In the United States, the transportation sector is the largest source of greenhouse gas emissions, responsible for one-third of all emissions. A recent blueprint from the Biden administration calls for drastic emissions reductions. It is the start of decarbonizing transportation in the U.S.
The largest source of emissions of carbon dioxide (CO2, the most common greenhouse gas) in the United States is the transportation sector. Emissions from transportation surpassed emissions from the electric power sector five years ago and now constitute two-fifths of domestic emissions from burning fossil fuels.
Most emissions in the transportation sector come from cars and trucks. According to the report “Emissions of Carbon Dioxide in the Transportation Sector” from the Congressional Budget Office, motor vehicles accounted for 83 percent of CO2 emissions from transportation in 2019. Personal vehicles—cars, light-duty trucks (including sport utility vehicles, crossover utility vehicles, minivans, and pickup trucks), and motorcycles—were responsible for 58 percent of emissions in the transportation sector in 2019. Emissions from commercial trucks and all buses accounted for 25 percent.
Together, the following modes of transportation accounted for the remaining 17 percent: air (including commercial passenger aviation, general aviation, air cargo, and military aviation), pipelines (for which fuel is burned to power compressors that keep oil and natural gas flowing at a steady rate), rail (passenger railroads, rail transit, and freight railroads), and water (including ships and boats).
Emissions from freight transportation depend on the weight of the cargo. In 2019, trucks carried 43 percent of all ton-miles; railroads, 29 percent; and pipelines and water transportation, most of the rest. Measured in terms of weight, air cargo accounted for less than 1 percent of freight transportation. CO2 emissions per ton-mile from the different modes of freight transportation vary greatly—far more than those from the different modes of passenger transportation. Per ton-mile, trucking produced more CO2 emissions, on average, than most other modes of freight transportation but far less than air cargo.
U.S. National Blueprint for Transport Decarbonization
In September 2022, four federal agencies quietly published a memorandum of understanding committing to working jointly toward a “clean, safe, accessible, equitable, and decarbonized transportation system for all,” including a strategy for decarbonizing the entire transportation sector. About four months later, in January 2023, staff for these agencies (the U.S. departments of Energy, Transportation, and Housing and Urban Development, as well as the Environmental Protection Agency) released it publicly, calling it the National Blueprint for Transportation Decarbonization.
The U.S. National Blueprint for Transportation Decarbonization outlines initiatives to nearly eliminate GHG emissions by 2050. Implementing a holistic decarbonization strategy will require coordinated actions from federal, regional, state, local, and Tribal governments; nonprofit and philanthropic organizations; and, last but not least, private industries.
Retailers partner up with their carriers
Driven by the growing movement of conscious consumerism, American retailers are already examining their sustainability practices to align with their customers’ values and purchasing power. As retailers research and analyze their Scope 3 emissions, that is where the transportation sector comes in. Retailers need to partner up with their carriers and logistics service providers to firstly measure their carbon emissions and create a baseline and, secondly, figure out how to tackle Scope 3 together and find creative solutions.
According to an article from Supply & Demand Chain Executive, reductions in emissions from transportation have been hard to receive so far. With final-mile companies are scrambling to find the financing and resources needed to replace their gas-powered fleets. Investing in electric vehicles is a massive financial undertaking, as well as managing the disposal of older, gas-powered vehicles. At present, there is no one-size-fits-all solution to the challenges that retailers, transportation providers and independent contractors face in today’s race to electrify light-duty vehicles.
As retailers and shipping partners cannot dictate which vehicles their logistics partners use, they must also look for other ways to reduce their Scope 3 emissions. Besides a shift to vehicles with lower emissions, they could look into a modal shift or optimizing the logistics network. Shifting transport activity to more efficient modes, e.g. from trucks to rail freight, or from cars to buses, rail, trams and metro, can also have an impact on total emissions. Cutting the number of trips or their length is another way to reduce emissions.