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Renewable Energy 67 (2014) 143e152

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Renewable Energy

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Sustainable asset integrity management: Strategic imperativesfor economic renewable energy generation

Chinedu I. Ossai, Brian Boswell*, Ian J. DaviesDepartment of Mechanical Engineering, Curtin University, GPO Box U1987, Perth, WA 6845, Australia

a r t i c l e i n f o

Article history:Received 6 October 2013Accepted 14 November 2013Available online 27 November 2013

Keywords:SustainabilityRenewable energyAsset integrity managementAsset performanceEnvironmental conservationDowntime minimization

* Corresponding author. Tel.: þ61 8 9266 3803.E-mail addresses: ossaic@gmail.com (C.I. Oss

(B. Boswell).

0960-1481/$ e see front matter � 2013 Elsevier Ltd.http://dx.doi.org/10.1016/j.renene.2013.11.024

a b s t r a c t

This paper develops a framework for sustainable asset integrity management (AIM) with regards torenewable energy generation plants. The authors conclude that increased downtime, low energy output,high cost of maintenance and repair operations, which are attributable to poor assets integrity man-agement, can be mitigated with sustainable AIM. The enhancement of economic and efficient energygeneration in renewable energy plants, therefore, involves a structured procedure that combines socio-economic and environmental demands in decision supports for facilities management. This can beachieved utilizing a function interfaced organizational model and techniques that include mitigation,prevention and regulatory programmes. Environmental conscious planning, review and task execution inAIM are vital to health, safety and environmental conservation whilst improved asset lifecycle perfor-mance can be reached through competence, compliance, control, communication and co-operation ofmanagement and personnel. In conclusion, proper coordination of AIM through an accurate under-standing of the stakeholder demands results in efficient renewable energy generation.

� 2013 Elsevier Ltd. All rights reserved.

1. Introduction

The need for a greenworld economy has been the focus of manyresearchers worldwide with the United Nations EnvironmentalProgramme (UNEP) defining a green economy as one that results inimproved human wellbeing and social equity, while significantlyreducing environmental risk and ecological scarcities [1]. This im-plies that theworld energy consumption can be greenprovided thatenvironmental considerations accompany their utilization. Thisscenario is unfortunately not the casewith fossil fuel which is one ofthe world’s predominate energy source. The extent of greenhousegas (GHS) emission by fossil fuel is so significant that there is anurgent need for reducing the carbon footprint of theworld via use ofalternative energy sources that are benign to the environment. Thishas led to more interest in renewable energy sources (RES) whichhave a lower pollution effect when compared to fossil fuel. Researchshows that the world’s energy need will grow from 12,271 millionton oil equivalent (Mtoe) in 2008 to 18,048 Mtoe in 2035 with anaverage annual increase of between 1.4% and 3.4% for non-OECDcountries and approximately 0.3% for OECD countries [2]. Consid-ering the fact that 81% of the total energy consumed in the world in

ai), b.boswell@curtin.edu.au

All rights reserved.

2009was fromfossil fuel [3], the current implication of higherworldenergy demand would be increased pollution together with theassociated complexities of fossil fuel utilization [2] shouldRESnot beutilized to bridge the gap.

Themajor challenges ofworld energy at the present time includeensuring energy security, combating climate change, reducingpollution based risks to public health and addressing energypoverty [2]. To address these problems require a proactive renew-able energy development and utilization policy which according tothe Green Energy Report (GER) model will involve a 40 year globalinvestment of $650 billion annually in order to provide a 27%renewable energy supply by 2050 whilst reducing greenhouse gasemissions by 60% [4].

According to a report by Bloomberg New Energy Finance andUNEP, the investment on renewable energy assets around theworldgrew from $33 billion in 2004 to $211 billion in 2010 [5] as shown inFig. 1. This continuous investment on generation plants requiresproactive steps to maintain the reliability of the assets and ensureeconomic and efficient energy generation. The aim of this paper isto develop the strategies necessary for managing assets in renew-able energy plants in order to ensure that cost is minimized. Out-lining the possible challenges of different RES and associated assetfailure patterns will also provide experts with more informationconcerning expected impedances to the establishment of renew-able energy plants whilst ensuring asset integrity through mini-mized maintenance costs.

