Grid Access and Regulation Foundations

Glossary

Cluster study

An interconnection study that evaluates a group of requests together rather than one at a time, required for generators under FERC Order No. 2023 on a first ready, first served basis.

Interconnection queue

The ordered list of requests to connect new generators, storage or large loads to the transmission system, each of which must pass engineering studies before an interconnection agreement is signed.

Large load

A single customer site with very high electricity demand, typically tens or hundreds of megawatts, such as a data center. Thresholds vary: Texas Senate Bill 6 uses 75 megawatts, while FERC's June 2026 orders proposed 50 megawatts.

Minimum demand charge

A tariff provision requiring a customer to pay for a set share of its contracted capacity regardless of actual use, as in AEP Ohio's 85 percent minimum and Dominion Energy Virginia's GS-5 class, which requires 85 percent of contracted transmission and distribution demand and 60 percent of generation demand.

Moratorium

A time-limited pause on applications, permits or approvals for a category of development, such as the one-year data center pause adopted by St. Charles, Missouri, in August 2025.

Public utility commission

The state agency that regulates retail electricity rates and utility service within a state. Its name varies, for example the Virginia State Corporation Commission or the Public Utilities Commission of Ohio.

Regional transmission organization

An independent body that operates the high-voltage transmission system and wholesale electricity market across the territories of many utilities, such as PJM Interconnection or MISO. Independent system operator is a closely related term for the same kind of organization.

Stranded cost

Investment a utility has made to serve customers that can no longer be recovered from those customers, for example because a large load leaves early, and that may shift to other ratepayers.