Siemens has started field trials of its next generation gas turbine technology. Following component testing and prototype testing in its own facilities, the company is now pursuing validation under real field conditions with the start of testing of its HL-class technology at Duke Energy’s Lincoln County site in North Carolina.
Siemens describes the technology as an evolutionary development step derived from its SGT-8000H model. The HL-class is said to combine ‘a series of new but already tested technologies and design features with the best of past experience’– resulting in a technology carrier to the next level of efficiency and performance.’ The development of the HL-class is ‘clearing the way to efficiency levels beyond 63 % with a mid-term goal to reach 65 %’. The intention is ultimately to transfer newly developed key technologies to the company’s entire gas turbine portfolio. Siemens will also work towards significantly reducing lead and construction times through standardisation and modularisation.
The new HL-class consists of three engines: SGT5-9000HL, SGT6-9000HL and SGT5-8000HL. In simple-cycle operation the air-cooled SGT-9000HL gas turbine will produce 545 MW at 50 Hz and 374 MW in the 60 Hz version. SGT5-8000HL will provide 453 MW in simple-cycle operation. All engines should achieve greater than 63% combined cycle efficiency.
To achieve this performance, the turbines operate at high combustion temperatures. For this purpose, Siemens has developed advanced combustion technologies, innovative multi-layer coatings, highly efficient internal cooling features and an optimised water-steam cycle. It has also optimized seals to minimise cooling and air leakage. At the same time, evolutionary 3D blading is enabling higher aero-efficiency for the compressor.
A modular design will allow predefined and prefabricated elements to significantly reduce construction time and provide a fast start for projects. The turbines are designed to plug in to Siemens’ digital offering for plant operators and utilities alike, incorporating connectivity to MindSphere, the cloud-based operating system for the Internet of Things. MindSphere offers access to powerful analytics.
“Driven by digitalisation, speed in technology development is rapidly gaining momentum in the power generation arena,” said Willi Meixner, CEO of the Siemens Power and Gas Division. “It took us 10 years from 2000 to 2010 to increase the efficiency of our combined cycle power plants from 58 to 60%, a further six years to reach 61.5% in 2016 and now we are taking the next step to 63% and beyond. But we know that speed and efficiency alone are not sufficient – reliability and cost effectiveness of our solutions as well as partnership, support in financing and insurability are also key to our customers”.