The phone number your parents or guardians should call before digging in the yard.


The smallest unit of matter, consisting of a positively charged nucleus made of protons and neutrons, surrounded by orbiting electrons.


A renewable energy source that comes from recently living plants and animals, such as wood, crops, manure and even garbage.

Carbon dioxide

A colorless, odorless gas formed by burning animal or plant matter and by the act of breathing. Plants absorb carbon dioxide as part of their photosynthesis process.

Carbon emissions

Carbon monoxide

A colorless, odorless, tasteless gas. It is the number one cause of unintentional poisoning around the world. 

Charging station

Like a gas pump, but for electric vehicles (EVs). The charging station gets electricity from the grid, which it delivers to a vehicle’s battery once the vehicle is plugged in. EV owners can charge their vehicle in their garage overnight. Electric vehicle charging stations can also be found outside workplaces, grocery stores, hotels and more. The more charging stations that are added across the nation, the easier and more attractive it will be to own an electric vehicle. 
Right now, three types of chargers exist: 

  • Level 1 – 4.5 miles of range per hour of charging (22 hours from 0% to full)
  • Level 2 – 26 miles of range per hour of charging (8 hours from 0% to full)
  • Level 3 or DC Fast Charging – up to 40 miles of range for every 10 minutes of charging (45 to 60 minutes from 0% to full)

The charge time depends on the type of vehicle and the battery’s level when you plug in. 22 hours seems like a long time, but most people do not need to fully charge the battery every night. 

For people who charge at home at night, a Level 1 or 2 will do the trick. For charging on-the-go or on trips, Level 2 or DC Fast Charging are better. 

Chemical energy

Stored within bonds between molecules. Sources include natural gas, gasoline, coal, batteries and more. Even the food we eat is considered chemical energy!


A black, organic rock formed from the remains of dead plants hundreds of millions of years ago. Coal is a fossil fuel and can be used to produce electricity.

Coal became America’s go-to fuel source from the late 1800s to the early 2000s because it was plentiful and cheap. However, coal has negative side effects when it’s burned for fuel. It creates emissions of sulfur dioxide, nitrogen oxides and carbon dioxide, among others. These emissions contribute to smog, acid rain, respiratory illnesses and ultimately climate change. Today, Alliant Energy is focused on using coal more responsibly (by installing technology that captures most of the bad stuff, before it is released into the air) and, by 2050, phasing coal out entirely and using natural gas and renewable energy instead.

Community solar

An array of solar panels that produces energy for the people living near it. Nearby homes and businesses can buy a block or subscription to the solar garden and receive energy from it to cover some or all of their electricity use. 

Community solar is great for people who live in an apartment or can’t/don’t want to buy solar panels to put on their roof. They get the benefits of clean energy, without owning the system itself or having equipment at their home. 


A material such as metal or water that electricity can easily flow through.


The flow of electrically charged particles such as electrons within a conductor or circuit.


The flow of electrons from one atom to another. 

Electrical energy

Comes from tiny charged particles called electrons. A lightning bolt is one form of electrical energy. The electricity in our homes is most often made by humans at generating stations

Electric vehicle (EV)

A vehicle that runs at least partially on electricity. There are several different kinds, but they all reduce air pollution by reducing or eliminating direct exhaust emissions. They’re also cheaper to drive, because the electricity they run on is less expensive than gasoline and they require less maintenance. Learn more about EVs.

Battery electric vehicle (BEV)

Also called all-electric vehicles, they run 100% on battery technology (unlike hybrids and plug-in hybrids). They don’t use gasoline, and they have no engine. The car is plugged into an electric power source to charge the battery.

Extended-range electric vehicle (EREV)

These cars run on their battery until it gets low. Then, a gasoline engine switches on to recharge the battery. The battery can also be recharged at a charging station, and the engine accepts gasoline. 

