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NEW! What is the average cost of school water and lights?

Answer: I don’t see any data compiled on the use of water and lights at schools in the U.S., but I can tell you that annual K-12 school utility expenditures in the U.S. as a whole top $10 billion. It’s hard to state an average cost per school because there are so many factors involved in determining a school’s energy and water use, including the total square footage of the school’s buildings, the efficiency of the school’s equipment, the school’s energy management practices and building use patterns, as well as variations in climate and activities on the campus.

Do you think that there is a type of energy that we don’t know about?

Answer: Considering all the types of energy that we have discovered in just the last 300 years, including the discovery of electricity in 1792 and of photovoltaic energy in 1839, I would say, yes, definitely, there are many types of energy that we don’t know exist. Fuel cells have been around for over 150 years, and today, NASA uses hydrogen fuel cells to convert hydrogen into electricity for astronauts. Just 70 years ago fusion energy was discovered, and now we are close to being able to use it for electric-power production. The first sources of energy were the sun and wind, and we’re looking at those renewable sources of energy today, albeit in more technologically advanced ways. There are endless sources of energy out there in the universe, waiting to be discovered—by YOU!

What is the best way to clean dryer vent hoses?

Answer: You are correct to be concerned about lint buildup in your clothes dryer vent, as this can become a fire hazard. In fact, failure to clean dryer vents is the leading cause of home clothes dryer fires. You’re also on target seasonally, as most home clothes dryer fires occur in the fall and winter months, peaking in January. However, while I am an Expert in electrical safety and energy science, I’m not equipped to instruct you on dryer vent hose cleaning. I recommend you consult a dryer duct cleaning service instead.

Is there a camp that you can go to learn about electricity? ’Cause if there is, can you please tell me, so I can go there to learn more about electricity? I am in love with electricity.
—Holly H.

Answer: Holly, we love electricity, too! Duke Energy sponsors several energy education centers and programs where you can learn more about electricity. You can find them here. In addition, you and your parents can find many camps and workshops online that teach about electricity through STEM (science, technology, engineering, and math). If you study about electricity in high school and college, you may decide to become an electrical engineer and have a career designing and working with electrical equipment and systems. If you do, come see us at Duke Energy. Maybe we can work together!

How many volts will it take to kill you instantly?

Answer: Carter, this is a tough question with no simple answer. The effects of an electrical shock vary tremendously, and whether a shock will kill someone—or merely injure them—depends upon many factors: the voltage, the amperage, how long someone is in contact with the source of the electricity, where electricity enters the body, and where a person is standing, to name just a few. Even the low-voltage electricity that you use in your home can be deadly to contact under certain circumstances. You can learn more about the effects of electrical shock in the How Electricity Can Hurt You section of this website, here.

How did Benjamin Franklin get electricity in the jar?

Answer: Franklin’s kite twine was gathering small charges of static electricity from the air. In a letter he wrote on October 19, 1752, describing directions for his kite experiment, Benjamin Franklin said: “When rain has wet the kite twine so that it can conduct the electric fire freely, you will find it streams out plentifully from the key at the approach of your knuckle, and with this key a phial, or Leyden jar, may be charged.” (Electric fire is what Franklin called electricity.) This was a very dangerous experiment, and some people who tried to copy it were electrocuted when their kites were struck by lighting. Remember: NEVER, EVER fly your kite in a lightning storm!

How was electricity invented?

Answer: Electricity wasn’t invented. It has been part of the natural world from the beginning of time in the form of static electricity, lightning, and even electric eels! Many people contributed to the discovery of electricity and how it works, including English physicist William Brown, American Benjamin Franklin, Italian Luigi Galvani, and many others around the world. Many more people have invented the equipment that allows us to use electricity safely, such as Alessandro Volta’s battery, Michael Faraday’s electric motor, and Thomas Edison’s light bulb, to name a very few. You can learn more about these and other electricity pioneers here.

How do so many people use electricity at the same time???

Answer: It’s mind-boggling when you think about it, isn’t it? Our electricity comes from hundreds of big electric power plants all over the country that are powered by coal, oil, natural gas and nuclear energy, along with smaller generation facilities powered by wind, water, solar, biomass and geothermal energy. Together these power plants generate hundreds of millions of watts of electricity, and they do it constantly, night and day.

The power plants are all connected together in a system called the electrical grid. Utility companies, the companies that distribute electricity to homes and businesses in their regions, work together to ensure that electric power flows wherever it is needed across this grid. Utilities that are generating more power than their customers need at the moment pass it to other utilities that aren’t generating quite enough. That’s how so many millions of us get to use electricity at once.

Is there a location people can go to learn how energy moves?

Answer: You’re in luck, Holly! Duke Energy sponsors quite a few energy education centers and programs that you can participate in to deepen your learning about how energy works. Learn more about them here.

I was wondering if someone can explain how a Shock Pen works. I opened one up and did some research. From what I understand, there is a battery supply and an induction coil. I don't understand how this setup works, or what it needs to work properly.

Answer: A safe shock pen has three essential components: one or more batteries (usually AAA); an induction coil that serves as a transformer of the current from the battery; and a device, usually a transistor, that causes the current to switch on and off very rapidly. The induction coil (a much smaller version of the spark coils used in auto ignition systems) converts the output from the battery to a much higher voltage by way of electromagnetic induction. Basically, the current from the battery creates an electromagnetic field in the coil, which stores its energy. When the current is interrupted by the transistor (think of it as a tiny switch), the magnetic field in the coil abruptly collapses. That sends a pulse of electric current into the circuit—which is what causes the shock. The transistor flips again and the process repeats itself. This happens many times a second for as long as the circuit is open and current is flowing. In the case of the pen, the circuit only stays open for as long as the person holding it is holding down the “clicker.”


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