Log in | Subscribe | RSS feed

What’s New

US EPA, DOT finalize Phase 2 GHG and fuel efficiency standards for heavy-duty trucks

16 August 2016

Today the US Environmental Protection Agency (EPA) and the US Department of Transportation’s National Highway Traffic Safety Administration (NHTSA) finalized the Phase 2 GHG and fuel efficiency standards for medium- and heavy-duty vehicles. The adopted Phase 2 rule will be phased-in over the period of 2021-2027, following the current Phase 1 GHG and fuel efficiency regulations that are being phased-in over the period of 2014-2018. The Phase 2 GHG rule was proposed in June 2015.

The adopted standards apply to semi-trucks, large pickup trucks and vans, and all types and sizes of buses and work trucks. The regulations maintain separate CO2 and fuel efficiency performance standards for complete vehicles and for engines. The engine compliance is determined through engine dynamometer testing, while vehicle compliance is determined using the GEM computer simulation developed by the EPA.

The Phase 2 regulation also includes efficiency and GHG standards for trailers, which were not included in the Phase 1 standards. The EPA trailer standards, which exclude certain categories such as mobile homes, will begin to take effect in model year 2018 for certain trailers, while NHTSA’s standards will take effect as of 2021, with credits available for voluntary participation before then. The fuel efficiency technologies expected to be used in trailers include aerodynamic devices, light weight construction and self-inflating tires. When the standards are fully phased in, tractors in a tractor-trailer will achieve up to 25% lower CO2 emissions and fuel consumption than an equivalent tractor in 2018.

The final standards are cost effective for consumers and businesses, delivering favorable payback periods for truck owners, according to the EPA. The buyer of a new long-haul truck in 2027 would recoup the investment in fuel-efficient technology in less than two years through fuel savings.

Heavy-duty trucks currently account for about 20% of GHG emissions and oil use in the US transportation sector. Globally, GHG emissions from heavy-duty vehicles are growing rapidly and are expected to surpass emissions from passenger vehicles by 2030.

The Phase 2 rule has been tightened to some degree compared to the proposal. The final rule includes greater emphasis on advanced fuel efficiency technologies and achieves 10% more GHG and fuel consumption reductions than the proposal. In diesel engines, the final standards will reduce CO2 emissions by up to 5% for tractor engines and up to 4% for vocational engines compared to 2018 engines (up from the proposed 4% for all engines).

The final Phase 2 standards also include more robust compliance provisions, including improved test procedures, enhanced enforcement audits and protection against defeat devices. Among the changes, a revised test cycle weighting for tractor engines has been adopted to better reflect actual in-use operation.

NHTSA and EPA have worked together to harmonize their standards under this program. The agencies have worked closely with the State of California’s Air Resources Board (ARB) in developing and finalizing the standards. All three agencies are committed to the goal of setting harmonized national standards. Throughout every stage of development, this work has benefited from a collaborative dialogue with industry, labor and environmental organizations. For example, this feedback has improved the agencies’ ability to measure industry performance and enforce compliance for both full vehicle and engine standards.

In its comments on the Phase 2 proposal, the California ARB called for strengthening the GHG emission requirements and threatened to adopt their own GHG standards, going beyond the federal Phase 2 requirements. The ARB had also expected that the Phase 2 GHG rule would include a commitment by the EPA to begin development of stricter NOx emission standards for heavy-duty diesel engines.

In a statement on the final Phase 2 rule issued today, the California ARB expressed its support of the new federal standards. However, the agency also said that California will need to continue to make progress in GHG emission reduction, even after the Phase 2 standards are fully implemented in 2027. The ARB is looking forward to continued cooperation with the federal agencies on this long-term effort.

The ARB also renewed their call on the EPA to develop new, low NOx emission standards for heavy-duty engines. “CARB is looking forward to working with the federal agencies to develop new, lower NOx standards which are critically needed in California to clean the state’s air in time to meet federal Clean Air Act deadlines. In order to achieve the 2008 Ozone National Ambient Air Quality Standards set by US EPA, CARB estimates that the South Coast Air Basin alone (including Los Angeles) will need an 80 percent reduction in NOx emissions by 2031,” said the agency. The ARB emphasized that federal low NOx standards would be more effective than California-only standards, because many trucks operating in California are first purchased outside the state. In addition, 60% of total heavy-duty truck miles in Southern California are driven by trucks purchased outside of California. The ARB has been targeting a heavy-duty engine NOx standard of 0.02 g/bhp-hr, a 90% reduction from the current limit of 0.2 g/bhp-hr.