Regionality establishes a geographical boundary within which both the clean hydrogen production project that the electrolyzer is relying on for energy attribute certificates (EACs) and the electrolyzer must be located. The boundary can range from anywhere—as in geographic restrictions—to the same grid, same regional transmission organization (RTO), or same interconnection node. The IRS is presently contemplating a framework that will incorporate relevant special viability in power systems dynamics and grid congestion and constraints to impose operational guardrails to ensure that clean energy resources powering electrolyzer loads are located in regions that allow for an appropriate degree of electricity deliverability.

The American electricity grid is subdivided into numerous regional grids with a limited capacity to transfer electricity between these systems. This limited interregional transfer capacity may result in increased GHG emissions by installing an additional amount of electricity generation capacity to support hydrogen production within regions. For this reason, the geographic location of additionally deployed clean electricity generation can result in major differences in attributable and consequential emissions.