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Have you ever wondered why shoes hanging on a power line don’t get fried? Or why natural gas flames are blue? Or whether garbage could someday be a source of energy? Now you can get answers to these and all your energy-related questions. Just Ask an Expert!

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NEW! How is electricity created with atoms?

Answer: The movement of electrons between atoms is what generates electricity. In power plants various energy sources—such as fossil fuels (coal, oil, or natural gas) or renewable energy sources (sun, wind, biomass, geothermal, or hydropower)—are used to turn turbines. The turbines turn electromagnets that are surrounded by heavy coils of copper wire. The moving magnets then cause the electrons in the copper wire to move from atom to atom, generating electricity.

What is an electromagnet?

Answer: An electromagnet is a magnet in which the magnetic field is produced by a flow of electric current. It consists of a coil of copper wire wrapped around an iron core. You can change (or stop) the strength of an electromagnet by adjusting the amount of electricity flowing through it.

How does planting trees save energy?

Answer: Trees planted on the south and west sides of your home will keep your house cooler in the summer because the shade they provide screens the sun’s rays from hitting your house and heating it up. This means you won’t have to make your air conditioning work quite so hard, thus saving energy. And planting evergreen trees and shrubs on the north and northwest sides of your home can lessen the impact of cold winter winds, while still allowing warmth from the sun to hit the house. You can save energy and money by reducing the amount of heating required to keep your house comfortable.

Why do we have to stay away from power lines?

Answer: Power lines carry electricity. If you touch a power line with a part of your body, or even with something you are holding like a kite or a ladder, electricity will leave the power line and flow through you, giving you a serious electric shock. You could be badly burned or even killed! Always play far away from power lines and never touch one with your hand or with any other object.

I once saw a pair of shoes hanging from a power line. Why didn’t the shoes get burned up by the electricity in the line?

Answer: Shoes hanging on a power line don’t get burned for the same reason that birds standing on a power line don’t get shocked: they don’t give electricity a path to the ground, so electricity stays in the line and does not go through them. But if the shoes were to touch a power line and a power pole at the same time, they would provide a path to the ground and would get blasted with electric current. It wouldn’t be pretty! By the way, if you ever see someone throwing shoes up onto a line, tell them to stop! The shoes can damage the power line, or someone trying to get the shoes down could be seriously shocked or even killed.

Why does the flame on my stove burners look blue, but the flame of a campfire is yellow?

Answer: A natural gas flame burns hotter than a campfire. In general, cooler flames appear yellow, orange, or red, while hotter flames look blue or white. (While flecks of orange in your gas flames are okay, if the flame is yellow, large, and flickering, the appliance may need a safety adjustment by a qualified repair person.)

I have heard that landfills can be a source of energy. How does that work?

Answer: Just like manure, other types of organic waste emit methane as they decompose —or rot—in the landfill. Landfills can collect and treat the methane, and then sell it as a commercial fuel; or they can burn it to generate steam and electricity. Today, there are almost 400 gas energy landfill projects operating in the United States.

Do electric eels really create electricity?

Answer: Yes! An electric eel uses chemicals in its body to manufacture electricity. A large electric eel can produce a charge of up to 650 volts, which is more than five times the shocking power of a household outlet.

Who discovered natural gas?

Answer: The ancient Chinese were the first to discover underground deposits of natural gas. In 600 BC, Confucius wrote of wells 100 feet deep yielding water and natural gas along the Tibetan border. The Chinese piped the gas to where it was needed through long, hollow bamboo stalks.

What’s the difference between global warming and the greenhouse effect?

Answer: The greenhouse effect is created because certain gases sent into our atmosphere, such as carbon dioxide, allow radiation from the sun to pass through the earth’s atmosphere, but prevent a portion of the infrared radiation from the earth’s surface and lower atmosphere from escaping into outer space. This process occurs naturally; without it our planet’s temperatures would be about 60 degrees cooler! Life as we know it simply would not exist without the natural greenhouse effect. However, many scientists believe global warming is happening because the greenhouse effect has become intensified by human activities (primarily the burning of fossil fuels), which adds more carbon dioxide and other gases to the atmosphere and increases the warming process.

What kind of a difference does it really make to replace a regular light bulb with an energy-saving one?

Answer: Replacing one incandescent light bulb with an energy-saving compact fluorescent bulb prevents about 1,000 pounds of carbon dioxide from being emitted to the atmosphere from power plants, and saves about $67 dollars in energy costs over the bulb's lifetime.