Master Definitions Supplement

Access Charge	A charge paid by all Market Participants withdrawing Energy from the ISO Controlled Grid, as set forth in Section 7.1.  The Access Charge will recover that portion of the Participating TO’s Transmission Revenue Requirement not recovered through Transmission Revenue Credits.	
Active Zone	The Zones so identified in Appendix I to the ISO Tariff.	
Actual Imbalance	A deviation between scheduled Generation and metered Generation at each UDC/ISO Controlled Grid boundary or at each Participating Generator's delivery point or a deviation between scheduled Load and metered Load at each UDC/ISO Controlled Grid boundary or ISO Control Area boundary.	
Adjustment Bid	A bid in the form of a curve defined by (i) the minimum MW output to which a Scheduling Coordinator will permit a resource (Generating Unit or Dispatchable Load) to be redispatched by the ISO; (ii) the maximum 	

	solely on the economic Dispatch of Generation.  This price will remain in effect until the ISO considers that the System Emergency has been contained and corrected.	
Affiliate	An entity, company or person that directly, or indirectly through one or more intermediaries, controls, or is controlled by, or is under common control with the subject entity, company, or person.	
AGC (Automatic Generation Control)	Generation equipment that automatically responds to signals from the ISO's EMS control in real time to control the power output of electric generators within a prescribed area in response to a change in system frequency, tieline loading, or the relation of these to each other, so as to maintain the target system frequency and/or the established interchange with other areas within the predetermined limits.	
Aggregate Final Accepted Schedules
	ISO approved aggregated Final Schedules.	

Ancillary Services	Regulation, Spinning Reserve, Non-Spinning Reserve, Replacement Reserve, Voltage Support and Black Start together with such other interconnected operation services as the ISO may develop in cooperation with Market Participants to support the transmission of Energy from Generation resources to Loads while maintaining reliable operation of the ISO Controlled Grid in accordance with Good Utility Practice.	
Ancillary Service Provider	A Participating Generator or an owner of Load who is 	

Day-Ahead Market	The forward market for Energy and Ancillary Services to be supplied during the Settlement Periods of a particular Trading Day that is conducted by the ISO, the PX and other Scheduling Coordinators and which closes with the ISO's acceptance of the Final Day-Ahead Schedule.	
Day-Ahead Schedule	A Schedule prepared by a Scheduling Coordinator or the ISO before the beginning of a Trading Day indicating the levels of Generation and Demand scheduled for each Settlement Period of that Trading Day.	
Default GMM	Pre calculated GMM based on historical Load and interchange levels.	
Delivery Point	The point where a transaction between Scheduling Coordinators is deemed to take place.  It can be either the Generation input point, a Demand Take-Out Point, or a transmission bus at some intermediate location.	
Demand	The rate at which Energy is delivered to Loads and Scheduling Points by Generation, transmission or distribution facilities.  It is the product of voltage and the in-phase component of alternating current measured in units of watts or standard multiples thereof, e.g., 1,000W=1kW, 1,000kW=1MW, etc.	

Demand Bid	A bid into the PX indicating a quantity of Energy that an Eligible Customer wishes to purchase and, if relevant, 	

	Another party to connect or disconnect electric equipment interconnected to the ISO Controlled Grid.	
Ex Post GMM	GMM that is calculated utilizing the real time Power Flow Model in accordance with Section 7.4.2.1.2.	
Ex Post Prices	The Hourly Ex Post Price or the BEEP Interval Ex Post Prices.	
Ex Post Transmission Loss	Transmission Loss that is calculated based on Ex Post GMM.	
Existing Contracts	The contracts which grant transmission service rights in existence on the ISO Operations Date (including any contracts entered into pursuant to such contracts) as may be amended in accordance with their terms or by agreement between the parties thereto from time to time.	
Existing Operating Agreement	The agreement between the ISO and an Existing Operating Entity entered into prior to the ISO Operations Date relating to the operation of a subsystem of that Existing Operating Entity.	

Existing Operating Entity	The entity which owns and operates a MSS (Metered Subsystem).	
Existing Rights	Those transmission service rights defined in Section 2.4.4.1.1 of the ISO Tariff.	
Facilities Study Agreement	An agreement between a Participating TO and either a Market Participant, Project Sponsor, or identified principal beneficiaries pursuant to which the Market 
Participants, Project Sponsor, and identified principal beneficiaries agree to reimburse the Participating TO for the cost of a Facility Study.	

In-Kind Self Provision:	A Scheduling Coordinator's provision of any portion of its Ancillary Services allocation to the ISO from specified individual resources.	
Inactive Zone	All Zones which the ISO Governing Board has determined do not have a workably competitive Generation market and as set out in Appendix I to the ISO Tariff.	
Incremental Change	The change in dollar value of a specific charge type from the Preliminary Settlement Statement to the Final Settlement Statement including any new charge types or Trading Day charges appearing for the first time on the Final Settlement Statement.	
Instructed Imbalance Energy	The real time change in Generation output or Demand (from dispatchable Generating Units, System Units, System Resources or Loads) which is instructed by the ISO to ensure that reliability of the ISO Control Area is maintained in accordance with Applicable Reliability Criteria.  Sources of Imbalance Energy include Spinning and Non-Spinning Reserves, Replacement Reserve, and Energy from other dispatchable Generating Units, System Units, System Resources or Loads that are able 	

	to respond to the ISO’s request for more or less Energy.	
Inter-Scheduling Coordinator Ancillary Service Trades	Ancillary Service transactions between Scheduling Coordinators.	
Inter-Scheduling Energy Coordinator Trades
	Energy transactions between Scheduling Coordinators. 	
Inter-Zonal Congestion
	Congestion across an Inter-Zonal Interface.	

Responsible Utility	The utility which is a party to the TCA in whose Service Area the Reliability Must-Run Unit is located or whose Service Area is contiguous to the Service Area in which a Reliability Must-Run Unit owned by an entity outside of the ISO Controlled Grid is located.	
Revenue Requirement	The revenue level required by a utility to cover expenses made on an investment, while earning a specified rate of return on the investment.	
Revised Schedule	A Schedule submitted by a Scheduling Coordinator to the ISO following receipt of the ISO's Suggested Adjusted Schedule.	
RMR Owner	The provider of services under a Reliability Must-Run Contract.	
RTG (Regional Transmission Group)	A voluntary organization approved by FERC and composed of transmission owners, transmission users, and other entities, organized to efficiently coordinate the planning, expansion and use of transmission on a regional and inter-regional basis.	
SCADA (Supervisory Control and Data Acquisition)	A computer system that allows an electric system operator to remotely monitor and control elements of an electric system.