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6 Qualifications Needed by Certified Verification Agents As discussed in Chapter 5, the certified verification agent (CVA) is responsible for ensuring that the design, fabrication, and installation of offshore wind turbine facilities are in accordance with accepted and approved plans and compilations of national and international stan- dards, rules, industry guidelines, and recommended practices (referred to here as “packages of Guidelines”). To perform this work, the CVA must have certain capabilities and experience. This chapter explores qualifica- tions required of third-party reviewers, evaluates various approaches to accrediting a CVA, addresses the qualifications necessary for an offshore wind turbine CVA, and discusses the potential gaps in the process in the initial years of CVA implementation in the U.S. offshore wind industry. SURVEY OF QUALIFICATIONS FOR OTHER THIRD-PARTY REVIEWS Third-party reviews and verification activities are undertaken for var- ious engineered systems, among them offshore oil and gas, marine, and land-based structural design (including wind turbines). This sec- tion explores the qualifications necessary for organizations undertak- ing these verification activities to provide a background for evaluating what qualifications should be required for the offshore wind turbine industry. The qualifications described in this section are presented as examples from other third-party review systems, which have informed the committee’s deliberations on the recommended qualifications for CVAs. 109

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110 Structural Integrity of Offshore Wind Turbines Qualifications Required of Offshore Oil and Gas CVAs The verification process for offshore oil and gas facilities is the one most closely associated with the process envisioned for offshore wind turbines, because they are both mandated by U.S. Department of the Interior reg- ulations as published in the Code of Federal Regulations (CFR) and directed by the Bureau of Ocean Energy Management, Regulation, and Enforcement (BOEMRE), formerly the Minerals Management Service (MMS). Title 30 of the CFR addresses minerals resources, and Parts 250.909 through 250.918 describe the Platform Verification Program (30 CFR 250.909–918) (see Chapter 5). A list of qualifications necessary for the nominated CVA to be approved by the BOEMRE regional supervisor, such as 10 years or more of experi- ence with offshore fixed platform design or active involvement in three or more fixed jacket installations, is not given by 30 CFR 250. However, a review of the nomination requirements and expected activities of the CVA provides a sense of the necessary qualifications. The CVA nomination process for oil and gas facilities is addressed in 30 CFR 250.914. Section (b) lists the information that must be included in the CVA “qualification statement,” including the following: • Previous experience with third-party verification; • Previous experience with design, fabrication, or installation of fixed or floating offshore structures; similar marine structures; and related systems and equipment; • Previous experience with BOEMRE requirements and procedures; • Technical capabilities for the specific project and staff availability; • Size and type of the organization; • Access to necessary technology such as analysis tools and testing equipment; and • Level of work to be performed. The CFR does not include minimum acceptable levels for any of these qualifications, and the evaluation of a CVA’s qualifications is subjective and ultimately the responsibility of the regional supervisor. The following is an overview of what, according to the CFR, is expected of the CVA for each of the three project phases: design, fabrication, and installation.

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Qualifications Needed by Certified Verification Agents 111 Expectations of CVAs for the Design Phase The primary design phase activity (30 CFR 250.916) is to perform an inde- pendent review of the design on the basis of “good engineering judgment” to determine whether the design is suitable and will allow the system to withstand “environmental and functional load conditions appropriate for the intended service life at the proposed location.” The CFR indicates spe- cific areas that must be subjected to the CVA’s independent review for both fixed and floating offshore structures; among them are loading, stresses, and foundations. The design CVA must produce a report of findings that identifies how and by whom the independent review was conducted. Expectations of CVAs for the Fabrication Phase The primary fabrication phase activity (30 CFR 250.917) is to perform an independent review of the fabrication on the basis of “good engineering judgment” to determine whether the structure matches the design docu- ments and plans. Periodic site visits to where the fabrication is taking place are necessary. The CFR specifies several items that must be verified by the CVA during this phase for both fixed and floating offshore struc- tures, including fabricator quality control, material quality, welder qual- ifications, and nondestructive testing. The fabrication CVA must produce a report of findings that identifies how and by whom the independent review was conducted. Expectations of CVAs for the Installation Phase The primary installation phase activity (30 CFR 250.918) is to perform an independent review of the installation on the basis of “good engineering judgment.” This entails reviewing installation plans and procedures and witnessing the installation operations from loadout and towing to launch- ing, uprighting, submergence, and so forth. The CVA is also responsible for evaluating the equipment used and the record keeping that is done. The installation CVA must produce a report of findings that identifies how and by whom the independent review was conducted. In each phase, the CFR emphasizes the use of “good engineering judg- ment.” While there is no definition of this term, its use indicates a prefer- ence for personnel with enough experience to form the basis for exercising

