The energy picture for the country and the world has changed. The price of oil keeps rising, and it is becoming scarcer. Changes in the global climate, which are related to our use of fossil fuels, are happening at an alarming rate. The need for alternative energy sources has paved the way for the re-entry of the windmill to generate electricity.
Like old fashioned windmills, today’s wind machines use blades to collect the wind’s kinetic energy. Windmills work because they slow down the speed of the wind. The wind flows over the airfoil shaped blades causing lift, which causes them to turn. The blades are connected to a drive shaft that turns an electric generator to produce electricity. The most common type of wind machine is the horizontal axis type. Its blades are like airplane propellers.
A typical horizontal wind machine can stand as tall as a thirty-story building and has three blades that are each 131 feet long. The largest wind machines in the world have blades longer than a football field! Wind machines stand tall and wide to capture more wind.
Wind power plants, or wind farms as they are sometimes called, are clusters of wind machines used to produce electricity. A wind farm usually has dozens of wind machines scattered over a large area. The Alta Wind Energy Center in California has nearly 600 wind turbines that generate enough electricity to power 450,000 homes.
Wind machines generate electricity in forty-one different states. The states with the most wind production are California, Texas, Oklahoma, Iowa, and Kansas. Altogether, wind machines in 2018 generated 6.5% of the country’s electricity. That is enough electricity to power 26 million households.**
Wind energy offers a viable, economical alternative to conventional power plants in many areas of the country. Wind is clean fuel. Wind farms produce no air of water pollution because no fuel is burned. The most serious environmental drawbacks to wind machines may be their negative effect on wild bird populations and the visual impact on the landscape. To some, the blades of windmills on the horizon are an eyesore; to others, they’re a beautiful alternative to conventional power plants.