable energy credits. Much depends on the cost of alternative sources of electricity. Go to... |