SGT6-9000HL heavy-duty gas turbine (60Hz)

Pushing efficiency and performance to the next level

    drag to rotate

    Proven single tie bolt rotor. Rotor air cooler allows proven steel disc design

    Hydraulic Clearance Optimization (HCO) - reduced degradation and clearance losses

    Advanced combustion system for high efficiency (ACE) with dual fuel capabilities

    12-stage, third generation harmonized compressor, evolutionary 3D blading

    Innovative multi-layer coating for blades and vanes for better blade robustness

    Super-efficient internal cooling features for blades and vanes

    Large free-standing turbine blade 4 for higher power output

    4-stage turbine: high cycling capability through fully internal air-cooling

    Simple cycle output (ISO) 388 MW(e)

    Combined cycle efficiency: > 63%

    Derived from proven
    Siemens H-class technology

    The next generation of Siemens advanced air-cooled gas turbines

    Siemens HL-class gas turbines are paving the way to the next level of efficiency and performance. Derived from proven Siemens H-class technology in an evolutionary development step, the next generation of Siemens advanced air-cooled gas turbines uses a series of new, but already tested technologies like super-efficient internal cooling features for blades or vanes and an advanced combustion system to increase firing temperature.


    The result:

    A technology carrier to the next level with a combined cycle efficiency beyond 63% that will clear the way to the next level with a midterm goal of 65%. The new Siemens HL-class consists of three engines: SGT5-8000HL, SGT5-9000HL and SGT6-9000HL.

    Press release for the Siemens HL-class
    Download press release

    Highlights of the Siemens SGT6-9000HL

    The gas turbine is capable of world-class fast cold starts and hot re-starts due to the light and stiff rotor with internal cooling air passages and free thermal expansion of rotor and casing parts during transients. Hydraulic Clearance Optimization (HCO), an active clearance control,  ensures robustness and low turbine degradation at start-up. GT ramp-up rate 85 MW/min.

    The advanced can-annular combustion system with dual fuel capability allows for higher firing temperatures and more operational flexibility. 25 premix burners improve the fuel/oxygen mixing. The ACE combustion system allows for GT turn-down to 30% GT load.

    All turbine blades and vanes are equipped with an innovative multi-layer thermal barrier coating. This leads to higher combined cycle efficiency due to less cooling air consumption and reduced operational costs due to higher blade robustness.

    The HL-class has been designed to minimize outage times. Rotor de-stacking can easily be done on site thanks to the Hirth-serrated disc assembly. All rotating compressor and turbine blades can be replaced without rotor lift or rotor de-stacking. Turbine blade 1 and turbine blade 4 are removable without cover lift. With 33kEBH service intervals the service concept is very competitive.

    Due to proven and validated package and plant concepts the HL-class can easily be integrated in our power plants for simple cycle or combined cycle operation. This enables fast project execution. More than 50,0000  hours are saved on site due to modularized design and pre-engineered solutions.

    The new HL-class is based on the reliable engine architecture of the SGT-8000H series with design features that have proved reliability in operation for years:

    • Hydraulic Clearance Optimization (HCO)
    • Single tie bolt with Hirth serration
    • 4-stage air-cooled turbine
    • Can-annular combustion system

    When experience meets evolutionary innovation

    Based on proven design and relying on the vast fleet experience of the SGT-8000H series, the new Siemens SGT6-9000HL combines the best of past experience with newly developed technologies. Thus, efficiency and performance are pushed to the next level.
    The new Siemens HL-class – a portfolio consisting of three engines: SGT5-9000HL, SGT6-9000HL and SGT5-8000HL. A modular design approach allows for a substantial number of common parts.



    Siemens HL-class is designed for high operational flexibility and has a joint DNA with the proven Siemens H-class:

    • Air-cooled 4-stage turbine
    • Steel rotor / Hirth serration / single tie bolt design
    • Hydraulic Clearance Optimization (HCO)
    • Can-annular combustion system



    Tested technologies for higher efficiency and performance

    To achieve top performance and efficiency levels, the HL-class turbines are operating at highest combustion temperatures with an advanced combustion system.
    An innovative multi-layer thermal barrier coating and super-efficient internal cooling features are protecting turbine blades and vanes while reducing the need of cooling air.
    Additionally, advanced 3D blading leads to higher aero efficiency in the compressor.  A free-standing, internally cooled turbine blade 4 reduces exhaust losses and allows for higher exhaust temperatures to enhance the water-steam cycle.



