Executive Summary

This report provides an overview of the trends and impacts of hydrogen blended fuels in the North American transport sector. In this context, “hydrogen blending” refers to the use of hydrogen in combination with hydrocarbon fuels in transportation. These hydrocarbon fuels include natural gas, diesel, and gasoline.

A summary of key hydrogen blending definitions is covered in the report, providing the reader with clarity around terms. The motivations for the adoption of hydrogen blending in the North American transport sector are outlined. These motivations are broadly categorized under environmental benefits and economic benefits, the former being the primary consideration for hydrogen blending in the transport sector.

An overview of the existing North American codes and standards highlights that some guidance on hydrogen blending for hydrogen-natural gas systems is present in these standards. Gaps which exist for some of these standards are provided for onboard vehicle fuel systems, as well as fuel dispensing stations.

This report concludes that gaps and needs for standardization in the field of hydrogen blended fuel for transportation include:

• Harmonization on the hydrogen volume fraction upper limit for blends with natural gas as an automotive fuel.
• Discussion on the feasibility of hydrogen volume fraction limit harmonization between values set by transmission and distribution system operators, and the transportation fuel set by the transport sector.
• Harmonization on the hydrogen volume fraction limit in natural gas, below which system vehicle part design does not differ from the design for natural gas powered vehicles. A similar threshold covering vehicle components and piping, as well as dispensing station fuel delivery infrastructure, is recommended for consideration.
• Inclusion of requirements for hydrogen blended fuels in standards covering onboard vehicle fuel systems, dispensing stations, and repair and maintenance facilities. Such standards have been adopted for either natural gas or hydrogen separately. Explicit inclusion of blends to provide clear requirements is needed.
• Standards coverage for hydrogen deblending, referring to technologies that serve to separate hydrogen from natural gas-hydrogen blends at the dispensing station. Such technology would help address the gap between hydrogen blending in natural gas distribution systems and hydrogen intolerance for legacy natural gas vehicles and dispensing stations.