(A - E) (F - J) (K - O) (P - T) (U - Z)

  • Parallel Path Flow : This refers to the flow of electric power on an electric system's transmission facilities resulting from scheduled electric power transfers between two other electric systems. (Electric power flows on all interconnected parallel paths in amounts inversely proportional to each path's resistance.)
  • Partial Load : An electrical demand that uses only part of the electrical power available.
  • Payback : The length of time it takes for the savings received to cover the cost of implementing the technology.
  • Peak : Periods of relatively high system demands.
  • Peak Clipping : Peak clipping reduces a utility's system peak, reducing the need to operate peaking units with relatively high fuel costs. Peak clipping is typically pursued only for the days the system peak is likely to occur, and the resources are not expected to meet the impending load requirements.
  • Peak Demand : Maximum power used in a given period of time.
  • Peak Load Power plant : A power generating station that is normally used to produce extra electricity during peak load times.
  • Peaking Capacity : Generating equipment normally operated only during the hours of highest daily, weekly, or seasonal loads; this equipment is usually designed to meet the portion of load that is above base load.
  • Peaking Unit : A power generator used by a utility to produce extra electricity during peak load times.
  • Performance Attributes : Performance attributes measure the quality of service and operating efficiency. Loss of load probability, expected energy curtailment, and reserve margin are all performance attributes.
  • Period of Analysis : The number of years considered in the study.
  • Phase : One of the characteristics of the electric service supplied or the equipment used. Practically all residential customers have single-phase service. Large commercial and industrial customers have either two-phase or three-phase service.
  • Photovoltaics : A technology that directly converts light into electricity. The process uses modules, which are usually made up of many cells (thin layers of semiconductors).
  • Pilot : A utility program offering a limited group of customers their choice of certified or licensed energy suppliers on a one year minimum trial basis.
  • Planned Generator : Proposal to install generating equipment at an existing or planned facility or site.
  • Plant : A facility containing prime movers, electric generators, and other equipment for producing electric energy.
  • Point(s) of Delivery : Point(s) for interconnection on the Transmission Provider's System where capacity and/or energy are made available to the end user.
  • Point(s) of Receipt : Point(s) of connection to the transmission system where capacity and/or energy will be made available to the transmission providers.
  • Point-to-Point Transmission Service : Reservation and/or transmission of energy from point(s) of receipt to point(s) of delivery.
  • PoolCo : This will serve as a model for the restructured electric industry that combines the functions of an ISO and a Power Exchange. In its least flexible form, a PoolCo also prohibits direct transactions between buyers and sellers (I.e. all producers selling to the Pool and all consumers buy from the Pool.)
  • Power : The rate at which energy is transferred.
  • Power Exchange : This is a commercial entity responsible for facilitating the development of transparent spot prices for energy capacity, and/or ancillary services.
  • Power Grid : A network of power lines and associated equipment used to transmit and distribute electricity over a geographic area.
  • Power Marketers : Entities engaged in buying and selling electricity.
  • Power Plant : A generating station where electricity is produced.
  • Power Pool : Two or more interconnected electric systems that agree to coordinate operations.
  • Power Purchase Agreement : This refers to a contract entered into by an independent power producer and an electric utility. The power purchase agreement specifies the terms and conditions under which electric power will be generated and purchased. Power purchase agreements require the independent power producer to supply power at a specified price for the life of the agreement. While power purchase agreements vary, their common elements include: specification of the size and operating parameters of the generation facility; milestones in-service dates, and contract terms; price mechanisms; service and performance obligations; dispatchability options; and conditions of termination or default.
  • Present Value : The amount of money required to secure a specified cash flow on a future date at a given rate of return.
  • Present Worth Factor : The adjustment factor that discounts a sum of future dollars back to the current year.
  • Price Cap : Situation where a price has been determined and fixed.
  • Primary Circuit : This is the distribution circuit (less than 69,000 volts) on the high voltage side of the transformer.
  • Prime Mover : A device such as an engine or water wheel that drives an electric generator.
  • Production : The act or process of generating electric energy.
  • Production Costing : A method used to determine the most economical way to operate a given system of power resources under given load conditions.
  • Program Life : The length of time that the utility will be actively involved in promoting a demand-side management program (I.e. financing the marketing activities and the incentives of the program.)
