Hydrogen Fuel's Compatibility with Existing Natural Gas Pipelines Unveiled

Strategic Insights -

Researchers at the Department of Energy's Pacific Northwest National Laboratory have been investigating the compatibility of hydrogen fuel with the existing natural gas pipeline network in the United States. The extensive network of pipelines, built and maintained over the course of a century, presents an enticing opportunity for hydrogen fuel to leverage this existing infrastructure. However, the differences between hydrogen and natural gas molecules raise concerns about their behavior in pipelines over time.

Hydrogen fuel, which can be cooled to a liquid form, may seem like an ideal candidate to utilize the same pipelines as natural gas. However, the researchers discovered that hydrogen behaves differently in pipelines due to its distinct molecular structure. This discrepancy could impact the long-term performance of the materials used in the pipelines. The scientists have also been studying blends of hydrogen and natural gas, which could potentially reduce costs for consumers while utilizing existing infrastructure.

The researchers have been testing various materials, including medium-density polyethylene (MDPE) and high-density polyethylene (HDPE), commonly used in natural gas infrastructure. These materials have not yet been used for hydrogen distribution, and their compatibility is still unknown. The team is also examining how different compositions of polyethylene respond to hydrogen fuel.

Key Takeaways:

  • Polyethylene is not a single material, but rather a wide array of different compositions, each with unique characteristics.
  • The researchers discovered that the time it took to depressurize the test piping affected a key measurement, crystallinity, which can correlate to material brittleness.
  • Hydrogen fuel was found to have both positive and negative effects on the materials used in natural gas pipelines, depending on the composition and the specific mixture of hydrogen and natural gas.
  • The results suggest that some materials may need to be replaced more frequently when used with hydrogen fuel.
  • The study used advanced cryogenic testing and pressurized solid-state nuclear magnetic resonance to observe changes in the material structure at the molecular level.
  • The work has the potential to inform the development of new infrastructure for hydrogen fuel and could help drive down costs for consumers.

Statistics:

  • The United States has approximately 2.6 million miles of natural gas transmission and distribution pipelines.
  • Hydrogen fuel is a different molecule compared to natural gas, which could impact its behavior in pipelines over time.
  • The Pacific Northwest National Laboratory has a suite of materials testing and analysis tools, including advanced cryogenic testing and pressurized solid-state nuclear magnetic resonance.
  • The researchers tested hydrogen and hydrogen blends in a wide array of materials, including MDPE and HDPE.
  • The study focused on a range of common distribution pipeline polyethylene compositions.
  • Hydrogen fuel can potentially reduce costs for consumers while utilizing existing natural gas infrastructure.

Sources:

  • "Researchers explore opportunities in shared infrastructure for the two gaseous fuels" by Oliver Peckham, Pacific Northwest National Laboratory
  • "Department of Energy, Office of Energy Efficiency and Renewable Energy's Hydrogen and Fuel Cells Technologies Office"
  • "American Society of Mechanical Engineers 2024 Pressure Vessels and Piping Conference"