Performance of gas-fired power station verified and optimised
On behalf of Siemens, TÜV SÜD carried out extensive performancetests on the state-of-the-art combined-cycle power station.
Combined-cycle gas and steam turbine power plants offering excellent operational flexibility and efficiency are in rising demand to offset fluctuations from the grid feed-in of energy from renewable sources. In these plants, the exhaust emitted by the gas turbine is passed into a downstream waste-heat boiler where it is used to produce steam, which then, in turn, is converted into electricity in a steam turbine.
On behalf of its client DONG Energy, Siemens built the turn-key combined cycle power station Severn Power in Uskmouth, Wales, UK. The plant comprises two single-shaft units, with the main components (gas turbines of the type SGT5-4000F, SST5-5000 steam turbines and the generator) being arranged in a single line of shafting. With a total capacity of 834 MW and offering excellent efficiency of 58 per cent, the Severn Power power station supplies over 1.5 million households with clean energy.
Verification of contractual guarantees
Performance testing and verification of guaranteed conditions carried out on new plants serve to provide third-party corroboration that the supplied components comply with the contractually agreed parameters of performance. At the same time, the data are used as a basis for determining the optimum operation of the plant. This was also the case at the Severn Power combined-cycle power station. Siemens Energy Sector commissioned TÜV SÜD to carry out an extensive measurement campaign.
Precise measurement and adjustment of the performance parameters of the main components, the gas turbine, the waste-heat boiler and the steam turbine, proved particularly challenging. The ideal settings for plant operation were determined in a tuning procedure in which calibrated high-precision measurement instruments were positioned at a large number of measurement points.
"The plant outperforms the warranted performance parameters required by our client throughout all aspects", says Lothar Balling, Head of GT Power Plant Solutions in the Fossil Power Generation Division of Siemens Energy Sector. "It is also impressive proof that security of supply, profitability and sustainability can go hand in hand."