Hydrogen/Natural Gas (HCNG) Fuel Blends
Natural gas can be blended with hydrogen to make HCNG. Vehicles fueled with hydrogen/natural gas blends (HCNG) are an initial step toward the hydrogen-based transportation of the future. HCNG vehicles offer the potential for immediate emissions benefits, such as a reduction in nitrogen oxides (NOx) emissions. At the same time, they can pave the way for a transition to fuel cell vehicles by building early demand for hydrogen infrastructure.
The U.S. Department of Energy (DOE) supports light- and heavy-duty HCNG projects. DOE's Advanced Vehicle Testing Activity (AVTA) teamed with industry partners to construct and operate a hydrogen and compressed natural gas (CNG) generation and fueling facility in Phoenix, Arizona. The facility provides pure hydrogen, pure CNG, or HCNG blends to light-duty test vehicles that have been independently modified to operate on these fuels. For more information, visit AVTA's Hydrogen Blended Fuel Vehicles project.
DOE's Natural Gas Vehicle Technology Forum supported a project to develop heavy-duty HCNG engines and transit buses. The HCNG (20% hydrogen, 80% CNG) engines demonstrated lower emissions, including a 50% reduction in NOx, than similar engines fueled with CNG alone with no significant change in fuel efficiency. Chassis dynamometer emission testing confirmed the substantial NOx reduction due to HCNG when the engines were integrated into transit buses. For more information on the project, see the Westport Innovations Hydrogen Enriched Compressed Natural Gas Web site and the following documents:
- Development and Demonstration of Hydrogen and Compressed Natural Gas (H/CNG) Blend Transit Buses (PDF 833 KB) Download Adobe Reader.
- Program Overview: Hydrogen Enriched Compressed Natural Gas (PDF 267 KB) Download Adobe Reader.