1 October 2010

The US Environmental Protection Agency (EPA) and the National Highway Traffic Safety Administration (NHTSA) issued a Notice of Intent to begin developing new standards for greenhouse gases (GHG) and fuel economy for light-duty vehicles for the 2017-2025 model years. The new standards will be applicable beyond the current federal GHG and CAFE program, adopted in April 2010, which set GHG and fuel economy requirements for model years 2012-2016.

The Notice of Intent (NOI) describes EPA and NHTSA’s initial assessment of potential scenarios for the 2017-2025 program, and outlines next steps in developing a rulemaking. The potential regulatory scenarios and the corresponding technological pathways are covered in more detail in the Interim Joint Technical Assessment Report (TAR) that was released along with the Notice of Intent. The TAR was jointly developed by the EPA, NHTSA, and the California Air Resources Board (ARB).

Scenarios from 3-6% annual increases in overall average stringency from the 2016 CO2 emission level of 250 g/mi are considered, as shown in the following table.

MY2025 GHG and MPG-Equivalent Scenarios
ScenarioCO2, g/miMPG Equivalent
3% per year19047
4% per year17351
5% per year15856
6% per year14362

The fuel economy figures in the table represent the regulatory testing results. Real-world CO2 is typically 25% higher and real-world fuel economy is typically 20% lower. Thus the 3% to 6% range evaluated in the assessment would span a range of real-world fuel economy values of approximately 37 to 50 mpg, which correspond to the regulatory test procedure values of 47 to 62, respectively.

The agencies believe that technologies to achieve the emission reduction targets are available or will become available within the necessary time frame. Four technology pathways were analyzed for each of the scenarios to show the different cost impacts of achieving different levels of stringency. The focus in the different technology pathways ranges from advanced gasoline and diesel vehicles to hybrids, plug-in hybrids, and electric vehicles. All pathways include vehicle mass reductions ranging from 15 to 30% in model year 2025, relative to 2008 vehicles.

According to the initial TAR assessment, the vehicle cost would increase by $800 to $3,500, depending on the phase-in stringency scenario and the technology pathway. However, the lifetime savings due to reduced fuel costs would range from $5,000 to over $7,000, resulting in an overall financial benefit for consumers.

EPA and NHTSA will be accepting public comments on the NOI and TAR by the end of October 2010. By November 30, 2010, the agencies expect to issue a Supplemental Notice of Intent that will describe further design elements for the program and present an updated analysis of potential stringencies for MY 2017-2025 standards for GHGs and fuel economy. EPA and NHTSA plan to issue a joint Notice of Proposed Rulemaking (NPRM) by September 30, 2011 and a Final Rulemaking by July 31, 2012.

Source: US EPA (Notice of Intent | Technical Assessment Report | Fact sheet)