On June 19, the U.S. Environmental Protection Agency (EPA) and the Department of Transportation’s National Highway Traffic Safety Administration (NHTSA) announced major increases for fuel efficiency of heavy-duty trucks. Part of President Obama’s comprehensive Climate Action Plan, Phase 2 of the Heavy-Duty National Program tightens emission standards for heavy-duty trucks and includes big rigs, delivery vehicles, dump trucks and buses.  The updated efficiency rule for trucks joins a growing list of fuel efficiency measures, including the President’s 2012 doubling of fuel efficiency standards for cars and light-duty trucks (CAFE standards), as well as expected aircraft rules, following the agency’s finding that aircraft emissions endanger human health.

While the miles per gallon (mpg) rating of cars and light duty trucks has increased over the last decade or so, the fuel efficiency of heavy-duty trucks has held at 5 mpg for over four decades. Conversely, the average passenger vehicle reached 24 mpg in 2010.  Under CAFE, cars and light duty trucks are set to reach 54.5 MPG by 2025. 

According to EPA, heavy-duty trucks are the fastest growing emissions segment of the U.S. transportation sector; they are currently responsible for 20 percent of greenhouse gas (GHG) emissions, while comprising just 4 percent of on-road vehicles.  Heavy duty trucks power the consumer economy, carrying 70 percent of all U.S. freight – weighing in at 10 billion tons of everything from food to electronics, building materials, clothes and other consumer goods.

Phase 2 of the rules will apply to model year trucks between 2021 and 2027, when new standards are expected to be set. Between 2021 and 2027, EPA calculates that oil use will be cut by 24 percent, or 1.8 billion barrels.  Increased efficiency in heavy-duty trucks will save $170 billion in fuel for businesses and drivers. While the improvements are expected to cost up to $12,000 per vehicle, EPA estimates that costs would be recouped in as little as two years through fuel savings. Additionally, GHGs would be cut by one billion metric tons.

The trucking industry has been relatively open to adopting technology that will save on fuel costs, which stands in contrast to industry reaction to other EPA regulations that seek to cut carbon emissions. The Clean Power Plan, which cuts GHGs from the power sector, has spurred lawsuits from states and industry. Ahead of the Phase 2 announcement, the trucking industry was cautiously optimistic that the administration would adopt achievable standards. This is perhaps because of the steep cost of fuel to the industry; fuel costs are the second largest cost of the trucking industry.  

While environmental groups had asked the administration for efficiency improvements up to 40 percent, by 2027, Phase 2 of the regulations will achieve:

  • A 24 percent reduction in CO2 emissions and fuel use for combination tractors (18 wheeler or big rig) compared to Phase 1.
  • An 8 percent reduction for trailers as compared to 2017.
  • A 16 percent reduction for vocational vehicles (ex: garbage trucks), pick-up trucks, and light vans, compared to Phase 1.

The standards are agnostic as far as solutions, but could be met with a combination of technologies and fuel solutions, including more efficient tires, improvements in truck design, and fuel switching.  Under the new rules, emissions will be quickly reduced from further improvements in energy efficiency, but to truly reduce the amount of diesel being used, fuel switching will most likely play a role in meeting deep emissions cuts.

On the fuels side, this could take a few different pathways. For example, Waste Management Inc. has switched from diesel to natural gas, providing an immediate 20 percent cut in emissions.  By capturing landfill gas and fueling portions of their fleet with this form of renewable natural gas (RNG), the company has cut emissions even further.  According to a company spokeswoman, Waste Management is capturing RNG at 262 landfills.

Biodiesel, sourced from soybean and corn oil as well as waste fats, greases and oils, can also be blended with diesel fuel to reduce diesel’s carbon intensity.  According to research from Argonne National Laboratory and the National Renewable Energy Laboratory, biodiesel reduces carbon emissions on a lifecycle basis between 56 and 88 percent compared to diesel. Reductions in emissions are deepest for biodiesel sourced from waste oils, such as recycled vegetable oil from restaurants and the food industry. Currently, all diesel vehicles can utilize a 5 percent biodiesel blend (B5), and many vehicles can utilize blends up to 20 percent (B20).

According to the American Trucking Associations’ Vice President and Energy and Environmental Council Glen Kedzie, “In 2014, trucking spent nearly $150 billion on diesel fuel alone … so the potential for real cost savings and associated environmental benefits of this rule are there – but fleets will need a wide variety of proven and durable technologies to meet these new standards throughout the various implementation stages.”



For more information see:

Biodiesel Vehicle Emissions, U.S. DOE

Obama admin set to release mandatory carbon cuts for heavy-duty vehicles, E&E News

EPA and NHTSA Propose Greenhouse Gas and Fuel Efficiency Standards for Medium- and Heavy-Duty Trucks: By the Numbers, U.S. EPA

Proposed Rule for Big Trucks Aims at Cutting Fuel Emissions, NY Times 

ATA Remains Optimistic on Truck Greenhouse Gas and Fuel Efficiency Proposal, Trucking.org