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29. Meeting in ArnhemAgenda Welcome (Mr. Wels) Plant ageing and maintenance expenditure
Maintenance Quality
Maintenance Organisations
Miscellaneous
TOP 1: R&D at Dutch Utilities (Dr. Nanno Bolt, KEMA) Introduction of KEMA Our business; Serving the electric power marketplace
Profile
Changing market conditions
R&D Playing field
Drivers for electricity R&D Drivers for electricity related R&D are:
Theresponsibilities between the key players in the Electricity SupplyIndustry, the manufacturers, the industry itself and the governmentsare shifting. And so does the R&D focus. What is the impact ofenergy policy changes, of environmental challenges, of competitivemarkets and of new entrants on the R&D needs in the EU-25? And howto respond to unbundling, to the increasing pan-European integrationand to the growing importance of customer demands? The future energy systems: Importantfactors in shaping the future energy system are demographics,urbanization, incomes, energy demand and market liberalization. Threefactors however will have the potential to introduce fundamentalchanges in the energy system. The availability of energy resources -the scarcity of oil in the 2025-2050 period followed by gas - willtransform the energy system. The second driving force is newtechnology: solar photovoltaic - offering widely distributed energy -and hydrogen fuel cells - offering high performance and clean energyfrom a variety of resources - are potentially disruptive energytechnologies. The third key driver is social and personal priorities.Will the changes be pushed by governments on behalf of citizensconcerned about security of supply and environmental impact? Or willthey be pulled by consumer demands for flexible, convenient and cleanenergy services? Two scenarios arise from those drivers; the Dynamicsas Usual scenario and the Spirit of the Coming Age scenario. Lookingback from 2050, the energy transition within the Dynamics as Usualscenario is a continuation of past dynamics.
Fig. 1: The Dynamics as Usual and the Spirit of the Age scenarios The requiremnets of the future consumer Thegrowing importance of the Digital Society will have a major impact onthe demand for electrical energy and requires high reliability andpower quality from the energy suppliers. Differentiation in reliabilitybetween various end users will occur. Premium Power Parks with extremehigh reliability and power quality are realistic concepts. In Fig. 8the reliability demand for various end users is shown, differentiatedin numbers of nines (f. i. 4 nines means 99,99 of the time the supplyis reliable or the annual outage is 52 minutes).
Fig. 2: Reliability differentiation in various service areas Present-dayconsumers however are confronted with power outages having increasinglyimpact on entire societies. Like the major outages in Italy, US/Canada,UK and Sweden in 2003. These events promote in fact - together with theincreased competition between the suppliers - the growth ofdecentralised power generation. R&D playing field Thelevel of market opening and of legal, political and social constraintsvaries from country to country. At one side the European ESI has torespond to the liberalisation of the market, with unbundling, morecompetition and new entrants. On the other side the European ESI has todeal with the requirements for Renewable Energy Sources, therequirements for the environment (and Kyoto agreements) and for thesecurity of supply. R&D Challenges Theobjectives of R&D within the ESI are rapidly shifting from -classic - cost reduction projects to development of customer servicesand business opportunities. Focus is more and more on improving thecompetitiveness of the enterprise among others by development of assetmanagement tools in the changing market. The position of R&D isshifting as well: for product development the manufacturer is seen asthe first responsible. The basic research is performed at universitiesand research centers. The R&D tasks for f.i.a grid company arerestricted to:
The contours of the funding for the future electricity R&D are becoming sharper:
KEMA'S multi-client contract research: TSA Power Generation The Technical Service Agreement Power Generation is:
In 2004 the TSA participants are: DELTA, EdeA,Electrabel, EON Benelux, Essent, EPZ, Nuon. The TSA is open forinternational power generators: EDF participates on product level. Examples of on-going projects on plant-life Forextension of periods between overhauls, for increased reliability andfor addressing questions from the trade departments, inspection toolswhich can be used during operation raise increasing interest. TSAdevelopments introduced or in development are the following:
TOP 2: Life Extension Costs (Henk Wels, NRG) Inthe Netherlands, a large number of power plants are present that couldbe candidates for life extension. The situation is similar in otherEuropean countries. During the April 2004 PGMON meeting, it was notedthat by gathering major cost items, it would be possible to arrive at ayardstick for preliminary cost assessments. Therefore a spreadsheet wasdesigned for input purposes. Power plants were subdivided into systemsusing KKS-coding. For a limited number of projects within PGMONexperience, costs per subsystem were gathered and statisticallyanalyzed. If was found that differences became smaller when resultswere summarized to boiler, turbine, etc. The remaining spread isexplained by problems existing / anticipated in plants, by maintenancebudget in the past and by size and fuel characteristics. The data showthat improvement of boiler forced outage rate is good value for money,the condition of electrical equipment with regard to remaining lifeoften is not precisely known. Finally, old generators should not betrusted. From the subsequent discussion, it followed that assessingHigh Impact Low Probability HILP items is important. This might be asimportant in a Life Extension project, say for the next 15 years, ashaving the every day boiler problems solved. A new DCS might be anexpensive item but worth analyzing. It was concluded that more datawere needed to arrive at a yardstick. Since these data are scarce andconfidential, an approach using technical life extension data incombination with sound cost engineering later on could be analternative. TOP 3: IEC 61508, New standard for safety related Plant Protection System (Paul Thame, E.ON UK)