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112 Structural Integrity of Offshore Wind Turbines good engineering judgment. Given the range of activities required for each of the phases, it is clear that to perform the role of a CVA competently, those involved and certainly the person in charge of the process must have direct experience with the activities of that phase. Wind Turbine Project Certification As described in Chapter 3, project certification is a process used to ensure that the equipment and supporting structure are adequate for conditions at the site and meet the site’s requirements. It involves monitoring of activities during manufacturing, transportation, installation, and com- missioning. Project certification also considers the life cycle of the facil- ity and includes provisions for periodic monitoring, inspection, and maintenance. The qualifications for a certification agent vary with the regulator in the area where the wind turbines are to be installed. In some cases, there is no regulatory requirement for project certification, but the operator or developer may need certification to obtain financing or for other reasons. In these cases, certification is generally provided by an orga- nization, such as Germanischer Lloyd or Det Norske Veritas, that has developed its own set of guidelines for designing, installing, and main- taining wind turbine facilities. The organization will certify that the project has met its guidelines and any local jurisdictional requirements. Other organizations, such as Bureau Veritas, that have not developed their own guidelines may also provide certification. In such cases, the qualification for the certifier is its institutional knowledge of the topic through development of detailed guidelines and through its work with the industry. As described in Chapter 3, where such certification is required, it is typically provided by an organization that has been accredited to pro- vide these services. For instance, the German Federal Maritime and Hydrographic Agency accredits organizations to provide certification on projects in Germany. Accreditation is based on evaluations of professional competence, independence, impartiality, and integrity. Accreditation is generally valid for a period of time, after which the review process is repeated to ensure that the organization remains in compliance.

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Qualifications Needed by Certified Verification Agents 113 Qualifications Required for Performance-Based Design Peer Review Standard building codes and industry practice use a prescriptive design approach that does not always lend itself to the design of atypical or unusual structures such as high-rise buildings or buildings with unique architectural features. As noted in Chapter 4, building codes and indus- try practice generally do allow the use of alternative means and methods, one of which is performance-based design (PBD). A peer-review process in support of PBD approaches is used as a means of determining whether a design meets the intent of basic code requirements, is equivalent in terms of safety to a code-compliant structure, and meets project-specific design criteria and performance expectations for the facility. A peer review is not intended to be a critique of the design concept developed by the engineer of record. In some cases, such as for structures in areas of high seismic activity, especially where the design is atypical, the peer review is mandated by regulators, but it may also be implemented by the developer to satisfy expectations of insurers or financiers. One description of this type of peer review comes from the Los Angeles Tall Building Structural Design Council in its publication 2008 Alternative Design Criteria. The council proposes that each project convene a seismic peer-review panel to provide an “independent, objective, technical review of those aspects of the structural design” related to seismic performance. Its recommendation is for a panel of at least three members with “recog- nized expertise in relevant fields” to be selected by the building official of the jurisdiction. (See http://www.tallbuildings.org.) Others Peer-reviewed designs are becoming more common in the assurance of fire protection of buildings as well. The Society of Fire Protection Engi- neers (SFPE) has developed guidelines for the peer-review process in fire protection design (Guidelines for Peer Review in the Fire Protection Design Process, October 2002). With regard to qualifications, the society empha- sizes independence and technical expertise. It gives a specific example of how one can demonstrate technical expertise: the peer reviewer should have the knowledge to prepare an “acceptable design that is similar in

