Did you know that the average gasoline-powered vehicle produces roughly 4.8 metric tons of carbon dioxide per year? With more than 258 million light cars and trucks on the road today, annual light-duty vehicle emissions have grown to approximately 1.2 billion metric tons per year. Today, the transportation sector accounts for nearly one-third of the United States’ total greenhouse gas emissions. New alternative fuels and vehicle technologies that minimize transportation emissions, reduce gasoline consumption, improve energy security, and power a cleaner future of transportation will directly benefit the nation.
President Obama, the U.S. Department of Energy (DOE), and many major automotive producers propose that natural gas is a low-carbon transportation fuel that can reduce harmful greenhouse gas emissions. Currently, natural gas fuels 40,000 cars, 70,000 light trucks, and 40,000 heavy trucks in the United States, as well as 15.2 million vehicles worldwide. Although natural gas has been primarily used to fuel large commercial vehicle fleets or heavy-duty vehicles, it is increasingly being considered as a fuel for light-duty passenger vehicles.
Let’s consider three different ways the United States could leverage its inexpensive domestic natural gas as a transportation fuel:
- a compressed natural gas vehicle that uses a conventional internal combustion engine,
- a fuel cell electric vehicle, where natural gas is converted into hydrogen at a steam methane reforming plant which is then turned into electricity by the fuel cells to power the electric motor, and
- a plug-in electric vehicle that uses batteries recharged by electricity generated from natural gas power plants and powers the electric motor.
Compressed natural gas, natural gas to hydrogen, and electricity from natural gas.
A new Energy Department brochure compares the energy efficiency, greenhouse gas emissions and ranges of the three proposed natural gas passenger vehicle configurations using analysis by Argonne National Laboratory and its GREET Model (Greenhouse gases, Regulated Emissions, and Energy use in Transportation). The GREET Model allows analysts to calculate a vehicle’s life cycle emissions and energy use, incorporating all stages of fuel production, processing, transportation, and end use.
So, how far can natural gas take a car? It all depends on how we use it. Using the same amount of natural gas energy, fuel cell vehicles can travel about 255 miles, electric vehicles can travel 325 miles (with battery size determining the number of charging events needed), and internal combustion engine natural gas vehicles can travel 175 miles. Natural gas internal combustion engines provide vehicles with less range and higher life cycle greenhouse gas emissions per mile than fuel cell-powered or battery-powered vehicles. DOE continues to research alternative fuels in order to provide consumers with cutting-edge vehicle technologies that optimize fuel efficiency, greenhouse gas emissions, range, and price.
If you are interested in learning more about alternative energy vehicles such as natural gas vehicles, fuel cell electric vehicles, or hybrid and plug-in electric vehicles, visit DOE’s Alternative Fuels Data Center. To explore additional research conducted by the Office of Energy Efficiency and Renewable Energy, visit the policy and analysis publications website or the Vehicle Technologies Office website.