Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Registration Statement No. 333-256501 on Form S-3 of our report dated February 28, 2022, relating to the financial statements of Stem, Inc., appearing in the Annual Report on Form 10-K of Stem, Inc. for the year ended December 31, 2021. We also consent to the reference to us under the heading “Experts” in such Registration Statement.

/s/ Deloitte & Touche LLP

San Francisco, California

June 2, 2022