Aggregator - An Aggregator refers to any entity that assembles a group of retail customers and provides or assists in providing electric power and energy supply services to that group based upon the group’s electrical usage characteristics or commercial characteristics (e.g., credit). An Aggregator may also provide other services. An Aggregator can be a Retail Electric Supplier (RES). While many (perhaps most) other aggregators will be Alternative Retail Electric Suppliers (ARESs), an electric utility can offer aggregation services outside its service territory.

Alternative Retail Electric Supplier (ARES) - An entity, other than an Illinois jurisdictional utility which sells electricity to Retail Electric Customers in Illinois. ARES must be certified by the Illinois Commerce Commission.

Ancillary Transmission Services or Ancillary Services - Ancillary Transmission Services or Ancillary Services are necessary in order for the electric transmission system to function properly. Currently, there are seven Ancillary Transmission Services: Scheduling, System Control, and Dispatch; Reactive Supply and Voltage Control from Generation Sources; Regulation and Frequency Response; Energy Imbalance; Operating Reserve – Spinning Reserve; Operating Reserve – Supplemental Reserve, and Black Start Service.

Available Transfer Capability (ATC) - The amount of energy above “base conditions” that can be transferred reliably from one area to another over all transmission facilities without violating any pre- or post-contingency criteria for the facilities in the PJM Control Area under specified system conditions.

Billing Determinant - An item or a group of items from the billing and meter reading systems mainly focused on usage. These measurements are used in the calculation of both the delivery services and the energy bills.

ComEd Zone - The Northern Illinois Control Area (NICA) within the PJM footprint.

Control Area Operator - The entity whose role is to balance generation resources and load in order to maintain frequency and reliability.

Customer Self-Manager (CSM) - A retail electric customer that directly manages its own supply of electric power and energy rather than using a Retail Electric Supplier for that purpose. The Customer Self-Manager must meet all the requirements in Rate RCDS and in its Customer Self-Manager Contract with ComEd.

Data Requests - Requests that come from customers, customer agents, Metering Service Providers or from Retail Electric Suppliers, with customer authorization, to the utility for customer-specific historical billing and usage data.

Delivery Services - This term is defined by Section 16-102 of the Public Utilities Act as follows: "Delivery Services" means those services provided by the electric utility that are necessary in order for the transmission and distribution systems to function so that retail customers located in the electric utility's services area can receive electric power and energy from suppliers other than the electric utility, and shall include, without limitation, standard metering and billing services.

Delivery Services Tariffs - The tariffs filed with and approved by the ICC that identify the services, terms, conditions, and charges for delivery services under jurisdiction of the ICC.

Direct Access Service Request (DASR) - An electronic request made by a Retail Electric Supplier, Metering Service Provider or a Customer Self-Manager on behalf of a retail customer for delivery services or metering services from the utility. The DASR begins the process of switching the customer from one electric power and energy supplier or metering provider to another.

Distribution System - At its very basic level, the distribution system is the lower voltage, smaller capacity network of wires and equipment that connects the transmission system to the customer.

Electric Utility An entity that has a franchise to sell electricity to retail electric customers in a certain area, as provided in the Public Utilities Act. ComEd is an electric utility.

Electronic Data Interchange (EDI) - The format for the interchange of data electronically, in this case generally pursuant to the American National Standards Institute (ANSI) Utility Industry Group (UIG) standard, with some modifications.

Electronic Funds Transfer (EFT) - EFT is a method of transferring funds electronically between bank accounts to pay invoices.

EDI Transaction - The exchange of data in EDI format, in accordance with one of the approved transaction sets.

EDI Transaction Set - One of the ANSI X 12-defined electronic transactions. A transaction set contains the mandatory, conditional or optional data elements that are used in a particular transaction type.

Energy Imbalance - The difference that occurs between scheduled energy usage and the actual usage of energy during an hour.

Federal Energy Regulatory Commission (FERC) - The federal organization that regulates electric power and energy in inter-state commerce.

General Account Agent - An individual or entity (1) that has been designated by a customer to act on behalf of the customer in arranging and managing tariffed services provided by the Company in regard to one or more designated account(s), and (2) that is designated and acting in accordance with the General Account Agents section of Terms and Conditions.

Host Utility - The electric utility that has the franchise to provide electric power and energy and delivery services in a given territory. ComEd is the host utility in Northern Illinois.

Illinois Commerce Commission (ICC) - The Illinois agency that regulates electric, telephone, and gas utilities, as well as other lines of commerce.

Independent System Operator (ISO) - An organization that is independent of any market participant and that has control of the transmission system, and has continuous, instantaneous information on the state of the transmission system.

kW, kWh - A unit of measurement.

Letter of Authorization (LOA) - An agreement signed by the customer that empowers the Retail Electric Supplier to be the customer's supplier of retail electricity, or that empowers the Metering Service Provider to be the customer's supplier of metering service.

Load or Demand - Usually refers to the amount of electricity used at one time by a customer or group of customers. Load may also refer to the demand placed on the electric system at a given time.

Load Profile - A graph or tabulation that represents the electric load or demand of a customer or group of customers over some period of time.

Load Serving Entity (LSE) - Any entity (or duly designated agent of such an entity), including a load aggregator or power marketer, (i) serving end users within the PJM Control Area, and (ii) that has been granted the authority or has an obligation pursuant to state or local law, regulation or franchise to sell electric energy to end-users located within the PJM Control Area.

Megawatt - A measure of demand that equals 1000 kilowatts. The demand quantities on bills are measured in megawatts or in kilowatts.