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114 Structural Integrity of Offshore Wind Turbines scope to the design being reviewed.” This definition is attributed to Sec- tion 1.2.1 of the SFPE Engineering Guide to Fire Protection Analysis and Design of Buildings. This document also describes peer reviewers as those who are “qual- ified by their education, training and experience in the same discipline, or a closely related field of science, to judge the worthiness of a design or to assess a design for its likelihood of achieving the intended objectives and the anticipated outcomes.” U.S. REGULATIONS FOR OFFSHORE WIND TURBINE CVA QUALIFICATIONS Language in the current CFR addresses requirements for offshore wind turbines. Sections 705 through 714 of 30 CFR 285 are related to CVAs for offshore renewable energy. Three areas may be covered by the CVA process: the facility design report, the fabrication and installation report, and the modification and repair report. Section 705 describes when a CVA must be used and provides guid- ance on when BOEMRE may waive the use of a CVA for any or all of the three phases (design, fabrication, and installation). Section 706 addresses the CVA nomination process. As in the case of offshore oil and gas facilities, a qualification statement is required that includes the following: • Previous experience with third-party verification; • Previous experience with design, fabrication, repair, or installation of offshore energy facilities; • Previous experience with BOEMRE requirements and procedures; • Technical capabilities for the specific project and staff availability; • Size and type of the organization; • Access to necessary technology such as analysis tools and testing equipment; and • Level of work to be performed. Unlike the regulations of 30 CFR 250, the offshore wind turbine regula- tions require that the verification work be directed by a registered profes- sional engineer. Each U.S. state implements its own professional engineer

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Qualifications Needed by Certified Verification Agents 115 registration process to provide a specific minimum level of work experience and competency, although the experience and competency may not be directly related to offshore wind facilities. BOEMRE would determine whether an organization having international engineers with credentials equivalent to those of a U.S. registered professional engineer would be con- sidered acceptable for providing CVA services. The guidance on activities to be performed at each stage of the project is similar to that provided in Part 250 and summarized in the section on offshore oil and gas CVA above. EVALUATION OF ACCREDITATION APPROACHES Generally, there are two approaches in determining whether a person or organization is qualified to perform CVA activities: project-specific and authorized list. Some of the advantages and disadvantages of each approach with regard to offshore wind turbines are examined below. Project-Specific Accreditation This approach is used by BOEMRE for offshore oil and gas CVA selection and is inherent in the proposed CFR language for offshore wind turbines. A CVA is nominated by the operator for each project and must be approved by the BOEMRE regional director. The regional director is responsible for evaluating the qualifications of the proposed CVA and determining whether the nominee is suitable. This can be cumbersome if the regional director does not have sufficient time, expertise, or staff to devote to these evaluations and could lead to delays in projects as they await approval or to rubber-stamping of nominees with- out proper consideration of their qualifications. However, this approach has the advantage of producing current qualification information from the potential CVA, and the qualification process is readily auditable for each project. No process and no objective criteria are available for use by the regional director in determining whether a nominee is qualified for a given project and scope, and there is no way to estimate how long the determination will take. The process should be clearly defined, and operators should have an expectation of the time required to approve the nominee.

