Glossary

For your convenience, this page contains an alphabetically organized list of terms, definitions and common acronyms used in the electric utility industry.

Term/Acronym	Definition
AS	Ancillary Services
ATC	Area Transmission Constraints
Adjusted Metered Load	Retail Load usage data that has been adjusted for UFE and transmission and/or distribution losses.
Adjustment Period	The Adjustment Period for any given Operating Hour is the time period following the close of the Day-Ahead market and extending up to each Operating Period.
Advisory	The second of four possible levels of communication issued by ERCOT in anticipation of a possible emergency condition detailed in Section 5.6.
Affiliate	An Entity who directly or indirectly owns or holds at least five percent of the voting securities of another Entity; or An Entity in a chain of successive ownership of at least five percent of the voting securities of another Entity; or An Entity that has at least five percent of its voting securities owned or controlled, directly or indirectly, by another Entity; or An Entity that has at least five percent of its voting securities owned or controlled, directly or indirectly, by an Entity who directly or indirectly owns or controls at least five percent of the voting securities of another Entity or an Entity in a chain of successive ownership of at least five percent of the voting securities of another Entity; or A person who is an officer or director of another entity or of a corporation in a chain of successive ownership of at least five percent of the voting securities of an Entity; or An Entity that actually exercises substantial influence or control over the policies and actions of another Entity; or Any other Entity determined by the PUCT to be an Affiliate.
Aggregated Retail Load Data	Adjusted Metered Load that has been aggregated as defined in Section 11.4.1, Aggregate Retail Load Data.
Agreement	Standard form Agreement executed between ERCOT and Market Participants.
Alert	The third of four possible levels of communication issued by ERCOT in anticipation of a possible emergency condition detailed in Section 5.6, Emergency and Short Supply Operation.
Alternative Dispute Resolution	Procedures, outlined in Section 20 of these Protocols, for settling disputes by means other than litigation.
Ancillary Service Obligations	See Obligations
Ancillary Service Supply	See Supply
Ancillary Services	Those services, described in Section 6, necessary to support the transmission of energy from Resources to Loads while maintaining reliable operation of transmission provider's transmission systems in accordance with Good Utility Practice.
Ancillary Services Plan	ERCOT produced plan, as described in Section 6, Ancillary Services, that identifies the types and amount of Ancillary Services necessary for each hour of the next day, or next two (2) days, to operate the ERCOT Transmission Grid reliably in accordance with Operating Guides, and which includes the allocation of types and amounts of the Ancillary Services Obligations for each QSE.
Annual Transmission Planning Report	A report prepared at least annually by ERCOT, as required by the PUCT rules, regarding the status of the ERCOT System including identification of ERCOT System existing and potential Congestion, which includes identification of current and recommended construction of Transmission Facilities.
Automatic Voltage Regulator	A device used on Generation Resources to automatically maintain a voltage set point.
Availability Plan	An hourly representation of availability of RMR, Synchronous Condenser and/or Black Start Resources submitted to ERCOT by Entities with RMR, Synchronous Condenser and/or Black Start Resources by 0600 in the Day Ahead Period.
Average Daily Usage	The ratio of the total consumption divided by the number of days the consumption covered. (ADU = Monthly kWh/# of days).