Southern Company and Mississippi Power announced Wednesday afternoon that they would suspend all coal gasification operations at a Kemper County plant and simply use natural gas instead. The decision comes after the Mississippi Public Service Commission (MPSC) recommended that the plant burn only natural gas, which is cheaper at the moment.

The Kemper County plant was supposed to be a cutting-edge demonstration of the power of “clean coal," and, despite running five years late and more than $4 billion over budget, Kemper was able to start testing its coal gasification operations late last year. The plant used a chemical process to break down lignite coal into synthesis gas, or “syngas,” which was then fed into a generator. The syngas burns cleaner than pulverized lignite coal does. In addition, emissions were caught by a carbon capture system and delivered to a nearby oil field to help with oil extraction. That, Southern and Mississippi Power said, would reduce the greenhouse emissions of burning lignite by up to 65 percent.

But with only 200 days of gasification operations under its belt, Kemper identified more issues with its technology, including design flaws that caused leaks and ash buildup. Last week, the MPSC indicated that it would refuse to allow Southern to raise rates to cover Kemper’s continued construction and maintenance for gasification.

Today, it seems, Southern and Mississippi are taking the MPSC's recommendation seriously.

“Southern Company and Mississippi Power today announced the company is immediately suspending start-up and operations activities involving the lignite gasification portion of the Kemper County energy facility,” the two companies announced in a press release today. “The facility will continue to operate using natural gas pending the Mississippi Public Service Commission’s decision on future operations.”

The companies also said that they “believe this is the appropriate step to manage costs given the economics of the project and the Commission’s intent to establish a settlement docket to address Kemper-related matters including the future operation of the gasifier portion of the project.”

In a statement (PDF), the MPSC said that it would “proceed with its plan to issue an order addressing the future of the Kemper County facility at its meeting on July 6, 2017.”