NRG Electricity Glossary for Customers

Electricity Glossary for Customers

Make sense of your Reliant electric bill and get a better understanding of how electricity works in your home with these definitions of commonly used terms.

Electricity Bill Terms 

Account number
The unique number assigned to each Reliant account.

Account summary
The section of your bill containing your previous payment amount, balance forward, current charges and current amount due.

Amount due
The amount you owe from your current bill.

Balance forward
The difference between the previous amount due and the payment you made on your last bill. You still owe us this amount, and the balance is due right away (not when your current bill is due). If you paid this amount after the bill was generated, it will still appear on your bill.

Base charge
A charge assessed during each billing cycle without regard to the customer’s demand or energy consumption.

Billing date
The date your bill was generated.

Billing period
The dates for which you were billed.

Billing statement
The statement that includes all charges for a specific billing period, another term for bill.

Connection fee
A fee charged by your transmission and distribution service provider (TDSP, your area's poles/wires or utility company) to connect and start electric service at a particular address.

Deferred payment plan
The agreement that allows eligible customers to pay their outstanding balance in installments.

Demand charge
Charge based on the rate at which electricity is delivered to your system at a particular instant or averaged over a designated period in the billing cycle. Typically, the energy demand for your business or residence is determined by finding the highest amount of electricity your property uses and maintains for 15 minutes. This is measured so power generators know how much electricity needs to be available for all locations on the grid. A demand charge is used more typically for businesses than for residential addresses.

Disconnect/reconnect fee
A fee charged by your TDSP (e.g., your area's poles/wires or utility company) to disconnect or reconnect electric service.

Disconnect notice fee
A fee charged by Reliant to cover the cost of creating, printing and mailing the disconnection notice. 

Disconnect recovery charge
Charge applied if you are issued a disconnection notice and do not pay your past due charges before the date when you are subject to disconnection. This fee applies regardless of whether your service is actually disconnected.

Electricity usage
On your electricity bill, this is the amount of electricity used in a billing cycle, measured in kilowatt-hours (kWh).

Energy charge
The amount of electricity you used in kWh multiplied by the price you pay per kWh.

Gross receipts tax reimbursement
If you live in an incorporated town or city with more than 1,000 residents, we assess this fee to recover the gross receipts tax imposed on retail electric providers.

Invoice number
The unique number assigned to each specific bill.

Kilowatt (kW)
A standard unit that measures electrical energy (1,000 watts = 1 kW).

Kilowatt hour (kWh)
A unit or measure of electricity supply or consumption equaling 1,000 watts operating for one hour. Ex: 1 kWh = ten 100 watt bulbs all burning at the same time for one hour; 10 bulbs x 100 watts each x 1 hour = 1 kWh

Late payment

A payment that is past due.

Payment
On your bill, the most recent payment we've received.

Payment slip
A section of the bill you can tear off and return with your check or money order for the amount due.

Prepaid plans
Prepaid electricity plans provide electricity service on a pay-as-you-go basis. These plans allow customers to decide how much electricity to purchase, as opposed to a traditional plan that delivers a bill at the end of a billing cycle.

Previous amount due
The amount due from your previous bill.

Price
The amount you pay per kWh for electricity on your plan — includes all recurring charges and excludes state and local sales taxes, non-recurring charges or credits, and reimbursement for the state miscellaneous gross receipts tax. The amount of electricity you use is multiplied by the price to calculate your energy charge.

TDSP delivery charges
The cost of delivering electricity to your home, charged by your transmission and distribution service provider (TDSP). All delivery charges are approved by the Public Utility Commission of Texas and apply to all residential customers within a TDSP's service area, regardless of electricity provider.

Usage
The amount of electricity you used during a specified billing period listed in kilowatt-hours (kWh). This is listed on your electric bill as kWh used.

Usage charge
A charge assessed during each billing cycle according to the terms of your electricity plan.


Electricity Industry Terms 

Circuit
The complete path electricity follows from a source through a connection to an output device. For example: A circuit can be made from a battery (source) through a copper wire (connection) to a light bulb (output device) and back to the battery.

