WiLLMAR — Investing in transmission has been a major focus of Willmar Municipal Utilities for the past several years, and that was made clear during a recent tour for the Municipal Utilities Commission on Aug. 8.
“At the utility, whenever we get a chance to invest in transmission, we like to invest into transmission,” Harren said, noting that there is a guaranteed 10-11% return on investment for transmission. “We made a number of investments over the years that provide additional reliability, additional capacity to Willmar, in addition to the return on investment that you are guaranteed through the (public utility commission’s) approval.”
Electric transmission infrastructure is regulated in order to prevent utilities from overbuilding infrastructure that is not needed, according to Willmar Municipal Utilities electrical engineer Jeron Smith.
Willmar Municipal Utilities is a member of Missouri River Energy Services, which generally conducts the transmission planning studies needed to gain permission from the Midcontinent Independent System Operator to build additional transmission facilities.
Willmar Municipal Utilities also partners with Great River Energy, because it owns a significant amount of transmission in the southwest portion of Minnesota, Smith noted. WMU has been doing transmission planning studies related to the closure in 2018 of a bioenergy plant in Benson owned by Xcel Energy, according to Smith.
Smith explained that the closing of the plant created a “cavity” in this area, which led to the construction of the Priam substation and upgrades to the Willmar substation.
ADVERTISEMENT
The construction of the Priam substation in 2018 was a $5 million to $6 million investment, and the current expansion of the Priam substation is a $1.2 million investment. The expansion taking place at the Willmar substation is an $8.3 million investment, according to Smith.
One setback of the Willmar substation project is that a couple of key electrical components needed for the new control building are not yet delivered due to supply chain issues. This is slowing down the testing process needed to get the substation addition up and running, according to Smith.
The next major investment in transmission is expected to be $2 million to $4 million in 2027 if the transmission planning study can be completed by then and MISO supports the upgrade, according to Harren.
Willmar Municipal Utilities will either replace the older Toshiba transformer at the Willmar substation or add a second transformer at the Priam substation, according to Smith.
Expansion at the Priam substation included installing three additional breakers and equipment to facilitate a new transmission line that will connect to and help energize a portion of the Willmar substation, Smith said. He noted an advantage of the Priam substation is its proximity to transmission lines, which cost $1 million per mile to build.
Willmar Municipal Utilities is constructing a new substation next to the downtown Willmar Power Plant, which will be demolished once the substation is energized, according to Smith. It is hoped the $5.3 million substation will be in service in November.
However, this being the most recent substation project, it is being most affected by supply chain issues, Smith said. The control building for the substation has already been delayed more than a month, but Willmar Municipal Utilities has been informed that it will arrive in November.
If the project is not complete and the power plant substation cannot be energized by November, it will delay the demolition of the power plant, Smith noted.
ADVERTISEMENT
The demolition of the power plant is currently out to bid, and the deadline has been extended to allow contractors additional time to submit bids, according to facilities and maintenance supervisor Kevin Marti.
“It is an incredibly tight site. It will be really interesting to see how they are going to take the plant down and clean it up. It’s like trying to put a size 10 foot in an 8 shoe. It’s challenging,” Marti said.
He noted that scrap metal prices are currently elevated, which should help lower the cost of the demolition of the plant. However, there is a lot of concrete and other materials that need to be removed from the plant.