GLOSSARY

To help you understand the terms used by the electricity industry, we have provided definitions to some common electricity-related terms. If you have a question about Waterloo North Hydro, please read the information provided in “Stay Informed.”

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Aggregator / Broker / Marketer / Retailer
A company that sells electricity or arranges transactions between or on behalf of electricity generators and customers.

Amp
Measures the quantity of electric current. Short for ampere (A).

Arcing (gapping)
The flow of electricity through the air from a conductor to another object that conducts electricity. Produces visible flashes and flames and a crackling sound.

Arrester (surge, lightning)
A protective device installed on the primary (high voltage) side of the distribution transformer used to prevent excessive over-voltage surges across the transformer, caused by lightning strikes or live-line switching.

Bus
A rigid, large conductor, usually used in substations, to provide a quick, convenient means of rearranging circuit connections to keep power flowing or to restore power in case of equipment damage.

Cable Chamber
A below-grade opening to the underground duct system, which facilitates the installation and removal of cables, and provides access to cables requiring inspections and repair. Also for making cable splices and joints.

Cable Fault
A hole in a cable caused by a short circuit (due to corrosion, overloading over time, water, age), which can result in an explosion. Faults can occur at joints in cable chambers or in ducts between the chambers. Crews use "fault finding equipment" to locate and repair underground cable faults.

Capacitor
Installed in substations and on poles to help improve the efficiency of lines to carry electrical power by reducing energy losses.

Circuit
A system of conductors providing a path for electricity.

Circuit Breaker
An overcurrent protective switch in a substation that automatically disconnects power to the circuit in the event of a fault condition. Is similar to a circuit beaker found in a home.

Current Limiting Fuse
A device that limits the amount of fault current flowing into the fault.

Cutout (or Fused Cutout)
A protective device installed on the primary side of the distribution transformer. Used to prevent short-circuit currents from damaging the transformer itself or the secondary lines that are connected to the low-voltage side of the transformer. Cutouts are also used as switches to isolate the transformer or a single-line primary run-off to effect repairs on them.

Current
The flow of charge in an electrical circuit. Current is measured in amperes (Amps).

Debt Retirement Charge (DRC)
To pay off the residual portion of the former Ontario Hydro's “stranded debt,” electricity customers in the province pay something called the Debt Retirement Charge. This item appears on every electricity bill and is billed at .07 cents per kilowatt-hour

Distributor, or Local Distribution Company (LDC)
A distributor is responsible for safely delivering electricity through the local wires to electricity customers in a specific area or community. Electric utilities are referred to as Local Distribution Companies or LDCs.

Distribution Transformer
A large piece of equipment required for reducing the distribution primary voltage to the secondary voltage, thereby matching the customers’ appliances and equipment voltages.

Elbows
Used to terminate cables in vaults and in padmounted transformers. They can come in loadbreak and in deadbreak types.

Energy
The capacity to do work. Forms of energy include light, heat, sound, mechanical and electrical.

Feeder
A distribution circuit carrying power from a substation. The heavy high-voltage cable (circuit) supplies the distribution transformers and emanates from the station via ducts beneath city streets to the designated service areas.

Feeder Lockout
The main circuit is interrupted at the substation by automatic protective devices and cannot be restored until crews investigate. Usually indicates a serious problem on the circuit, either a broken conductor or other equipment failure.

Fuse
Protects the distribution line from overloading. Acts by melting during overloading or faults, breaking the circuit. Is similar to fuses found in fuse boxes in homes.

Ground
When one or more conductors contact the earth, causing the electricity to flow out of the circuit into the earth.

Hourly Spot Price
This is the hourly price for electricity in the IMO administered wholesale electricity market. This price changes from hour to hour, day by day, season to season. Wholesale sellers (generators) submit offers and wholesale buyers (loads) submit bids for electricity in different quantities and prices for each hour. The IMO calculates the spot price by balancing the supply of electricity with demand. As demand increases, buyers submit higher bids, which raises the spot price. As demand falls, only less expensive offers from sellers are accepted, and prices drop.

Hydro One
One of the commercial Ontario Hydro successor companies. Its largest subsidiary company owns the central transmission grid and is also a major, growing distribution company. Other subsidiaries of Hydro One sell electricity, telecommunications and other services.

