Two GE Heat (high efficiency, advanced technology) steam turbines have surpassed 20,000 hours of operation at power plants in California and Ireland, GE Energy reported at Power-Gen International 2008. The achievement is regarded by the company as an industry milestone for proving reliability of the turbines.
Introduced in 2002, the GE Heat steam turbines improve plant efficiency and output for GE's F-class combined-cycle technology, leading to a lower cost of producing electricity, a critical factor for success in today's power generation industry. Seven of the Heat steam turbines currently are in commercial operation in natural gas-fired, combined-cycle power plants in the United States and Europe, encompassing both 60-hertz and 50-hertz applications.
One of the ‘milestone' Heat steam turbines is operating as part of a 60-hertz, GE 107FA combined-cycle system at the Southern California Public Power Authority (SCPPA) Magnolia facility in Burbank, California. Since entering commercial operating in 2005, this unit has compiled 20,170 hours of reliable service as of mid-November, while also exhibiting dependable start-up capabilities.
The second Heat steam turbine to surpass the 20,000-hour milestone is installed at the Tynagh Energy Plant in County Galway, Ireland. This plant is supplying up to 120,000 homes with reliable electricity and is helping change the economic face of Galway and the western seaboard of Ireland.
The Heat steam turbine incorporates numerous advancements over earlier GE steam turbines, including a reaction-based high-pressure turbine design capable of 2400 psi operating pressure, which contributes to improved steam turbine performance. Integral covered buckets and nozzles ensure a high-quality steam path.
Abradable coating and brush seals developed in conjunction with the GE Global Research Center minimise internal leakage while maintaining tight clearances. Extensive analysis and validation testing prior to its first application helped ensure the reliable operation of the Heat technology.