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116 Structural Integrity of Offshore Wind Turbines Authorized CVA List When the CVA process was introduced to the offshore oil and gas indus- try, the authorized list approach was used. Preapproved CVA organiza- tions were identified, and an operator could select one from the list without further approvals or reviews. This had the advantage of clarity and timeliness for the operators and freed regulators from reviewing qualifica- tions for each project that required a CVA. However, the authorized list must be kept current, since personnel available at the time of approval may not be available when the projects get under way. Periodic auditing of the list is required to ensure that it repre- sents qualified organizations. Furthermore, the list creates a barrier to par- ticipation for individuals and organizations that are not on the list, although they may be qualified. To implement an authorized list effectively there should be • A regular review of the authorized organizations, • A process for removal from the list, • A regular opportunity to add new organizations to the list, and • An auditing process to ensure that personnel performing CVA duties are those whose qualifications were cited to get on the list. An authorized list can be advantageous, although it may be just as bur- densome for the regulator, given the work required to maintain the list and ensure that it is used properly. The committee heard from a former director of the MMS Office of Structural and Technical Support, who described how the oil and gas CVA process was implemented. He expressed the opinion that the maintenance of an approved list was impractical given how personnel moved from com- pany to company and the inability of MMS to monitor effectively the expertise of the companies on the list. This led to the abandonment of the list and the move to project-specific approvals of CVAs.1 The difficulty in maintaining an approved list would be similar for the offshore wind indus- try. This difficulty, coupled with the successful use of project-specific approvals for the oil and gas CVA process, makes project-specific lists the preferred approach for CVA approval. 1 Presentation by Thomas Laurendine to the committee, August 10, 2010.

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Qualifications Needed by Certified Verification Agents 117 The International Electrotechnical Commission (IEC) is revising its standard 61400-22 for conformity testing and certification of wind tur- bines. It has established an advisory committee of certification bodies to provide advice on, among other things, harmonization of certification requirements and interpretation of technical requirements. Involvement of BOEMRE with this committee would be useful as a means of interact- ing with other regulators facing similar issues and staying informed on issues relating to wind turbine certification and the accreditation of CVAs.2 OFFSHORE WIND TURBINE CVA QUALIFICATIONS In addition to being independent and demonstrating good engineering judgment, a third-party reviewer should have technical expertise related to the work being reviewed. In evaluating the qualifications of CVA can- didates for offshore wind turbines, their expected areas of expertise should be identified. As the preceding sections show, however, they are not usu- ally identified. The following sections outline the committee’s suggested expectations for a CVA qualified to perform each of the three review phases. The expectations are based on the direct experience of the com- mittee members, reviews of existing guidance documents for offshore wind turbines, and CFR requirements. Design CVA A design CVA should have expertise in the following areas: 1. Identification, specification, and implementation of design limit states. These are especially important for offshore wind turbine designs given the variety of load cases that must be considered under the IEC stan- dards and other relevant guidance and the need to incorporate load conditions not generally encountered for offshore European facilities, including hurricanes and earthquakes. 2. Fatigue and strength design approaches, including the effects of cou- pled wind–wave dynamics. The CVA must be able to understand the techniques used in the analysis and design process and identify whether 2 Report from MT22. http://wind.nrel.gov/public/TC88/Report%20from%20MT22.pptx.

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118 Structural Integrity of Offshore Wind Turbines design assumptions are valid and the conclusions are supported by the results. 3. Determination of the adequacy of proposed design environmental con- ditions. A CVA must understand the prevalent environmental condi- tions affecting the site and be able to assess whether the site-specific criteria developed for the project have been adequately considered in the design approach and the final design. 4. Evaluation of foundation design. Within U.S. waters, a variety of soil types and factors affect foundation design (e.g., scour). The CVA must be able to identify whether the design approach is suitable for local con- ditions and verify that long-term effects such as cyclic degradation and scour have been adequately addressed. 5. Interaction between the foundation and the turbine system. In contrast to the case for offshore oil and gas permanent structures, the inter- action between the wind turbine’s above-water structure and the sub- structure and foundation has a dynamically driven response that must be considered in the design and understood by the CVA to ensure that it has been adequately addressed. 6. Determination of the adequacy of the geotechnical assessment. The quality of soil data can vary greatly depending on who does the investi- gation, where the borings are taken in relation to the foundation, and the age of the data and their interpretation. The CVA must understand these factors and be able to determine whether the soil data are suitable for the foundation design. 7. Performance of design calculations similar to those provided in the design reports. This is not a requirement that independent calculations be performed but that the CVA be able to perform them as necessary. Fabrication CVA A fabrication CVA should have expertise in the following areas: 1. Fabricator quality control. The CVA should be familiar with quality control processes and be able to perform audits of the fabricator’s sys- tems to determine compliance specific to the project. 2. Material quality evaluation. The CVA should understand material traceability procedures and be able to determine whether project