Independent Electricity System Operator (IESO)
This is another Ontario Hydro successor company. It's responsible for ensuring an adequate supply of power for the province, operating its electricity market, and ensuring the safety and reliability of the electricity grid.

Kilowatt-hour (kWh)
The amount of energy transferred by one kilowatt of power in an hour.

Limiters
Low-voltage fusible devices connected to each end of a secondary cable run. Their purpose is to prevent excessive cable damage and possible chamber fires caused by sustained secondary cable faults.

Megawatt
A Megawatt equals 1,000 kilowatts or enough to power 10,000 100-watt light bulbs.

Ontario Energy Board (OEB)
The OEB is the regulator that licenses industry participants, establishes operational codes, regulates the rates for transmission and distribution, approves sales or purchases of regulated utilities and investigates customer complaints, both for electricity and gas.

Ontario Power Generation Inc. (OPG)
One of Ontario Hydro's commercial successor companies, it owns most of the former Ontario Hydro generating plants: gas fired, coal fired, hydro electric and nuclear power stations.

Payments in lieu of taxes (PILs)
These are forms of proxy taxes paid by government owned bodies. Among the new PILs that have been imposed by the Act, some are approximately equal to federal and provincial corporate income and capital taxes. This money goes towards paying down the stranded debt. Municipal and provincially owned companies will continue to pay municipal tax to the municipality.

Performance Based Regulation (PBR)
This is the form of regulation the OEB uses for setting distribution and transmission rates. It focuses on performance, rather than costs.

Pothead
Used to terminate paper-insulated lead-covered cable.

Power
The rate at which energy is transferred, or converted into work. It is usually measured in watts.

Provincial Benefit
The price of generation in Ontario is set by a competitive market. Certain generators receive payments through regulation or contract that differ from the market price. Your portion of the net adjustment arising from these different payments is included on your bill.

Residual Stranded Debt
The portion of the stranded debt that is not covered by dividends and PILs. It is financed by a Debt Retirement Charge, currently set at 0.7 cents / kWh, to be added to customers' bills until the Residual Stranded Debt is paid off.

Riser
An assembly of components that enables the underground feeder cables to emerge from below grade and be brought up a pole for connection to the overhead lines.

Secondary Cables (or Mains)
Underground low voltage (<750 volt) cables that are connected to the secondary side (low voltage) of the distribution transformer and delivers the current to customers.

Stranded Debt
This is a term for the total debt and liabilities accumulated by the former Ontario Hydro, less the debt assumed by successor companies (Ontario Power Generation, Hydro One). The stranded debt is held by the Ontario Electricity Financial Corporation, and is to be paid down in several ways through payments in lieu (PILs) from successor companies and municipal Hydro successor companies, and through the Debt Retirement Charge.

Switch
A device for isolating a piece of equipment or a section of feeder to allow repairs or replacements to be made on them while in a de-energized state.

Transformer
A device used to transform voltage levels to facilitate the transfer of power from the generating plant to the customer. A step-up transformer increases the voltage while a step-down transformer decreases it.

Transformer Vault
There are two types of transformer vault (walk-in or below-grade), which are used to: (1) house submersible transformers, switches and protective equipment (fuses and surge arresters), and (2) provide adequate working space for personnel to install and remove equipment and to effect various inspections and maintenance duties

Tree Wire
A covered conductor used in heavily treed areas to provide some protection form momentary tree limb contact.

Unbundling
This is a term you hear in relation to customer electricity bills. Unbundling is separating the details of all the charges that go into a customer's bill, including the transmission charge, distribution charge, the charge for the commodity of electricity itself, the Debt Retirement Charge, etc. In November, 2004 the Ontario Energy Board effectively ordered re-bundling of the electricity charges. The intent was to standardize and simplify utility bills making them easier for consumers to understand.

Volt
A volt (V) is the unit used to describe the electrical energy that moves charge around a circuit.

Watt
A measure of the work electricity can do.
1000 watts = 1 kilowatt
1000 kilowatts = 1 megawatt
1000 watts = 10 100-watt light bulbs

Wholesale Market
The market in which electricity is sold to wholesalers / retailers and distributors (who, in turn, sell it to their retail customers). If a company uses a very large amount of electricity, it may wish to participate in the wholesale market directly. This will require IMO registration and OEB licensing.

Links to other sources:
http://www.energy.gov.on.ca/index.cfm?fuseaction=conservation.glossary