A First In China For Siemens

Siemens has received its first order from China of SGT-800 gas turbines and the associated generators.

The four turbines will be installed in the Shanxi Guoxin Baode and Xiyang decentralized energy projects in Central China. The two combined cycle power plants with heat extraction will have an overall capacity of 308 MW. The customer is Shanxi Natural Gas Ltd. Co., a subsidiary of Shanxi Provincial Guoxin Energy Development Group Co., Ltd. Commercial operation of the plants is scheduled for July 2017.

Two gas turbines and two generators are to be installed in a 2×1 combined cycle power plant with heat extraction at each site. Siemens will also supply all associated auxiliary systems as well as installation and commissioning services for the projects. Both combined cycle power plants will be fired with coalbed methane, a form of natural gas from an unconventional gas reservoir with high hydrogen content. The SGT-800 is able to fire this gas due to its high fuel flexibility, Siemens said.

“This first order of SGT-800 gas turbines is a breakthrough success for us on the fast developing Chinese decentralized energy market,” said Yao Zhen Guo, country division lead for Power and Gas and Wind Power and Renewables in China. “As a trustworthy partner, we are happy that we can support Guoxin Energy with world leading gas turbine technologies.”

Worldwide, 297 SGT-800 gas turbines have been sold and the fleet has accumulated about 4 million operating hours, Siemens said. The efficiency and steam-raising capability of the SGT-800 makes the turbine especially suitable for cogeneration and combined cycle applications. The high reliability and high efficiency of the gas turbine promote both a low life-cycle cost and a small environmental footprint.

According to China’s 12th Five-Year Plan for Renewable Energy Development, China will pay high attention to develop the decentralized energy market, especially fueled by natural gas. Siemens supports these ambitious goals with the delivery of gas turbines for the Shanxi Guoxin Baode and Xiyang power plants.

The SGT-800 gas turbine is available in three versions with power output of 47.5, 50.5 and 54.0 MW respectively.

The SGT-800 is a single-shaft machine with 15 compressor stages. The first three stages have variable guide vanes. To minimize leakage over the blade tips, abradable seals are applied to stages four to fifteen. The three-stage turbine is built as one module and is bolted to the compressor shaft to provide for easy maintenance. The turbine stator flanges are air-cooled to reduce running clearances and improve efficiency. The overall design of the SGT-800 gas turbine ensures easy service access to the combustor and the burners, Siemens said. The cold end of the gas turbine is connected to the generator via a reduction gear unit; this reduces the turbine speed from 6,600 rpm down to 1,500/1,800 rpm. The SGT-800 gas turbines are equipped with Dry Low Emissions (DLE) combustion system to reduce nitrogen oxide emissions. The combustion system is designed to operate on both gas and liquid fuels and it’s capable of on-line switchover between fuels.