Fast Facts & Reports

Glossary Of Terms

Advanced Coal Technologies - Includes supercritical, ultra-supercritical, circulating fluidized bed, carbon capture and storage and integrated gasification combined cycle technologies.

Ash - Impurities consisting of silica, iron, alumina, and other noncombustible matter that are contained in coal. Ash increases the weight of coal, adds to the cost of handling, and can affect its burning characteristics.

Baseload Capacity - The generating equipment normally operated to serve loads on an around-the-clock basis.

Blackstart capability - The ability of a generating unit or station to go from a shutdown condition to an operating condition and start delivering power without assistance from the electric system.

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.

Cap-and-Trade - A market-based system of limiting emissions in which a limited number of emissions permits are issued in the aggre-gate (cap); these permits are then freely exchanged in markets (trade).

Carbon Capture and Storage (CCS) - The capture, compression, transport and storage of CO2 emissions.

Carbon Dioxide (CO2) - A colorless, odorless, non-poisonous gas that is a normal part of Earth’s atmosphere. Carbon dioxide is a product of fossil fuel combustion as well as other processes. It is considered a greenhouse gas because it traps heat radiated by the earth into the atmosphere.

CCP - Coal Combustion Products.

Chicago Climate Exchange (CCX) - Currently North America’s only legally binding rules-based greenhouse gas (GHG) emissions allowance trading system, and the world’s only global system for emissions trading based on all six greenhouses gases. Members make voluntary commitments to meet annual GHG emission reduction targets; those who reduce below the target have surplus allowances to sell or bank; those who emit above the targets comply by purchasing CCX Carbon Financial Instruments contracts. AEP is a founding member of CCX.

Climate Change - Changes in climate that depart from normal variability, representing significant changes in averages or extremes.

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

CSAPR - Cross-State Air Pollution Rule.

Curtailment Service Providers - A third-party company that provides demand curtailment services for a utility customer that lowers the customer’s rate because the customer has agreed to reduce demand during periods of high usage. The Curtailment Service Provider shares in the customer’s savings.

Customer Choice - Allowing certain customers to purchase electricity from alternative competitive suppliers.

Demand - Rate at which electric energy is delivered to or by a system or part of a system, generally expressed in kilowatts or megawatts, at a given instant or averaged over any designated period of time.

Demand Response (DR) - The planning, implementation and monitoring of utility activities designed to encourage consumers to modify their patterns of electricity usage.

Dry-Cask Storage - a storage system for used nuclear fuel.

Emissions - Anthropogenic releases of gases to the atmosphere. In the context of global climate change, they consist of greenhouse gases.

Energy Efficiency - Refers to programs that are aimed at reducing the energy used by specific end-use devices and systems, typically without affecting the services provided. These programs reduce overall electricity consumption (reported in megawatt hours), often without explicit consideration for the timing of program-induced savings. Such savings are generally achieved by substituting technically more advanced equipment to produce the same level of end-use services (e.g., lighting, heating, motor drive) with less electricity. Examples include high-efficiency appliances, efficient lighting programs, high-efficiency heating, ventilating and air conditioning (HVAC) systems or control modifications, efficient building design, advanced electric motor drives and heat recovery systems.

ESP - Electric Security Plans mandated by restructuring legislation enacted in Ohio that utilities submit detailing the rates they will charge.

Extra-high Voltage (EHV) - The electric utility industry generally considers EHV to be any voltage of 345 kV or higher.

Fossil Fuels - Hydrocarbon fuels derived from fossils: specifically coal, petroleum and natural gas.

Fuel Factor - The component of an electric bill that recovers the cost of fuel used to generate electricity.

GAAP - Generally Accepted Accounting Principles.

Greenhouse Gas (GHG) - Collective term for gases such as carbon dioxide that trap heat in the atmosphere and contribute to climate change.

Grid - An interconnected network of electric transmission lines and related facilities.

Independent System Operator - An independent, federally regulated entity that coordinates regional transmission in a non-discriminatory manner and ensures the safety and reliability of the electric system.

Kilowatt - One kilowatt equals 1,000 watts.

Kilowatt-hour - The basic unit of electric energy equal to one kilowatt of power supplied to or taken from an electric circuit steadily for one hour. One kilowatthour equals 1,000 watthours.

