Xcel to Build Midwest’s Biggest Battery at Sherco

• Xcel plans the Midwest’s largest 600‑MW battery at Minnesota’s Sherco site, repurposing coal-era grid to bolster reliability, enable renewables, and accelerate decarbonization—pending regulatory approval.

Xcel Energy (NASDAQ: XEL) filed plans with Minnesota regulators to build a 600‑MW battery energy storage system at the Sherco power site in central Minnesota, calling it the Midwest’s largest battery project. The facility would be sited near the coal‑fired Sherco station in Becker, repurposing existing grid infrastructure.

The proposed BESS is intended to support reliability and renewable integration as Xcel retires coal units and advances decarbonization targets. The plan requires regulatory approval; Xcel did not disclose detailed cost or schedule in the filing. If approved, the project would mark a major storage buildout in the Upper Midwest power market.

How will Xcel’s 600‑MW Sherco BESS impact Minnesota grid reliability and renewable integration?

• Adds multi-hour firming to shift surplus wind/solar to evening and morning net-peak periods, reducing curtailment and better aligning supply with demand
• Reuses the Sherco 345‑kV interconnection and switchyard, providing voltage support and stability at a major grid node while avoiding new transmission bottlenecks
  
• Supplies fast frequency response, spinning/contingency reserves, ramping support, and reactive power—services once provided by the retiring coal units
  
• Delivers accredited capacity for resource adequacy; a 600‑MW, multi-hour system can cover a significant share of net‑peak risk and reduce reliance on gas peakers during extreme conditions
  
• Enhances winter reliability with rapid start, cold‑weather capable storage that can respond during polar vortex events and sudden generator or transmission outages
  
• Lowers congestion and price volatility by absorbing power when the Upper Midwest wind fleet is oversupplying and discharging into load centers when transmission is constrained
  
• Improves renewable integration by time‑shifting midday/overnight generation, cutting curtailments, and enabling higher penetration of new wind and solar in MISO North
  
• Supports black‑start and grid‑forming capabilities at a strategic location, accelerating coal retirements without sacrificing system stability
  
• Defers some transmission upgrades by using existing infrastructure to balance local supply/demand and manage flows on key 345‑kV corridors
• Reduces emissions and fuel costs by displacing peaker operation and optimizing renewable output, with co‑location potential for future solar or hybrid configurations