Hydrogen advocates have proposed that we consider using hydrogen pipelines to wheel renewable energy long distances in lieu of high-voltage direct current (HVDC) high-voltage alternating current (HVAC). Is that idea feasible, and how might such a scheme compare in cost and efficiencies with electrical transmission lines?

The US has about 1,600 miles of hydrogen pipeline today, mostly along the Gulf Coast to service oil refiner hydrogen demand. Low concentrations of hydrogen can be mixed in the existing natural gas pipeline system for transport, and existing gas pipelines may be able...