Texas Electricity Glossary for Homes and Businesses

Here’s an extensive Electricity Glossary that includes standard definitions of electricity terms and definitions for the Texas electricity market.

With this glossary, you’ll be able to speak with electric companies, brokers, and consultants about your home and business electricity needs.

For best results, use the glossary in tandem with the following guides to help you choose the right electric company and energy plan:

Advanced Metering Infrastructure — The technology used by utilities, businesses and residential customers to communicate with smart meters.

Aggregator — A firm that aggregates Texas home electricity and business customers, and combines their electricity loads to bargain with energy providers for advantageous rates.

Alternating current (AC) — A type of electric charge which reverses direction in an electric conductor.

Amps — The abbreviation for ampere, which is the basic unit of electric current flow in an electric circuit,  denoting electric current equivalent to a flow of one coulomb per second.

Apparent power: The combination of real and reactive power, and the product of voltage and current of the circuit. It’s measured in volt-amps (VA).

Battery — A device used as a source of power that consists of one or more electrochemical cells that convert chemical energy into electricity. Battery technology advancements will be a key factor in improving the economics of alternative energy sources and electric vehicles.

Biofuel — A non-fossil, renewable fuel used to produce energy. Biofuels represent a relatively small percentage of renewable energy supply.

Blackout — Power outage that occurs in transmission systems that are corrected by Transmission and Distribution Utility companies in Texas. It’s important to know who to call in case of a power outage in Texas.

Capacitor — One or more pair of conductors separated by an insulator which is used to store an amount of electric charge, and is used to regulate voltage and enhance power factor.

Capacity — The maximum amount of electrical power that transmission systems can process.

Carbon dioxide (CO2) — A major greenhouse gas produced by the burning of organic compounds like fossil fuels. It is also exhaled by humans during respiration and is used by plants for photosynthesis. Carbon dioxide is a major contributor to climate change. See a renewable energy solution to rid the electric grid of carbon sourced electricity to combat climate change.

Circuit — The route taken by electrons to flow through a conductor. The path must begin and end at the same point, and the circuit consists of a conductor, load and electricity flow.

Circuit breaker — An automatic device that interrupts the flow of electricity, used generally as a safety measure.

Climate Change – The disruption and warming of the environment as a result of the release of carbon emissions into the atmosphere. See a renewable energy solution to climate change.

Coal — A fossil fuel that is used in the generation of electricity, and produces CO2.

Cogeneration — The process that utilizes the power of leftover steam or hot water from electricity generation to produce additional electricity.

Combined heat and power — A power station that uses cogeneration, or the process of producing electricity and heat from a single fuel source.

Conductor — A wire in an electric grid that allows the passage of electrical carriers when electrons move from atom to atom.

Current — The rate of flow of electrons through a conductor in a directional movement. It is usually measured in amperes (amps).

Customer choice — The legislated right of a residential or business customer to purchase electricity from an electric company of their choice, in a deregulated energy market.

Delivery point — The end point where electricity is transmitted and delivered in a transmission system or circuit.

Demand charge — The amount an electricity customer is charged in relation to the maximum demand created by the customer’s load in a period of time.

Demand response — Incentives that allow electricity customers to decrease their their electricity demand in return for financial benefits.

Demand side management — Reducing the demand for energy, especially during peak periods, by the management of pricing and public awareness.

Direct current (DC) — A current of electricity that moves in a single direction in a conductor.

Distribution — The transmission of electricity over a transmission and distribution system to customers by TDU’s in Texas.

E-gallon — A metric for comparing the cost of driving an electric car to what you’d spend on regular gas to go the same distance, sometimes referred to as MPGe.

Electric car charger — A power supply device which supplies electrical power for recharging plug-in electric vehicles. Examples include a Level 2 charger and a DC fast charger. See our electric vehicle guide for more information.

Electricity — Energy generated by the movement of electrons in a conductor.

Electricity demand — The maximum amount of electricity that is being consumed at a given time, measured in kilowatts (kW).

Electricity rate — The price for electricity per kWh charged by a retail electricity provider (REP). Compare electricity rates in Texas from the largest electric companies.

Electricity plan – An energy rate plan offered by a retail electricity provider, the details of which are reflected in the State of Texas Electricity Facts Label.

Electrical power — The rate at which electrical energy is transferred from one point to another, measured in watts.

Energy Deregulation — The process of removing government regulatory control in the retail energy market and providing consumers the ability to choose their electricity provider in the Texas deregulated electricity market.

