Abstracts - VGB PowerTech Journal 9/2008

Summary Report on the Activities of VGB PowerTech e.V. 2007/2008

Karl A. Theis

VGB PowerTech e. V. (VGB) is the European technical association for heat and power generation. The work of the VGB largely depends on the many backers and employees in the companies and office who, for example, manage and support the activities of the committees. Here detailed topics, e.g. fire safety, damage statistics and draft directives, are handled systematically and consistently, taken up and further developed. The VGB is also involved in power plant research via its research foundation and promotes important topics with funds from its member companies. In addition to this work, the VGB organises seminars, symposia, conferences and the annual “Power Plants” congress. These conferences are further platforms for the international exchange of experience - as is this journal.

New Training Simulators of State-of-the-art Coal fired Power Plants at KRAFTWERKSSCHULE E.V.

Martin Kröck, Klaus Fehse and Heinrich Nacke

For more than 20 years, KRAFTWERKSSCHULE E.V. (KWS – PowerTech Training Center) operates training simulators for fossil-fired power plants at its Essen headquarters. In the course of the construction of the new 800 MW and 1100 MW high-efficiency power plants with hypercritical steam generators, a growing demand for – even multilingual – training of operator personnel from such plants at simulators is arising. Thus, new training simulators are being erected.

Energy from Wind – Perspectives and Research Needs

Hermann-Josef Wagner and Alexa Epe

Wind energy will provide a major share of our future energy supply with the possibility of going offshore. Much research is still required to use wind energy in a reliable way. One of these fields is the evaluation of wind energy in terms of sustainability. The results of Life Cycle Assessments (LCA) show that wind energy converters have a short energy payback time and low emissions, even in comparison with other renewable energy systems. Another field of research is the creation of optimisation models which can provide answers to questions concerning future power generation mix.

Energy from Conventional and Renewable Sources – The Power Supply of the Future

Wolfgang Schröppel

Three approaches for the future energy mix in Germany are presented. It is very clear that renewable energies will take an important part in the future electricity generation. Besides, the use of nuclear energy must be discussed again in our country considering it as possible contribution to solve the CO2 problem. In the long run oil and gas will definitely run out and will therefore play no considerable part in the power supply of the next centuries. There will be no easy way to solve our energy problems. We have to make compromises to find possible solutions.

Availability Optimisation of Wind Power Plants – First Results of the Joint Project –

Harald Jung and Klaus Pfeiffer

The article presents first results of a joint project sponsored by the Federal Environment Ministry of Germany, short name EVW. General objectives of the project are the improvement of systems availability as well as the reduction of costs particularly for unplanned maintenance measurements. Methodologically the effort focuses on a reliability-centred optimisation of work-flow and maintenance processes. The project partners can profit from knowledge gained within other industries. The availability could be increased and costs reduced up to 10% by using modern RAMS and LCC techniques.

Onshore and Offshore Wind Power Plants – Requirements from the Operator's Point of View

Axel Ringhandt, Peter Steinfeld, Walter Sucrow and Ulrich Langnickel

By 2020 the share of renewable energy sources in the total power consumption within the European Union is to amount to 20%. In order to be able to reach the objectives of the European Commission it is required to “professionalise” the operation of wind power plants and to adapt it to the specifications which have proven themselves in the sector of conventional power plants. The international members of the “Wind Energy” Working Group of VGB PowerTech e.V. have formulated the requirements from the plant operator's point of view and have already developed corresponding measures for their implementation.

The Mark-E Strategy for Climate Protection

Arndt Bohrer and Hans-Uwe Schöpp

Electric utilities face a particular challenge in the context of climate protection. Mark-E is aware of its responsibility. Thus, Mark-E accepts this challenge and plans to reduce the CO2 emissions per kWh in its power generation network by 30 % in 2008 compared to the year 2000. In addition Mark-E is engaged in testing and applying innovative technologies.

