Electricity is different from other forms of energy because it merely delivers the energy harnessed from other materials, the primary energy source, at the generating facility.
Click on the tabs below to learn about electricity and its contribution to your carbon footprint.
Move a magnet through a circle of copper wire, and you get electricity. Spin giant magnets in massive coils of wire, and you generate electricity to power cities.
Spinning those magnets requires energy—energy to turn a turbine that spins the magnets in the generator. That energy might come from fossil and nuclear fuels, wind, running water, or the sun.
Fossil fuels—coal, oil, and natural gas—are the most common energy source used to make electricity: 64% in North America and 68% globally. These fuels boil water to make the steam that spins the turbines that generate electricity.1 Coal is the number one fossil fuel for electric power, followed by natural gas. Very little electricity comes from other petroleum products.2
Fossil fuels all contain carbon, so burning them makes CO2 and increases your carbon footprint. The amount of CO2 produced when a fuel is burned depends on the carbon content of that fuel. The pounds of CO2 emitted for each million Btu of energy from some fossil fuels are as follows:3
Anthracite coal 229 lbs
Bituminous coal 206 lbs
Subbituminous coal 214 lbs
Lignite 215 lbs
Natural gas 117 lbs
Propane 139 lbs
Gasoline 157 lbs
Diesel and heating fuel 161 lbs
1www.iea.org/publications/freepublications/publication/keyworld2014.pdf (accessed July 13, 2015).
2https://www.eia.gov/tools/faqs/faq.php?id=427&t=3 (accessed March 16, 2017).
3https://www.eia.gov/tools/faqs/faq.php?id=73&t=11 (accessed March 16, 2017).
Flowing water has spun turbines to generate electricity for over a century, either from dams or diversions. A change in elevation creates the flow and is the critical component to drawing energy from water to generate electricity—hydro. Using hydro to make electricity does not emit CO2. Because a stable and continuous flow of water produces a stable and continuous flow of electricity, water is a reliable source of power.1
Wind can also spin turbines, and this provides a good source of electricity when the wind is blowing (most efficiently between 25 and 35 mph1 [40 and 55 kph]). But, the wind isn’t always blowing; wind is a variable source of electricity. Electricity from wind does not emit CO2.
1energybible.com/wind_energy/wind_speed.html (accessed July 13, 2015).
Some power companies use the heat from nuclear fission to turn water into the steam that spins the turbines. Electricity generated from nuclear energy has no CO2 emissions. This type of generation produces a stable and continuous flow of electricity.
The heat from burning crop residue and wood waste can make steam to turn turbines (albeit at a smaller scale than fossil fuels). This type of generation produces a stable and continuous flow of electricity. Burning biomass creates CO2. However, the consensus is that this CO2 simply replaces the CO2 recently removed from the atmosphere as part of the ongoing natural carbon cycle.
Solar energy makes electricity in two ways. Light-sensitive panels (containing photovoltaic cells) absorb sunlight, transforming it into electricity. For large-scale power generation, acres of mirrors concentrate sunlight on a solar-heated boiler in a solar tower that makes the steam to turn turbines. Electricity from solar does not produce CO2 emissions.
Developed for the North Dakota Department of Commerce Division of Community Services with funding from the U.S. Department of Energy