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Retrospect

Windmill power

Created in the 19th century, wind-generated electricity is expanding worldwide

Danish Wind Industry AssociationCharles Brush’s first wind power station, in 1888Danish Wind Industry Association

Wind power is growing by leaps and bounds. For many years it was seen merely as decoration on the landscape, with large windmills planted firmly in the sand, but now this type of power is becoming important in the frenetic pursuit for clean energy sources. “It’s a market that is growing worldwide at the rate of 35% a year”, says Everaldo Feitosa, director of the Brazilian Wind Power Center (CBEE – Centro Brasileiro de Energia Eólica) and a Federal University of Pernambuco researcher. “At present, to buy any type of turbine, clients must join a two-year waiting list.”

Brazil first became seriously interested in the subject in 1992, when two turbines were installed, one in the town of Olinda and the other on the island of Fernando de Noronha. The idea was to have a field laboratory for component trials, to provide input for academic studies and to feed CBEE research programs. The two turbines were financed by the Ministry of Science and Technology, the Ministry of the Environment, the Projects and Studies Financer (Financiadora de Estudos e Projetos) and the National Electric Energy Agency (ANEEL – Agência Nacional de Energia Elétrica).

The Olinda turbine was the first large one to be connected to the power grid.  The one on Fernando de Noronha  generates some 10% of the electricity on the island, which has a population of three thousand. Now, wind power stations are found in the states of Ceará, Rio Grande do Norte, Rio Grande do Sul, Paraná, Santa Catarina and Minas Gerais, in addition to Pernambuco. The Institutional Infrastructure Program for Research and Post-graduate Studies (ProInfra – Programa Institucional de Infra-estrutura para Pesquisa e Pós-graduação) estimated in 2002 that by the end of 2008 there would be capacity of 1,423 MW , representing a total investment of US$ 1.5 billion. Pressing environmental and economic factors are  creating interest in wind power, which has been used in one way or another since ancient times in order to power boats, grind  grain or pump water.

The transformation of mechanical power into electricity appeared in the 19th century. Charles Francis Brush (1849-1929), a North American inventor and one of the US power industry’s founders, built a gigantic windmill on his Cleveland property, the first ever to drive a wind-powered turbine to produce electricity. The diameter of the rotor (the rotating piece) was 17 meters and it held 144 cedar blades. The turbine was in operation for 20 years and was used to charge batteries kept in the loft of the Brush mansion. The output was a meager 12 kW.

A few years later, Poul la Cour (1846-1908), a Danish professor and inventor, showed that the ideal thing would be to have the smallest number of blades possible in order to achieve greater efficiency and to propel the turbine. The first wind tunnel was his creation and he tested many types of turbine blades with it. La Cour also worked on models that  allowed  power to be stored and   used on windless days and also during Denmark’s long winters. He received government funding and in 1987 built his own turbine, later used in the Askov village power station. Endowed with rare social vision for his time, the inventor knew there were few workers capable of working with electricity and established the Wind Electricians Association in 1903, to train and teach people in this trade. They were taught not only how to deal with electrical machinery, but also accounting, geometry, physics and German. Because of cheap oil, these and many other wind mill experiments lasted only briefly. “But with the 1970’s crisis, Denmark, which produces no oil or gas whatsoever, strongly encouraged common people and small firms to build power stations and guaranteed the purchase of all power produced”, says Everaldo Feitosa. Today, wind power accounts for 18% of all of the energy produced within the country.

In Spain, for instance, the share of wind power is 9%; in Germany, 7%. The installed capacity worldwide is 70 thousand, sufficient for 150 thousand homes with average consumption of 100 kW a month.

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