FERC Order 888 (1996) — Open Access Transmission Service (OATT) and Functional Unbundling

In Order No. 888, issued April 24, 1996 in Docket RM95-8-000, FERC established the foundational framework for open, non-discriminatory access to electric transmission systems across the United States. The Commission found that vertically integrated public utilities had used control of transmission to favor their own generation and block competitors, frustrating Congress's goal of wholesale competition under the Federal Power Act. Order 888 required every public utility that owns, controls, or operates interstate transmission facilities to offer transmission service to all eligible customers on comparable terms under a pro forma Open Access Transmission Tariff (OATT).

The order mandated functional unbundling: utilities had to separate their transmission operations from wholesale power marketing and generation functions so that transmission employees and information could not be used to give affiliates an unfair advantage. FERC defined firm and non-firm point-to-point transmission service, network integration transmission service for load-serving entities, and a core set of ancillary services that transmission customers could purchase alongside transmission. The pro forma OATT standardized terms for application, scheduling, curtailment, and billing so that a generator in one region could understand how to obtain service in another.

Order 888 also addressed stranded costs—the legitimate costs of generation and related assets that utilities argued could not be recovered if customers migrated to competitive suppliers once open access exposed them to market alternatives. FERC established a framework under which utilities could seek Commission approval for stranded cost recovery mechanisms, balancing the need to facilitate competition against concerns about shifting costs to remaining customers.

The order defined eligible customers broadly—including wholesale generators, power marketers, and load-serving entities seeking network service—and required reciprocity so utilities benefiting from open access in other regions could not deny comparable access at home. FERC preserved native-load obligations while opening paths for third-party transmission, and directed utilities to file compliance tariffs on Commission-approved timelines. The rulemaking responded to years of proceedings following the Energy Policy Act of 1992 and was issued alongside Order 889, which operationalized transparency requirements.

The order directed transmission providers to post available transfer capability and related transmission information, laying groundwork that Order 889 would operationalize through OASIS. Together, these reforms fundamentally restructured the wholesale electricity market by separating generation and transmission services and preventing utilities from favoring their own generation affiliates over competitors. Order 888 is widely regarded as the single most important FERC rulemaking in the transition from vertically integrated monopoly wholesale markets to open-access regional competition.