  • Program Maturity : The time it takes for the full benefits of a demand-side management measure or program to be realized.
  • Project Financing : This is the most commonly used method to finance the construction of independent power facilities. Typically, the developer pledges the value of the plant and part or all of its expected revenues as collateral to secure financing from private lenders.
  • Prorated Bills : The computation of a bill based upon proportionate distribution of the applicable billing schedule. A prorated bill is less than 25 days ore more than 38 days.
  • Provider of Last Resort : A legal obligation (traditionally given to utilities) to provide service to a customer where competitors have decided they do not want that customer's business.
  • Public Authority Service to Public Authorities : Electric services supplied to public entities such as municipalities or divisions of state or federal governments.
  • Public Utility : A utility operated by a non-profit governmental or quasi-governmental entity. Public utilities include municipal utilities, cooperatives, and power marketing authorities.
  • Public Utility Commissions : State regulatory agencies that provide oversight, policy guidelines and direction to electric public utilities.
  • Public Utility Holding Company Act of 1935 (PUHCA) : PUHCA was enacted by the U.S. Congress to regulate the large interstate holding companies that monopolized the electric utility industry during the early 20th century.
  • Public Utility Regulatory Policies Act of 1978 (PU : PURPA promotes energy efficiency and increased use of alternative energy sources by encouraging companies to build cogeneration facilities and renewable energy projects using wind power, solar energy, geothermal energy, hydropower, biomass, and waste fuels.
  • Publicly Owned Utilities : Municipal utilities (utilities owned by branches of local government) and/or co-ops (utilities owned cooperatively by customers).
  • Pumped Storage : A facility designed to generate electric power during peak load periods with a hydroelectric plant using water pumped into a storage reservoir during off-peak periods.
  • Purchased Power Adjustment : A clause in a rate schedule that provides for adjustments to a bill when energy from another system is acquired.
  • Qualifying Facility : A cogeneration of small production facility that meets criteria established by the Federal Energy Regulatory Commission.
  • Ramp Rate : The rate at which you can increase load on a power plant. The ramp rate for a hydroelectric facility may be dependent on how rapidly water surface elevation on the river changes.
  • Ramp Up (Supply Side) : Increasing load on a generating unit at a rate called the ramp rate.
  • Ramp-Up (Demand-Side) : Implementing a demand-side management program over time until the program is considered fully installed.
  • Rate Base : Value of property upon which a utility is permitted to earn a specific rate of return.
  • Rate Class : A group of customers identified as a class and subject to a rate different from the rates of other groups.
  • Rate Structure : The design and organization of billing charges by customer class to distribute the revenue requirement among customer classes and rating period.
  • Rate-Basing : The practice by utilities of allotting funds invested in utility Research Development Demonstration and Commercialization and other programs from ratepayers, as opposed to allocating these costs to shareholders.
  • Rate-of-Return Rates : Rates set to the average cost of electricity as an incentive for regulated utilities to operate more efficiently at lower rates where costs are minimized.
  • Ratemaking Authority : The utility commission's authority as designated by a State or Federal legislature to fix, modify, and/or approve rates.
  • Ratepayer : This is a retail consumer of the electricity distributed by an electric utility. This includes residential, commercial and industrial users of electricity.
  • Real-time Pricing : The instantaneous pricing of electricity based on the cost of the electricity available for use at the time the electricity is demanded by the customer.
  • Receiving Party : Entity receiving the capacity and/or energy transmitted by the transmission provider to the point(s) of delivery.
  • Recovered Energy : Reused heat or energy that otherwise would be lost. For example, a combined cycle power plant recaptures some of its own waste heat and reuses it to make extra electric power.
  • Regional Power Exchange : An entity established to coordinate short-term operations to maintain system stability and achieve least-cost dispatch. The dispatch provides back-up supplies, short-term excess sales, reactive power support, and spinning reserve. The pool may own, manager and/or operate the transmission lines or be an independent entity that manages the transactions between entities.
  • Regional Reliability Councils : Regional organizations charged with maintaining system reliability even during abnormal bulk power conditions such as outages and unexpectedly high loads.
  • Regional Transmission Group : An organization approved by a Commission to coordinate transmission planning (and expansion), operation, and use on a regional basis.
  • Regulation : An activity of government to control or direct economic entities by rulemaking and adjudication.