StandardIEC 61508 (Functional safety of programmable electrical/ electronic/programmable electronic safety-related systems) is now being adopted inthe UK. The UK Health and Safety Executive has endorsed the newstandard as best practice for the design and through-life management ofactive plant safety systems. The objective of the standard is to ensurethat the hazards (personal safety risks) of a plant system are knownand that safety systems are designed to reduce the risk of each hazardto a defined tolerable level. Details of the standard can be found at www.iec.ch/zone/fsafety/fsafety_entry.htm. If the risk is above thetolerable limit, a safety system must be designed that providessufficient protection to reduce the risk to a tolerable level. Theamount of risk reduction required defines a Safety Integrity Level(SIL) for the safety system. Four levels of SIL are defined in thestandard, SIL 1 being the minimum level of protection and SIL 4 beingthe maximum. To illustrate, for a safety system that is not demandedvery often, a SIL 1 safety system must protect people with a failurerate in the range 0.01 to 0.1 per occurrence of the hazard. The SILvalue then determines the hardware selection, design configuration andsoftware development procedures to ensure a system that achievesadequate risk reduction. For higher SIL systems, redundancy anddiversity may be required. Maintenance procedures (e.g. functional testintervals) must then ensure that the system continues to provide therequired risk reduction in service. Each safety system must be given aSIL rating according to the risk that it protects against. Thesafety systems addressed by IEC 61508 are not just Programmable LogicControllers (PLCs). The instruments, signals, actuators and controldevices, as well as any human interface, must all be included in SILassessments as part of the active safety system. TOP 4: Designing and Commissioning DCS in Portuguese Power Plants (Antonio Gonçalves, EDP) NewDCS - Distributed Control System - displaying some important featuresto improve control in Power Plants are available in the market.Obviously, as new facilities in new DCS increase, the efforts to usethem adequately also increase. This effort is substantially reducedbecause, at the same time, modern DCS are associated with InformationSystems, where it is possible to store and manipulate every relevantdynamic data concerning process and controllers. Such data can feed newsoftware to support controllers tuning, thus opening new possibilitiesto obtain remarkably better performances reducing time and manpower aswell. This paper is an approach to the application of new DCSfacilities in Portuguese Power Plants.The applicability of each newpossibility on the control loops of Power Plants is first analysed, itseffects on the concerned dynamic behaviour are identified and someexperimental results are presented. Then the impact of such behaviouron the reliability and efficiency of Power Plant Units and on theenvironment is assessed. Following, some comments about design andcommissioning phases are addressed. The urge to a better specialisationand knowledge of control theory by the commissioning teams of new DCSis also referred. Finally, the consequences of the replacement of theold control systems and control rooms by the new DCS in Power Plants infunction for a long time will be discussed. This discussion alsoanalyses the effort that must be made by operating teams to adapt tothis new operating philosophy and the subsequent urge to training allthe staff dealing with such devices. TOP 5: Cost Saving by Ultrasound Regeneration of Denox Catalysts (Dr. Alexander Schluttig, Envica Kat) Deactivation of DeNOx - Catalysts Eventough the catalyst is not consumed during the reaction, it graduallydeactivates due do the exposure of so called "catalyst poisons"contained in the flue gas. Such deactivation of SCR catalyst is causedby arsenic, potassium, phosphorus and other elements contains in theflue gas as well as physical surface layers formed by fly ash and/orreaction products such as gypsum or even eutectics.Until recently, thedeactivation of the catalyst eventually required the very costlyreplacement of the used catalyst with new catalyst as soon as theoverall activity became insufficient. In addition to the high expenseassociated with replacing the catalyst, this method also led to thedisposal of the considerable amount of residual activity remaining inthe catalyst. Catalyst Regeneration instead of replacement Traditionally,partially deactivated catalyst needed to be replaced with new catalyst.In almost all cases, this costly replacement can be avoided by usingour highly efficient catalyst regeneration process. Ultrasoundregeneration is based on a combination of washing, ultrasonic cleaningand chemical reactivation of deactivated SCR catalyst. Ultrasound regeneration: deep cleaning as perfect as possible
Ourproprietary patented SCR catalyst regeneration process allowssuccessful regeneration of even the most poisoned catalyst and theremoval of even the most persisting blinding surface layers. All thesedeactivation causes are effectively removed without impacting thecatalytically characteristics and structural integrity of the catalystmaterial. Generally 95 - 100 % of all kinds of fly ash are removed without any influence to the mechanical strength of the catalyst.
