SO Southern Co

By Russell Gold 

The future of a Mississippi power plant aimed at showcasing "clean coal" technology is in doubt after state regulators on Wednesday issued an ultimatum to Southern Co., warning that they would not pass on more of its ballooning costs to ratepayers.

Mississippi regulators said they wanted the Kemper power plant, which has already taken $7.5 billion and seven years to finish, to run using natural gas henceforth, and don't want to pass on additional costs to electricity customers.

The plant has primarily been running on natural gas, not coal, because the company has struggled to make the clean coal technology consistently work.

The regulators' action leaves Southern with a difficult decision over how to salvage its costly investment, including possibly having to write down part of the value of the facility.

Ending the plant's clean coal experiment would be a major setback for efforts to use technology to remove carbon emissions from coal plants, an idea the Trump administration renewed its commitment to on Tuesday.

"We are telling the parties to get a plan and get a settlement in 45 days that does not increase rates one penny," said Mississippi Public Service Commission Chairman Brandon Presley.

A spokesman for Southern subsidiary Mississippi Power didn't immediately respond to requests for comment.

Write to Russell Gold at russell.gold@wsj.com

(END) Dow Jones Newswires

June 21, 2017 16:52 ET (20:52 GMT)

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