Fig. 1. Global new investment in renewable energy (2004e2010) [5].

C.I. Ossai et al. / Renewable Energy 67 (2014) 143e152144

1.1. Challenges of renewable energy (RE) plant operation

The establishment and operation of RE generation plants are notwithout challenges which may be technical, economic, environ-mental and social in nature. The primary challenge is that the levelof development of technologies for the extraction of the RE shouldnot be comparable to that of fossil fuel hence making the cost ofenergy production unreasonably high [2,6] as shown in Table 1[6,9e11]. For example, this table illustrates the projected futurecost of generating RE to be high in comparison with that of con-ventional fossil energy sources in US, UK and Australia. However,Owen [7] has argued that should the externality costs of fossil fuelbe built into energy generation and tariffs then RE would be moreaffordable than fossil energy. The return on investment is another

Table 1Levelled cost of energy generation for renewable energy compared to other sources[6,9e11].

Plant type Cost for plants entering service in

2017 2015 2015

(2010US$/MWh)

(2010£/MWh)

(2010AUD$/MWh)

USa UKb Australiac

Coal 99.6 80.67e89.65Coal with CCS e 128 135.06e161.53Advanced coal 112.2Advanced coal with CSS 140.7Natural gas (NG) firedNG: conventional combine cycle 68.6 83 93.57NG: conventional combine

cycle with CCS95 149.51

NG: advanced combined cycle 65.5NG: conventional

combustion turbine92.8

NG: advanced conventionalcombustion turbine with CCS

132

Nuclear 112.7 80e105 133.36Geothermal 99.6 105e268 71.14e135.53Biomass 120.2 141e154 99.58Wind 96.8 88e139 87Solar PV 156.9e251 228 208.60e438Hydropower 89.9 59e105 191.81Wave e 227e237 208.07e362.13

CCS: Carbon control and sequestration.a Source: US Energy Information Administration [9].b Source: UK department of Energy and Climate Change [6,10].c Source: CSIRO publication, Unlocking Australia’s Energy Potential, 2011 [11].

major factor influencing investment decisions with Leijon et al. [8]stating that the return on investment for RES should be measuredas the rate of energy production since the energy obtained by mostRES is not stored but instead transmitted immediately e the realreturn on investment should therefore be a measure of the utilityfactor. This outcome of this approach would make the length oftime expected to recoup invested capital on RE generation to belonger for those with lower utility factors.

Operation and management of RE plants can be painstakingdue to complexities of the operation, cost and environmentalconcerns [12,13]. For example, data acquisition and conditionmonitoring can be difficult for plants located offshore andhence data would need to be remotely acquired using theGlobal Positioning System (GPS), satellites and personal com-puters with database systems. Servers may also be deployedfor operational monitoring and evaluation of incoming fielddata [14]. One of the crucial drawbacks in the utilization of REis variation of climatic conditions [12] which makes it imper-ative that optimization models be used for planning energygeneration operations as noted by previous researchers [12,15e17]. Proper planning of inspection and maintenance pro-grammes is also vital in achieving cost savings and efficientenergy generation.

The UNEP (2011) report on renewable energy [2] indicated thatthe cost of RE was becoming increasingly competitive with fossilfuel due to increased research and development (R&D), economiesof scale, learning effects through cumulative deployment andincreased competition among suppliers e however, further gov-ernment policy support and implementation was deemed vital.According to Wood and Dow [18], deficiencies in the imple-mentation of renewable energy policy in the United Kingdomwereattributed to factors such as: (i) finite and limited duration ofsubsidies lifespan, (ii) excessive focus on competition and low cost,(iii) unresolved planning and grid network issues and (iv) policyuncertainty/excessive charges. Not only limited to the UnitedKingdom, such problems have been among the main difficultiesassociated with effective deployment and use of RES throughoutthe world.