Fig. 1: Catalysts of different types before and after regeneration Wefind fly ash blockings in many different forms up to the blockage by aso-called popcorn ash and to concrete-like plug-ins. The ENVICA Katultrasound regeneration is able to remove these extreme blockagesalmost completely without influence in the mechanical strength of thecatalyst. Activity (k) The activity (k)is the measure for the transferring speed of ammonia and nitric oxidesto molecular nitrogen and water at the catalyst. It is indicated inm/h. The higher the activity, the better is (more active) the catalyst.The activity decreases because catalyst poisons and fly-ash aredeposited at the catalyst in the course of the DeNOx - business. Assoon as the compliance with the NOx-limits isn’t ensured any more,measures must be taken. By ENVICA Kat regeneration 90 - 100 % of the new catalyst activity is restored In some cases an activity (k) above the original one (k0) is possible.
Fig. 2: Activity (k) in comparison to the factory new activity (k0) before and after regeneration (samples) SO2/SO3 Conversion rate Theoxidation of sulphur dioxide to sulphur trioxide at the catalyst is amostly unwanted competitive reaction to the activity since sulphurtrioxide combines with water to sulphuric acid. The SO2/SO3 conversionrate (measured in %) says how much SO2 is changed to SO3. The lower theconversion rate, the better is the catalyst. Both the production of newcatalysts as well as the regeneration always has to find a compromisebetween an activity as high as possible and an acceptable SO2/SO3conversion rate. Besides a decrease of activity the catalyst operationcan lead to an increase of the conversion rate. In such cases only theENVICA Kat process can achieve a reducing of the SO2/SO3 -conversion-rate to the value of the factory new catalyst. Thus withouthaving losses in the activity after the regeneration. Bysimple washing with water or deionised water the conversion rate willbe increased considerably. By the development of a special methodENVICA Kat has managed to reduce the conversion rate to the level of afactory new catalyst. Deactivation of regenerated catalysts Theexperience of our customers prove the same deactivation rate ofultrasound - regenerated catalysts as new ones under the same firingconditions as before regeneration.
Fig. 3: Disassembly after 35.000 operating hours and further operation with ultrasound regenerated catalysts Anultrasound - regenerated catalyst is as good as new. The lifetime canbe doubled and more. Mostly catalysts are regenerative several times.We have experience with the 3rd regeneration of the same catalyst. Thecosts for regeneration are approx. 50% of new material. TOP 6: RIMAP - Risk Based Inspection and Maintenance Procedures (Dr. Jörg Bareiss, EnBW) Riskbased Inspection and Maintenance Procedures for European industry(RIMAP) is an EU funded initiative (budget: 3.6 mill EURO; EU: 1.7millEURO; duration march 2001 to march 2005). RIMAP consists of 3projects: a research and technological development project (RTD), ademonstration project (DEMO) and a Thematic Network (TN). The objectiveof the RIMAP RTD project is to define a unified approach to making riskbased decisions, within the field of inspection and maintenance. Riskis here understood as the combined effect of probability of failure andthe consequence of a failure (personnel safety, quality of produce,environmental damage and economic loss). The RIMAP DEMO projectconsists of four demonstration cases, one for each of the involvedindustry sectors: petrochemical, power, steel, and chemical industry.The techniques can easily be extended to other industry sectors. TheRIMAP TN accompanies the RTD and DEMO projects by disseminating theinformation, and results of the RTD and DEMO part to a wider communityof companies that review results and generate an overall industryacceptance. Public project results will be disseminated through the RIMAP web site (http://research.dnv.com/rimap) and via the RIMAP Thematic network (see http://www.mpa-lifetech.de/rimap). Theapplicability and usefulness of RIMAP methodology were demonstrated onseveral practical cases on power plants (i.e. boiler parts, turbinecomponents, piping). The application with emphasis on high-temperaturesystems (main steam/hot reheat line, boiler parts) using ALIAS SoftwareSystem was shown by Mr. Bareiss, EnBW (see "Rimap BalticaVIBar040608-2.pdf"). Since creep and fatigue are main damage mechanisms,the PoF determination in this example is based on creep exhaustion andfatigue exhaustion. It is assumed that average creep rupture strengthand fatigue strength have a log-normal distribution. The determinationof consequences of failures was considered from economical aspects(i.e. repair/replacement costs, lost production time). The riskanalysis was performed for different levels, starting with thescreening level and generic