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C. – Case: When placed before the PUC assigned proceeding number, such as C.01-02-003.

CAA – Clean Air Act:  Legislation passed in 1988 and amended in 1992 and 1996 that mandates a planning process to attain state environmental air quality standards.

Cable Modem: A device enabling a user to connect a personal computer to a local cable television line.

CAC – Carrier Access Code:  The number sequence a caller dials to obtain access to the services of a carrier.

CADER – California Alliance for Distributed Energy Resources:  A nonprofit organization committed to advancing the successful use of highly efficient and environmentally responsible distributed energy resources into competitive energy markets.

CADMAC – California Demand-Side Management Measurement Advisory Committee:  An organization that provides a forum for regional and state energy efficiency programs using Public Goods Charge funds.  Members include the PUC, the Office for Ratepayer Advocates, the California Energy Commission, Pacific Gas and Electric, Sempra, Southern California Edison and the National Resources Defense Council.

CAIDI – Customer Average Interruption Duration Index:  The average length of an interruption, weighted by the number of customers affected, for customers affected during a specific time period.  It is calculated by adding the customer-minutes off during each interruption and dividing the sum by the number of customers experiencing one or more sustained interruptions (greater than one minute) during the time period.  The resulting unit is minutes.

CalAm – California -American Water Company:  On the Internet at

CALC – Customer Access Line Charge:  The Federal Communications Commission (FCC) imposed a monthly surcharge added to all local bills to recover a portion of the cost of telephone poles, wires, etc. from consumers. Before deregulation, a large part of these costs were financed by long distance users in the form of higher charges.

CALEP – California Association of Lighting Efficiency Professionals:  An association of companies specializing in energy-efficient lighting that works with the California Board for Energy Efficiency to turn the energy-efficiency marketplace into a market-driven industry.

CALFED - California/Federal: A joint federal and state entity working to find long-term solutions for California waterways.

CAL-OSHA – California Office of Occupational Safety and Health Administration: The Cal/OSHA Program is responsible for enforcing California laws and regulations pertaining to workplace safety and health and for providing assistance to employers and workers about workplace safety and health issues.  On the Internet at

CalPERs – California Public Employees' Retirement System: manages retirement and health plans for the state of California and local government agencies.  On the Internet at

CAO – Control Area Operator:  The operator of an electric power system bound by interconnection (tie-line) metering and telemetry.  It controls generation to maintain its interchange schedule with other control areas, to maintain instantaneous load/resource balance within its system, and contributes to frequency regulation of the interconnection.

Capability: The amount of electric power delivered or required for which a generator, turbine, transformer, transmission circuit, station, or system is rated by the manufacturer.

Capacity: The amount of electric power delivered or required for which a generator, turbine, transformer, transmission circuit, station, or system is rated by the manufacturer.

Capacity Charge: An element in a two-part pricing method used in capacity transactions (energy charge is the other element). The capacity charge, sometimes called Demand Charge, is assessed on the amount of capacity being purchased.

CAPs – Competitive Access Providers:  Common carriers who provide local service and compete against local telephone companies' services.

CARE – California Alternatives Rates for Energy:  A PUC program for eligible low-income customers in which those enrolled can receive a 20 percent discount on their monthly electric and gas bills and are exempt from the rate increases approved in 2001 for Southern California Edison (Edison), Pacific Gas and Electric (PG&E), and San Diego Gas and Electric (SDG&E).  CARE is funded through a rate surcharge paid by all other utility customers.

Carrier: A long distance company that uses its own transmission facilities.

CBOs – Community-Based Organizations: Organizations dedicated to bettering the community through job training, public program information and assistance, and other help.

CC – Common Carrier:  A government-regulated private company that provides the public with telecommunications services and facilities.

CC – Cost Component:  The price of each type of long distance service and/or equipment that makes up a communications system.

CCA – Community Choice Aggregators: A community organization of electricity customers who group together to solicit bids, broker, and contract for electricity and energy services to facilitate the sale and purchase of electricity and other related services on behalf of local citizens, businesses, and itself.

Ccf: One hundred cubic feet.  A unit of water; one cf equals 748 gallons.

CCLC – Carrier Common Line Charge:  A per-minute charge paid by long distance companies to local phone companies or the use of local public switched networks at either or both ends of a long distance call. This charge goes to pay part of the cost of telephone poles, wires, etc.

CCSA – Common Control Switching Arrangement:  The use of carrier switches under a carrier's control as part of a customer's private network.

CE - Conditioning Equipment:  Equipment modifications or adjustments necessary to match transmission levels and impedances and which equalize transmission and delay to bring circuit losses, levels, and distortion within established standards.

