About 50 miles northeast of Louisville, Ky., in a rural district along the banks of the Ohio River is the Trimble County power station. As the 2012 COAL-GEN Conference and Exhibition got underway in Louisville on Aug. 14, about 20 attendees visited the Trimble County station, home to two large coal-fired units and six combustion turbines. Louisville Gas and Electric (LG&E) and Kentucky Utilities (KU), both PPL (NYSE: PPL) companies, own and operate the plant situated on about 2,200 acres. The plant’s two coal-fired units, TC1 and TC2, are also jointly owned by the Illinois Municipal Electric Agency and the Indiana Municipal Power Authority.
The station is home to six GE (NYSE: GE) 7FA simple-cycle, natural gas-fired combustion turbines, used primarily for peaking. But the focus of the tour was the coal-fired units. In commercial operation since 1990, TC1 is a subcritical unit that uses Eastern Bituminous coal to generate about 514 MW. Even though TC1 is a reliable unit that LG&E Trimble Country employs are proud of, the star of the tour seemed to be TC2, LG&E’s newest unit. TC2 is a supercritical unit that generates 760 MW firing on a blend of Eastern Bituminous and Western Sub-bituminous (PRB) coal. After receiving permission from the Kentucky Public Service Commission in 2005, LG&E broke ground on the new coal-fired unit in August 2006. After about four years, the unit is now in an ‘interim operation’ mode as the operators deal with problem with the combustion system, according to Plant Manager Tom Crutcher. While the plant is not fully commissioned, Crutcher said the power is dispatchable.
What caught the eye of COAL-GEN 2012 attendees was the uniqueness of the plant and the amount of environmental controls at TC2.
“Not many units have the arrangement of Unit 2,” said Crutcher.
Twenty-five percent of the total cost of TC2 was spent on environmental-related equipment. TC2, as well as TC1, is equipped with low NOX burners, selective catalytic reduction which remove about 90 percent of its inlet NOX, dry electrostatic precipitators, and wet limestone flue gas de-sulfurization which can remove 98 percent of its inlet S02. TC2 is also equipped with powdered activation carbon injection and a pulse jet fabric filter for mercury removal, as well as a wet ESP for fine acid mist removal.
Crutcher, who has worked at the Trimble County plant since 1998, said a lot of construction activity has been taking place over the past 10 years as the utility upgraded Unit 1, and constructed Unit 2. And safety at Trimble County is at the fore-front. The plant has not had an Occupational Safety and Health Administration (OSHA) reportable incident or lost time injury in about three years.
“We are looking for a lot of years of operation out of Trimble County,” said Crutcher.
Look for more on the Trimble County power station in the “Managing the Plant” section in the September issue of Power Engineering magazine.