Today’s Wonder of the Day was inspired by Lexie. Lexie Wonders, “What is Hydro Power?” Thanks for WONDERing with us, Lexie!
Do you ever take things for granted? For instance, think about your morning routine. When you wake up, do you flip on a light? Grab your lunch from the refrigerator? Turn on the TV until you leave for school? Most people don’t think much about these actions. They take it for granted that flipping a switch will make these things come on!
However, many things must happen for these devices to work. For starters, you need electricity flowing to the outlets and switches in your house. Without electricity, lamps, refrigerators, and TVs would be useless.
Where does your electricity come from? Some people get electricity from coal-burning power plants. Others get electricity from solar panels. Some use wind turbines. Some people even get electricity from water! This is called hydroelectricity.
Hydroelectric power is made by flowing water. If you live near a river that has dams, you might use hydroelectricity. So just how does a dam use water to make electricity?
It’s actually fairly simple. Hydroelectric and coal power plants make electricity in similar ways. Both use a machine called a turbine. They use a power source to turn the turbine’s propellers. As the turbine spins, it turns a metal shaft connected to an electric generator. This is basically a motor that produces electricity.
In the case of a hydroelectric dam, flowing water is used as the power source to turn the turbine. Hydroelectric dams have a special passageway for water. These passages are sloped downward to create a flow of falling water.
As the water falls down the passageway, it’s directed past the propellers of the turbine. The force of the flowing water turns the turbine. The turbine, in turn, spins the metal shaft in the electric generator. That makes electricity!
But why are dams necessary? Could you just build a hydroelectric plant on any river? Not exactly. Hydroelectric dams need to be on large rivers. They also need to have a large drop in elevation. Engineers then control the water flow to make electricity on demand at a specific rate.
Many people want to use electricity made by water instead of coal. That’s because it’s better for the environment. When we use coal to make electricity, we burn it. This adds to the greenhouse gases that cause climate change. Also, once coal is burned, it’s gone. On the other hand, the water used in hydroelectric dams keeps flowing. Thanks to the natural water cycle, hydroelectric power plants use a renewable energy source!
Standards: CCRA.L.3, CCRA.L.6, CCRA.R.1, CCRA.R.2, CCRA.R.4, CCRA.R.10, CCRA.SL.1