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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! Could I use an extension cord with surge protection for a microwave over the oven?

Answer: Yes, as long as you use a cord that meets or exceeds the power rating – usually shown in amps – listed on the extension cord and on the microwave or its user manual. Your extension cord should also be approved by a recognized safety certification laboratory, such as UL.

What is electricity made of?

Answer: Electricity isn’t a “thing” that is made of something the way a battery is, but rather a process. It begins with electrons that orbit the center of atoms. The electrons of some atoms – like those of copper and other metals – are only loosely attached, which allows electricity to travel through these materials easily. (Materials with loosely attached electrons are known as conductors.) When an outside force is applied, electrons can break free and get “bumped” from one atom to the next within a conductor. The resulting continuous flow of electrons from atom to atom results in electricity.

Turbine generators in electric power plants rely on this atomic process. The turbines turn electromagnets that are surrounded by heavy coils of copper wire. The moving magnets create the outside force that causes the electrons in the copper wire to move from atom to atom, generating electricity.

Can you use static electricity to charge things and appliances?

Answer: In principle, yes, you can. But it’s not very practical. Here’s why. Static electricity means an imbalance of electrical charge inside or on the surface of some material. Most materials are electrically neutral because the positive and negative charges inside their atoms balance each other out. A static charge builds up where electrons (what electricity is made of) migrate so that one area has a net positive charge and the other has a net negative one—but where there’s no way for current to flow between them. That energy, though, still has to come from somewhere. One example is the little spark that jumps from your fingers to a metal door handle if you’ve been shuffling around on carpeting. A static charge from the friction builds up on your skin and grounds itself through the handle. The famous inventor Nicola Tesla, dreaming of abundant free energy, developed a device that could capture the tiny static charge in ordinary air. It was enough to light up a small bulb. But a generator gives you a much bigger and more consistent flow of electricity—and if the generator is powered by wind or solar energy, the electricity is still basically free once the equipment is paid for.

Why does electricity go out during a storm?

Answer: There are multiple reasons why you could lose electricity during a storm. First of course is the weather. Winds, heavy snow, and ice can all cause trees or heavy branches to fall on power lines, knocking them down. Lightning could also hit power distribution equipment, or trees near it. Another cause is if a motor vehicle hits a power pole and damages or breaks it. Construction equipment like cranes and excavation machinery can also sometimes damage power poles or lines. Or, our transmission equipment—overhead and underground lines, transmission lines, and substation—can sometimes fail. Also, our equipment can be damaged by gunshot or objects thrown at it. Lastly, we occasionally need to de-energize lines in an area so that a worker can safely perform maintenance.

What do the colors of the tags mean?

Answer: I think you are referring to the colors of the flags and paint marks used to identify the locations and types of underground lines so that when digging projects are going on, these lines don’t get accidentally struck. The color most pertinent to what we teach on this site is red, which signifies electric power lines. As for the other colors, yellow is used for natural gas, oil, or steam lines; orange for communications lines; blue for drinking water lines; purple for reclaimed water lines; and green for sewer and drain lines. People use white marks to outline the areas where they want to dig, and pink for temporary survey marks. Whenever your family is planning any kind of digging project, they must call the underground locator service at 811 at least a few days before digging begins to get any possible underground lines marked.

When we rub our feet on a carpet, how does electricity appear?

Answer: In this situation we are experiencing static electricity, or the buildup of electric charges on an object. Electric charges are carried by electrons. When we shuffle our feet on the carpet, we are rubbing electrons off the carpet and onto our body. When we then touch a metal doorknob, for example, the extra electrons jump from our body to the metal, making a spark.

What do you remove from natural gas?

Answer: Before natural gas can be used as fuel, naturally occurring water vapor, carbon dioxide, and other molecules considered impurities must be removed. This is done in a treatment process called “sweetening” the gas.

What’s the best way to save electricity?

Answer: For most people, heating and cooling are the largest home energy costs, so lowering the thermostat on your heat in winter and using less air conditioning in summer are among the best ways to save energy. Other ways include line drying your clothes (because electric clothes dryers use a lot of electricity) and reducing the temperature on your water heater.

The best way for you to save electricity depends on a number of factors: where you live, your energy use habits, the age and efficiency of your appliances, and whether you have an electric or a gas heating system, clothes dryer, water heater, refrigerator, and range. Check out the Energy Saver Calculator in the Games section of this website for more ideas!

Is heat a part of electricity?

Electricity is created by the movement of electrons. When electrons move through an electrical wire or any conductor, they encounter resistance, and give off heat in the process of overcoming the resistance. So yes, heat is often a part of electricity.

How do you get electrocuted?

Answer: Death from electric shock, known as electrocution, can happen if you come in contact with electricity from any source, including a power line, electrical appliance, or power cord. Even a small amount of electricity from a string of holiday lights can kill a person! That's why it's so important to stay far away from power lines, and to learn to use electrical appliances, lights, and cords safely. (You can also be electrocuted if you are struck by lightning, so make sure you know how to stay safe during thunderstorms as well.)