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Qualifications Needed by Certified Verification Agents 119 requirements are suitable and whether the manufacturer is effectively managing these processes for the project. 3. Welder qualifications. The CVA must have a working knowledge of welder qualifications and how they relate to the project and be able to determine whether project qualification requirements are suitable and are being met by the fabricator. 4. Nondestructive testing. Tests for welds and other fastenings, blades, and other structural systems are done to help ensure that fabrication is proceeding according to the design documents. The CVA should be familiar with the project requirements and how such tests are carried out and interpreted. 5. Destructive testing (e.g., full-scale blade tests). In some cases, destruc- tive testing may be called for in project documents to demonstrate that equipment and systems meet specifications (e.g., blades may be tested to failure under certain loading conditions). The CVA should understand the project requirements and how such tests are to be car- ried out and interpreted. 6. Blade materials and fabrication. Blade fabrication is a specialized process with unique use of skin materials and substructure to achieve the desired aerodynamics and strength. The CVA should have expe- rience with the materials used and the fabrication process so that the CVA can evaluate the suitability of the blade manufacturing process and results and determine whether the manufacturer’s quality control process can be relied on to produce blades to the desired specification. Installation CVA An installation CVA should have expertise in the following areas: 1. Evaluation of installation plans and procedures. The CVA must be familiar with how offshore installation activities are carried out and be able to review project procedures and plans for correctness and suitability for site-specific conditions. 2. Witnessing of installation operations including loadout, towing, launch- ing, uprighting, submergence, and so forth. The CVA must have expe- rience with offshore installation activities and have knowledge sufficient to document the activities and identify any anomalous conditions.

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120 Structural Integrity of Offshore Wind Turbines 3. Marine operations. The CVA should be familiar with marine operations from loadout to sea fastening and transportation to the site. This will enable the CVA to document the process and identify any anomalous conditions encountered. 4. Subsea cabling activities including trenching, burial, and connections. The transmission cables used to interconnect the turbines within a field and to connect to shore-based facilities require attention during instal- lation to ensure that they are properly trenched or buried according to the design of the system and that connections are properly completed. The CVA should be familiar with these operations. 5. Offshore construction activities. The CVA must understand how typi- cal offshore construction activities (e.g., launching, lifting, and erecting the facility) are carried out and be able to document that they were implemented successfully and where deviations occurred. 6. Installation equipment. The CVA should have an understanding of the equipment to be used in the installation process and be able to deter- mine that it is being used as intended for the project in a safe and reli- able manner. In addition, the CVA should be able to define the amount of attendance required by the CVA at various offshore activities in conjunction with the installation contractor and BOEMRE. The amount of attendance required should be based on the complexity of the activity and the contractor’s experience with similar activities. Other Aspects of CVA Qualifications The experiences of some committee members and information provided to the committee by presenters indicate that having CVAs for the design phase different from those for the fabrication and installation phases is acceptable in current offshore oil and gas practice. No restrictions on the assignment of CVA responsibilities to different organizations for different phases are imposed by 30 CFR 250. In practice, organizations with exper- tise in design do not necessarily have expertise in fabrication or installa- tion activities. Thus, it is expected that different CVAs will be responsible for different phases unless it can be demonstrated that a single individual or organization has sufficient expertise as outlined above to direct all or a combination of the phases.