Hybrid electric vehicle (HEV)

These vehicles combine the advantages of a gasoline engine and electric motor. The main power source for these vehicles is gasoline. They don’t plug in – instead, the battery gets charged by braking and other car functions. At low speeds the vehicle will run on electricity. When more power is needed (ie, faster speeds), the vehicle automatically switches to using the internal combustion (gas) engine.

Plug-in hybrid electric vehicle (PHEV)

These are like HEVs, but can be plugged in to an electric power source to charge the on-board battery. Plus, it runs on electricity for up to 50 miles before the gas-powered engine kicks in and the car runs on the gas in its tank. 


A subatomic particle with a negative electric charge. Electrons make up part of an atom and orbit its nucleus.

Electric current


The ability to organize or change matter (to do work).

Energy audit

Also called an “energy assessment,” this is a meeting with an energy expert who inspects your home or business to find ways you can save energy.

Energy conservation

The act of using less energy or saving energy.

Energy efficient

A term that describes products and actions that use less energy due to advanced technology and equipment (for example, an energy-efficient air conditioner).


A designation given to a product or appliance that shows it meets tough government standards for energy efficiency. Products that have earned this designation have a special sticker on them with the ENERGY STAR® name. 

Fossil fuels

Fuels such as coal, oil and natural gas that formed from the remains of ancient plants and animals buried underground.

Generating station

A place where electricity is produced, sometimes also called a “power plant”.


A device that turns mechanical energy into electrical energy using an engine or turbine.

Geothermal energy

Heat, hot water or steam from within the Earth that is used to create electricity and for heating and cooling. Learn more about geothermal energy.

Gravitational energy

Associated with a gravitational field such as the one that surrounds the Earth. Have you ever fallen from a tree? You experienced the power of gravitational energy. Gravitational energy is the reason it’s easier to ride your bike downhill than uphill. 

The “grid”

Also called “power grid” or “electric grid.” The network that distributes electrical energy from where it’s generated (wind farms, solar arrays, generating stations) to where it’s used (homes, businesses, etc.) – all across the country. The poles, power lines and big transmission lines that you see along the road are all part of the grid. 


An odorless, colorless, highly flammable gaseous element.


Also called "hydro energy." Electricity created using energy that comes from moving water. Learn more about hydro energy.


Something that creates light when heated. An incandescent light bulb creates light when heat is passed through a filament.

Internal combustion engine

The motor that powers most conventional vehicles. Tiny amounts of gasoline are continuously mixed with air and compressed, setting off an explosion that’s turned into power to run the car. Battery electric vehicles don’t have an engine because they run on electricity alone. 

Kinetic energy

Anything that moves is using this kind of energy. Examples include running, cycling, climbing – even moving the mouse for a computer. Wind turbines capture the kinetic energy in wind and transform it into mechanical energy.

Law of Conservation of Energy

LEED certification

A designation or rating that shows how sustainably-built a building is. LEED stands for “Leadership in Energy and Environmental Design,” and it rates buildings based on how they save water and energy, reduce waste and support the health of people in the community. LEED is the most widely used green building rating system in the world. 

LED (Light Emitting Diode)

A source that produces light from electricity. LEDs use the movement of electrons through a semiconductor to produce visible light. LEDs have many advantages over traditional incandescent bulbs, including color quality, energy efficiency and durability. 

Lithium-ion battery

Powerful rechargeable batteries commonly used in smartphones, laptops – and electric vehicles! Pros: high power-to-weight ratio, hold their charge over time, can handle being used and recharged hundreds of times. Cons: Expensive to create and recycle, and will probably have to be replaced at least once in an electric vehicle's lifetime.

Mechanical energy

Stored in objects by tension. When the tension is released, motion occurs. A compressed spring contains mechanical energy. So does a stretched rubber band.


The substance that energy companies add to natural gas to give it a bad smell – like rotten eggs – so you can detect when there’s a leak. Learn more about natural gas safety.

