A new Siemens gas turbine operated in a combined cycle with a steam turbine in Irsching, Bavaria, has set a world record for efficiency, achieving net efficiency of 60.75% during the test run. The target was 60%; the previous generation of the turbine had an efficiency of 58.5%. The new turbine is designed to generate 400 megawatts (MW) alone and 600 MW when combined with a steam turbine.
In tests conducted under everyday conditions the facility was able to supply more than 500 MW within just one half hour. With the rise of a fluctuating electricity supply from wind turbines and solar power systems, maintaining the power grid’s stability is a job handled by large power plants that can quickly respond and offset changing loads, Siemens noted.
The new facility is also much more economical than previous plants. The new generation of Siemens combined cycle power plants consumes one-third less natural gas per generated kilowatt-hour than what is used on average by other such facilities currently in use worldwide.
Siemens attributed the performance to the interplay of innovative gas turbine technology and the plant’s key components, which are optimized for high temperatures and pressures. Each turbine consists of more than 7,000 individual parts. The 50-hertz version weighs 440 tons, as much as a fully-fueled Airbus A380. Temperatures within the combustion chamber can be as high as 1,500 degrees Celsius, and the turbine blade tips can rotate at more than 1,700 kilometers per hour (km/h).
More than 750 Siemens employees, including 250 engineers, were involved in the development of the turbine and the new combined cycle power plant. The company invested over €500 million (US$695 million) in the development, construction, and operation of the prototype facility in Irsching. Siemens thoroughly tested the gas turbine over a period of one and a half years, and in mid-2009 it began retrofitting the facility for steam turbine operation. After the testing stage is completed, E.ON will begin commercial operation sometime this summer.