Effect of EMFAC revised Speed Correction Factors on HC and NOx emissions
Effect of EMFAC revised Speed Correction Factors on HC and NOx emissions supports a contractor’s modeling of older vehicles’ emissions to assess inventory changes and the need for further study.
Funder: Coordinating Research Council
Due Dates: October 30, 2026 (Intent to bid) | November 13, 2026 (Proposal)
Funding Amounts: Negotiated cost-plus fixed fee or cost reimbursement contract; approximately one year beginning January 2027
Summary: Supports modeling research on how revised EMFAC high-speed correction factors affect hydrocarbon and nitrogen oxide emissions from older vehicles.
Key Information: Contract terms assign CRC ownership of inventions, improvements, and data resulting from the work.
Description
The Coordinating Research Council (CRC) seeks a contractor for Project A-152 to assess how changes to EMFAC2025 speed correction factors affect hydrocarbon (HC) and nitrogen oxide (NOx) emissions. The study will apply high-speed factors developed for LEV II/III vehicles to older pre-LEV and LEV I vehicles, then compare emissions against the model’s default factors.
The work will quantify the magnitude and distribution of emissions changes and the share of total light-duty vehicle emissions attributable to older vehicles. Statewide modeling results must be analyzed by California county and air district. Findings will help determine whether inventory differences warrant an air-quality modeling study of ozone effects or collection of real high-speed emissions data for older vehicles.