CFL (compact fluorescent light bulb)
A fluorescent lamp compressed into the size of a standard-issue incandescent light bulb that’s designed as an energy-efficient replacement. Compared to incandescent lamps that produce the same amount of visible light, CFLs typically last at least six times as long and use at most a quarter of the energy of an equivalent incandescent bulb. Conductor An object that permits an electric charge to flow easily. Examples of conductors are metal, salt, water and wool.

Customer choice/electricity choice
In deregulated retail electricity markets like Texas, customer choice means you can choose a retail electricity provider (REP) and an electricity plan to meet your specific needs. While just one company maintains the poles and wires that deliver your electricity, many companies compete to sell you the electricity that runs over the poles and wires. As a result, you get to choose the type of plan and REP you prefer.

Deregulation (electricity deregulation)
The move from a regulated electricity system, where customers may not have a choice about which electricity company they use, to a competitive electricity market. Electricity deregulation means you can choose a retail electricity provider (REP) and an electricity plan that meet your specific needs. One company (your TDSP) maintains the poles and wires that deliver your electricity, but many companies compete to sell the electricity that runs over the poles and wires.

Distributed renewable generation (DRG)
On-site, customer-owned renewable power systems, such as solar panels or wind turbines, that supply a portion or all of a customer's electricity requirements. These systems are typically connected to the power grid and can send excess electricity into the grid.

Electric current
A measure of the amount of electrical charge transferred per unit. It represents the flow of electrons through a conductive material. A common unit of current is the ampere.

Electric energy
The ability of an electric current to produce work, heat, light or other forms of energy. It is measured in kilowatt hours.

Electric Reliability Council of Texas (ERCOT)
The state’s largest electricity management agency that oversees the electric grid. ERCOT serves 23 million Texas customers, representing 85% of the state’s electric load and 75% of the state’s land area.

Electric service identifier (ESID)
A unique 17- or 22-digit number number in the ERCOT market given to an electricity delivery point by the TDSP, usually visible on your electric meter. You can find this number on your Reliant electricity bill (second page, in the Account Information section) or in your online Reliant account (on your Plan page, under the plan name). (Same as ESI I.D. below.)

Electric utility
An electric power company, often a public utility, which engages in the generation, transmission and distribution of electricity.

Electrical grid
A network of transmission and distribution lines, substations and transformers that delivers electricity to consumers.

Electricity
The supply of electric currents to a house or other building for heating, lighting or powering appliances.

Electricity demand
The amount of electricity being consumed at any given time. Demand rises and falls throughout the day in response to the time of day and other environmental factors.

Electricity facts label (EFL)
A document required by the Public Utility Commission of Texas that provides customers with information on pricing, contract length, cancellation fees, sources of power generation and emissions along with other disclosures in a standardized format. 

Electricity generation
The process of producing electricity using a natural resource or a renewable source, such as coal, natural gas, nuclear energy, solar, wind, water or biomass.

Emergency backup generation
Alternative means of generating electricity used only during temporary interruptions of normal power supply.

Energy audit
A review of your home or place of business to find out how much energy you are using and identify ways to reduce energy usage. The audit could be performed in person or by reviewing energy usage data for your residence or business property.

Energy charge
A portion of your total charge for electricity service; the total number of kilowatt-hours consumed within the billing cycle times the price you pay per kWh.

Energy efficiency
Using less energy to provide the same level of performance, comfort and convenience. The goal of energy efficiency is to reduce energy use, which may result in cost savings and the conservation of natural resources.

EnergyGuide Label
Yellow and black labels found on appliances that can help you compare the energy use of similar models while you shop. The Federal Trade Commission's Appliance Labeling Rule requires appliance manufacturers to put these labels on:

  • Refrigerators, freezers, dishwashers, clothes washers, televisions
  • Water heaters, furnaces, boilers, heat pumps
  • Central air conditioners, room air conditioners
  • Pool heaters
  • Certain light bulbs, plumbing products and ceiling fans

Energy source
The primary source used to generate power. The energy could be converted to electricity through chemical, mechanical or other means. Common energy sources include coal, petroleum, gas, water, uranium, wind, sunlight, geothermal, etc.

ENERGY STAR®
ENERGY STAR is a U.S. Environmental Protection Agency program that helps individuals and businesses identify energy saving products. Products that earn the ENERGY STAR label are independently certified to save energy without sacrificing functionality.

