How Your Carbon Footprint is Calculated
Calculating your personal impact on the environment is an important step toward fighting climate change. We understand that while very useful, calculating a carbon footprint is not an exact science.
Our calculations use current data from the U.S. Census and the U.S. Energy Information Administration, as this information is understood to be unbiased and a generally accepted source. This official data is used to calculate results that are not specific to an individual household, but as the best source available to define what is typical. Your input is used to customize your individual carbon footprint calculation.
Based on data analyzed from our validated sources, the average American lives in a single home with a detached garage, drives a large car approximately 12,900 miles a year and travels via plane an average of 17.2 hours per year. The average household has 1.8 vehicles. This collective data results in a carbon footprint for the average American of 18.8 metric tons of carbon dioxide per year with one vehicle and 23.3 metric tons of carbon dioxide with a second vehicle.
The carbon calculator is supported by a database design that contains distinctive values that are assigned to each of the approximately 42,000 active zip codes in the United States. A series of analyses were run against the various data sources to determine the average (typical) values.
To calculate estimated home energy emissions, the carbon calculator adds the amount of emissions that come from your home's heating and cooling systems. Other components that contribute to the final result include: any energy conserving upgrades, conservation appliances, and luxury appliances or electronics. This data, along with the age of the home, number of rooms, square footage, and number of persons living in the household also contribute to the calculations.
The U.S. Environmental Protection Agency's official website for Energy Star products provides information on qualified products and energy savings calculators for home improvements.
The carbon calculator multiplies the entered zip code's annual average consumption of kilowatt hours (kwh) per household by a percentage that is based on what home type is selected and if there are additional locations entered. The zip code entered is multiplied by a factor to result in average carbon dioxide emissions for that area. This includes the elements of home construction such as average insulation, windows rating, etc. and local climate conditions.
The emission intensity is calculated by measuring the number of pounds of carbon dioxide emitted, from each kilowatt hour of electricity generated.
The carbon calculator also factors in characteristics from your vehicle, such as the average miles driven per year. The average American drives 12,900 miles per year. The U.S. Department of Transportation heads the Federal Highway Administration which collects and validates useful data on vehicle registrations, licenses, miles traveled, and fuel use/prices.
The calculator provides the option to add multiple vehicles to your calculation. It also takes into account local area fuel type, driving conditions, traffic patterns and more.
The carbon calculator offers the option to input your air travel hours to help get a more accurate and complete calculation of your carbon footprint. On average, Americans fly 17.2 hours per year. By entering the amount of hours you fly a year, the carbon calculator multiplies your input by a factor, which represents the average number of miles flown per hour of air travel. We then use the total climate impact of one air-passenger mile, expressed in pounds of carbon dioxide to determine the final emissions result. Other factors included are average flight routing efficiency, ground time and average fuel consumption.
Understanding Your Carbon Calculator Results
By entering your individual values into the carbon calculator, you can compare your actual carbon dioxide emissions to the emissions of other unique scenarios.
In addition, the U.S. Environmental Protection Agency has developed a calculator to estimate carbon reduction equivalencies.
For example, if you entered that your household drives three passenger vehicles per year; this alone is equivalent to:
- 1,859 gallons of gasoline consumed
- Carbon dioxide emissions from the electricity use of 2.2 homes for one year
- Carbon dioxide emissions from the energy use of 1.4 homes for one year
- Carbon dioxide emissions from 683 propane cylinders used for home barbeques
According to data from the U.S. Environmental Protection Agency, the average American lives in a single home with a detached garage, drives a large car approximately 12,900 miles a year and travels via plane an average 17.2 hours per year. From this collective data, we calculated that the average American emits 18.8 tons of CO2 per year with one vehicle and 23.3 tons of CO2 with a second vehicle. This information allows us to assume that the calculated results equal:
- 2,134 gallons of gasoline consumed
- Carbon dioxide emissions from the electricity use of 2.5 homes for one year
- Carbon dioxide emissions from the energy use of 1.7 homes for one year
- Carbon dioxide emissions from 783 propane cylinders used for home barbeques
- 2,645 gallons of gasoline consumed
- Carbon dioxide emissions from the electricity use of 3.1 homes for one year
- Carbon dioxide emissions from the energy use of 2.1 homes for one year
- Carbon dioxide emissions from 971 propane cylinders used for home barbeques