Safe Hydrogen-Natural Gas Blending: Research, Projects, and Addressing Gaps

Hydrogen blending into natural gas pipelines is often seen as a means to kick start progress towards reducing the carbon intensity of our fuels, while utilizing existing infrastructure, and accelerating the early growth of the Hydrogen Economy. In the United States, natural gas serves approximately 61% of the 125 million households and is supported by roughly 3 million miles of natural gas pipelines. Many of these pipelines and the end-use equipment they supply were not originally designed for handling hydrogen blends, eliciting safety concerns, such as embrittlement, gas leakage, and more. Understanding the safe limits of these existing pipelines and downstream equipment is crucial to the future success of hydrogen blending. Extensive research has been and continues to address steel embrittlement and other material compatibility issues, hydrogen leakage, and pipeline conversions. Additionally, multiple blending projects have monitored gas distribution system safety and shared safety information and the performance of customer appliances while blending. However, research gaps exist due to the novelty of hydrogen blending at scale and the enormity of existing natural gas infrastructure and equipment. For example, we are supporting a forthcoming blending project within a community with multiple 80+ year old, megawatt-scale, mixed diesel/natural gas generators. What safety protocols should be developed to operate these generators on a mixed diesel/natural gas/hydrogen blend? This talk will provide an overview of hydrogen blending safety concerns, the research and projects addressing these concerns, and present strategies being implemented to address knowledge gaps.