Natural gas

A fossil fuel formed in underground pockets near petroleum. It is often used in homes to power furnaces, water heaters and stoves. It’s also an efficient fuel for generating electricity. Although it is a fossil fuel like coal, it is much cleaner: It produces about half the carbon emissions. Natural gas is a good fuel to supplement renewable energy because generating stations powered by it can ramp up or down quickly to compensate for when the sun isn’t shining or the wind isn’t blowing.

Non-renewable resource

resource that is not replaceable once it has been used. Fossil fuels such as coal and natural gas are non-renewable resources.

Nuclear energy

Energy stored in the nucleus of an atom. Atoms are invisible, but they make up the elements of the entire universe. Nuclear energy is released when atoms join together (fusion) or split (fission). The fusion reaction in the sun provides warmth and light, while the fission reaction at a nuclear power plant creates enough energy to power large cities. 


A fossil fuel that means “rock oil,” this smelly liquid is found in underground reservoirs and is also called crude oil.

Phantom energy loss

The constant draw of electricity by appliances and electronics even when they’re not being used.


The process by which green plants and some organisms use sunlight to synthesize foods from carbon dioxide and water. 

Photovoltaics (solar cells)

The process of creating energy through the conversion of sunlight into electricity through a photovoltaic (PV) cell, also called a solar cell. Solar panels are made up of photovoltaic cells. Sunlight is composed of photons, or particles of solar energy.

(Video definition coming soon!)


Often the energy-smart or energy-efficient version of a product is more expensive than the regular version. People might be tempted to buy the cheaper product, even though it costs them more in the long run by using more energy. Energy companies chip in money to help people afford the better option. That money is called a rebate. It’s an incentive to help people make the energy-smart choice. 

Renewable resources

Energy sources that can be replaced naturally, including energy from the sun, wind and water.

Regenerative braking

Remember the Law of Conversation of Energy, which says that energy is never created or destroyed? When you’re driving a car and put on the brakes, the kinetic energy that was moving your car forward turns into heat and is wasted. But for some hybrid and electric vehicles, it’s different. These cars have regenerative braking, which actually creates and stores useful energy in the car’s battery. When you hit the brakes, the electric motor driving the car switches into reverse mode and runs backwards to slow down the wheels. When that motor runs in reverse, it acts like an electric generator, producing energy that goes right onto the car’s battery. 

Smart home

A house with lighting, appliances, electronics, heating and other systems and devices set up to communicate with one another and be controlled remotely. This lets you – the owner – personalize everything exactly how you like it and in ways that make your life easier. 

Smart meter

A meter is the device that keeps track of how much energy a building uses. Because you usually pay for energy based on how much of it you consume, an accurate record is important. Historically, energy company representatives had to “read” all of the meters in person and record the usage information for each address. That’s a lot of trucks driving around and a lot of walking for the meter readers! Now, smart meters collect that information and report it digitally. This means lower costs and fewer errors. Plus, the smart meters can even alert the energy company of an outage. 

Solar energy (radiant energy)

Generated from the movement of light. Solar energy can be harnessed through photovoltaic cells to generate electricity. The U.S. generates enough electricity from solar energy to power 5.7 million average American homes! (Source: U.S. Department of Energy)

Solar panels

Solar panels are made up of photovoltaic cells, which can generate electricity from the sun.

Solar garden

A large array of solar panels that produces energy distributed to the energy grid

Sound energy

Produced when an object is made to vibrate, producing a sound. Your voice and musical instruments use sound energy.

Thermal (heat) energy

Created from moving molecules. The energy that comes from a fire is thermal energy.



Wind farm

What’s better than one wind turbine? A whole bunch of them! A wind farm is an area of land containing wind turbines that generate electricity. There may be just a few wind turbines, or hundreds of them. Because wind turbines need a lot of space, they are often located in fields on farms. The energy company pays the farmer to be able to place turbines on their land. The farmer can continue growing crops on the land between turbines.