Megawatt-hour - A measure of electric energy usage equal to 1,000 kilowatt hours, it represents the delivery of one megawatt of power for a period of one hour. A kilowatt-hour will light a 100-watt bulb for 10 hours or operate a 1,000 watt appliance for one hour. The usage quantities on bills are measured in kilowatt-hours or in megawatt-hours.

Metering Service Provider - A provider of metering service certified by the Illinois Commerce Commission under the provisions of 83 Illinois Administrative Code Part 460.

Metering Service - The group of 16 functions outlined in 83 Illinois Administrative Code Part 460, section 460.15.

Network Integration Transmission Service - Network Integration Transmission Service provides for the use of the transmission system in a manner that allows RESs to efficiently and economically use their network resources as well as other non-designated generation resources to serve their network load located in the Transmission Provider’s control area and any additional load that may be designated by the applicable OATT. The network customer taking Network Integration Transmission Service must obtain or provide ancillary services as required by the OATT.

Network Resource - A Network Resource is any designated generating resource owned, purchased, or leased by a network customer under the Network Integration Transmission Service provisions of the applicable OATT. Network resources do not include any resource, or any portion thereof, that is committed for sale to third parties or otherwise cannot be called upon to meet the network customer’s network load on a non-interruptible basis.

Network Service Peak Load (NSPL) NSPL is used to determine a network transmission charge and/or allocate network service Financial Transmission Rights (FTR’s) or Auction Revenue Rights (ARR’s).

Non-firm Point-to-Point Transmission Service - Non-firm Point-to-Point Transmission Service provides for the use of the transmission system in a manner that is reserved and/or scheduled between specified points of receipt and delivery on the transmission system, and that is reserved and scheduled on an as-available basis and is subject to curtailment or interruption, in accordance with the terms of the applicable OATT. This transmission service may be available on a stand-alone basis for periods ranging from one hour to one month and is provided under the applicable OATT.

Open Access - A key component of the restructuring process that allows customers to obtain access to a utility’s delivery services, separate from the purchase of electric power and energy and to purchase their power and energy from qualified suppliers.

Open Access Same-Time Information System (OASIS) - The information system and standards of conduct contained in Part 37 of the Federal Energy Regulatory Commission's regulations and all additional requirements implemented by subsequent Commission orders dealing with OASIS. The OASIS will provide information by electronic means about available transmission capability for point-to-point service and will provide a process for requesting transmission service. OASIS will enable Transmission Providers and Transmission Customers to promptly communicate requests and responses to buy and sell available transmission capacity offered under the Transmission Provider's tariff.

Open Access Transmission Tariff (OATT) - Filed with the FERC, this tariff sets the rates, terms and conditions under which transmission and ancillary transmission services are provided. It contains sections pertaining to both Point-To-Point Transmission Service and Network Integration Transmission Service in conjunction with applicable Common Service Provisions and appropriate Schedules and Attachments.

Peak Load Contribution (PLC) - A customers contribution to a zone’s normalized summer peak load, as estimated by the zone’s Electrical Distribution Company (EDC). PLC is used to determine a Load Serving Entity’s (LSE’s) Obligation peak load.

PJM Interconnection, LLC (PJM) - An RTO that operates the world’s largest competitive wholesale electricity market and North America’s largest central dispatch control area.

Power Purchase Option (PPO) - A service governed by tariff, which allows retail electric customers to buy electric power and energy from ComEd at a market value of power and energy.

Rate MSPS Metering Service Provider Service - The tariff filed with and approved by the Illinois Commerce Commission (ICC) that identifies the services, terms, conditions and charges for metering service under jurisdiction of the ICC.

Reliability - The ability of an electric system to deliver electric power and energy to customers continuously under different conditions.

Residual Meter Usage Data - Residual usage occurs when a delivery services customer switches its provider of metering service; and refers to usage that is registered on a meter from the time it is last read to the time when the meter is exchanged.

Retail Electric Supplier (RES) - The term that includes both an ARES (see above) and an Illinois jurisdictional utility other than the host utility that sells electricity to retail electric customers in the host utility’s service area.

Retail Load Responsibility (RLR) Schedule - A schedule that a RES submits to PJM daily that shows the aggregate electric power and energy (including losses on the transmission and distribution systems) that a RES expects to provide in ComEd’s service area for each hour of the calendar day.

Single Bill Option - The option in which a Retail Electric Supplier submits a single bill to the customer that includes electricity supply and the delivery services charges of the host utility. The use of the single bill option is submitted as part of the enrollment DASR.

"Slamming" - Slamming refers to the unlawful switching of providers without the consent or knowledge of the customer.

Tariff - A document, approved by the ICC, that contains the terms, conditions, and prices for electric services. There may be separate tariffs for different services and products.

Trading Partner - One of the parties participating in an electronic data exchange. Using the term trading partner does not imply that ComEd has a partnership or joint venture relationship with the RES, MSP, Customer Self-Manager or any other party.

Transmission Customer - A Transmission Customer is any eligible customer (or its designated agent) that either executes a service agreement with the Transmission Provider or requests in writing that the Transmission Provider file a proposed, unexecuted service agreement with the FERC to receive transmission service under Part II of the OATT. This term is used in the OATT Part I Common Service Provisions to include customers receiving transmission service under Part II and Part III of the OATT.

Transmission Provider - The Transmission Provider is the entity that provides service on the transmission system located in ComEd’s service territory. PJM fulfills the roles of Control Area Operator and Transmission Provider within the ComEd service territory.

Transmission System - The high voltage system used to transport power across the central area to points of delivery on the distribution system.