data and ending for critical componentswith a detailed analysis (i.e. high-temperature fracture mechanicsanalysis) with all obtainable data for the component. Based on actionsfor different risk areas in the user defined risk map, inspection andmaintenance (I&M) activities/levels were assigned. The optimizationprocess includes comparison of value at risk before and after applyingthe I&M actions suggested in the I&M plan. Cost savings areconsidered by eliminating ineffective inspection, extending inspectionintervals and greater plant availability. Additional expected benefitsare improvement to the plant safety and reliability. TOP 7: Maintenance Standards (Antoine Despujols, EDF) Nowadaysdifferent organizations for standardisation are providing standards inthe maintenance area. Respectively at international and Europeanlevels, the Technical Committees TC56 (Dependability) of InternationalElectrotechnical Commission (IEC) and TC319 (Maintenance) of EuropeanCommittee for Standardisation (CEN) are carrying out documents whichare generally included in the set of national standards of each membercountries. Some works done by working groups of these TechnicalCommittees deserve to be mentioned: IEC/TC56/WG1 is working onterminology and is revising the IEV 50(191) which defines dependabilityterms including a number of maintenance terms. IEC/TC56/WG3working on dependability management provided interesting applicationguides about Maintainability (IEC60300-3-10), Reliability CentredMaintenance (IEC60300-3-11), Integrated Logistic Support(IEC60300-3-12), as well as a general presentation of "Maintenance andmaintenance support (IEC60300-3-14)". Some new work items should beproposed on spare parts management, maintenance support planning, andmeasurement of maintenance performance. CEN/TC319/WG3 wrote a "guideline on preparation of maintenance contracts (ENV 13269)". CEN/TC319/WG4wrote in 3 languages (English, French and German) a "Maintenanceterminology" standard which contains about 120 basic term definitions.
Otherstandards can also be mentioned as "a guide to Reliability CenteredMaintenance (SAE JA1012)" produced by the Society of AutomotiveEngineers or "documents for maintenance (EN13460)" produced by CEN, aswell as the present CEN/TC319/WG6 work about "Maintenance KeyPerformance Indicators". These documents, which are the result of largediscussions and comments, can be useful for maintenance people. Inthe liberalised energy market the evaluation of the capacity of an ownpower plant compared to other power plants (benchmarking) is of greatimportance. Strategic tools to optimize the capacity of a power plantin competition are:
Thepower plant information system KISSY of VGB is the tool, which treatsthese questions efficiently. It currently contains availability dataand performance indicators from over 9,760 plant years of German andforeign power plants. The elaborated performance indicators are definedand analysed in the VGB Guideline "Availability of thermal power plants- basis and compilation" (VGB RV 808 in German language only). Thenew kind of operating power plants caused by the liberalised marketrequires the consideration of further performance indicators. KISSYenables to extend the field of performance indicators substantially.The intended extension will comprise:
Thedata base system KISSY enables the online input of data via Internet byauthorised persons. Standardised reports about the evaluation ofperformance indicators and analysis of non-availability of power plantcomponents in ten year periods are available at VGB PowerTech Services.Special evaluations will be provided on demand at individual costs. TOP 9: Risk of Gas Explosions in Power Stations (Erwin van Wonderen) Inthe presentation Quantitative Risk Assessment (QRA) is presented andapplied to hazards of gas lines in an urban environment. In theNetherlands a risk policy was devised starting in the early 70’s mainlyto investigate the acceptability of risks posed by the 2 Dutch Nuclearpower plants. At the moment that the European guidelines andlegislation came into play (European "Seveso-II" guidelines), this wasintegrated with the risk policy. Part of the regulations is the need ofa Safety report. The safety report is obliged if the quantities offlammable, toxic or explosive substances surpass a certain amount,using a selection method. Part of the safety report is the QuantitativeRisk Assessment (QRA). In the QRA a systematic probabilistic assessmentis made of initiating events (Los of containment events), outflowmodelling, possible physical consequences (effects like blasts, jetfire, toxic cloud dispersion) using event trees and meteorology andresulting risk to humans (probability of death as a result of heatradiation, pressure wave effects or intoxication using probitfunctions). The end result is two graphs, the individual risk and thegroup risk plot. At present