Appraisal of Revision Cycles for Pump Storage Plants under Modified Operational Conditions

Kurt Klein, Peter Nowicki, Frank Pöhler and Joachim Klein

Over the last decade, for competitive reasons, efforts were made for pump storage plants – as have been made for other generation units – to prolong inspection cycles. During the same period numerous installations experienced significant changes in operational mode compared to the decades before. These modified operational conditions cause increased stress and wear to key components, which stands in contradiction to the aim of prolonging revision cycles. For the further optimisation of maintenance strategies, the VGB Technical Committee “Hydro Power” developed a tool for estimating lifetime consumption at modified operating conditions.

Grid Usage Fee for Pumped-storage Power Plants

Harald Krebs and Dirk Ermlich

The German Regulation Authority (BNetzA) imposed an obligation on grid operators to charge grid usage fees on pumping electricity from January 2008. The consequences are outlined. It is demonstrated that there are good reasons to stick to hat original free-of-charge situation as had been successfully practised in Germany and abroad for many years.

Modern Non-destructive Methods for Examining Turbine Blades and Blade Roots in Steam Turbine Service

Hans Rauschenbach, Michael Siegel and Laurent Capponi

During planned inspections, highly-stressed components of turbine sets are subjected to non-destructive testing in order to identify possible damage before the complete component will fail. The paper presents examples on non-destructive testing at turbine rotor and rotor fittings that have been developed by Siemens Energy and have already introduced in turbine service.

Perpectives of the German Lignite Industry 2008

Matthias Hartung

In 2007 the German lignite companies were economically successfully and at the same time set the course for their future development. Production was on a high level with some 180 million tonnes of coal that were mined. About 12.5 million tonnes of raw lignite were applied in lignite processing. Lignite application in electricity generation was again the most important market with some 93 % and with a total share of 25 %, lignite was the most important fossil source of energy in German electricity generation. The power plants under construction, e.g. in the Rhenish area, i.e. the BoA 2/3 units and the development of new technologies, demonstrate that the lignite industry is heading for the future through investments and R&D activities.

Review of Impacts Affecting Eskom due to Loss of I&C Know-how, Engineering Capacity and Vendor Constraints

John Viljoen and Jacobus Johannes Veldman

Over the last few years, Eskom has experienced a significant turnover of staff leading to an extreme skill shortage. In an attempt to counteract these threats, Eskom has been developing a number of strategies, targeting the various issues. These include adopting a more standardised approach, the use of more stringent policies and procedures, introducing knowledge management principles, providing a centralised oversight function, and implementing advanced information management solutions. This paper will discuss some of Eskom’s recent experiences, as well as some of the proposed strategies to deal with them.

Infrared Furnace Cameras for Detection of Slag Deposits at Furnace Walls and for Lifetime Monitoring of Membrane Walls (Creep Strength)

Ralf Koschack, Norbert Paßmann, Roland Imhof, Bernhard Hoffmann, Günter Hoven and Jürgen Grabig

Infrared furnace cameras are used to take thermal images of furnace walls of boilers fired with pulverisd coal. The thermal image clearly identifies fouling on heating surfaces due to the increased surface temperature thus enabling deliberate cleaning. Infrared furnace cameras are also used in plants with supercritical steam parameters that are currently constructed where the first superheater stage is made of membrane walls.

Oxidation of Steels and Coatings during Exposure in a Bypass of a Steam Power Plant at 608 – 637°C: Correction and Investigations of the Morphology of the Layers

Reinhard Knödler, Stefan Straub and Brendon Scarlin

Within the German research programme KOMET 650, materials for steam turbines were exposed in a bypass in the Westfalen power plant at temperatures between 605 and 637°C. After an operation time of 21700 h (full load) the material samples were removed and the respective oxide scales were analysed in detail by applying scanning electron microscope techniques. In a former publication by the authors (VGB PowerTech 88/3 (2008) it was written erroneously that the 9 % steels cannot be applied in the temperature range > 600 °C. These statements refer only to the application as turbine blades.

(Printed in German. English paper available.)