1.2. Geothermal energy

Apart from the cost of generating geothermal energy, waterchemistry management is another major challenge that hasaffected the efficiency of plants around the world [16,19,20] witha summary of different failures encountered in geothermal plantsdue to water chemistry issues being presented in Table 2.

1.3. Wind energy

The generation of RE fromwind energy has become increasinglypopular with approximately 3% of energy worldwide being pro-duced from wind energy during 2012 [21]. Among the imminentchallenges facing wind energy generation is the high cost ofmaintenance and operation together with the low efficiency(typically 25%) of the generating plants [22]. A summary of avail-able data for the downtime accrual and failure rates of differentwind turbine components has been summarized in Fig. 2 [25,27e29]. Whilst the gearbox component in general has traditionallycontributed to the highest downtime [22e24], ageing wind farmshave been particularly susceptible to significant failure rates andreduced power output/efficiency of this component. Indeed,research has indicated that the reliability of gearboxes in windfarms is of major concern and relates to the design andmanufacturing processes amongst other causes. Musial et al. [24]concluded the gearbox reliability problem to be generic with 10%

Table 2Common failure types in geothermal plants, their effect and mitigation strategies.

Type Effects Mitigation RMK

Corrosion - Failure of unprotected components- Leakage of pipes- Collapse of wells/casings- Loss of integrity of components likeheat exchangers, wellhead valves, etc.- Plant shutdown- Wetness loss in system

- Use of corrosion resistant materials- Injection of chemical inhibitors- Coating of materials- Installation of drain catcher

Mineralization of reservoirs results inchange in chemical compositionof geothermal fluid

Erosion - Loss of integrity of pipes- Reduced efficiency of plants andincreased downtime- Moving blades erode due to moisture

- Separation of solid particles from the wells- Use of resistant material- Installation of erosion protection onturbine blades

The extent of fluid material interactiondetermines the degree of impact

Thermalcycling

- Physical damage of gathering system- Loss of integrity of casing andexposed wells- Increase in turbine exhaust pressurewhen non-condensablegas is in the system- Can result in premature well failure

- Temperature of pipe should be maintainedat a steady state- Steam flow in pipe should be maintainedat about 35% of full flow- Installation of non-condensable gasextraction mechanism

Condensation build-up in steam gatheringsystem can cause pipeline and turbine damage.

Scaling - Impede fluid flow and results inpressure drop- Reduce efficiency of the plantand reduce power output- Impair heat transmissionefficiency becauseof silica, CaCO3, etc.,clogging of pipes, turbine nozzles, etc.

1. Chemical treatment- HCl pumped into wells to controlCaCO3 in boreholes- Washing casing with HCl toremove calcite- Washing equipment with ammoniabiflouride to removesilica and NaOH in wells

Proper management of the chemical balancein the well helps to reduce scaling.

2. Cavitation descaling3. Installation of separators4. Washing operation5. Periodic overhauling

Fig. 2. Summary of wind turbine component failure rates [25,27e29]. Note that per-centage values refer to percentage of component failure with respect to totalcomponent failures.

C.I. Ossai et al. / Renewable Energy 67 (2014) 143e152 145

of failures being contributed to manufacturing anomalies withbearings being the major cause of failure. Other researchers such asRibrant et al. and Zappala et al. [25,26] have stated the contributionof gearbox components to failure trends in wind farms to be closer

Table 3Contributions to onshore wind farm downtime [17,30].

Component Contribution to downtime (%)

Insufficient wind 72Grid 21Mechanical 4Preventative maintenance 2Electrical 1

to 20% whereas Herbert et al. [27] concluded that overall me-chanical failure, which included the gearbox, brake pads, hydraulicunit, yaw unit and blades, accounted for 79% of failures in windfarms.

