Vehicle Emissions Calculator

CO2 Emissions from Cars

This calculator can be used to estimate the greenhouse gas emissions, specifically carbon dioxide, produced by a car each year. The calculator accepts both Imperial and Metric units of measurement. The calculator requires only two inputs:

  • An estimate of the number of miles, or kilometers, driven each year
  • The fuel efficiency of the vehicle, stated in either miles per gallon (MPG) or liters per 100 kilometers

The calculator then provides the user with three annual values:

  • The gallons / liters of gasoline / petrol consumed
  • The pounds / kilograms of CO2 produced
  • The acres of forest required to remove the CO2

Greenhouse Gas Emissions

Gases that can trap heat in the earth’s atmosphere are known as greenhouse gases. The most common of these include carbon dioxide, methane, nitrous oxide, and a variety of fluorinated gases such as hydrofluorocarbons.

Carbon dioxide (CO2) is the primary greenhouse gas attributed to human activities, making up around 80% of the annual total.

While carbon dioxide enters the atmosphere through the burning of fossil fuels such as gasoline or petrol, it can also be captured, or sequestered, when it is absorbed by plants.

greenhouse gas chart
Source: United States Environmental Protection Agency

Lowering Your Carbon Footprint

While it is interesting to know how many acres of forest are needed to absorb the CO2 your car produces each year, it’s unreasonable to expect someone to purchase land and plant enough trees to capture the greenhouse gases their car produces. The calculator does provide insights into how we can lower our carbon footprint. The most obvious way is to drive fewer miles each year. For example, if 80% of the miles driven are commuting to and from your place of business, then working from home two to three days a week can lower the greenhouse gases produced by your car by 32 to 48%.

You can also lower your carbon footprint by choosing a more environmentally friendly vehicle for your commute to work. According to the U.S. Department of Energy, the average light truck gets around 17 miles per gallon of gasoline (13.8 liters or petrol per 100km), while the average car gets just over 24 miles per gallon (9.8 liters or petrol per 100km). The difference between 17 and 24 miles per gallon might not seem large, but the result is a nearly 30% decrease in greenhouse gas emissions.