Kemper IGCC In-Service Date Pushed to Q3, Costs Surge Again

Mississippi Power’s lignite-fired Kemper County integrated gasification combined cycle (IGCC) power plant is seeing yet another delay and $110 million in new costs, a filing with state regulators shows.

The company’s December 2015 monthly status report for the nation’s first commercial power plant that will capture and store carbon dioxide anticipates that it will now come online during the third quarter 2016, likely by August 31.

In October 2014, the in-service date of the plant whose construction was begun in 2010 was postponed to the first half of 2016. The latest delay means the project is now more than two years behind schedule.

New Cost Increases

In the filing submitted to the Mississippi Public Service Commission (MPSC) on February 2, the company also reported it had revised cost estimates based on the delays. The total estimated cost subject to the MPSC-set cost cap of $2.88 billion as of December 31 was about $5.294 billion, net of federal grants. Total project costs amount to $6.636 billion, the company said.

Extensions to the in-service date beyond August 31 are estimated at about $25 million to $35 million per month.

Compared to the $2.2 billion originally estimated in 2004, total costs for the project—a first of its kind—have now almost tripled.

First-of-a-Kind Pains

Mississippi Power spokesman Jeff Shepard told POWER on February 3 that the project has progressed into an operational testing phase.

“While these tests have confirmed the design of these first-of-a-kind systems, we have also identified some modifications, rework and needed repairs that will be implemented and re-tested before these systems can be placed in service. This is not unexpected for systems being commercialized for the first time.”

One example occurred during start-up and testing of the gasifiers, while workers were curing out (“like pottery in a kiln,” Shepard explained) the refractory on Gasifier A and discovered hotspots on the gasifier steel. “Several cracks and gaps in the hard face layer caused fluidization sand and gas to unexpectedly erode the soft layer during the fluidization test this past fall. To repair and replace the soft layer, we must also remove and repair the hard face layer,” he said. “Performing these very deliberate start-up and testing activities allows us to identify issues and correct them before we begin testing the gasifiers with lignite coal.”

Workers are not preparing for fluidization tests on Gasifier B, using lessons learned from the tests on Gasifier A.

“The sand feed test is a precursor to injecting lignite into the gasifier,” Shepard said. “The sand feed test, or fluidization, on Gasifier A produced very good results indicating no issues with the fluidization aspects or performance testing of the gasifier. However, during the curing, or drying out, of Gasifier A’s refractory lining, issues were identified that are being corrected in Gasifier A and are also being addressed in Gasifier B before testing begins.”

The next step after successful testing of the gasifiers will be to feed lignite into the gasifiers, he said.

Sonal Patel, associate editor (@POWERmagazine, @sonalcpatel)