Huge: Underground Transmission Line gets Key Approval
Transmission in the US has stalled in part due to the onerous process of permitting across numerous small jurisdictions, and in the face of NIMBY opposition that can be empowered by that permitting process. Many of the objections are simply “I don’t want to look at it”. One proposed solution has been to place lines underground, and route them along highways or railways which have already been by definition, permitted. One such key project in the Midwest is the SOO line, designed to bring wind and solar energy from the Iowa region to distribution points near Chicago. It’s designed to follow a rail line, which in theory could make permitting easier – but it’s been held up for a couple years in a frustrating permitting process. Now a key hurdle has been cleared. If the technology can be shown to be workable and economically viable, a huge obstacle to a revamped national grid will have been overcome.
The proposed SOO Green transmission line between the Midcontinent Independent System Operator and PJM Interconnection regions cleared a key hurdle when it was approved by Iowa regulators last week.
The Iowa Utilities Board on Sept. 13 approved a petition by SOO Green HVDC Link ProjectCo, the project developer, for a franchise to build and operate the Iowa portion of the line. The 525-kV high voltage direct current line would run about 350 miles underground next to a railroad between Mason City, Iowa, and Yorkville, Illinois.
SOO Green expects its project will deliver wind generation from Iowa to the PJM market while improving grid reliability by adding 2,100 MW of transmission capacity between MISO and PJM, according to the IUB’s decision.
“The electric transmission line is necessary to provide adequate electric utility service and is assistive to Iowa electric customers by supporting reliability and regional transmission organization cross-seam transmission,” the IUB said. “Reliability is increased by improved ability to both send and, more importantly, receive power if MISO is experiencing generation shortfalls.”
The SOO Green project proposes to build about 175 miles of underground high voltage direct current (HVDC) transmission line in Iowa, delivering wind, solar and possibly other energy from a converter station east of Mason City to the Iowa-Illinois border, then continuing to the Plano, Illinois, area.
The total transmission line would be about 349 miles long, although the company has identified possible expansions into northwestern Iowa, Minnesota and Missouri if market conditions justify it.
The franchise permit requires that the line operates as a merchant line, meaning the costs of the project will be paid by financial investors, who will earn a return on their investment through fees charged to transport energy. No public utilities will seek rate increases to pay for any part of it, the company said.
The 525-kilovolt line would cross through Cerro Gordo, Floyd, Chickasaw, Winneshiek, Allamakee, Clayton, Dubuque and Jackson counties in Iowa.
The primary route would run along Canadian Pacific Railroad right-of-way from Mason City through Charles City, through New Hampton over to Marquette, down along the Iowa side of the Mississippi River to Sabula, under the Mississippi River and then to Byron, Illinois, finally ending in Plano, Illinois.
Almost all of the project in Iowa will be located on private railroad rights-of-way owned by Canadian Pacific Kansas City Limited (Canadian Pacific Railroad) and on 18 miles of public road rights-of-way along Highway 18 in Clayton County.
The Iowa Utilities Board (IUB) did grant SOO Green HVDC Link ProjectCo the right to use eminent domain to force access to four parcels of property in Clayton County and two parcels in Dubuque County along the railroad right of way.
“Today’s order finds that the proposed line is necessary to serve a public use and represents a reasonable relationship to an overall plan of transmitting electricity in the public interest,” the IUB said in a statement released Wednesday.
“The order also found that vesting SOO Green with the right of eminent domain is necessary for public use,” it said.
“By burying the transmission cables on property already owned or controlled by railroads, instead of stringing them on high-rise towers, the project would limit environmental impact and hopes to avoid landowner and neighbor resistance that has thwarted some other high voltage overhead power transmission projects,” the company said when the project was announced in January 2020.
Soo Green Graphics
The line would also be more secure from weather-related power disruptions such as those caused by ice storms or high winds, the company said. In addition to delivering power to the east, electricity could flow the other way if it was needed because of emergencies with Midwest power supplies including in Iowa.
