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Have you ever wondered why shoes hanging on a power line don’t get fried? Or whether cars could someday run on cow manure? Now you can get answers to these and all your energy-related questions. Just ask an Expert!

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NEW! What types of energy do you use?

Answer: I think you mean what types of energy sources do we use, so I will answer your question as such. At our Cleary-Flood Generating Station we use a combination of many different energy sources. The ones we rely on the most are natural gas, nuclear, hydropower, and oil. We also use a significant amount of landfill, refuse, and wood energy (all of which are types of biomass energy), as well as solar and wind energy. You can read more about all these types of energy on our website’s section on Producing Electricity.

Does speed dry on an HE dryer use more energy than the regular dry setting? I know [speed dry] dries clothes in half the time; I just wanted to know if it used more energy.

Answer: I assume you are referring to "high efficiency" when you say HE dryer; however, I have not been able to identify any HE dryers commonly sold at appliance outlets. (More typically it is washers that are labeled HE.) According to Energy Star, a government program that identifies energy-efficient products, the clothes dryers on the U.S. market do not vary significantly from each other in terms of energy consumption. The best way to make a dryer more efficient is through the newer moisture-sensing technology, which automatically shuts off the machine when the clothes are dry; perhaps your dryer uses this technology. I have also not been able to locate any dryers with a speed dry feature. Perhaps you could let me know your model so that I could research this further.

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.

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.

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.

Is it true that cars could someday run on cow manure?

Answer: Yes! Manure can be made into a gas containing methane. (Methane is the same energy-rich gas found in natural gas.) Certain types of bacteria emit this gas as they consume manure collected in special air-free tanks. The mixture of gases produced in this way, called biogas, can then be used in some modified car engines instead of gasoline, or burned in a boiler to generate heat or electricity.

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.

How much energy is in a bolt of lightning?

Answer: One lightning strike can carry up to 30 million volts—as much electricity as 2.5 million car batteries.

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.

Why didn’t Ben Franklin get killed when he tied a metal key to a kite string and flew the kite in a thunderstorm?

Answer: Ben Franklin’s famous key did give off an electric spark. But lucky for Franklin, the kite was just drawing small electrical charges from the air. If the kite had been struck by lightning, Franklin would have been killed!