GE Installs Its Newest Steam Turbine Technology for North Dakota Power Plant

BALTIMORE, MD - May 2008 : – GE Energy has applied its latest steam turbine technology to enhance the reliability and overall performance of North Dakota’s largest power plant, Great River Energy’s Coal Creek Station, located 50 miles north of Bismarck.

As announced today at the 2008 Electric Power Conference, the Coal Creek Station project marks the first installation of GE’s new 26.8-inch last stage bucket (LSB) with axial entry dovetail. The technology has been developed to help power plants remain competitive by increasing the output and reliability of the low-pressure sections of steam turbines.

The new GE 26.8-inch LSB was applied to the first of the two GE steam turbines at Coal Creek Station, which has a total generation capacity of more than 1,100 megawatts. The section replacement was completed in April 2008 with the unit re-entering commercial service in May 2008.

The country’s aging fossil steam turbine fleet is faced with challenges including reliability and the need to enhance performance to offset the power used for new environmental control equipment. The low-pressure section alone is responsible for delivering approximately 50% of the steam turbine output.

“To improve current performance and reliability, GE has introduced a replacement of the original 26-inch LSB steam path design with a new steam path featuring the 26.8-inch active length LSB,” said Steve Pock, Steam Turbine Product Manager at GE Energy. “With an increased annulus area and reduced exhaust losses, the longer LSB is designed to increase plant output without increasing heat to the turbine or fuel to the boiler.”

“Since unit 1 started generating electricity in 1979, Coal Creek Station has been cited in several national rankings as one of the nation’s most reliable and cost-efficient steam turbine power plants,” said Mark Ness, Principal Engineer of Great River Energy. “This project, featuring GE’s new LSB technology, is a key part of our strategy to continue that high level of performance.”

The 26.8-inch LSB is part of GE’s on-going development of turbine enhancement and parts replacement programs to help extend outage intervals. GE has supplied highly advanced steam turbine technology to customers worldwide for more than a century.