Ten interesting things about energy

Transcription

1 Ten interesting things about energy By NASA.gov, adapted by Newsela staff on Word Count 883 Level MAX Water rushes through a dam in Georgia. Inside the dam is a hydropower plant. It uses the water's energy to generate electricity. Photo by: U.S. Army Corps of Engineers. Energy is the ability to do work. Another word for energy is "power." It is what makes things move, work and grow. Energy powers the lights in our schools and homes and fuels our cars and buses. A lot of the energy we rely on each day comes from materials dug up from deep in the earth, such as coal and oil. Today, scientists and other experts are learning more about renewable sources of energy, such as wind, water and sunlight. Here are 10 fascinating facts about energy. Always Turn Off Lights When You Leave The Room, Unless... You should always turn off the light when you leave a room, because it can save a lot of energy. But if you have special light bulbs called CFLs, you don't always have to turn them off. Turning them on and off too many times shortens their lifespans. You should turn them off if you'll be gone for 15 minutes or more, but if you'll be right back, you can leave them on. This article is available at 5 reading levels at 1

2 Coal Is King, But Not Everywhere In the United States, coal makes 39 percent of our electricity. It's burned in a power plant. The heat from burning coal is used to boil water, and then the steam moves a turbine and generates electricity. In West Virginia, over 90 percent of the electricity is generated from coal, but in California, only 1 percent of electricity is generated from this fossil fuel. Daylight Saving Time Is Good For The Planet When we turn our clocks forward each spring, we move an hour of daylight toward the end of the day. In 2008, we had four extra weeks of Daylight Saving Time. Scientists studied how much energy we saved and found out that we saved 0.5 percent of electricity. Even though that sounds small, it's actually 1.3 billion kilowatt-hours, which is about how much electricity 100,000 houses use in a whole year. Every State Uses Hydropower For Electricity A flowing river is powerful, and we can use the flow to make electricity. Ancient Greeks built water wheels to grind grain thousands of years ago. Today, every state uses hydropower, which is electricity from the flow of water. In Washington state, 70 percent of the electricity comes from hydropower. Hydropower plants are inside dams, such as the Hoover Dam. Some places don't build dams, but instead use just part of a river to make electricity. This article is available at 5 reading levels at 2

3 The United States Is A World Leader In Wind Wind has been a source of renewable energy since the invention of the windmill thousands of years ago. Today's wind power is made from big wind turbines. They're over 300 feet tall, and some have 8,000 parts! Along with China, Germany, Spain and others, the United States is using wind to make lots of electricity. The First Solar-Powered Satellite Is Still In Orbit The sun gives us lots of energy every day. It hits us with 10,000 times the world's total energy use. The space industry has used solar power since the 1960s. It's great for spacecraft. Vanguard 1 was the first spacecraft to use solar cells. It's the oldest artificial satellite still in orbit around Earth. We Can Get Energy From Trash All that waste we flush down the toilet and put in our trashcans doesn't have to go to, well, waste! When waste breaks down, it can release methane, a natural gas that we can trap and use to make electricity. This is also helpful because methane is a greenhouse gas. If we use it, we keep it out of the atmosphere. This is great for the environment. This article is available at 5 reading levels at 3

4 Electric Vehicles Are Great, But Not Everywhere Cars that run on electricity instead of gas don't release pollution. But when you charge the car at home, where does that electricity come from? If the electricity comes from renewable sources, electric cars are great for the environment, but if you charge a car with electricity made from coal, it's not as good. The car doesn't pollute, but the power plant that charges that car does. We Need Better Batteries You might be surprised, but batteries need a lot of work. They don't store enough energy. For us to use solar power and wind power, we need to be able to store a lot of energy. That way, we can still have electricity on cloudy days with no wind. Lots of researchers are working to make better batteries that last longer and hold more energy. This article is available at 5 reading levels at 4

5 We Measure Energy In BTUs When we talk about energy, we all need to use the same unit to compare numbers. Just as we might use feet or meters to talk about length, we need a unit for energy. The standard unit of energy is called the BTU, which stands for British Thermal Unit. It's the amount of energy needed to raise the temperature of a pound of water by one degree Fahrenheit. When you burn a four-inch kitchen match, it releases about 1 BTU of energy. This article is available at 5 reading levels at 5