Have you ever flown a kite on a warm spring day? You couldn't have done it without wind. Maybe you have seen a sailboat race. It was wind power that pushed the boats across the water. Wind is the movement of air. It is energy called kinetic energy, or energy of motion. Kinetic energy actively does work. That means wind energy works for us! Sunlight is kinetic energy because it actively hea…
Energy is important to everyone. In fact, no one can survive without energy. Solar energy warms our planet and helps plants grow, and we need plants for food. Wind energy also helps plants grow through pollination. We need energy to produce electricity. Electricity powers everything from small appliances to huge industrial machines. We use electricity in our homes, schools, and …
Fossil fuels are nonrenewable energy sources. We use them faster than they can form naturally. Wind is a renewable energy. It blows day after day. The table lists global energy sources used everyday. …
People have used wind energy for thousands of years. Ancient Egyptians harnessed wind energy in sails. More than 5,000 years ago, Egyptians fitted canoe-like boats with sails and transported people and food along the Nile River. Sailing made fishing, traveling, and even fighting wars easier and more efficient. Sailing also affected global exploration. Christopher Columbus could not have made his …
Windmills may be the first wind-driven machines. They convert wind energy to mechanical energy. Historians believe people from Persia (now known as Iran) first used windmills to crush grain sometime between the sixth and eighth centuries. The windmills had several vertical poles with sails. Arranged in a circle, the sails rotated in the wind above a grinding wheel. Persians used the same windmill…
A modern wind turbine has three basic components: a rotor, a generator, and a support tower. The rotor is a system of rotating blades. The generator is a machine that converts energy to electricity. It receives kinetic energy from the blades through a shaft and gear system. The generator and other parts sit inside a housing called a nacelle. The tower, made of tubular steel, steel lattice, or con…
Wind energy has many advantages. The biggest advantage is that wind energy is green energy.. Green energy is friendly to the environment. Wind turbines do not burn fuel. Therefore, they do not release harmful emissions into the air. Of course, wind turbines need wind to generate electricity. That is one of wind energy's disadvantages. Many places in the world do not have sufficient winds t…
500-900 AD The Persians develop windmills to crush grain and pump water. Late 1100s The English develop windmills to crush grain. 1300s The Dutch develop windmills to drain water from low-lying areas. 1600s The Dutch colonize New Amsterdam (now New York City) and introduce their windmill designs to the New World. 1800s Windmills begin to dot the American Great Plains as the railroad and settlers …
efficient (uh-FISH-uhnt): working without wasting energy emissions (I-MISH-uhnz): harmful chemicals released into the air fossil fuels (FOSS-uhl fyoo-uhlz): coal, oil, or natural gas formed from the remains of prehistoric plants and animals generator (JEN-uh-ray-ter): a machine that converts energy to electricity grid (GRID): system that transmits and distributes electricity from power plants to …