    Plug-and-Play power core

    Siemens has re-invented the methodology for plant construction with a modular Power Core™.

    The Power Core™ consists of prefabricated Siemens Solution Blocks and prefabricated pipe racks. These plug-and-play blocks are fabricated and tested in a controlled manufacturing environment and delivered to site as large modules which can be lifted into place for assembly. This results in increased safety on site, accelerated schedules, less dependence on the availability of skilled local labor and in the end lower project risk.




    HL-class power plants are based on one or more HL-class gas turbines and can achieve more than 63% efficiency in combind cycle operation:


    SCC5-9000HL 2x1: 1,682 MW

    SCC6-9000HL 2x1: 1,154 MW

    Designed for low maintenance costs and short outage times

     All components are designed with high focus on optimized LCOE, highest availability and serviceability. Several service features are supporting this.

    • All rotating blades replaceable without rotor lift/rotor de-stacking
    • Easy rotor de-stacking on site due to disc assembly with Hirth serration and central tie rod
    • All turbine vanes and blades replaceable without rotor lift; vane 1, blades 1 & 4 replaceable without cover lift


    Tremendous service fleet experience and continuous development result in a competitive service concept with 33,000 Equivalent Base Hours (EBH) / 1,250 Equivalent Starts (ES).



    Designed to fullfil environmental requirements

    While reaching highest levels of performance and efficiency, the HL-class is still complying with NOX and CO regulations.

    NOX emissions: Down to 2 ppmvd (with SCR)

    Technical data

    Technical data for the SGT6-9000HL

    Performance data for simple cycle power generation

    Download table as: PDF Excel
    Power output
    405 MW(e)
    Fuel (examples) Natural gas, LNG, distillate oil. Other fuels on request
    Frequency 60 Hz
    GT ramp-up 85 MW/min
    Gross efficiency 42.6%
    Heat rate 8,451 kJ/kWh (8,010 Btu/kWh)
    Turbine speed 3,600 rpm
    Pressure ratio 24.0 : 1
    Exhaust mass flow 725 kg/s (1,598 lb/s)
    Exhaust temperature 670°C (1,238°F)
    NOₓ emissions down to 2 ppmvd with SCR, down to 25 ppmvd without SCR
    CO emissions 10 ppmvd

    Simple cycle ratings are gross values at ISO ambient conditions. Actual performance will vary with project-specific conditions and fuel.

    Performance data for combined cycle power plant

    Download table as: PDF Excel
    SGT6-9000HL CC 1x1/1S
    SGT6-9000HL CC 2x1
    Frequency 60 Hz 60 Hz
    Net plant power output 595 MW 1,190 MW
    Net plant efficiency > 63% > 63%
    Net heat rate < 5,714 kJ/kWh (< 5,416 Btu/kWh) < 5,714 kJ/kWh (< 5,416 Btu/kWh)
    Number of gas turbines 1 2
    Pressure/reheat Triple/Yes Triple/Yes
    Steam temperature > 600° C (> 1,112° F) > 600° C (> 1,112° F)

    Combined cycle ratings are net values at ISO ambient conditions. Actual performance will vary with project-specific conditions and fuel.

    Physical dimensions and weight

    Download table as: PDF Excel
    Core turbine
    Approx. weight 305,000 kg (672,400 lb)
    Length 10.8 m (35.4 ft)
    Width 5.0 m (16.4 ft)
    Height 4.3 m (14.1 ft)

    Siemens HL-class gas turbines


    *ISO/gross/natural gas

    Download the infographic as PDF
    Download infographic

    Pushing efficiency and performance to the next level

    Based on proven technology and relying on a vast fleet experience, the Siemens HL-class combines technologies and design features from the SGT-8000H, SGT-5000F and SGT-4000F product families.

    Interactive VR experience

    Explore the HL-class in virtual reality

    Downloads and support

    Find out more about our gas turbine offerings

    In our download section, you can find brochures, technical papers, and more. Or you can contact us directly for specific inquiries.

    For more information, please contact our Customer Support Center.

    Siemens AG
    Freyeslebenstrasse 1
    91058 Erlangen

    (Charges depending on provider)
    (From the German fixed network € 0.14/min.
    and from the German mobile phone networks
    max. € 0.42/min.)


    Siemens HL-class gas turbines are based on proven H-class technology

    Around 60 Siemens H-class turbines in commercial operation, with about 650,000 fired fleet hours. Overall, more than 85 units are under contract.




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