  • Regulatory Compact : Under this compact, utilities are granted service territories in which they have the exclusive right to serve retail customers. In exchange for this right, utilities have an obligation to serve all consumers in that territory on demand.
  • Reliability : Electric system reliability has two components - adequacy and security. Adequacy is the ability of the electric system to supply the aggregate electric demand and energy requirements of the customers at all times, taking into account scheduled and unscheduled outages of system facilities. Security is the ability of the electric system to withstand sudden disturbances such as electric short circuits or unanticipated loss of system facilities.
  • Reliability Councils : Regional reliability councils were organized after the 1965 northeast blackout to coordinate reliability practices and avoid or minimize future outages. They are voluntary organizations of transmission-owning utilities and in some cases power cooperatives, power marketers, and non-utility generators. Membership rules vary from region to region. They are coordinated through the North American Electric Reliability Council.
  • Renewable Energy : Energy that is capable of being renewed by the natural ecological cycle.
  • Replacements : The substitution of a unit for another unit generally of a like or improved character.
  • Repowered Plant : This is an existing power facility that has been substantially rebuilt to extend its useful life.
  • Reregulation : The design and implementation of regulatory practices to be applied to the remaining regulated entities after restructuring of the vertically-integrated electric utility. The remaining Regulated entities would be those that continue to exhibit characteristics of a natural monopoly, where imperfections in the market prevent the realization of more competitive results, and where, in light of other policy considerations, competitive results are unsatisfactory in one or more respects. Reregulation could employ the same or different regulatory practices as those used before restructuring.
  • Resellers : Companies that purchase utility service from a wholesaler and resell it to consumers.
  • Reserve Capacity : Capacity in excess of that required to carry peak load.
  • Reserve Generating Capacity : The amount of power that can be produced at a given point in time by generating units that are kept available in case of special need. This capacity may e used when unusually high power demand occurs, or when other generating units are off-line for maintenance, repair or refueling.
  • Reserve Margin : The percentage of installed capacity exceeding the expected peak demand during a specified period.
  • Restructuring : The reconfiguration of the vertically-integrated electric utility. Restructuring usually refers to separation of the various utility functions into individually-operated and-owned entities.
  • Retail : Sales of electric energy to the ultimate customer.
  • Retail Company : A company that is authorized to sell electricity directly to industrial, commercial and residential end-users.
  • Retail Competition : A system under which more than one electric provider can offer to sell to retail customers, and retail customers are allowed to choose more than one provider from whom to purchase their electricity.
  • Retail Transaction : The sale of electric power from a generating company or wholesale entity to the customer.
  • Retail Wheeling : This refers to the ability of end-use customers of any size to purchase electric capacity, energy or both from anyone other than the local electric utility by moving or wheeling such power over the local utility's transmission and/or distribution lines.
  • Rolling Blackouts : A controlled and temporary interruption of electrical service. These are necessary when a utility is unable to meet heavy peak demands because of an extreme deficiency in power supply.
  • Running and Quick-Start Capability : Generally refers to generating units that can be available for load within a 30-minute period.
  • Rural Electric Cooperative : A nonprofit, customer-owned electric utility that distributes power in a rural area.
  • Sales for Resale : Energy supplied to other utilities and agencies for resale.
  • Savings Fraction : The percentage of consumption from using the old technology that can be saved by replacing it with the new, more efficient demand-side management technology. For example, if a 60-watt incandescent lamp were replaced with a 15-watt compact fluorescent lamp, the savings fraction would be 75 percent because the compact fluorescent lamp uses only 25 percent of the energy used by the incandescent lamp.
  • Scheduled Outage : An outage that results when a component is deliberately taken out of service at a selected time, usually for the purposes of construction, maintenance, or testing.
  • Securitization : The act of pledging assets to a creditor through a note, lien or bond. This is a mechanism to allow a utility to recover stranded costs up front in a single lump sum payment. Under a securitization scheme, the legislature or utility commission orders customers to pay a surcharge as part of their electric bill. That surcharge must be paid within the utility's original service territory, regardless of who supplies the electricity to customers.
  • Self-Generation : A generation facility dedicated to serving a particular retail customer, usually located on the customer's premises. The facility may either be owned directly by the retail customer or owned by a third party with a contractual arrangement to provide electricity to meet some or all of the customer's load.