CEC – California Energy Commission:  A state agency responsible for, among other things, forecasting future energy needs and keeping historical energy data, licensing thermal power plants 50 megawatts or larger, promoting energy efficiency through appliance and building standards, and developing energy technologies and supporting renewable energy.  It is overseen by a Governor-appointed five-person board.

CEERT – Center for Energy Efficiency and Renewable Technologies: Nonprofit organization of concerned scientists, environmentalists, public interest advocates and innovative technology companies involved in developing innovative energy technologies that share a vision to benefit the environment with sustainable solutions to California's growing appetite for energy. On the Internet at

Cellular: A mobile communications system using combination of radio and telephone switching to allow telephone communication to and from mobile users.

CEMA – Catastrophic Event Memorandum Account: The PUC allows utilities to open Catastrophic Event Memorandum Accounts by filing an Advice Letter after a catastrophic event occurs. By timely filing this Advice Letter, utilities are permitted to track all catastrophic event costs for subsequent recovery, after a review of their reasonableness.

Centralized Credit Check System: A program that California 's seven largest telephone companies participate in to detect and prevent cheating by customers who deliberately avoid paying their telephone bills.

¢/kWh: Cents per kilowatt-hour.

CEO: Chief Executive Officer.

CalEPA – California Environmental Protection Agency:  Created in 1991 by Governor's Executive Order. The six Boards, Departments and Office were placed within the Cal/EPA "umbrella" to create a cabinet level voice for the protection of human health and the environment and to assure the coordinated deployment of State resources. Our mission is to restore, protect and enhance the environment, to ensure public health, environmental quality and economic vitality.

CEQA – California Environmental Quality Act: The principal statute mandating environmental assessment of projects in California . The purpose of CEQA is to evaluate whether a proposed project may have an adverse effect on the environment and, if so, if that effect can be reduced or eliminated by pursuing an alternative course of action or through mitigation.

CFCA – Core Fixed Cost Account:  A balancing account that matches the authorized base revenue requirement and certain other costs for core customers with recorded revenues intended to recover that revenue requirement and the other specified costs.  Like balancing accounts, the CFCA provides for any overcollection or undercollection of revenues, plus interested to be refunded to or recovered from ratepayers.

CFEE – California Foundation on the Environment and the Economy: The California Foundation on the Environment and the Economy brings together business, labor, community, and environmental leadership with legislative and regulatory officials and expert academicians, in forums designed to address complex economic and social issues.  On the Internet at

CFO: Chief Financial Officer.

CFS: Cubic feet per second. One cubic foot is about 7.5 gallons.

Channel: A communications path via a carrier or microwave radio.

CIAC – Contributions in Aid of Construction: Non-refundable contributions in cash or properties from individuals, governmental agencies, or others for construction or property additions.  The utility may not earn a return on such contributions.

CIC – Carrier Identification Code:  The three-digit number that uniquely identifies a carrier. The Carrier Identification Code is indicated by XXX in the Carrier Access Code: The same code applies to an individual carrier throughout the area served by the North American Numbering Plan.

Circuit: A conductor or a system of conductors through which electric current flows.  Or, a two-way communications path for the transmission of electromagnetic signals.

Circuit Switching: A switching system that completes a dedicated transmission path from sender to receiver.

CIS – Case Information System: An electronic system of document management.

CLCs – Competitive Local Carriers: Telecommunications companies that compete with local telephone companies in providing local exchange service.

CLEC – Competitive Local Exchange Carrier:  A telecommunications provider that competes with other carriers.

CLMA – Conservation Load Management Adjustment: Tracks an electricity utility's actual expenditures and compares them with the amount allowed for conservation and load management programs authorized in a general rate case.

CMR – Cellular Mobile Radio:  A high-capacity land mobile radio system in which an assigned frequency spectrum is divided into discrete channels that are assigned to a cellular geographic serving area.

CO – Central Office:  With local telephone companies, the nearby building containing the local telecommunication switch that provides local telephone service.

COAM – Customer-Owned and Maintained:  Customer-provided communications equipment and associated wiring.

COAX – Coaxial Cable: A type of cable that can carry large amounts of bandwidth over long distances.

COC – Cost of Capital: The cost to a company of acquiring funds to finance its operations, including borrowed money, preferred stock dividends, etc.

CODEC – Coder-Decoder:  Used to convert analog signals to digital form for transmission over a digital median and back again to the original analog form.

Co-generation: The sequential production from the same fuel source of thermal energy and electrical mechanical power, such as the generation of electricity using waste heat from an industrial process.

