The Alberta Utilities Commission (AUC) on Oct. 7 approved a total of eight applications connected with two projects that will expand and enhance the transmission system in the vicinities of southeast Calgary, Okotoks and High River, Alberta.
The applications included a needs identification document for the Foothills Area Transmission Development project and an amendment of the needs identification document for the Southern Alberta Transmission Reinforcement project by the Alberta Electric System Operator (AESO), five facility applications filed by AltaLink Management, and an application by ENMAX Power Corporation to alter and operate one of its existing substations to meet the remainder of the need described in the AESO’s needs identification documents.
The facilities proposed by AltaLink include approximately 124 miles of contiguous transmission lines connecting southeast Calgary to the High River area and to the Fort Macleod area, and approximately 11 miles of transmission line connecting southeast Calgary eastward to the Langdon area. The lines would operate at 240-kV and 138-kV.
The Foothill Area project consists of four segments. The Langdon to Janet project, connecting the southeast part of Calgary to the Langdon, Alta., area, includes 11 miles of double-circuit, 240-kV transmission in AltaLink’s service area between the Langdon 102S substation to Janet 74S substation, and four miles of line in ENMAX’s service area.
The second segment, the North Foothills project, is a double-circuit, 240-kV line that would connect the Foothills 237S substation to the ENMAX No. 65 substation in southeast Calgary. Also 11 miles in length, the AUC favored the alternate route, which has less environmental impact and is $9.5m less expensive due to steel monopoles that would be required for the preferred route. However, the AUC cannot issue a permit and license for the construction and operation of the north Foothills application within the Calgary transportation and utility corridor without the prior written consent of the Minister of Infrastructure, which AtlaLink has said it will pursue.
The third segment is the Foothills 138-kV project, which would extend approximately eight miles from the Foothills 237S substation to the High River 65S substation.
A fourth project involves the addition of two 240-kV circuit breakers and other reconfiguration and alterations at ENMAX’s existing No. 65 substation.
The Southern Area transmission reinforcement project includes the south Foothills transmission development project, which consists of seven discrete segments, including construction of approximately 75 miles of double-circuit 240-kV line from the new Windy Flats 138S substation to the Foothills 237S substation, and associated line and substations modifications.
The remaining projects involve reconfiguration and alterations at AltaLink’s Windy Flats substation.
The AUC noted that no party disputed the AESO’s conclusion that there is a need to expand and enhance the transmission systems. “To the contrary, all of the parties recognized that some measures were required to address this need. The real dispute amongst the parties relates to the means proposed by the AESO to address the identified need,” the AUC wrote.
The total estimated cost for all the approved projects is approximately C$827m, the AUC said in its order approving the eight applications.
Two approvals from the AUC are required to build new transmission in Alberta, unless that transmission has been declared critical transmission infrastructure.
Under the province’s Electric Utilities Act, the AESO is responsible for preparing the needs identification document, which describes the need for new transmission and proposes a transmission solution to meet that need. The AESO then files a need application with the AUC for approval. Facility applications are prepared by a transmission facility owner assigned by the AESO and filed with the AUC. The AUC may approve, approve with conditions, or deny such applications.
In its needs identification documents, the AESO said that transmission system constraints could occur as early as 2014.