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Qualifications Needed by Certified Verification Agents 121 Local environmental, soil, and marine traffic conditions vary greatly throughout U.S. coastal waters. The variations affect loads that control tower, foundation, and turbine designs; installation conditions such as local sea swells; pile-driving requirements; and a variety of other factors. Expertise with conditions in one location may not be directly applicable to other locations. In some cases, knowledge unique to a particular loca- tion (e.g., seismic effects offshore California) may be required. The expertise of the CVA should be considered in relation to the location of the project to determine whether that expertise is applicable to local requirements. Finally, in the committee’s opinion, a CVA should have a quality assur- ance plan that addresses the processes used in the CVA activities and the record-keeping ability necessary to track the project adequately and doc- ument results. Such plans may, but are not required to, adhere to Inter- national Organization for Standardization or other standards for quality assurance, but they should be maintained in such a way that a compliance audit could be conducted and passed. Adherence to such a plan helps ensure that data are properly tracked (e.g., nondestructive evaluation test reports and project interim reports) and that the CVA activities capture all necessary aspects of the project. FILLING THE EXPERIENCE GAP To date, no large-scale offshore wind turbine projects have been designed for or installed in U.S. waters. As described in Chapter 3, while a number of projects have been installed in European countries, the local design conditions (e.g., hurricanes) expected for U.S. facilities have not been addressed in detail, and potential fabrication and installation obstacles have not been encountered. Thus, there is a potential gap in experience that will affect the ability of a CVA to review the activities of designers, fabricators, and installers effectively, because the CVA will be learning side-by-side with the principal participants in the projects. Experience in regulating the offshore wind industry is lacking. BOEMRE has a long history of regulating the U.S. offshore oil and gas industry, and its familiarity with operators, designers, fabricators, and installation contractors is invaluable in evaluating the expertise and qualifications of potential CVAs. This familiarity does not exist for the

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122 Structural Integrity of Offshore Wind Turbines offshore wind industry, and BOEMRE lacks staff with experience in regulating, designing, installing, or operating such facilities. The lack of experience within BOEMRE with regard to offshore wind turbine facilities could inhibit its ability to provide effective regulation. One of its roles within the CVA process for offshore renewable projects is to determine whether a CVA is required and whether the proposed CVA is suitable for the tasks assigned. This role is difficult to accomplish with- out experienced, dedicated staff. It is vital that BOEMRE act in a timely fashion to hire staff as described in Chapter 4 in the section “Implementa- tion: Capacity and Expertise” to fulfill its regulatory role. The committee believes that the CVA process can produce valuable information for BOEMRE with regard to the design and installation of wind turbine projects in the United States. The details provided through CVA reports during the course of the projects should be carefully reviewed by BOEMRE and evaluated for information that may lead to better regu- lation or better guidance documents for the industry. This would not place additional burdens on the CVA or on developers and contractors, but it would require BOEMRE to dedicate staff to this task. BOEMRE may also wish to consider creating a panel of industry experts to advise it for the duration of the first several projects. Such a panel could provide BOEMRE with feedback and guidance on the sub- mitted design documents and the plans for fabrication and installation. This group of experts would also benefit BOEMRE and the industry as they implement the first several offshore wind turbine farms in U.S. waters. The panel would supplement the CVA for the project and would bridge the experience gap for both the industry and the regulator. It would also help disseminate lessons learned throughout the industry if the panel were tasked with documenting its findings and recommenda- tions at the completion of its mandate. Such a panel would need a range of expertise similar to that described in the section on offshore wind tur- bine CVA qualifications. Ideally, the panel would have expertise in design of offshore wind or oil and gas structures; offshore transportation and installation, particularly for fixed structures; and structural engineering and fabrication with a preference for experience specific to offshore wind. Panelists could come from a variety of backgrounds and could include developers, designers, representatives from academia, and representatives