the individual risk should not surpass thelevel of 10-6/year outside the fence and the group risk should notexceed the limit line 10-3xN-2/year, where N (number of victims)>10. During the 80-ies a committee was established (backed byvarious governmental ministries) called "the committee on theprevention of disasters", in which various scientific organizationswere gathered. The committee produced a number of guidelines called"the colored books"*. These books provide detailed practical models andknowledge on all afore mentioned topics. Power stations areobliged to author the Safety report if for example tanks with ammoniaare present (toxic hazard). Interestingly, the risks of natural gaspipe lines present at power stations need normally not to be evaluated.As shown in the presentation, due to the proximity of urban areas tosome Dutch power stations, failure of gas pipe work inside the largevolumes of the buildings pose an explosion thread, while piping outsidethe building can lead to explosions and heat radiation (as seen in theaccident in Ghislenghien, Belgium). As in some cases the group-riskexceeded the limit, fast shutting gas valves (which will close at afull bore rupture) will be applied, lowering the risk to acceptablelevels. *:
To be obtained at "Sdu Uitgevers", The Hague (www.sdu.nl). TOP 10: Technical Management Strategy in ESB Power Generation (Richard Sheehan) Introduction Aprevious PGMON presentation (Paris, meeting no. 27), the technicalchallenges facing ESB were outlined. This presentation was to give animpression of some of the technical initiatives which have since beenundertaken, which are designed to manage the various challenges. Challenges Some of the technical challenges facing ESB include:
Current Strategy
Thecurrent strategy is made up of a diverse number of technicalinitiatives, covering safety, plant and environmental risk areas.However there is not always clear definition as to how theseinitiatives fit together, or a systematic way to demonstrate that theapproach is comprehensive.
Aframework was designed to provide a structured and systematic mannerfor managing technical issues. Such an approach will help ESB to complywith safety and environmental obligations and as well as compliancewith corporate governance requirements. Amodel was designed which would incorporate existing Standards,Guidelines and Local Procedures that are currently being implemented inESB. The model required however a high level Technical Strategy andhigh level Technical Policies to be put in place.
Typical Policy Anexample of a typical policy was described (Integrity Policy), which setout high level aspirations in areas such as life assessment,documentation control, technical competencies, condition monitoring etc. Cross Reference with Standards & Guidelines Animmediate application of the framework was to examine the adequacy ofthe current body of Standards and Guidelines. An assessment of thecurrent suite of Standards and Guidelines and cross reference with thestated policies allowed a number of areas tobe identified where thereare gaps or inadequate levels of supporting documentation. Cross Reference with 7-Year Plans ESBstations are currently involved in detailing technical initiatives tobe undertaken over the course of the next 7 years in order to returnthe plants to conditions that will allow them to achieve performancetargets. The template being used in stations allow them to link alltechnical initiatives with the technical policy areas within theTechnical Management Framework. Technical Initiatives Anumber of technical initiatives have been developed or are on-going,which link to the Technical Management Framework. These include
TOP 11: Modification on EDF Organisation (Claude Degrave, EDF) Sincethe 90's, the EDF Group has made determined and sustained efforts tomeet the challenge of rapidly changing and growing competition in theenergy field. Deregulation, concentration in the energy sector, andtechnological evolutions has created new risks and great opportunities.EDF consequently internationalised its activities and expanded intomulti-service and multi-energy activities. As of February 1st, 2002,the Group will be implementing the new management structure. It will beorganized around Branches, Divisions and Business Networks. TheBranches will be the operational arms of the Group, acting as resourcedevelopers and market actors under the overall strategic guidance ofthe Executive Committee. The Business Networks will ensure that EDF'sskills and businesses evolve consistently and in synergy. The ExecutiveCommittee will concentrate on strategic planning and investmentdecisions, definition, implementation and control of overallobjectives, and related tasks of risk management and optimization ofGroup activity. The new Law of August 9, 2004 induces some impact on EDF:
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