This April 2021 paper, part of the work by Columbia University’s Center on Global Energy Policy on natural gas and the energy transition, examines projections of continued natural gas use and the zero-carbon fuels that are poised to become a bigger part of the energy mix. It details the state of the existing US natural gas pipeline network and trends within this segment of the market, as well as technical considerations for moving new, zero-carbon fuels through the system. The findings, combined with potential net-zero goals, lead to recommendations for curbing greenhouse gas emissions caused by leakage in the existing network, as well as opportunities to refurbish sections to carry increasing levels of cleaner fuels. It focuses on policy options that will minimize environmental impacts and maximize economic benefits.
Specific recommendations include the following:
- Accelerate the pace to replace remaining cast-iron pipelines—which constitute a small percentage of the existing infrastructure but are responsible for an outsized percentage of methane leaks and are also incompatible with transporting hydrogen—and mandate replacement of aging pipelines.
- Adopt state-level methane reduction targets for gas utilities.
- Update federal pipeline standards to require annual inspections, change the criteria for which leaks need to be repaired, and require all leaks be reported.
- Conduct state-level inventories of the metallurgy in their pipeline infrastructure to identify parts most compatible with increased hydrogen usage, while questions surrounding how best to blend hydrogen and other zero-carbon fuels into the system undergo further study. Require that mains replacement programs use hydrogen-compatible plastic pipes.
- Consider specific rate add-ons that allow states to modify the system to accommodate hydrogen if those modifications can be made without an undue burden on ratepayers, especially lower income groups.