Whilst wind power density (WPD) is a major challenge for on-shore wind farms, harsh environmental conditions hamper reli-ability and safety for the offshore variety [17,30]. Contributions forthe downtime of onshore wind turbines have been shown inTable 3.

1.4. Hydropower energy

Hydropower energy is a mature RE technology that hascontributed significantly to worldwide energy generation. Whilstthe cost of producing this energy in the US during 2011 rankedlowest amongst other energy sources (fossil, nuclear, gas turbine,wind and photovoltaic) [30], major challenges still exist for theoperation of hydropower plants as follows:

� Seasonal water (river) flow and siltation affect/inhibit the eco-nomic viability of the plant [31].

� Difficulty of securing finance and lack of government incentivesfor small hydropower plants.

� Uncertainty in the optimal operation modelling of plants dueto complex and unreliable long term climate and weatherpatterns triggered by global warming [32].

� Environmental problems associated with the building of hy-dropower energy plants include:i. Reservoir impoundmentii. Loss of biodiversityiii. Modification of water qualityiv. Modification of the hydrological regimev. Barrier for fish migration and river navigation [33].

C.I. Ossai et al. / Renewable Energy 67 (2014) 143e152146

1.5. Solar photovoltaic (PV) energy

According to Bahadori and Nwaoha [34], the major challenges ofgenerating PV energy include:

� Deduction in government incentives, falling investment costsand high risk of investment.

� Problems associated with the storage of energy together withthe high technology cost is making large scale commercializa-tion difficult [34].

The efficiency of PV generated energy is affected by the tem-perature of the cells, humidity and dust particles, however, thesystem of feeding generated energy directly to the existing elec-tricity transmission grid results in excess generation of energy atdifferent periods of the year due to the abundance of solar energyat such periods [35,36].

1.6. Biomass energy

Traditional biomass energy sources accounted for 10% of totalenergy consumption worldwide in 2009 with it being the pre-dominate energy source for approximately 2.7 billion peoplefacing energy scarcity [2]. Biomass energy generation has movedfrom the first generation of food crop utilization to the secondgeneration of high reliance on lignocellulosic biomass such asagricultural waste, forest residue and organic waste [37,38]. Theproblems of second generation biomass energy generation areknown to include:

� Immature technology which requires advancements in pre-treatment processes to forestall associated high productioncosts [38,39], there being a need to reduce the energy neededfor feedstock digestion to biofuel by:i. Enhanced feedstock development

Fig. 3. Hierarchy of elements of sustainable a

ii. Improved pre-treatment technologyiii. Reduction in the enzyme production cost and co-

fermentation of glucose and xylose [40].

1.7. Ocean/tidal energy

This energy source is highly predictable when compared withother renewable energy sources [41]. However, similar to mostrenewable energy sources, the technology is not well developedand thus makes commercialization expensive [6]. To connect thisenergy to the grid becomes especially problematic when the gen-eration plant is sited far from the shore.

2. Asset integrity management (AIM) framework forrenewable energy (RE) facilities

The procedure for sustainable asset integrity management(AIM) broadly comprises of three operations, namely, mitigation,control and regulatory programmes as shown in Fig. 3.

2.1. Mitigation programme

2.1.1. Corrosion monitoring and controlThe application of relevant corrosion monitoring and control

measures is necessary for AIM due to the presence of water andoxygen in heat exchangers, cooling towers, pipeworks, etc.,resulting in corrosion. Whilst it may be extremely difficult to stopcorrosion from occurring altogether, however, the primary concernof would be to reduce the impact to an acceptable level. Differentasset corrosion control and mitigation programmes have beensummarized in Table 4.

2.1.2. In-service inspection (ISI)This technique for the estimation of remaining useful life (RUL)

uses non-destructive inspection techniques for asset integrityprediction [42]. ISI has widespread usage in the oil and gas

sset integrity management programme.

Table 4Corrosion control programmes.