ERCOT (Electric Reliability Council of Texas) — The entity providing electric operations to deregulated electricity areas in Texas.

EV (electric vehicle) — A vehicle that uses one or more electric motors for propulsion.

Extended range electric vehicle — A type of electric vehicle which runs on electricity alone, but also has a gasoline-powered generator that kicks in when the battery runs low.

Fuel cell — An electrochemical cell that converts chemical energy to electricity from an external fuel source.

Forward market — The delivery of electricity purchased in advance.

Fossil fuel — Fuel produced by natural processes in the decomposition of organic matter. Fossil fuels include natural gas, oil and coal, which are used as source fuels in the generation of electricity. See the equivalencies  of CO2 emissions associated with fossil-sourced energy plans.

Generator — A power plant that produces electric power that feeds into the electric grid and is transmitted to homes and businesses.

Geothermal Energy — Geothermal energy is a renewable resource harnessed from heat produced deep in the Earth’s core.

Green energy (renewable energy) — electricity produced from renewable sources of energy and offered in Texas electricity plans by energy providers, such as wind and solar power plans.

Greenhouse gas — Gases such as carbon dioxide (CO2) and methane, which in excessive quantities result in the entrapment of energy in the atmosphere, warming the Earth’s surface. The emission of these gases is in large part due to the burning of carbon-sourced fuel, including the burning of coal and natural gas to operate electric generation plants.

Grid — The electricity transmission and distribution system, operated in Texas by Transmission and Distribution Utilities (TDUs).

Grid parity — the price point at which fossil-sourced energy is the same as that of renewable energy.

Heat rate —  A measure of the efficiency of power plants which is checked by determining the amount of fuel required to generate a certain amount of electricity, expressed as Btu/kWh.

Hybrid electric vehicle — A type of vehicle that runs primarily off of fuel. However, it has an electric battery that’s recharged through regenerative breaking. It cannot be plugged into an electricity source though, and relies entirely on fuel for energy.

Hydrocarbon —  An organic compound made of hydrogen and carbon, and chief components in petroleum and natural gas.

Hydroelectric power — Electricity generated with the use of water.

Index energy plan— A type of electricity plan based on a calculation of the average price of electricity during a period of time.

Interruptible rate plans — Electricity rate plans offered by retail electric companies in which an end user (usually a business entity) forgoes the use of electricity at certain times in return for a financial benefit.

Kilovolt-amps (kVA) — A measurement unit equal to 1000 volt-amperes.

Kilovolt (kV) — A measurement unit equal to a thousand volts.

Kilowatt-hour (kWh) — A measure of electricity which is equivalent to the power consumption of one thousand watts in an hour. It’s the measurement of electricity used by a home or business as shown in monthly energy bills and as displayed in the Texas Electricity Facts Label (EFL).

Kilowatt (kW) — A measure of electrical power equivalent to one thousand watts. The usage levels of 500 kWh, 1000 kWh and 2000 kWh are used in the Texas EFL for each energy plan.

Load — The electricity demand of an end user.

Load factor — The amount of electricity used over a specific period compared to the amount an end user would have consumed over the same period at maximum demand.

Megawatt-hour (MWh) — A measure of electricity which is equivalent to 1,000 kilowatt-hours.

Megawatt (MW) — A measure of electrical power which is equivalent to 1 million watts or 1,000 kilowatts.

Meter — A tool that is used to measure the amount of electricity consumed by any electrically powered system.

Municipal utility — A utility operated by a municipality for the benefit of its citizens.

Nuclear power — The electricity generated by the heat of nuclear fission in nuclear reactors.

Ohm (Ω) — A unit of electrical resistance in an electrical circuit.

Ohm’s Law — Physical law that states the current which passes between two points in a conductor is directly proportional to the voltage between those two points.

Peak electric demand — The maximum electrical power demand in an electrical grid in a given amount of time.

Photovoltaic cells — An electrical device that converts energy produced by light into electricity. 

Plug-in electric vehicle — A type of EV that runs solely on electricity and requires a plug-in EV charger to be recharged.

Plug-in hybrid vehicle — A type of EV that runs primarily off of electricity but also has a fuel engine which you can switch to if your car’s battery runs out of charge.

Power factor — The ratio of the actual power dissipated by real power to the root mean square of apparent power in an electrical circuit.

