BHE Rate Increase Legal Notice — April 2, 2026

PUBLIC NOTICE

Pursuant to the Wyoming Administrative Procedure Act and the Wyoming Public Service Commission’s (Commission) Rules and Regulations, notice is hereby given of the Application of Black Hills Power, Inc. d/b/a Black Hills Energy (BHP or the Company) requesting authority to increase its retail electric service rates by approximately $5,121,592 million per year, or an average overall increase of 29% with rates effective on and after May 1, 2026; revise the Energy Cost Adjustment  Mechanism (ECAM); establish an Insurance Deferred Accounting regulatory asset and a Decommissioning Cost Deferred Accounting regulatory asset; establish a new Spare Turbine Adjustment Rider (STAR); consolidate lighting classes; and increase the Major Maintenance Regulatory Liability for generating units, as more fully described below:

1. BHP is a wholly owned subsidiary of Black Hills Corporation that provides electric utility service to the towns of Newcastle, Upton, Osage, and Colony, Wyoming. BHP is public utility subject to the Commission’s jurisdiction. Wyo. Stat. §§37- 1-101(a)(vi)(C) and 37-2-112.

2. On March 18, 2026, BHP submitted the Application, together with supporting testimony, exhibits and revised tariff sheets, requesting the Commission approve the Company’s proposal to implement an increase in its Wyoming retail electric utility service rates of $5,121,592 per annum, or an average overall increase of 29%. The Company requests an effective service date of May 1, 2026. 

3. BHP requests a return on common equity of 10.5% and a cost of debt of 5.46% resulting in an overall cost of capital and return on rate base of 8.13%. The Company states this reflects market circumstances for the twelve months ending September 30, 2026. BHP states the requested rate increase is primarily driven by the Company’s need for a fair return on the necessary capital invested to continue providing safe and reliable service, as current rates do not reflect the cost of providing electric service to its customers.

4. BHP’s proposed percentage increase in price changes by rate schedule are:

The Company states that due to rate design and individual customer load factors and usage characteristics, the percentage rate change to individual customers within each rate schedule may be higher or lower than the average for the customer class or rate schedule.

5. The Company also proposes revising the ECAM by changing how Long-Term Wholesale Revenue credit is calculated; eliminating the minimum $1.5 million Power Marketing Credit; including all revenue associated with the Balancing Authority Federal Energy Regulatory Commission tariffs as a credit to the ECAM; changing the annual calculation period; and changing Application filing date.

6. BHP requests the Commission approve its request for deferred accounting treatment of the Ben French generating units and deferred accounting treatment of insurance costs to track and recover unanticipated costs associated with decommissioning the Ben French facilities and payment of variable insurance expenses and premiums. BHP also proposes increasing the Major Maintenance Regulatory Liability to account for general increased maintenance costs, to include additional generating unit costs, and to prevent disproportionate cost allocation.

7. BHP requests Commission approval to implement the STAR to record all revenue and expenses related to the Company’s Spare Turbines and usage charges. BHP also proposes revising all current BHP owned Street Lighting rates and Private Area Lighting rates to include LED standards and fixtures and removing the Mercury Vapor rates. 

8. This is not a complete description of BHP’s Application. You may review the Application and its supporting testimony and exhibits at BHP’s Wyoming offices or online at: http://www.blackhillsenergy.com/reliable-wy and at the Commission’s office or online at: https://dms.wyo.gov/external/publicusers.aspx (enter Record No. 18089).

9. Anyone desiring to file a statement, intervention petition, protest or request for a public hearing in this matter must do so, in writing, on or before April 24, 2026. Petitions shall set forth the grounds of the proposed intervention or request for hearing as well as the position and the interest of the petitioner in this proceeding. The Commission encourages the public’s participation and comments will be received throughout the entirety of this proceeding. The opportunity to present verbal comments will be available to anyone appearing, either in person or remotely, during future public proceedings related to this matter. Submitting written comments to the Commission by the deadline set forth above may allow for resolution of issues and/or concerns identified therein. Please mention Docket No. 20002-148-ER-26 in all correspondence with the Commission.

10. If you wish to participate in this matter and you require reasonable accommodation for a disability, please contact the Commission at (307) 777-7427, or write to the Commission at 2515 Warren Avenue, Suite 300, Cheyenne, Wyoming 82002, to make necessary arrangements. Communications impaired persons may also contact the Commission by accessing Wyoming Relay at 711.

Dated: March 24, 2026.