S/N MitigationStrategy

Remarks

1 Appropriatematerials

Use of corrosion resistant alloys, non-metallicmaterials like reinforced composites,thermoplastic and polyethylene lined pipelines

2 Chemicaltreatment

Use of corrosion inhibitors, biocides, oxygenscavengers, gas blanketing, vacuum deaerationin pipelines,vessels and wells

3 Coating & lining Organic coating, metallic coating, lining, cladding4 Cathodic

protectionSacrificial anode, impressed current system,hybrid system

5 Process control Identify key parameters: pH, temperature,pressure, flow rate,water chemistry, chloride ion, dissolved metals,bacteria, suspended solid,oxygen and chemical residuals

6 Design detailing Ensure ease of access and replacementi. Install valves that allow for effective isolationof pipeline segmentsfrom the rest of the systemii. Install binds for effective isolation of inactivepipeline segments.

C.I. Ossai et al. / Renewable Energy 67 (2014) 143e152 147

industries with attendant advantages that include risk reductionand cost minimization [43] that may be easily transferred to REplants when utilized for AIM. One point that should be borne inmind is that errors may still be encountered in using ISI for thechecking of asset RUL and determination of asset integrity [44] andhence the need for an integrated approach that will combinedifferent techniques for the prediction of asset integrity.

2.1.3. Risk based inspection (RBI)The overall goal of inspection and maintenance activities on an

asset is to improve the reliability and minimize lifecycle cost. RBI isa cost effective method of managing the integrity of assets throughtarget based inspection programmes and RUL analysis. RBI is asignificantly cost effective procedure in comparison with otherinspection types especially in offshore operations [45,46]. RBI is anoptimization tool for inspection and maintenance which thereforemakes it suitable for the indexing of risk of assets for reliabilityassessment. In order to have an optimization model for inspectionor maintenance, proper data acquisition and pro-active monitoringmethods would be necessary.

2.1.4. Ageing management programme (AMP)AMP is a set of activities designed to determine on-time asset

degradation processes in order to establish proper strategies tomitigate deterioration or else to plan alternative actions to forestallunexpected failure [47,48]. Ageing processes most associated withrotating and static mechanical equipment used in RE plants includewall thinning, corrosion, creep and fatigue failures [49]. Whereasthe ageing process for assets cannot be eliminated due to theinherent physical, chemical, environmental and operational activ-ities of the assets, the impact of the ageing stressors can bemanaged in order to reduce the rate at which ageing occurs.

2.2. Preventive programme

2.2.1. Preventive maintenance (PM)Preventive maintenance is an action taken on a time based

interval (or length of hours of operation) of the asset in order tomitigate against degradation or else to reduce it to an acceptablelevel. PM is a predominant practice in most process industriesdue to the attendant advantages that include increased asset

availability and reduced downtime, improved workplace safetyand better quality products. The great importance of PM inoperation has been reported by numerous findings in the litera-ture. For example, PM optimization through minimal intervals ofmaintenance operation and integrated PM production schedulingdecision processes has brought about significant cost savings andimproved productivity [50].

2.3. Regulatory programme

2.3.1. Condition based maintenance (CBM)CBM is a maintenance approach in which decisions concerning

maintenance are based upon condition monitoring of the equip-ment [51].Whilst this technique is awidespread assetmanagementtool within the oil and gas industries, CBM has not been widelyadopted by other industries due to the associated cost e the reasonwhy some authors have attempted to produce an open system ar-chitecture that would make the technique more widely available tocompanies [52]. The use of CBM in sustainable AIM would likelyresult in advantages that included reduced maintenance and lo-gistic costs, improved asset availability and protection againstfailure of critical mission equipment. Condition monitoring of anyequipment is vital for CBM and modelling acquired data from theequipment can be done using artificial neural networks (ANNs) as alow cost tool for optimization, pattern recognition and prediction[53]. Whilst asset failure patterns may not necessarily be synony-mous with age [25,54], deterioration processes and stochastic in-spection policies may form an optimal cost effective decisionprocess for a CBM model in which the researchers utilize Markovdecision processes. Another work on proportional hazards model-ling was used to identify the risk factors affecting the health of assetmanaged with condition monitoring for optimal CBM decisions[55] with the authors applying economic and other risk factors toproduce the appropriate decision that would best provide for sus-tainable AIM.