ESI I.D. (electric service identifier)
A unique 17- or 22-digit number number in the ERCOT market given to an electricity delivery point by the TDSP, usually visible on your electric meter. You can find this number on your Reliant electricity bill (second page, in the Account Information section) or in your online Reliant account (on your Plan page, under the plan name). (Same as electric service identifier above.)

Fixed rate
You pay a certain rate for electricity, usually per kilowatt hour (kWh) of usage, each billing cycle. On a fixed rate plan, the price you pay per kWh will stay the same for the duration of your contract. This is different from a variable price plan, where the price can change from one billing cycle to the next.

Generation
The production of electricity. In Texas, electricity is produced using a number of energy sources, including natural gas, coal, nuclear power, wind, water and solar energy.

HVAC
An abbreviation for the heating, ventilation and air-conditioning system, which is the system or systems that condition air in a building.

Incandescent light bulbs
An incandescent light bulb or lamp is a source of electric light produced by a filament heated by an electric current. Governments around the world are phasing out incandescent light bulbs in favor of more energy-efficient lighting alternatives, such as compact fluorescent light bulbs (CFLs).

Local wires company
The company that transmits and delivers electricity to a customer's home or business along the electrical poles and wires. The local wires company is responsible for maintenance and repair of these poles and wires and is also referred to as the transmission and distribution service provider (TDSP).

Lumens
A unit of measurement of light energy. Specifically, lumens measure the amount of light a lamp produces in all directions.

Meter
A device that measures the amount of electrical energy consumed by a residence, business or an electrically powered device. Utility companies (or TDSPs) read meters to determine how much electricity each customer used. Types of electricity meters include digital meters and smart meters.

Off peak
A period of relatively low system demand for electricity. These periods often occur in daily, weekly and seasonal patterns. The use of smart meter technology has allowed electricity companies to offer new products that take advantage of off-peak pricing periods

On peak
Periods of relatively high system demand for electricity. These periods often occur in daily, weekly and seasonal patterns.

Public Utility Commission of Texas (PUC or PUCT)
The state agency responsible for the regulation and oversight of electricity and local telecommunication services in Texas. In Texas' deregulated market, the PUC still regulates the delivery of electricity and enforces customer protections.

R-value
A measure of the resistance of an insulating or building material to heat flow, expressed as R-11, R-20 and so on. The higher the R-value, the greater the resistance to heat flow and better insulating capability.

Radiant barrier
A thin, reflective foil sheet that reflects radiant heat back to its source. Typically installed in attics or as a house wrap, radiant barriers reduce summer heat gain and winter heat loss—resulting in a reduction in energy usage.

Renewable energy
Electricity made from resources that rely on fuel sources that naturally regenerate over a short period of time, such as the sun, wind, moving water, biomass or biomass-based waste products, or the earth’s heat (geothermal). A renewable energy technology does not rely on energy resources derived from fossil fuels, waste products from fossil fuels, or waste products from inorganic sources.

Retail electric provider (REP)
In Texas, a REP is a company that sells electricity to consumers and is responsible for sending a monthly electricity bill.

Smart meter
A type of electricity meter that has continuously available, remote, two-way communication and information storage capability. Smart meters record and store your electrical usage in 15-minute intervals and communicate that usage information back to your local wires company. Unlike traditional electric meters that only measure total consumption, smart meters show when the energy was consumed.

Transformer
A device used to transfer electric energy from one circuit to another.

Transmission and distribution service provider (TDSP)
The local wires company responsible for the poles and wires that transmit and deliver electricity to your home or business. TDSPs are responsible for the maintenance and repair of these poles and wires.

Total current non-electricity charges
The total charge for other products or services you have signed up for, such as protection plans or Reliant EcoShare.

Variable price
On a variable price electricity plan, the rate you pay may go up or down depending on monthly changes in the marketplace.

Volt
A unit that measures the force used to produce an electric current. Also the push or force that moves electric current through a conductor.

Watt
A unit that measures electric power. 1 kW = 1,000 watts. 1 Megawatt (MW) = 1,000,000 watts 

Wattage
The rate of electric energy being used by lights or appliances.

Wind turbine
A device that converts kinetic energy from the wind, also called wind energy, into mechanical energy in a process known as wind power.

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