Last year, Kit Carson Electric Cooperative Inc. hit a long-awaited milestone: It met 100 percent of its daytime energy demand with solar power.

The New Mexico utility’s achievement was the result of years of new solar construction and power purchase agreements — steps that the small, rural cooperative was only able to take after making a radical change to its management structure.

In 2016, Kit Carson left the Tri-State Generation and Transmission Association Inc…

Since then, four more of Tri-State’s original 44 utility members either have left or plan to leave.

The turbulence at Tri-State may be isolated to the West, but it foreshadows a national quandary. Each of the nation’s 900 or so co-ops faces a rapid energy transition that could upend traditional business models.

“We’re seeing some really ambitious co-ops start pushing their decarbonization goals further,” said Sam Mardell, senior associate on RMI’s carbon-free electricity team. “That’s making these organizations really rethink the way they provide energy.”