2.3.2. Total quality management (TQM)The principle of achieving sustainability in AIM revolves around

quality planning, quality control and quality improvement. In orderto optimize the outcome at all times in the management of assets,there must be a combination of technical and behavioural factors inthe management process. These two aspects of TQM have beendescribed by some experts as the soft and hard TQM with the softTQM comprising mainly of training and education, loyalty, leader-ship, teamwork and empowerment [56]. The synergy betweenthese aspects of TQM is necessary for sustainability of assets whilststriking a balance between the cost of quality management and thecost of failure is necessary to ensure that health, safety and theenvironment are not compromised during production. It is there-fore possible for an organization to achieve quality cost savings andmanage soft and hard TQM improvements should the trade-offbetween quality improvement, cost and customer desires beknown [57].

2.3.3. Feedback mechanismsWhilst the facilities and operators of most assets in renewable

energy plants require licences and/or one form of registration/competency or another, the implementation/enforcement ofthese standards are vital to the sustainability of the assets. Thereview and updating of operator experience through frequenttraining are vital to operational safety. Information flow is anessential tool for AIM hence the inter/intraorganizational cross-breeding of ideas on technical issues is important for decisionmaking e the schematic for the feedback mechanism has beenshown in Fig. 4.

- R & D

- Technical Reports

- Regulatory Agencies

- Contractors

- Other Interest Groups

Design & Manufacture

Plant ManagementAnalysis & Decisions

Operation & Maintenance

Activities

TechnicalStatus of

Plants/Assets

Process Control Standards

AssetConditionReports

Operational & Technical Data

Emerging Technologies

Scope of Work, Objectives & Requirements

Improved Designs & Modifications

Deviation Reports New Technical Developments

Fig. 4. Operational feedback mechanism for sustainable asset integrity management.

C.I. Ossai et al. / Renewable Energy 67 (2014) 143e152148

3. Organizational model for asset integrity management

Maintaining the integrity of assets is a corporate social re-sponsibility [58] which is aimed at balancing the social, eco-nomic and environmental performance indicators. Theorganizational model for sustainable AIM in RE generation aimsto satisfy the stakeholder demands through organizational per-formance goals whilst enhancing the performance indicators.

Fig. 5. Relationship between plant perfo

The interaction of these performance indicators has been pre-sented in Fig. 5.

To satisfy the stakeholder demands understanding of how to:

i. Prevent environmental and social issues whilst remainingeconomically viable in production.

ii. Model, mandate and manage complex supply chain issues aswell as preserve the integrity of the organization and plant.

rmance and stakeholder demands.

Plant & Asset Management- Initiate Sustainable

Asset management Programs

Stakeholders- Regulatory

agencies- Design- R&D - Government - Codes and

Conducts - Manufacturing - Research

Institutes

Sustainabilitymanagement UnitCo-ordinate relevant activities for sustainable assets management

Plant DepartmentsImplement Sustainable Assets Management

- Operations- Maintenance - Technical Support - System Engineering - Quality control - Procurement & Logistics

Environmental & Quality ControlEvaluation and Analysis for sustainability

Contracts Collaborations

Evaluate Standards/KPIs

Evaluate Reports

Document regulation for sustainability standards

SituationReports

Services & standards

Recommend indicators of

sustainability

-Report on Sustainability Indicators - implementation reports

Fig. 6. Organizational model for asset sustainability.

Fig. 7. Sustainable asset integrity management framework context diagram.

C.I. Ossai et al. / Renewable Energy 67 (2014) 143e152 149

Fig. 8. Interaction of asset integrity indicators and plant management team.

