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Power Questions

Stuck on an energy question?

Use the list below to see the questions that we at Xcel Energy get most often from students… and their answers!
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You flip a switch to turn on the lights. You push the remote to turn on the TV. Your food is kept cold and your house is kept warm. Electricity has become an essential part of our lives, but have you ever thought about where it comes from?

When a magnetic field is moved by a wire, an electrical force is created. Xcel Energy provides its customers with electrical energy by spinning a magnet, which weighs up to 80 tons, inside a coil of wire. This is called a generator.

We usually use high temperature and high pressure steam flowing across turbine blades to make the generator spin. A variety of energy sources is used to create the steam, such as coal, uranium and natural gas. Xcel Energy also uses wind and flowing water to turn the turbine blades at our wind generators and our hydro plants.

So how does the electricity produced in a power plant get from the generator to your home?

When electricity leaves the generating plant it first goes through a transformer. In the transformer, the electrical pressure, or voltage, is raised so it can travel long distances. It then goes through miles of wire, called transmission lines, to a substation. At the substation, a transformer lowers the electrical voltage to allow easier handling in your neighborhood. Distribution lines then carry the electrical power to a transformer near your house that lowers the voltage even more, so it can easily enter your home. Finally, wires in the walls of your home carry the electricity into your outlets. All you have to do now is just flip the switch.

That depends on a lot of things. How big is your house? How many people live there? Is it well-insulated? How warm do you keep it in the winter, and how cool in the summer? The energy habits of the occupants make a huge difference in the energy consumption of a house.

But in general, a typical Xcel Energy customer’s home uses between 750- and 1,000- kilowatt hours of electricity a month. To see the amount of energy your family uses every month, ask your parents to look at your energy bill. Energy use will vary from month to month, depending on external temperature and other factors.

Nonrenewable resources like coal, natural gas and uranium are used to make electricity. They are called nonrenewable because when they are used up, there is no more on the planet; they are gone. You can read more about nonrenewable resources in the “Fossil Fuels” information sheet in the Power Sources section of this Web site.

When used to generate electricity, all of the resources including renewable resources produce byproducts.

A product is the thing you are trying to produce. A byproduct is something else that you end up with as a result. For example, a light bulb is designed to produce light, but it also produces heat as a byproduct. When coal or other fossil fuels are used to produce electricity, we also can get byproducts. Burning fossil fuels can produce gases, such as carbon dioxide (CO2), carbon monoxide (CO), sulfur dioxide (SO2) and nitrogen oxide (NOx), as well as particulate or ash, and trace amounts of metals, like mercury.

Xcel Energy and other utilities work hard to minimize the undesirable byproducts and pollution with special equipment and other measures.

Nonrenewable resources typically are less expensive than renewable resources. To see a comparison of the cost of various energy sources, as please refer to the “Power Profile” information sheet in the Power Sources section of this Web site.

Most of the coal Xcel Energy uses comes from Wyoming. Most of the natural gas we use comes from the Rocky Mountains, Texas and Canada.

Once the natural resources are used up, the land can still be used, but the resource is gone.

Electricity is fed into the energy grid from many kinds of power plants, including wind farms. But it’s like streams flowing into a river; it’s impossible to separate out the water from one stream. What customers of Xcel Energy can do is subscribe to Windsource®, one of the nation’s largest voluntary renewable energy programs. Customers who sign up pay a few dollars more a month to support the cost of developing renewable energy resources like wind and sun, and a cleaner, healthier environment.