  • Service Agreement : an agreement entered into by the transmission customer and transmission provider.
  • Service Area : The territory a utility system is required or has the right to supply electric service to ultimate customers.
  • Service Drop : The lines running to a customer's house. Usually a service drop is made up of two 120 volt lines and a neutral line, from which the customer can obtain either 120 or 240 volts of power. When these lines are insulated and twisted together, the installation is called triplex cable.
  • Service Life : The length of time a piece of equipment can be expected to perform at its full capacity.
  • Service Territory : This is the state, area or region served exclusively by a single electric utility.
  • Single Phase Line : This carriers electrical loads capable of serving the needs of residential customers, small commercial customers, and streetlights. It carrier a relatively light load as compared to heavy duty three phrase constructs.
  • Small Power Producer : Refers to a producer that generates at least 75% of its energy from renewable sources.
  • Solar Thermal Electric : A process that generates electricity by converting incoming solar radiation to thermal energy.
  • Source Energy : All the energy used in delivering energy to a site, including power generation and transmission and distribution losses, to perform a specific function, such as space conditioning, lighting, or water heating. Approximately three watts (or 10.239 Btus) of energy is consumed to deliver one watt of usable electricity.
  • Southeastern Electric Reliability Council (SERC : One of the ten regional reliability councils that make up the North American Electric Reliability Council (NERC).
  • Southwest Power Pool (SPP) : One of the ten regional reliability councils that make up the North American Electric Reliability Council (NERC).
  • Spinning Reserve : Reserve generating capacity running at zero load.
  • Split-the-savings : The basis for settling economy-energy transactions between utilities. The added cost of the supplier are subtracted from the avoided costs of the buyer, and the difference is evenly divided.
  • Spot Purchases : Single shipment of fuel purchased for delivery within 1 year.
  • Stable Prices : Prices that do not vary greatly over short time periods.
  • Standard Rate : The basic rate customers would take service under if they were not on real-time pricing.
  • Standby Facility : A facility that supports a system and generally running under no load.
  • Stocks : A supply of fuel accumulated for future use.
  • Stranded Benefits : Special collection programs, renewable energy and demand side management programs, lifeline rates and other utility resources funded by a monopoly utility that may not be funded if the utility's competition does not have smaller costs.
  • Stranded Commitment : Assets and contracts associated with shifting to competition which are above market prices and result in non-competitive conditions for the utility.
  • Stranded Investments/Costs : Utility investments in facilities built to serve customers under traditional regulation may become unrecoverable or "stranded" if those assets are deregulated and their cost of generation exceeds the actual price of power in a competitive market. These include prior investments allowed by regulators that are currently being recovered through regulated rates.
  • Stranded/Strandable Costs : These are costs inherent in the existing electric utility industry rendered potentially unrecoverable in a competitive market.
  • Strategic Conservation : Strategic conservation results from load reductions occurring in all or nearly all time periods. This strategy can be induced by price of electricity, energy-efficient equipment, or decreasing usage of equipment.
  • Strategic Load Growth : A form of load building designed to increase efficiency in a power system. This load shape objective can be induced by the price of electricity and by the switching of fuel technologies (from gas to electric).
  • Substation : A facility used for switching and/or changing or regulating the voltage of electricity. Service equipment, line transformer installations, or minor distribution or transmission equipment are not classified as substations.
  • Summer Peak : The greatest load on an electric system during any prescribed demand interval in the summer.
  • Supplier : A person or corporation, generator, broker, marketer, aggregator or any other entity, that sells electricity to customers, using the transmission or distribution facilities of an electric distribution company.
  • Supply-Side : Technologies that pertain to the generation of electricity.
  • Surplus : Excess firm energy available from a utility or region for which there is no market at the established rates.
  • Switching Station : Facility used to connect two or more electric circuits through switches.
  • System (Electric) : Physically connected generation, transmission, and distribution facilities operating as a single unit.
  • System Peak Demand : The highest demand value that has occurred during a specified period for the utility system.
  • Systems Benefits Charge : This is a per-customer charge intended to recover the costs of utility demand-side management reach and development, renewable resources or low-income programs.
  • Target Market : A specific group of people or geographical area that has been identified as the primary buyers of a product or service.