Asset Performance

Economic KPIs

Social KPIs

EnvironmentalKPIs

Fig. 9. Sustainable asset integrity management: Balancing stakeholders demand withsocio-economic and environmental indicators.

C.I. Ossai et al. / Renewable Energy 67 (2014) 143e152150

iii. Cascade new organizational policies to assets operation andmaintain a corporate social image [59].

These objectives can be achieved through utilizing an or-ganizational interfaced function model as shown in Fig. 6 withthe functions of the various units being summarized asfollows:

i. Plant and asset management: Promote sustainabilitythrough decision making and assigning resources forimplementing the requisite changes in AIM.

ii. Sustainability management unit: Coordinate relevantprogrammes necessary for asset lifecycle managementby interfacing with relevant units for feedback andreports.

iii. Environmental and quality control: Ensure that the assetsoperate within key performance indicators (KPIs) as stipu-lated by the regulatory framework.

iv. Plant departments: Responsible for implementing necessaryoperations stipulated for sustainable AIM.

v. Stakeholders: These are responsible for oversight functionsthrough regulation enforcement. The stakeholders also per-form other functions such as R&D, remanufacture, develop-ment of codes and regulatory standards, etc.

3.1. Systematic approach to sustainable AIM

To improve the performance of an asset involves the under-standing of the relevant inputs and the interactions between themand is necessary in achieving an output through a control [23] asshown in Fig. 7. These interactions revolve around the relationshipbetween: (i) the organization and stakeholders, (ii) the workforceand organization and (iii) the workforce and their requisite

activities, as shown in Fig. 8 [60]. In order to improve the integrityof assets therefore involves [60]:

i. Increased awareness of the workforce to understand thestakeholder expectations

ii. Improved interaction amongst different levels ofmanagement

iii. Development of key actions that creates the right balancebetween conflicting interests.

Other experts also believe that empowering the functionalmanagement team through training and education also impactspositively on asset integrity management [60].

Since sustainable AIM would undoubtedly be a complex issuewhen stakeholder demands need to be maintained, striking a bal-ance between the performance of the asset and the key indicators(social, economic, environmental) is a necessary way forward(Fig. 9).

Product lifecycle Phases

Sustainable AIM Framework

Conception Design Testing & Validation

Process Planning &

Manufacturing

CommissioningOperation & Maintenance Decommissioning

Fig. 10. Interaction of product lifecycle phases and sustainable asset integrity management.

C.I. Ossai et al. / Renewable Energy 67 (2014) 143e152 151

3.2. Assets lifecycle performance

In ensuring that assets of renewable plants perform according tothe stipulated performance indicators involve an interactivemechanism for determining the status at all lifecycle stages. Ac-cording to Rahim et al. [61], ensuring the integrity of assets requiresmapping, a critical review to identify the right interfaces andelimination of existing overlaps in the process. This principle isstrategic in determining the technical integrity of an asset at allstages of its lifecycle and the interaction with other performanceindicators as shown in Fig. 10.

Improving asset performance beyond the design life can beachieved through control, compliance, communication, coordina-tion and competence [61,62]. The application of these five qualityprinciples is paramount to downtime minimization according toFig. 11.

4. Conclusions

Implementation of the strategies outlined in this article has thepotential to improve the integrity of assets used in RE plants due tothe integrated organizational function interfaced mitigation ap-proach that makes fault dictation timely. Mitigation strategies pro-vide a holistic asset integrity performance measurement through a

Fig. 11. Factors sustaining asset integrity performance (Adapted from Rahimet al. [61]).

systematic feedback mechanism and by weighted balancing of so-cial, economic and environmental KPIs.

Adoption of sustainable AIM improvement performance princi-ples of control, competence, communication, coordination andcompliance will not only reduce downtime, ageing deterioration,accidents, pollution and incidents but will also aid in improvedlifecycle performance of the assets via a feedback modulatedframework.

Finally, knowledge of the core challenges of RE plant operationis vital for investment planning and R&D in the areas of assetcomponent characteristics and advanced techniques for economicenergy generation.

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