Co-generator: A generating facility that produces electricity and another form of useful thermal energy (such as heat or steam), used for industrial, commercial, heating, or cooling purposes. To receive status as a qualifying facility (QF) under the Public Utility Regulatory Policies Act (PURPA), the facility must produce electric energy and "another form of useful thermal energy through the sequential use of energy," and meet certain ownership, operating, and efficiency criteria established by the Federal Energy Regulatory Commission (FERC).

Cold Water Pool: The colder water at the deepest part of a reservoir.

Coli Form Bacteria: Bacteria found in soil and water.

Combined Cycle: An electric generating technology in which electricity is produced from otherwise lost waste heat exiting from one or more gas (combustion) turbines. The exiting heat is routed to a conventional boiler or to a heat recovery steam generator for utilization by a steam turbine in the production of electricity. This process increases the efficiency of the electric generating unit.

Combined Cycle Unit: An electric generating unit that consists of one or more combustion turbines and one or more boilers with a portion of the required energy input to the boiler(s) provided by the exhaust gas of the combustion turbine(s).

Combined Pumped-Storage Plant: A pumped-storage hydroelectric power plant that uses both pumped water and natural stream flow to produce electricity.

Commercial: A utility's consumers that are non-manufacturing business establishments, including hotels, motels, restaurants, wholesale businesses, retail stores, and health, social, and educational institutions. The utility may classify commercial service as all consumers whose demand or annual use exceeds some specified limit. The limit may be set by the utility based on the rate schedule of the utility.

Commission Meetings: Official sessions of the PUC, held about every two weeks to which the public is invited to observe.  Proposed Decisions, Orders, and Resolutions may be discussed and voted upon.

Common Carrier: Any person or facilities for the transportation of property or passengers.  Common carriers must accept all business offered to them at posted rates.  For interstate commence, they are regulated by the Interstate Commerce Commission (ICC); for intrastate, by the Commission.  In the telecommunications industry, the term refers to any person engaged as a carrier for hire in interstate or foreign communications by wire or radio.

Competitive Bidding Rule: A PUC requirement that a utility seeking to issue securities publicly invite competitive bids from financial institutions wishing to buy or resell the issue.

Complaint: A charge by any person or group that a utility or transportation company under PUC jurisdiction has violated a law, order, tariff, or rule of the PUC.

Complainant: A person or group that files a complaint charging a utility with a violation of a law, order, tariff, or rule of the PUC.

Cone of Depression: A drop in the water table.

Configuration: The combination of long-distance services and/or equipment that make up a communications system.

Congestion: A condition that occurs when insufficient transfer capacity is available to implement all of the preferred schedules for electricity transmission simultaneously.

Conjunctive Use: The planned joint use of surface and groundwater to improve overall water supply reliability.

Conservation Pricing: Pricing that provides an incentive to reduce average or peak use, or both.

Consumptive Use: A use that makes water unavailable for other uses.

Contract Price: Price of fuels marketed on a contract basis covering a period of one or more years. Contract prices reflect market conditions at the time the contract was negotiated and therefore remain constant throughout the life of the contract or are adjusted through escalation clauses. Generally, contract prices do not fluctuate widely.

Convergence: Providers that can deliver products that compete with those now delivered by other networks.

COPTS – Customer-Owned Pay Telephone Service: Private firms and individuals can own the pay telephones in their establishments or on other private premises.  The COPTS owner sets the amount charged for calls, subject to a PUC maximum rate.

Core/Noncore: Two basic customer classes. Core includes residential and small business users.  Noncore includes large industrial users who generally also have the ability to switch to other fuels.  Some large companies prefer to be treated like core customers, have the utility purchase and deliver gas or electricity for them, but pay a handling fee to the utility for special treatment.

Corrosively: A measure of the ability of water to corrode pipes.

COS – Class of Service/Class Mark:  A sub-grouping of telephone customers for the sake of rate distinction or limitation of service.

COS – Cost of Service: A method of using utility costs in rate design; a cost of service study measures a utility's costs incurred in serving each customer class, including a reasonable return on investment.

Cost-Based Pricing: A method of setting rates so that a utility can recover the costs of providing that particular service.

COU – Consumer-owned Utility:  Independent, usually electric, utility established to provide at-cost electricity to its members.  Also known as a "cooperative."  The utility will generate, transmit, and/or distribute supplies of electric energy to a specified area not being serviced by another utility. Such ventures are generally exempt from Federal income tax laws. Most electric cooperatives have been initially financed by the Rural Electrification Administration, U.S. Department of Agriculture.

CPCN – Certificate of Public Convenience and Necessity: Prior to beginning operations or making significant additions to its plants, a public utility must apply to the Commission for permission.  This procedure helps ensure that no plant facilities are built, or transportation services begun, that the public does not need.  The meaning of this term is not spelled out by statute, however, and the Commission has broad discretion in granting or denying these applications.