  • Tariff : A document, approved by the responsible regulatory agency, listing the terms and conditions, including a schedule or prices, under which utility services will be provided.
  • Tax Credits : Credits established by the federal and state government to assist the development of the alternative energy industry.
  • Three Phase Line : This is capable of carrying heavy loads of electricity, usually to larger commercial customers.
  • Time-of-Use Rates : Electricity prices that vary depending on the time periods in which the energy is consumed. In a time-of-use rate structure, higher prices are charged during utility peak-load times. Such rates can provide an incentive for consumers to curb power use during peak times.
  • Tipping Fee : A credit received by municipal solid waste companies for accepting and disposing of solid waste.
  • Total DSM Cost : Total utility and nonutility costs.
  • Total Incentives : The incentive a utility offers is expressed as a percentage of the technology cost. The utility can assume any level between 0 and 100 percent. A value greater than 100 percent is possible if the utility decides to pay for all the equipment and give a rebate as an additional incentive. You can calculate the required incentive by setting the participant test to one by using the following formula: Total Incentives = (Technology Costs - Bill Reductions)/2.
  • Total Nonutility Costs : Cash expenditures incurred through participation in a DSM program that are not reimbursed by the utility.
  • Total Resource Cost (TRC) Test : A ratio used to assess the cost effectiveness of a demand-side management program. Although this economic desirability test provides information about the relative merits of different DSM programs, several important issues are not addressed in this analysis. First, this cost-effectiveness test does not indicate the level of program participation that will be achieved. Second, the most cost-effective mix of DSM technologies is not determined by this test because this methodology only evaluates one specific measure at a time. Finally, these tests are static; they do not include a feedback mechanism to account for changes in demand due to the DSM program. The TRC Test measures the ratio of total benefits to the costs incurred by both the utility and the participant. The TRC test is applicable to conservation, load management, and fuel substitution technologies. For fuel substitution technologies, the test compares the impact from the fuel not selected to the impact of the fuel that is chosen as a result of implementing the technologies. The TRC Test includes benefits occurring to both participants and nonparticipants. Benefits include avoided supply costs (I.e. transmission, distribution, generation, and capacity costs). Costs include those incurred by both the utility and program participant.
  • Total Utility Costs : Total direct and indirect utility costs.
  • Tower : A steel structure found along transmission lines which is used to support conductors.
  • Transfer : To move electric energy from one utility system to another over transmission lines.
  • Transformer : A device for changing the voltage of alternating current.
  • Transition Charge : A charge on every customer's bill designed to recover an electric utility's transition or stranded costs as determined by a Public Utility Commission.
  • Transition Costs : Costs incurred by electric utilities to meet obligations, which required the utilities to meet current and future load demand. The utilities ensured sufficient power generating capacity by building additional power plants, whose debts are currently recovered through a regulated rate of return that would not continue in a competitive marketplace. They could be recovered with a special charge during the transition to competition.
  • Transmission : The act or process of transporting electric energy in bulk.
  • Transmission and Distribution (T&D) Losses : Losses the result from the friction that energy must overcome as it moves through wires to travel from the generation facility to the customer. Because of losses, the demand produced by the utility is greater than the demand that shows up on the customer bills.
  • Transmission and Distribution (T&D) System : An interconnected group of electric transmission lines and associated equipment for the movement or transfer or electric energy in bulk between points of supply and points at which it is transformed for delivery to the ultimate customers.
  • Transmission Charge : Part of the basic service charges on every customer's bill for transporting electricity from the source of supply to the electric distribution company. Public Utility Commissions regulate retail transmission prices and services. The charge will vary with source of supply.
  • Transmission Lines : Heavy wires that carry large amounts of electricity over long distances from a generating station to places where electricity is needed. Transmission lines are held high above the ground on tall towers called transmission towers.
  • Transmitting Utility : This is a regulated entity which owns, and may construct and maintain, wire used to transmit wholesale power. It may or may not handle the power dispatch and coordination functions. It is regulated to provide non-discriminatory connections, comparable service and cost recovery. Any electric utility, qualifying cogeneration facility, qualifying small power production facility, or Federal power marketing agency which owns or operates electric power transmission facilities which are used for the sale of electric energy at wholesale.
  • Transparent Price : The most recent price contract available to any buyer or seller in the market.

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