Environmental Assis for Orono Substation Expansion

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3.9 Associated Facilities and Substations The project would include replace the existing 69 kV Orono Substation with an expanded 115 kV substation at the same location. The Project would also modify Xcel Energy's existing transmission line 0831 by replacing a 1,030 -foot single -circuit section with a new 1,020- foot single -circuit section. The Project would install a 2,160 -foot segment of new double circuit 115 kV/115 kV transmission line between the Orono Substation and transmission line 0831. The replacement substation will not have 69 kV transmission equipment; as a result GRE's existing 69 kV Line BD will be re-routed around the replacement substation (Xcel Energy, June 7, 2011). 3.10 Cost As provided in the route permit application, transmission line costs would vary depending on the structure type, the height and diameter and composition of the structures, the number of structures per mile, labor and hardware costs. The line construction costs include the cost of structures, insulators, conductors, and labor as well as any costs of equipment that will be used to construct the new line, but do not include right-of-way acquisition costs. Construction costs also include modifications to the Orono Substation. The estimated project costs are summarized in Table 3. Table 3: Estimated Project Costs Source: Xcel Energy, June 7, 2011; Xcel Energy, personal communication, October 13, 2011. Xcel Energy indicates that operating and maintenance costs for the transmission line will be nominal for several years, since the transmission line will be new and would require minimal vegetation maintenance. Xcel Energy's typical annual operating and maintenance costs, for 115 kV transmission lines in its Upper Midwest system, incorporating line and inspections, vegetation management, and maintenance and repairs as needed, are approximately $300 to $500 per mile of transmission line right-of-way. Transmission line inspections are typically performed by airplane or helicopter on a regular basis. Inspections of substations and other equipment are generally performed on an annual or semi-annual basis depending on the type of equipment. Maintenance and repairs to substations are performed on an as -needed basis with costs varying from substation to substation (Xcel Energy, 2011 a). Environmental Assessment PUC Docket E002/TL-11-223 Page 13 Baker Park Reserve Route Proposed Route Alternative New Transmission Line $1.2 million $1.3 million Orono Substation Removal and Replacement $4.1 million $4.1 million Total Project Cost $5.3 million $5.4 million Source: Xcel Energy, June 7, 2011; Xcel Energy, personal communication, October 13, 2011. Xcel Energy indicates that operating and maintenance costs for the transmission line will be nominal for several years, since the transmission line will be new and would require minimal vegetation maintenance. Xcel Energy's typical annual operating and maintenance costs, for 115 kV transmission lines in its Upper Midwest system, incorporating line and inspections, vegetation management, and maintenance and repairs as needed, are approximately $300 to $500 per mile of transmission line right-of-way. Transmission line inspections are typically performed by airplane or helicopter on a regular basis. Inspections of substations and other equipment are generally performed on an annual or semi-annual basis depending on the type of equipment. Maintenance and repairs to substations are performed on an as -needed basis with costs varying from substation to substation (Xcel Energy, 2011 a). Environmental Assessment PUC Docket E002/TL-11-223 Page 13