PUC Clears Major Southern Minnesota Transmission Buildout, Rewiring the Upper Midwest Grid

ST. PAUL, MN

In a decision that will reshape the electrical backbone of southern Minnesota for generations, the Minnesota Public Utilities Commission on February 5, 2026, formally approved Xcel Energy’s Mankato–Mississippi River Transmission Project, a sweeping high voltage infrastructure initiative aimed at relieving grid congestion, strengthening reliability, and accelerating the region’s transition to renewable power.

Known as the Mankato–Mississippi River Transmission (MMRT) Project, the buildout is led by Xcel Energy in partnership with Dairyland Power Cooperative, Rochester Public Utilities, and the Southern Minnesota Municipal Power Agency. State regulators approved both the project’s Certificate of Need and its route permit, clearing the final major regulatory hurdles after more than two years of study, public hearings, and environmental review.

At its core, the project is a keystone investment within the Midcontinent Independent System Operator Long-Range Transmission Plan, a multi-state effort to modernize an aging Midwestern grid built for a different energy era.

A new backbone for a changing grid

The MMRT project consists of two major high voltage segments designed to move large volumes of electricity across southern Minnesota and into Wisconsin:

• A 345 kilovolt transmission line, roughly 120 to 130 miles in length, connecting Xcel’s Wilmarth Substation in Mankato to a connection point near Kellogg along the Mississippi River.
• A 161 kilovolt transmission line, approximately 20 miles long, linking the North Rochester Substation near Pine Island to an existing line northeast of Rochester.

According to state filings, the approved route crosses portions of Blue Earth, Le Sueur, Rice, Waseca, Dodge, Goodhue, Olmsted, and Wabasha counties. Regulators noted that nearly 80 percent of the alignment follows existing transmission corridors, including the CapX2020 corridor, as well as section lines and field boundaries, an approach intended to limit new land disturbance.

Why regulators said yes

In approving the project, commissioners cited a convergence of reliability, economic, and energy transition needs.

Southern Minnesota and the Upper Midwest have become major producers of wind energy, but the region’s existing transmission system has struggled to carry that power to population centers. During periods of high wind and constrained transmission capacity, grid operators are often forced to curtail low cost renewable generation, shutting it down even when demand exists elsewhere on the system.

The MMRT line is designed to act as a new electrical highway, easing congestion on the 345 kV system in southern Minnesota and western Wisconsin and allowing more renewable energy to flow east and south through the MISO market.

Xcel Energy estimates the project will deliver up to $3.8 billion in systemwide economic savings over 40 years, driven by lower congestion costs, improved market efficiency, and greater access to low cost wind and solar resources. Company filings emphasize that these benefits accrue across the broader MISO footprint, not as a direct, immediate credit on individual utility bills, but as long-term downward pressure on regional energy costs.

Commissioners also highlighted reliability concerns. By adding new network connections and redundancy, the MMRT project strengthens the backbone of the regional grid, reducing the risk of outages during extreme weather events and improving system resilience as older coal fired plants continue to retire.

Tied to clean energy goals

The transmission approval carries broader implications for Minnesota’s clean energy transition.

Xcel Energy has committed to reducing carbon emissions from its Upper Midwest operations by 85 percent by 2030 and delivering 100 percent carbon free electricity by 2050. Regulators and grid planners alike have stressed that achieving those targets is not possible without significant transmission expansion.

Large scale wind and solar resources are often located far from cities and industrial load centers. Without new transmission, those resources remain stranded. The MMRT project is explicitly designed to unlock that generation and integrate it reliably into the regional grid.

A long road from planning to steel in the ground

The PUC’s vote follows years of public engagement. Xcel Energy reports holding dozens of open houses, meeting with hundreds of landowners, and receiving extensive written and oral testimony during contested case proceedings.

With approvals now in hand, the project moves into its execution phase:

• 2026: Final engineering design, detailed permitting, and the start of right of way acquisition, including negotiations with landowners and farmers for easements and compensation.
• 2027 to 2028: Full scale construction across southern Minnesota.
• 2028 to 2029: Commissioning and placement of the lines into service.

Xcel has pledged continued outreach with local governments and affected property owners, including discussions around construction impacts, agricultural considerations, lease payments, and local job creation tied to the buildout.

A generational investment

Transmission projects rarely draw headlines, but their effects ripple for decades. Once built, the MMRT line will quietly shape how power moves across the Upper Midwest, determining which resources get used, which get stranded, and how resilient the grid remains in the face of climate driven extremes.

For regulators, the approval reflects a judgment that the cost and disruption of building new infrastructure are outweighed by the long-term risks of doing nothing. For Minnesota, it marks another step in a slow but consequential rewiring of the state’s energy future.

MinneapoliMedia