Abstracts - VGB PowerTech Journal 11/2005

Sustainable Maintenance Strategies for Power Plant Operators

Ulrich Gräber and Eberhard Roos

An important parameter of the end price of electricity, which can be influenced by the power plant operators is maintenance. With the aim of reducing the maintenance costs, during the past few years condition-based or risk-based maintenance strategies were applied. Maintenance expenditure can be optimally adapted through determination, as exactly as possible, of the respective aging state. Maintenance expenditure can only be lowered on a sustainable basis with strategies applied in the long-term.

Fluidised-bed Technology for the Capacity Range 400 to 600 MW

Georg-N. Stamatelopoulos and Joachim Seeber

Steam generators with circulating fluidised- bed combustion (CFB) have found a wide area of application throughout the world over the last years, in particular for the power generation, but also as industrial power plant and combined heat and power stations. Today, more than 500 plants are in operation or under construction for the capacity range from 50 up to over 400 MW. Power plants with a capacity range from 400 up to 600 MW are currently under develpoment. Parallel to the capacity increase of CFB plants the efficiency and the availability of conventional pulverised coal-fired plants was further increased.

Ultra-supercritical Steam Turbine Turbosets – Best Efficiency Solution for Conventional Steam Power Plants

Andreas Wichtmann, Mathias Deckers and Wilfried Ulm

Today's power generation markets are characterized by rising energy consumption, increasing oil and gas prices and moderate increasing coal prices. The ultra supercritical fossil power plant is an economical and ecological option for high-efficiency and low-emissions electricity generation. The steam conditions put new requirements on the steam turbine turboset. Demands and design solutions on the ultra supercritical steam turbine are presented for component design, sealing technology, blade path set up and material perspective.

Application of “Fogging“ to Increase the Output of Stationary Gas Turbines

Wulf Kraneis

Fogging systems in air filter houses of stationary gas turbines have been applied for approximately eight to nine years in order to cool the combustion air. These coolers are employed to increase the output of gas turbines and combined cycle plants. The system is based on evaporation cooling that is achieved through cascades. An increase of up to 15 % – depending on the location of the plant – is possible.

Production of Hydrogen Rich Fuels in IGCC Processes for Lignite Use with Minimal CO₂-emissions

Dipl.-Ing. Katrin Ogriseck and Professor Bernd Meyer

Reduction of CO₂-emission and increase of efficiency are the essential demands for a future, sustainable energy supply based on lignite. The central production of hydrogen-rich, liquid or gaseous fuels in IGCC plants and the decentral usage of these fuels in combined heat and power plants is a promising option for clean and efficient lignite conversion. Three IGCC-power plant concepts for central production of a hydrogen-rich fuel (methanol, hydrogen, synthetic natural gas) from lignite are presented.

Training Concept Resulting from Challenge of Competition

Markus Bieder

The liberalisation of the electricity market together with the consequential competition has lead to pressure on the energy suppliers to reduce costs. It was necessary to introduce cost cutting measures at short notice. Amongst other things these measures included a significant reduction in staffing at the power plants. The resulting challenges to the remaining power plant personnel must be supported by a high-quality training, further education and qualification concept. Such a concept must also allow the operators sufficient flexibility to accommodate new EU laws.

Ultra Supercritical Pulverised Fuel Combustion versus Ultra Supercritical Circulating Fluidised Bed Combustion: Ultra Supercritical Circulating Fluidised Bed Combustion Comes out on Top?

Frans van Dijen, Patrick Savat, Johan Vanormelingen and Ir. Herman Sablon

The advantages and disadvantages of USC CFBC and USC PFC were compared. The potential disadvantages of USC CFBC are easily counteracted. An advantage of USC CFBC is the high fuel flexibility, although this is less than anticipated and usually limited by the specification of a project. The fuel flexibility of CFBC allows for (co-)combustion of pet cokes and suitable biomass like (dry) wood. PFC may follow grate firing and slag tap furnaces on the path of history.

Pulverized Coal Firing System for the Operation of Steam Generators with low Excess Air

Alfred Gwosdz, Alfons Leisse and Hans-Joachim Quenders

Service life and economic efficiency of steam generators are decisive factors for the operation of coal-fired power stations. Furnace systems can also make a major contribution towards improving the efficiency - for example, by lowering the excess air to values of 10 to 15%. New calculation methods and the numerical simulation offer the chance of analyzing the risk potential early in the planning stage and to introduce suitable measures for a reduction of negative effects.

Benchmarking Energy Efficiency Of Power Plants Using Operational Efficiencies

Jan van der Marel and Ingrid Bins

In 1999 the Dutch government and energy intensive industry agreed upon a covenant on energy efficiency as part of the Dutch climate change policy and Kyoto objectives. In this covenant the industry committed to 'world class performance on energy efficiency', at latest in 2012. In the benchmarking process the industry is obligated to hire an independent third party consultant every four years to define 'world class performance on energy efficiency', further referred to as 'World's Top' (WT), and the distance from the world's top for their installations. The results of the benchmarking have been used in the allocation process of CO2 emission allowances under the EU emission trading scheme (ETS) as a reward for early action.

The Use of Industrial Power Tubes in Recuperative Heat Exchangers

Udo Hellwig, Harald Horn , Axel Kölling and Jürgen Peterseim

Ongoing technological optimisation is a key competition factor, and the energy sector is also responding by seeking to enhance boiler and plant efficiency. It makes sense to recover heat from flue gas at the cold end of the boiler wherever possible, and this can easily be achieved by using air preheaters. The heat recovered from flue gases is then fed back into the boiler or used to dry fuel, resulting in greater thermal efficiency. Innovative solutions have benn developed.

VGB Data Base Generator Damage Cases

Ralf Bomba, Ulrich Groß and Jörg Kaiser

The generator being the main component in the power plant that generates electricity requires maximum reliability and availability. A significant increase in failures raises the question for the cause. The VGB Data Base “Generator Damage“ and the responsible VGB Project Group “Generators“ are a valuable contribution for answering the questions. On the basis of statistical analyses and deliberate assessments by the project group, weak points can be identified and can be discussed with the manufacturers. Besides, the operators can look up events in the data base and can exchange experience with other experts.

Copyright and Protection of Industrial Property for Utilities

Nicole Denise Rademacher

Copyright is increasing in importance in energy services: the companies´ homepage, user manuals, staff inventions, technical databases. Some prominent aspects will be explained for practitioners: Utilities that draft technical instructions and computer programs for special needs are originators in the sense of the German law on copyright. Written elaborations like text elements on web sides, e-mails and contributions in bulletin boards and news groups are of particular importance.