United Power made it official Dec. 14. 

It filed a notice of intent to pull out of the Tri-State Generation and Transmission Association, effective Jan. 1, 2024. A press statement said the Federal Energy Regulatory Commission accepted the time frame in late October. 

"United Power has unsuccessfully attempted to modify its all requirements with the G&T (Generation and Transmission Association) for more than three years," United Power's statement said. "In the last nine months alone, United Power has tendered three formal term sheets and held numerous high-level meetings." 

But, the press release said, "leadership at the G&T has been unresponsive" to the change requests. 

“United Power’s notice to withdraw from membership is not surprising, given its actions over several years and its multiple attempts to terminate its wholesale power contract at the lowest possible cost, no matter the impact to its fellow members,” said Tri-State CEO Duane Highley in a statement. “”We worked with United Power to understand its individual needs, but each of its proposals would have harmed the other utility members of Tri-State.” 

United Power CEO Mark Gabriel said Tr-State ignored efforts “to come to an amicable arrangement that better supports the needs of our members while guaranteeing that our prior commitments are met.” 

“Instead of working with us in the pursuit of lower-cost, cleaner options, Tri-State has resisted these development," he said in a statement. 

“Contrary to United Power’s public assertions, Tri-State has moved rapidly to transition to clean energy and provide more value to its members,” Highley said in his statement. “Through its member-developed responsible energy plan, Tri-State is leading in the clean energy transition, including greatly adding significant renewable resources, decreasing carbon dioxide emissions and increasing member power supply flexibility.” 

Several cases in front of FERC and various courts (Denver, Adams County and the U.S. Court of Appeals) will decide United Power's exit fee, plus exit fees for other power coops that left Tri-State the past five years. United Power’s statement said at least six other coops are considering similar measures.