ITC Midwest: Minnesota-Iowa 345-kV line’s cost estimate peaks at $370m

ITC Midwest has estimated the Minnesota to Iowa 345-kV (MN to IA) project to cost between $271m to $283m, plus or minus 30%, depending on the final route, according to its certificate of need application filed with the Minnesota PUC on March 22.

According to the cost estimate range, the potential 30% variation would yield a minimum project cost of $189m and a maximum project cost of $368m.

The project is proposed to improve reliability and capacity, and to increase generation interconnections, a spokesperson told TransmissionHub on March 28. The company expects the Minnesota PUC to issue the certificate of need and a route permit in the spring of 2014.

“In Minnesota, the process is we file [our application], it goes through regulatory review and a route decision and then we start talking to landowners once the route is defined,” the spokesperson said. “In Iowa, we have public information meetings, and then talk to landowners to get a final route” before making a certificate of need filing.

ITC Midwest will hold its first Iowa public information meeting in April.

The MN to IA project is a 100-mile, 345-kV transmission line that will include the construction of 75 miles of new transmission lines in Minnesota, 25 miles of new lines in Iowa and new and expanded substations. The project is scheduled to begin construction in 1Q16 and to enter service in mid-2017.  

ITC Midwest proposes to expand its existing Lakefield Junction substation for a new 345-kV line to be constructed between the substation and a new Huntley substation, proposed to be located south of the existing Winnebago Junction substation; remove the Winnebago Junction substation; and reconnect to Huntley the four existing 161-kV lines that currently connect to Winnebago Junction. From Huntley, the 345-kV transmission line will run south to cross the Minnesota/Iowa border and connect first to a new ITC Midwest Ledyard substation, and then to MidAmerican’s new Kossuth County substation, both in Kossuth County, Iowa.

The first segment of the Minnesota portion of the project, between Lakefield Junction and Huntley, is expected to be complete in early 2017, and the second segment, between Huntley to the Iowa border, is expected to be complete by mid-2017.

The Minnesota portion of the project is estimated to cost between $194m and $206m, plus or minus 30%, depending on the route chosen, while the Iowa portion of the project is estimated to cost about $77m, plus or minus 30%, according to the CPCN application.

For the Minnesota portion of the project, ITC Midwest has proposed two options: Route A, which is ITC Midwest’s preferred route and is estimated to cost $206m, and Route B, which is estimated to cost $194m.

Route A would primarily follow an existing ITC Midwest 161-kV transmission line through the Lakefield Junction, Fox Lake, Rutland, Winnebago Junction substations to Faribault substation. From the Faribault substation, the 161-kV line continues to the Iowa border and terminates at the Winnco substation in Kossuth County, Iowa.

Route B would run on new right-of-way (ROW) along existing road ROW and agricultural field lines from the Lakefield Junction substation to the Huntley substation to the Iowa border. Route B is separated from Route A by about two miles. Route B’s structures would also be 345/161-kV double-circuit-capable to accommodate future expansion, but ITC Midwest would initially only install arms for the 345-kV line.

MN to IA as part of MVP Project 3

The MN-IA project comprises a portion of Project 3 in the Midwest ISO’s (MISO) multi-value project (MVP) portfolio. As proposed, it will run from the ITC Midwest’s existing Lakefield Junction substation in Jackson County, through Martin and Faribault Counties in Minnesota, and terminate at a new Kossuth County substation owned by MidAmerican in Kossuth County, Iowa.

From its Kossuth County substation, MidAmerican proposes to build two 345-kV lines: one running south to its existing Webster substation near Fort Dodge, Iowa, and the other running west to its new O’Brien County substation near Sanborn, Iowa.

Together, the ITC Midwest and MidAmerican facilities comprise MVP Project 3.

MVP Project 3 yields three major benefits, according to the filing: it will increase generation transfers, specifically wind generation, throughout the MISO footprint, including in Minnesota; improve system reliability by relieving heavy loading on southern Minnesota’s system; and result in lower cost energy to Minnesota consumers. According to a model ITC Midwest ran on locational marginal prices (LMPs), Project 3 will reduce LMP payments of between $48.3m and $76.6m.

Project details

The MN to IA project would primarily use single pole, weathering or galvanized steel double-circuit 345-kV/161-kV structures on a 200-foot ROW. The single pole structures would be placed at spans ranging between approximately 600 to 1,000 feet, with an average span of approximately 900 feet, according to the application.

Where the 345-kV line is double-circuited with the 161-kV line or other transmission facilities (Route A), ITC Midwest would use double-circuit structures with six conductors installed. If the Minnesota PUC selects a route other than the one primarily following the existing 161-kV line, ITC Midwest would construct double-circuit 345-kV/161-kV-capable facilities, but with only the 345-kV arms and conductors installed. The other side would be fitted with 161-kV arms, insulators, and conductor when future conditions warrant addition of a 161-kV line, ITC Midwest said.

Each phase will consist of two twisted pair Drake (2-795) Aluminum Conductor Steel Reinforced (ACSR) cables, or cables of comparable capacity in a bundled configuration, ITC Midwest said.

“The design of two twisted pair conductors in a bundled configuration reduces ice buildup on the conductor, therefore reducing galloping during windy and icy conditions,” the company said.

Each conductor is approximately 1.8 inches in diameter (795 kcmil). Each ACSR cable consists of a core of seven steel conductors surrounded by 26 aluminum strands. ITC Midwest proposes to use the same conductor and bundled configuration for all the 345 kV sections of the transmission line in Minnesota and in Iowa. The 345-kV twisted pair conductors (two sets of three conductors) will have a capacity equivalent to 3,000 amps, the company said.

ITC Midwest is a subsidiary of ITC Holdings (NYSE:ITC). 

About Rosy Lum 525 Articles
Rosy Lum, Analyst for TransmissionHub, has been covering the U.S. energy industry since 2007. She began her career in energy journalism at SNL Financial, for which she established a New York news desk. She covered topics ranging from energy finance and renewable policies and incentives, to master limited partnerships and ETFs. Thereafter, she honed her energy and utility focus at the Financial Times' dealReporter, where she covered and broke oil and gas and utility mergers and acquisitions.