Members, Tri-State execute new, more flexible wholesale electric service contracts 

• Thirty-six members representing 98% of Tri-State’s load execute new contracts, with 2066 or 2050 terms. 

• Contracts support greater flexibility, with a revised policy increasing member distributed generation self-supply opportunities to 20% from 5%. 

• Thirty-two members, representing 88% of continuing member load, execute contract terms through 2066, representing a long-term commitment to the cooperative model for power generation and delivery. 

(June 9, 2025, Westminster, Colo.)  In a strong signal of support for the cooperative business model and distribution utilities working together to secure a reliable and affordable power supply, the great majority of continuing utility members have executed new wholesale electric service contracts with not-for-profit wholesale power supply cooperative Tri-State Generation and Transmission Association. 

Thirty-two Tri-State utility members, representing approximately 88% of Tri-State’s continuing member load, signed new contracts through 2066. The contracts support long-term affordability as Tri-State pursues the largest addition of new resources in its history, allowing Tri-State to optimize financing of its planned projects and to solidify its long-term planning to the benefit of its membership. Additionally, four Tri-State utility members, representing 10% of Tri-State’s continuing member load, signed new contracts with a 2050 term.  

The new contracts support greater flexibility for Tri-State members, including through a complementary policy filed with the Federal Energy Regulatory Commission that will increase member distributed generation self-supply provisions to 20% from 5%. This flexibility is in addition to Tri-State’s innovative Bring Your Own Resource program, which provides members with the opportunity to supply up to 40% of their requirements. 

“Continued membership in Tri-State delivers a growing, increasingly diverse generation portfolio, ownership of the largest cooperative transmission network in America, greater self-supply flexibility and valued energy services, all within the not-for-profit cooperative business model,” said Tri-State Chief Executive Officer Duane Highley. “Together, we will serve rural communities with reliable and affordable power for years to come.” 

“The contract extension supports Mountain View Electric‘s long-term reliability and affordability goals, and strengthens our ability to plan, invest in infrastructure and navigate a changing energy landscape, while staying true to our cooperative values,” said Ruth Marks, chief executive officer of Mountain View Electric Association (Limon, Colo.).

Tri-State membership gives our small rural Wyoming co-op the advantages of a much larger utility, so that we will always have the power supply we need at a price our members can afford,” said Molly Lynn, general manager of Garland Light and Power Co. (Powell, Wyo.).  

“Extending our contract with Tri-State ensures we can continue to work with our fellow not-for-profit distribution utilities and puts Midwest Electric in the best position for our future power supply needs,” said Jayson Bishop, general manager of Midwest Electric Cooperative Corporation (Grant, Neb.).  

“True to our cooperative model, updating our contract was a collaborative process between the Tri-State members, ensuring the contract language and term works well for the needs of individual members and supports the goals we set for Tri-State,” said Guy Payne, general manager, Sierra Electric Cooperative (Elephant Butte, N.M.). 

The new contracts were developed over more than a year through a Contract Committee of the Tri-State membership. The Tri-State Board of Directors, representing the utility members, accepted the committee’s recommendations. The signed contracts will be filed with the Federal Energy Regulatory Commission. 

“The member-led work of our Contract Committee delivered a new contract that will help Tri-State continue to serve our rural communities with a resilient, flexible and affordable power supply,” said Tri-State Chairman Tim Rabon, who serves as Trustee of Otero County Electric Cooperative (Cloudcroft, N.M.). 

Two Tri-State members, representing 2% of continuing member load, elected to maintain their current contracts with a 2050 term. Two other members previously provided two-year unconditional contract termination notices and are not continuing with Tri-State membership after their expected respective withdrawals in 2026 and 2027.  

About Tri-State   

Tri-State is a power supply cooperative, operating on a not-for-profit basis, serving electric distribution cooperatives and public power district member-owners in four states. Together with our members, we deliver reliable, affordable and responsible power to more than a million electricity consumers across nearly 200,000 square miles of the rural West. Visit www.tristate.coop. 

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Contact:   

Lee Boughey, VP Strategic Communications, 720-670-6696, lee.boughey@tristategt.org   

Mark Stutz, 303-254-3183, mark.stutz@tristategt.org   

Certain information contained in this press statement are forward-looking statements including statements concerning Tri-State’s plans, future events, and other information that is not historical information. These forward-looking statements are subject to a number of risks, uncertainties and assumptions, including those described from time to time in Tri-State’s filings with the Securities and Exchange Commission. Tri-State’s expectations and beliefs are expressed in good faith, and Tri-State believes there is a reasonable basis for them. However, Tri-State cannot assure you that management’s expectations and beliefs will be achieved. There are a number of risks, uncertainties and other important factors that could cause actual results to differ materially from the forward-looking statements contained herein.