Details

Autor(en) / Beteiligte

• Kjær, S.
• Bugge, J.
• Frandsen, R. B.

Titel

Advances in super critical power generation 2006

Ist Teil von

• Energy materials, 2006-06, Vol.1 (2), p.136-142

Erscheinungsjahr

2006

Link zum Volltext

Quelle

Taylor & Francis Journals Auto-Holdings Collection

Beschreibungen/Notizen

• European efforts to start substantial improvements of the performance of well established supercritical coal fired power technology named the AD700 project started in the mid 1990s. Major targets were development of austenitic materials and nickel based superalloys for the hottest sections of boilers, steam lines and turbines. Other targets were development of boiler and turbine designs for the more advanced conditions and finally economic viability of the AD700 technology has been investigated. The project has been very successful and 40 partners from the European power industry have worked together in several projects cofunded by the European Commission for > 10 years. Procurement of mature and commercially optimised AD700 plant could take place around 2015. The investigated nickel based materials have shown very high creep strengths but they have also shown to be very hard to manufacture, and more efforts to define new machining lines are being started. Ongoing tests indicate that the developed austenitic material will fulfil its creep strength target and is now ready for commercialisation. Development works on boiler and turbine designs for the advanced steam conditions have also been successfully completed but they also clearly indicate that further development work on improved ferritic steel for furnace walls is important. Conventional development of the steam cycles is based on new improved materials, which open for higher steam temperatures and efficiencies whereas other thermodynamic tools are only slowly being accepted. However, in the present paper a proposal for steam cycle improvements not based on higher steam temperatures is presented. The improved cycle is named the master cycle (MC) and it is based on a revision of the double reheat steam cycle where the bleeds of the intermediate pressure (IP) turbines have been moved to a feed pump turbine bleeding on the first cold reheat line. Elsam has established protection of a patent for the MC in a number of countries. At constant main and reheat steam temperatures, the MC offers solid heat rate improvements of ~3*5% compared with single reheat cycles and a seawater cooled plant based on the MC could reach a net efficiency of 50%. This would mean robust improvement of competitiveness, less CO2 per MW h being generated and a more sustainable use of the coal resources. In the future, the net efficiency will continue to increase and a sea water cooled 800 MW AD700 power plant to start commercial operation around 2020 might reach a net efficiency around 55% based on the MC. However, pressure on energy resources will continue and even increase in future, so that the need for more effective and sustainable power stations will also continue, and there are no signs that development of more advanced materials and water/steam cycles will stop in foreseeable future.