CPE – Customer Premise Equipment: Telephone equipment located on the customer's premises including telephone receivers, dialers, key systems, recorders, private branch exchanges, and call-directors.  All new CPC purchased since January 1, 1984 , has been deregulated.

CPI – Customer Price Index:  An index measuring the change in the cost of typical wage earner purchases of goods and services in some base period; also, cost-of-living index

CPP – Critical Peak Pricing: A time-of-use pricing that effectively reduces a customer's electricity consumption.

CPSD – Consumer Protection and Safety Division: A Division of the PUC that administers safety oversight of railroads; light rail transit systems and highway/rail crossings; licensing, consumer protection, and safety oversight of motor carriers of passengers, household goods and water vessels; and regulatory oversight of hot air balloons and some air carriers.

CPU – Central Processing Unit: The main part of a computer that contains the arithmetic and logic unit and the memory and control unit and carries out instructions, controls the functioning of all peripheral units, and coordinates operations.

Cramming: Refers to the placement of charges on a consumer's bill that the consumer has not authorized.

CRS - California Relay Service: Provides specially-trained operators to relay telephone conversations back and forth between people who are deaf, hard of hearing, or speech-disabled and all those they wish to communicate with by telephone. On the Internet at

CRS – Cost Responsibility Surcharge: The mechanism by which the PUC has allocated costs associated with past utility and Department of Water Resources commitments to Direct Access customers.

CRSAC – California Relay Service Advisory Committee: Advises the Telecommunications Access for the Deaf and Disabled Administrative Committee (TADDAC) in regard to the California Relay Service, including matters of policy, procedure, finance and public awareness. This committee operates under the direction of the PUC.

CRT – Cathode-ray Tube: An electronic tube, like a television tube, that is used to display images from a computer (both words and graphics) on a video screen.  Also called a monitor.

CS – Carrier System:  A system for providing several communication channels over a single path.

CS&I - Customer Service and Information: A Division of the PUC that focuses on providing information and assistance to the general public, including bilingual communication and outreach to better serve California 's diverse population.  The Division includes the Public Advisor's Office, Consumer Affairs Branch (CAB), and Utility Supplier Diversity program.

CT – Combustion Turbine:  Essentially a permanently mounted jet engine (that works by continuously burning a mixture of fuel and compressed air in a combustion chamber to produce a jet of hot exhaust gas that spins the turbine blades) used to turn a generator. CTs are usually used to meet load during peak demand times; also called gas combustion turbines, or GTs.

CT – Cross Talk:  The unwanted energy (speech or tone) transferred from one circuit to another circuit.

CTAP – California Telephone Access Program: Distributes telecommunications equipment and services to individuals certified as having difficulty using the telephone. CTAP is a California State mandated program, under governance of the PUC. On the Internet at

CTCs - Competition Transition Charges: A nonpassable charge on the bills of each customer of the distribution utility, including those who are served under contracts with non-utility suppliers, for recovery of the utility's transition costs arising from deregulation.

CTT – Cable Television Transmission:  The transmission, usually for a fee, of television signals.

CU – Control Unit:  The central processor of a telephone switching device.

Current (Electric): A flow of electrons in an electrical conductor. The strength or rate of movement of the electricity is measured in amperes.

Customer Choice: Allowing all customers to purchase kilowatt-hours of electricity from any of a number of companies that compete with each other.

Cut: To transfer a service from one facility to another.

Cut Through: The establishment of a complete path for signaling and/or California 's federally-owned and operated water project, consisting of 20 dams and reservoirs and 500 miles of canals that deliver 8 millionaire-feet of water each year, primarily to Central Valley farmers.

CVPIA – Central Valley Project Improvement Act:  This Act amends the CVP reauthorization act of 1937 and reauthorized the CVP to add mitigation, protection, and restoration of fish and wildlife as project purposes equal to agricultural and domestic uses, and to make fish and wildlife enhancement a project purpose equal to power.

CWA – Clean Water Act:  The law governing health of the nation's rivers, lakes, estuaries and coastal waters.  It was originally enacted in 1948 as the Federal Water Pollution Control Act. In 1972 it was revised and renamed the Clean Water Act.

CWIP – Construction Work in Progress: A bookkeeping account that accumulates all costs in building new plant facilities until they begin to serve the public, at which time they are transferred to the appropriate plant accounts and included in rate base.

Cyberspace: Where human interaction occurs over computer networks, through email or games.

Cycle Billing: The process of reading only part of a system's meters each day and then billing that portion of its customers.  By the end of the cycle, usually a month, the complete system is read and billed, and a new cycle begins.


Last Modified: 1/28/2008

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