Judith Kohler, The Denver Post via TNS-AP

Tri-State Generation and Transmission, which provides wholesale power to rural electric associations across Colorado, has officially closed one of its coal power plants ahead of schedule.

Westminster-based Tri-State said the Nucla Station in far western Colorado ran through its last supply of on-site fuel Sept. 9 and was officially retired Thursday. The 100-megawatt facility was originally scheduled to shut down at the end of 2022.

Tri-State said in a statement that the closure allows it to meet its deadline for ending operations under Colorado’s plan to cut regional haze.

“While our generating station has been a significant part of Nucla and Naturita communities for many years, it made the most sense to come offline at this time in a controlled fashion, while maintaining compliance with all of our federal and state environmental regulations,” said Duane Highley, Tri-State CEO.

The utility said it will provide $500,000 over the next five years to the community to help with the transition. The 35 employees will stay to help start decommissioning the plant. Dismantling of the facility, which started operating in 1959, is expected to begin during the first half of 2020.

Tri-State spokesman Mark Stutz said in an email Friday that it hasn’t been decided yet how the $500,000 will be distributed. Employees will stay on the job through the spring of 2020. Stutz said the majority of the workers were planning to retire or move other jobs with Tri-State.

“Tri-State has education programs being offered and other assistance for employees, during the transition,” Stutz said.

Tri-State first announced the early retirement of the plant in July, along with the announcement of its “Responsible Energy Plan.” The company said the plan is intended to meet new carbon reduction and renewable energy goals and requirements for resource planning.

Legislation passed this year by Colorado lawmakers requires Tri-State to submit its plans to the Colorado Public Utilities Commission for approval. New Colorado laws also set statewide goals for cutting climate-changing greenhouse gases.

Tri-State has been criticized by some of its member cooperatives and renewable energy advocates for relying too heavily on coal and for capping the amount of electricity members can generate on their own. However, Tri-State officials have said the power provider gets about a third of its electricity from renewable energy sources, plans to add more and will work with members to give them more flexibility to produce more of their own electricity.

While saying it will comply with Colorado’s planning requirements and carbon-emission reduction goals, the Tri-State board voted in July to have the Federal Energy Regulatory Commission regulate its rates. The utility, which has a total of 43 member cooperatives in Colorado, Wyoming, Nebraska and New Mexico, has said having FERC regulate its rates would give it more flexibility than being subject to regulation by four different states.

In early September, Tri-State added MIECO Inc., a wholesale energy services company, as a member. To qualify for federal regulation, a power provider has to include members that are not small electric cooperatives or a government entity.

Colorado regulators have questioned Tri-State’s move to federal oversight.