Overview of the status of work on the heavy-duty hybrids amendments to GTR No. 4 for the 18th HDH informal group session.

Memorandum from the US EPA providing an overview of obstacles to US adoption of the proposed heavy-duty hybrids amendment and possible remedies to overcome these concerns. This memo addresses remaining concerns beyond those presented earlier in document HDH-16-03.

Decision tree for determining the powertrain family of a given vehicle under the proposed heavy-duty hybrids emissions and fuel consumption test procedures.

Status report on research and validation programs concerning:

• HILS Model Library
• WHVC Test Cycle
• System Work Concept
• Rated Power Determination for a Hybrid Vehicle
• Family Concept-Validity of Certification
• Validation Test Phase 2 (VTP2) Validation Results−Sub-presentations of VOLVO, MAN and IVECO
• VTP2 conclusions & discussion of further actions

ACEA proposal for defining a hybrid key function (torque split for parallel hybrids and energy management for serial hybrids) in the configuration of HILS software in the testing heavy-duty hybrid vehicles. ACEA also proposes to exclude “micro” hybrid systems (i.e., 48-v based systems) used to supplement the internal combustion engine as a means to reduce CO₂ emissions and improve fuel efficiency. The exclusion criteria would be based upon the ratio of positive electrical power to total system power (to be defined).