Increasing efficiency in power plant engineering is a hot topic. This technologically challenging endeavor of increasing conventional steam temperatures of 600°C up to 700°C is the requirement and the goal of the project COMTES700. The abbreviation stands for "Component Test Facility for a 700°C Power Plant". It is sponsored by the European Union and involves HORA as one of the technology partners: The power of innovation from Schloß Holte-Stukenbrock.
Raising steam temperature from 600°C to 700°C and achieving thermal efficiencies of over 50% is a major step. Increased efficiency of the power plant can be easily explained with physics. The hotter the steam entering the turbine, the more heat energy the turbine blade can transform into rotational energy and feed into the generator. At the same time, it reduces the quantity of coal per kilowatt of generated electricity and the CO2 emissions. At the present time, coal-fired power plants around the world currently emit about eight billion tons into the atmosphere every year.
Extreme challenges for the materials
In contrast to the relatively easy explanation of the effect of higher steam temperatures, an explanation of the technical implementation is much more difficult. An increase in temperature from 600°C to 700°C with a simultaneous increase in the pressure up to 350bar requires a new class of material. The ones used today cannot permanently withstand these conditions. New materials for pipes, valves and other components for power plant engineering are necessary. These new materials have been developed in the form of new and extremely expensive nickel-based alloys, which are then processed at HORA for manufacturing power plant control valves suitable for operation at 700°C.
1.8 tonnes of innovation from HORA
We are the first valve manufacturer worldwide to supply control valves featuring these new parameter extremes in power plant technology. The first of these components was delivered for tests in 2005. Positive experience with the pilot projects prompted E.ON to invite the 700°C specialists from HORA to design and test a high pressure bypass valve for large technical applications. The 700°C valve developed by us based on the new, high-performance materials "was a Formula 1 project in power plant engineering", says Franz Hansknecht, head of Production Innovation at HORA Power Technology. The knowledge and experience from this technology also enables us to meet the challenges of conventional power plant engineering.