Ceramic Stationary Gas Turbine Development Program — Seventh Annual Summary

Abstract

The Ceramic Stationary Gas Turbine (CSGT) program is being performed under the sponsorship of the United States Department of Energy, Office of Industrial Technologies. The objective of the program is to improve the performance of stationary gas turbines in cogeneration by retrofitting uncooled ceramic components into the hot section of the engine. The replacement of previously cooled metallic hot section components with the uncooled ceramics enables improved thermal efficiency, increased output power, and reduced gas turbine emissions. This review summarizes the progress on Phase III of the program, which involves field testing of the ceramic components at cogeneration end user sites. The Solar Centaur 50S engine, which operates a turbine rotor inlet temperature (TRIT) of 1010°C (1850°F), was selected for the developmental program. The program goals include an increase in the TRIT to 1121°C (2050°F), accompanied by increases in thermal efficiency and output power. This will be accomplished by the incorporation of ceramic first stage blades and nozzles, and a “hot wall” ceramic combustor liner. The performance improvements are attributable to the increase in TRIT and the reduction in cooling air requirements for the ceramic parts. The “hot wall” ceramic liners also enable a reduction in gas turbine emissions of NOx and CO. The component design and material selection have been definitized for the ceramic blades, nozzles and combustor liners. Each of these ceramic component designs was successfully tested in short term engine tests in the Centaur 50S engine test cell facility at Solar. Based on their performance in a 100 hour cyclic in-house engine test, the ceramic components were approved for field testing. Oxidation of the ceramic components in the gas turbine environment dictated the need for environmental barrier coatings, which were optimized under the program. To date, six field installations of the CSGT Centaur 50S engine totaling over 14,000 hours of operation have been initiated under the program at two industrial cogeneration sites. An 8000 hour field demonstration of a low emission ceramic combustion system was initiated in August 1999. This paper briefly discusses the recent developmental efforts for the ceramic components, but focuses on the various field demonstrations.