What do you think of when you hear the word “farm"? Animals? Vegetables? Tractors? Farmers? Would you believe there are farms without any of those things? It's true! What are we talking about? Wind farms!
A large wind farm can contain hundreds of wind turbines spread out over hundreds of miles. The land in between the turbines may be used for other purposes, such as regular agricultural farming. Some wind farms are also located offshore to take advantage of winds that blow across lakes or oceans.
Did you realize that wind energy is actually another form of solar energy? Winds are created by the combination of the rotation of the Earth, the irregular shape of the Earth's surface and the uneven heating of the atmosphere by the Sun's rays.
Wind farms are built in areas known to be especially windy on a regular basis. As the winds turn the blades of the turbines, the turbines convert the energy of the wind into mechanical power. Generators then convert the mechanical power into electricity that can be used to power homes just like other forms of energy.
If it's easier, you can think of a wind turbine as the opposite of a fan. A fan uses electricity to make wind. Wind turbines do the opposite: they use the wind to make electricity! As the wind turns the blades of a wind turbine, the blades cause a shaft to spin. The spinning shaft connects to a generator that creates electricity.
If you're wondering why scientists looked to the wind as an energy source, there are plenty of good reasons. Wind energy is free and renewable and, unlike conventional power plants, wind farms don't emit pollutants or greenhouse gases.
On the negative side, wind farms can cost a lot of money to set up. Over time, though, their cost is competitive with other types of generating systems. Unfortunately, you can't make the wind blow whenever you want it to, so wind farms can't always meet electricity needs on demand.
Over time, scientists believe new technologies, such as using batteries to store wind power for peak demand times, will make wind power even more popular. Wind power already accounts for about 3% of the United States' electricity. Experts believe wind power will account for 20% of the nation's electricity by 2030.