Promo codes — Alphanumerical marketing codes issued by electric companies that provide a discount off of their regular rates when used at the time of enrollment in an energy plan. Also known as promotional codes, referral codes, discount codes and coupon codes. Promo code pages on comparison websites, and special promo code websites such as Energy Promo Codes provide codes for major energy companies.

Real power — The power consumed in an AC circuit measured in kilowatts (kW).

Reliability of electricity — A measure to determine the ability of a power system to deliver uninterrupted, reliable power.

Renewable energy — Electricity that is generated from renewable sources of energy and offered in 100% renewable “green” energy plans. In Texas, wind and solar power are the dominant sources of renewable “green” energy.

Renewable Energy Certificate (REC) — Tradable commodities in the energy market, each of which symbolizes a single MWh of electricity created and fed into the grid from an acceptable renewable energy source.

Residential electricity customer — A customer of electricity who is a homeowner, or an apartment or condo inhabitant.

Resistance: The measure of opposition to the flow of electric current through a conductor, quantified in ohms.

Retail Electricity Provider (REP)— A business that buys electricity in blocks, and then resells it direct to residential and commercial consumers. See listings of many retail electricity providers in Texas, also known as electric companies, light companies and energy providers.

Rural electric cooperative — A customer-owned utility entity servicing a rural area. Metropolitan markets in de-regulated electricity zones in Texas include Houston and Dallas.

Single-phase power — Production of power utilizing a single coil of wire in a generator.

Smart meter — An electronic metering device that communicates data remotely to a utility company for monitoring and billing of electricity. Smart Meter Texas provides homeowners access to usage information from smart meters in Texas.

Solar electricity — A power source that utilizes the energy from the sun and converts it into electricity, either directly using photovoltaics or indirectly using concentrated solar power.

Solar panel — A device that converts sunlight into electricity by using photovoltaic cells. Check out our solar panel installation guide for more information.

Substation — An electrical system for transmission and distribution of electricity which modifies levels of voltage and direct flow.

Supply of electricity — The quantity of electricity available for the electric grid.

Supplier — marketer of electricity and natural gas, also called electric company, energy provider, light company, power company. See the energy supplier brands and find their cheapest energy plans here.

Switchyard — An enclosed area of an electrical power system that contains the switchgear and transformers which connect the power plant to the transmission and distribution system.

System peak — The maximum load of power demanded from an electric system in a fixed amount of time.

Tariffs — The rates and fees approved by the government that a utility can charge customers. You can find rate information for each energy provider and the associated TDU charges in the Electricity Fact Label for each energy plan.

Texas Public Utilities Commission (PUC) — The State of Texas governmental agency that regulates retail energy providers (also called electric companies and light companies), as well as transmission utilities and aggregators/brokers.

Three-phase electric power — The most commonly used method for power generation, using a type of polyphase system which has three separate voltages operating at different timings through an independent conductor.

Three-wire electric service — A single phase electric service to an end user facility consisting of three conductors, in which the center one is grounded.

Time-of-use meter — Measures and records energy consumption of a customer based on the time when electricity is used. You’ll find time-of-use energy plans made possible by smart meter technology and used for homes, apartments/condos and electric vehicles; these plans are often marketed as “free” electricity plans, as they provide electricity at no cost at certain times of day (see the pros and cons of free electricity plans in this shopper’s guide).

Transformer — An electrical device that is used to convert alternating current from one voltage to another.

Transmission — The large-scale movement of electricity from the generator to the distribution system.

Transmission line — A wire conductor that carries electric power with voltage greater than 50 kV.

Transmission and Distribution Utility (TDU, also called TDSP) — The regulated utility company that maintains the wires and lines, checks meters and corrects outages. For example, in Houston, the TDU is Centerpoint and in Dallas the TDU is Oncor, as well asAEP, TNMP and Sharyland.

Turbine — A machine with propeller-type blades that rotate with the movement of air, liquids, and gas to harness their kinetic energy to produce usable forms of energy. Wind energy facilities in Texas use turbines to produce renewable energy.

Usage of electricity — Energy consumption measured in kWh, as reflected in residential energy bills. Texans can conveniently find the historic electricity usage for their homes at Smart Meter Texas.

Volt — An electrical unit measure of voltage.

Voltage — The potential difference in charge between two points in an electrical field, it moves electricity through electric conductors.

Watt — The unit to measure of power defined as the rate of consumption of energy of one joule per second.

Wind energy — A power source which converts the kinetic energy that wind produces into electricity to help power the grid.


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