Upgraded Siemens gas turbine portfolio for the distributed power market

In a 2x1 combined cycle configuration the power output is 150 MW at a net efficiency of more than 56%. It retains the same dry low emissions (DLE) system, capable of achieving NOx levels below 15 ppm and CO emissions below 5ppm. The upgraded turbine will be offered in addition to the two current SGT- 800 versions, with power outputs of 47.5 MW and 50.5 MW respectively. Contracts for the first six 53 MW units have already been signed, says Siemens, and will be delivered to customer sites in the course of 2016.

As of June 2015, some 270 gas turbines of the SGT-800 type had been sold worldwide and the fleet had accumulated more than three million operating hours, Siemens reports. The 50.5 MW units first entered commercial operation in 2011 and more than 80 units of this version have been sold worldwide. The 53 MW version "follows the design philosophy of taking small evolutionary fine-tuning steps", Siemens says.

The 53 MW rating has been achieved through optimised and re-staggered first compressor stages, which increase both efficiency and mass flow, optimised cooling layout of turbine guide vanes, and adjusted clearances in turbine stages 1 and 2.

Minor machining modifications to four stationary components have been required to exploit the performance tuning potential in the turbine section. No changes have been made to castings or materials and the outlet temperature from the combustor remains the same. All improved components are fully retrofittable into the existing 50.5 MW series.

The full range of Siemens offerings for the distributed generation market (consisting of gas turbines from 4 to 66 MW) is shown in the table below.

The portfolio now has the benefit of aeroderivative machines, thanks to the acquisition of the gas turbine and compressor business of Rolls-Royce Energy, completed in December 2014. Siemens calls these new additions to its offerings the Industrial RB211 and the Industrial Trent (dropping the Rolls-Royce name).

According to Wolfgang Konrad, CEO for Distributed Generation, Siemens, about 25% of the distributed power market can only be addressed with aeroderivatives, and that "underlines how it was important to acquire Rolls-Royce Energy because with that we can truly supply the whole market with tailored products".

Speaking at a Siemens press event in June at Power-Gen Europe, Amsterdam, he emphasised that the acquisition not
only gives Siemens current Rolls-Royce aeroderivative technology but also 25 years of its future technology. "We didn't just buy what they have today, but what they are going to develop in the future", giving Siemens "access to high end aeroderivative technology."

Packaging agreement with Centrax extended

Meanwhile, Siemens has extended its packaging agreement for gas turbines with Centrax Ltd, so that it now totals 31 European countries.

Since June 2011, Centrax has been selling the SGT-300 and SGT-400 gas turbine series from Siemens as a complete generating set package under the Centrax product names CX300 and CX400.

Siemens initially established a packaging partnership agreement with Centrax for the SGT-300 and SGT-400 gas turbine series for Belgium, France, Italy, the Netherlands, and the United Kingdom. The agreement has now been expanded to 26 additional countries: Austria, Bulgaria, the Czech Republic, Cyprus, Denmark, Estonia, Finland, Germany, Greece, Hungary and Ireland. Furthermore Latvia, Lithuania, Luxembourg, Malta, Norway, Poland, Portugal, Romania, Sweden, Slovakia, Slovenia, Croatia, Spain, Switzerland, and Turkey.

For the European market, Centrax has therefore become the primary route to market for industrial power generation and distributed energy packages employing the Siemens SGT-300 and SGT-400 gas turbines.