Siemens Energy has achieved a major milestone for its HL class engine by successfully starting the first installation of the GT, on April 6, at Duke Energy’s Lincoln Combustion Turbine Station near Denver, in the USA.
The HL-class engine architecture consists of an air-cooled four-stage power turbine, hydraulic clearance optimisation for higher efficiency at full load while facilitating immediate restart, a service-friendly steel rotor design with Hirth serrations and a central single tie rod and a can annular combustion system.
First fire confirms that the engine and its auxiliary systems – including the gas supply, lube oil system, control system and startup systems – are working together as designed.
During first fire, the SGT6-9000HL ramped up to a pre-determined test speed, and the combustion system ignited.
In November 2019, Siemens delivered the 402 MW unit from its manufacturing plant in Charlotte to Duke Energy’s Lincoln station, where workers lifted the 340-ton turbine onto its foundation.
After the first phase of testing is completed, the SGT6-9000HL will continue its four-year testing plan (2020-2024), gradually introducing technologies to achieve the next level of efficiency.
The unit will be operated in simple-cycle mode under real-world power plant conditions, allowing Siemens to continually assess and optimise the performance while gaining valuable commercial operating experience.
The turbine’s ramp-up rate is about 85 MW/min, a speed that should facilitate operational flexibility and integration with fluctuating renewable generation. With increased inspection intervals of 33 000 equivalent base-hours and 1 250 equivalent starts, the unit, says Siemens, will also provide outstanding reliability and lower life-cycle costs.
When all testing is completed in 2024, Siemens will turn the unit over to Duke Energy. It will be the most efficient of its type in Duke Energy’s fleet. Investing in natural gas technology will also help Duke Energy close coal plants faster and reach its aggressive goals for cutting carbon emissions by at least 50% by 2030.