Technological trends in gas turbine development

Given the fast-paced increase in the worldwide demand for electricity, especially in Asia, the need for high-efficiency large-capacity environmentally friendly power generation facilities is seeing greater recognition. Against this backdrop, high-efficiency combined-cycle plants, which combine high-temperature gas turbines with steam turbines that are driven by the steam generated using the gas turbine exhaust, have moved into the spotlight. Such plants are considered to be an important technology in the field of power-generating plants. Ever since Hitachi, Ltd. introduced the H-25 high-temperature gas turbine featuring a 1260°C combustor exhaust port, the first of its kind, it has developed, manufactured, and delivered a total of six 1300°C-class gas turbines using rotors manufactured by U.S. -based GE, including the latest model F7FA with a capacity of 159 MW. Additional 11 units are currently under production. Given the success of these systems, Hitachi has been forging ahead with the development of key technologies aimed at helping to bring the next-generation high-temperature gas turbines to the marketplace. These technologies include the use of high temperature alloys, high-performance cooling technology, high-performance aerodynamic design technology, and dry low-NO x combustion technology.