EPA Tier 3 Certification Fuel Impacts Test Program Report

On January 11, 2018, EPA released a report entitled, "Tier 3 Certification Fuel Impacts Test Program." The test program discussed in this report was initiated to compare Tier 2 certification fuel, the fuel on which the Phase 1 and Phase 2 GHG and CAFE standards were established for light-duty and heavy duty-vehicles, with the new Tier 3 certification fuel from the Tier 3 program. The test program found an overall fuel economy reduction of 1.76% for the FTP and 2.42% for the HFET for Tier 3 compared to Tier 2 test fuel.  It also found that the overall test fleet showed a reduction in CO2 of 1.78% for the FTP and 1.02% for the HFET.  The program results will be used as a basis for test procedure adjustments to ensure consistent stringency of GHG and fuel economy standards as vehicle certification makes the transition to Tier 3 test fuel.  Additional information on the testing program is available here