LEED - a standard for green building design, maintenance and operation. LEED stands for Leadership in Energy and Environmental Design and is a program of the U.S. Green Building Council.

Load - An end-use device or customer that receives power from the electric system. Load should not be confused with demand, which is the measure of power that a load receives or requires.

MATS - Mercury Air Toxics Standards rule.

Megawatt - One megawatt equals 1 million watts.

Nitrogen Oxide (NOx) - Gases formed in great part from atmospheric nitrogen and oxygen when combustion takes place under conditions of high temperature and high pressure; considered a major air pollutant.

Ongoing Earnings - earnings based on the company’s business apart from special charges or one-time accounting adjustments.

OpCo - This is an acronym AEP uses to describe its operating companies.

PCB - Polychlorinated Biphenyl (PCB), is a coolant commonly used in electrical equipment, now classified as a persistent organic pollutant. Production was banned in the United States in 1979, but it is still found in older equipment.

Plant Efficiency: - The percentage of total energy content of a power plant’s fuel that is converted into electricity. The remaining energy is lost to the environment as heat.

Portfolio Standards - Guidelines or requirements that total electricity supply include one or more set minimum for particular sources, such as renewable energy.

Pumped Storage - The only method now in commercial use for large-scale storage of electricity. Excess electricity produced at times of low demand is used to pump water into a reservoir. At times of high demand, this water is released and used to operate hydroelectric generators to produce supplemental electricity. Pumped hydroelectric storage returns only about two-thirds to three-fourths of the electricity put into it, but it costs less than an equivalent amount of additional generating capacity.

Rate-making Authority - A utility commission’s legal authority to fix, modify, approve or disapprove rates, as determined by the powers given to the commission by a state or federal legislature.

Reconductoring - Reconductoring is the replacement of the conductors of a transmission line currently in service with new conductors.

Reliability - The degree of performance of the elements of the bulk electric system that results in electricity being delivered to customers within accepted standards and in the amount desired. Reliability may be measured by the frequency, duration and magnitude of adverse effects on the electric supply. Electric system reliability can be addressed by considering two basic and functional aspects of the electric system — adequacy and security.

Renewable Energy Resources - Energy resources that are naturally replenishing but flow-limited. They are virtually inexhaustible in duration but limited in the amount of energy that is available per unit of time. Renewable energy resources include: biomass, hydro, geothermal, solar, wind, ocean thermal, wave action and tidal action.

Retail Competition - The concept under which multiple sellers of electric power can sell directly to end-use customers and the process and responsibilities necessary to make it occur.

Retail Electric Provider - An energy-only service, providing energy sales to ultimate customers, where delivery service is provided by a utility. Services may also include metering, billing or power quality enhancement. Also referred to as alternative energy provider and energy service provider.

SAIDI - System Average Interruption Duration Index, a measure of the average length of an outage.

SAIFI - System Average Interruption Frequency Index, a measure of how often outages occur.

Securitization - A method of raising capital by issuing a security that conveys the rights to the proceeds or revenues associated with a particular asset. In this way, a company essentially may sell its rights to receive certain future revenues in order to obtain funds on a current basis. The purchaser of the securitized asset generally would not have a future claim on all of the assets of the company but instead would obtain all of its returns from the specific asset or revenue source specified in the security.

Supercritical Generation - a type of generation at which water is heated at high pressure (3,500 psi or higher) and high temperature (1,000 to 1,050 degrees) to convert it to steam more efficiently than boiling.

Transmission System - An interconnected group of electric transmission lines and asso-ciated equipment for moving or transferring electric energy in bulk between points of supply and points at which it is transformed for delivery over the distribution system lines to consumers, or is delivered to other electric systems.

Ultra-Supercritical Generation - Ultra-supercritical generation is a new, efficient, pulverized coal technology requiring less coal to produce the same amount of power as existing plants using Powder River Basin coal.

Wholesale Sales - sales of electricity to other utilities or to public authorities for resale distribution (except under exchange agreements).

Wind power plant - A group of wind turbines interconnected to a common utility system through a system of transformers, distribution lines and (usually) one substation.

Source:  Edison Electric Institute

AEP Central Machine Shop

At the Central Machine Shop (CMS) in South Charleston, WV, an AEP employee performs a magnetic particle inspection of blades used on a 1,300-MW low-pressure turbine rotor.

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