@ajsadauskas
Thanks for sharing this information.
Still it seems to be more economical to use existing pipelines than new ones. Also a polymer coating is an option.

@WaterWaiver @AllNewTypeFace

https://www.energy.gov/eere/fuelcells/hydrogen-pipelines

https://www.siemens-energy.com/global/en/home/stories/repurposing-natural-gas-infrastructure-for-hydrogen.html