Glossary
Alberta Electric System Operator (AESO): The AESO is the independent, not-for-profit entity responsible for the safe, reliable and economic planning and operation of the Alberta Interconnected Electric System. The AESO determines the need for transmission projects in Alberta.
Alberta Interconnected Electric System (AIES): Alberta's transmission system or grid which is planned and operated by the AESO.
Alberta Utilities Commission (AUC): The AUC is an independent, quasi-judicial agency of the Government of Alberta responsible for ensuring that the delivery of Alberta's utility services takes place in a manner that is fair, responsible and in the public interest. The AUC ensures that electric facilities are built, operated, and decommissioned in an efficient and environmentally responsible way. AltaLink and EPCOR, the Heartland Project Team, must file an application with the AUC to obtain approval to construct and operate the Heartland Transmission Project.
AUC Rule 007: A rule administered by the Alberta Utilities Commission (AUC) that specifies the information requirements and describes the application filing process for alterations to or proposals to construct new power plants, substations and transmission lines.
Breaker: A breaker is an electrical switch designed to protect a circuit. Breakers are made in varying sizes, from small devices that protect household appliances to large devices designed to protect high voltage circuits in substations.
Circuit: A circuit is a group of wires electricity flows through. Lines can be single or double circuit. A single circuit line has three wires and a double circuit line has six. A transmission line may also have one or two shield wires on the top of the structures to protect the line from lightning.
Constraints: Obstacles, either structural or geographical, in a specific area or areas which represent potentially higher impact that should be avoided by a transmission line.
Desk top study: Involves the analysis of information gathered from such sources as literature, data bases, maps and previous studies. The types of information gathered include: environmentally significant areas, landscape and geographic information, residential areas, legal limitations, municipal infrastructure and other possible challenges, obstacles and opportunities that exist in different geographic areas. This information is used to identify potential route locations with the least overall impact.
Distribution: After transmission lines bring the power from generating facilities to substations and the voltage is reduced, distribution lines carry the lower voltage electricity to your communities, homes and businesses.
Distribution system: A system of electric distribution wires that supply electricity to consumers. Distribution wires are energized at 25 kV or less.
Kilovolt (kV): Equal to one thousand volts. This unit of measurement is most commonly used when describing transmission and distribution lines. Distribution and transmission lines in Alberta carry between 4 kV (4,000 volts) and 500 kV (500,000 volts).
Facility application (FA): This is the application that the Heartland Project Team will be submitting to the Alberta Utilities Commission for approval to construct and operate the transmission line. The facility application will include information such as technical details, consultation feedback, cost, environmental studies, proposed project schedules and routing options.
Generation: Generating facilities convert various forms of energy into electric power. Most of the electricity generated in Alberta comes from coal or natural gas plants, which create electricity by burning the coal or natural gas and generating steam to turn a turbine.
High voltage transmission line: High voltage electric transmission wires that carry electricity from one point to another. The term includes all support structures and other equipment associated with the wires. For the Heartland Project double circuit 500 kV high voltage towers are proposed.
Major aspects: A set of criteria described in AUC Rule 007 which the Heartland Project Team considers in identifying and evaluating potential transmission line locations.
Public consultation: A process that allows anyone potentially affected by a particular project to become informed and to ask questions and have them answered, raise concerns and have them addressed, and provide input into the project and have their voices heard.
Quarter lines: A legal boundary which divides a one mile by one mile section of rural land into quarters. Each quarter section is 1/2 mile by 1/2 mile in size.
Right-of-way: A right-of-way is the use of a strip of land acquired for the construction and operation of a transmission line. The land is typically an easement for a specific purpose.
Route location: A proposed line that will be further examined for routing a transmission line. If approved, only one route will be selected by the AUC for construction.
Route path: The four general geographic options indicated on the map: west of Edmonton, west TUC, east TUC and east of Edmonton. In each route path are potentially hundreds of route options which will eventually lead to preferred and alternate routes.
Setback: An area that will restrict the construction or development of a transmission line. An airport is a setback.
Stakeholder: Any individual, organization, group or business that is potentially directly and adversely affected by the Heartland Transmission Project. Landowners, occupants and residents which may be affected by a potential route location.
Substation: Substations are the connection point between high-voltage transmission lines and the lower voltage distribution lines found in your community. When power passes through a substation its voltage is reduced so it can be transported to you through the distribution system.
Transformer: A transformer is the device in a substation that steps voltage up or down.
Transmission: Transmission lines connect the power produced at generating facilities to substations. Over long distances it is most effective to transport electricity at high voltages.
Transportation/Utility Corridor (TUC): In the 1970s, the Government of Alberta designated specific land around the cities of Edmonton and Calgary for future infrastructure such as ring roads, major utilities and pipelines, storm water management facilities and municipal services. For more information about the TUC, please visit the Buildings and Land section of the Alberta Infrastructure website at www.infrastructure.alberta.ca.
Vegetation Management: The use of mechanical, chemical (herbicide) and other techniques to ensure the safe and reliable operation of transmission lines. These practices are used to encourage the growth of low-growing vegetation which will reduce the risk of a power outage caused by branches or limbs contacting transmission lines. Where chemical controls are used all applications are done in accordance with the Environmental Protection and Enhancement Act.
Voltage: A unit of electric pressure.