Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in Registration Statement No. 333-222430 on Form S-3 of our report dated February 27, 2020, relating to the financial statements and financial statement schedule of Wisconsin Public Service Corporation (the "Company"), appearing in this Annual Report on Form 10-K of the Company for the year ended December 31, 2019.

/s/ DELOITTE & TOUCHE LLP

Milwaukee, Wisconsin

February 27, 2020