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Qualifications Needed by Certified Verification Agents 123 from regulatory bodies. While establishing a panel that meets all those requirements may be impractical, the broader the range of expertise, the more effective the panel will be. In Chapter 4 in the section “Overview of Projected BOEMRE Role,” the committee noted that BOEMRE may wish to use such an expert panel to assist in the initial development of the goal-based standards and then in the continuous monitoring and evaluation of the standards and regula- tions. If desired, a single panel could serve all of these purposes. To eliminate concerns about conflict of interest, controls would be needed to ensure that those impaneled did not use their appointment as a means to promote their business or gain leverage for future work as CVAs or as principals in offshore wind farm work. This is essentially an admin- istrative detail that BOEMRE would need to address and implement. FINDINGS AND RECOMMENDATIONS FOR TASK III Task III of the statement of task calls for the committee review the expected experience level, technical skills and capabilities, and support equipment and computer hardware/software needed to be considered a qualified CVA. Findings, Task III Based on a review of the implementation of the CVA process for offshore oil and gas facilities, the proposed CFR language for an offshore wind CVA, and how other engineered systems implement third-party reviews, the following are the committee’s key findings with regard to CVA qualifications. 1. A qualified CVA must be a. Independent and objective, with no involvement in the scope of work being reviewed (i.e., design, fabrication, or installation); b. Experienced in performing scopes of work similar to that being reviewed, with detailed knowledge of the codes and standards being applied; familiarity with the approaches proposed by the developer; and the technical expertise and engineering judgment to verify assumptions, conclusions, and results independently; and

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124 Structural Integrity of Offshore Wind Turbines c. Directed by a registered professional engineer (or international equivalent). The intent of this requirement is to establish a baseline level of experience and qualifications for the CVA lead. It is the opin- ion of the committee that this goal can be achieved through both U.S. and non-U.S. professional registrations. 2. A CVA for the design stage must have expertise in a. Identification, specification, and implementation of design limit states; b. Fatigue and strength design approaches, including the effects of coupled wind–wave dynamics; c. Determination of the adequacy of proposed design environmental conditions for the site; d. Evaluation of foundation design; e. Evaluation of interaction between the foundation and the turbine system; f. Determination of the adequacy of the geotechnical assessment; and g. Performance of design calculations similar to those provided in the design reports. This is not a requirement that independent calculations be performed but that the CVA be able to perform them as necessary. 3. A CVA for the fabrication stage will need expertise in a. Fabricator quality control, b. Material quality evaluation, c. Welder qualifications, d. Nondestructive testing, e. Destructive testing (e.g., full-scale blade tests), and f. Blade materials and fabrication. 4. A CVA for the installation stage will need expertise in a. Evaluation of installation plans and procedures; b. Witnessing of installation operations including loadout, towing, launching, uprighting, submergence, and so forth; c. Marine operations; d. Subsea cabling activities including trenching, burial, and connections; e. Offshore construction activities; and f. Installation equipment.

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Qualifications Needed by Certified Verification Agents 125 5. The CVA for design, for fabrication, and for installation need not be the same organization or person, and it is unlikely that a single person would have sufficient expertise to perform effectively as CVA for all phases. 6. It would be beneficial, though not essential, for a CVA to have experi- ence in third-party reviews and in interacting with regulatory agencies. 7. Given the variety of controlling environmental loads (e.g., hurricanes, seismicity, icing) and installation requirements (e.g., mudslide areas, tidal erosion effects) in U.S. waters, the CVA’s experience should be related to the installation location. 8. Experience with the use of project-specific CVA approvals in the offshore oil and gas industry indicates that project-specific approval of CVAs is better than maintenance of a list of BOEMRE-accepted CVAs. Recommendations, Task III The committee recommends the following with regard to CVA qualifications: 1. In evaluating potential CVAs, BOEMRE should seek organizations and individuals that a. Are independent and objective; b. Have experience, technical expertise, and engineering judgment suf- ficient to verify assumptions, conclusions, and results independently; c. Have experience with the dominant environmental effects for the project location (e.g., earthquake-resistant design experience for offshore West Coast locations); d. Have experience in the areas described in the findings section above for the CVA tasks (i.e., design, fabrication, and installation) for which they are nominated; e. Have clearly defined roles and responsibilities with adequate over- sight by a registered professional engineer (or international equiva- lent); and f. Have an auditable quality plan for the processes and record keeping involved in the CVA activities. 2. BOEMRE should hire sufficient staff with adequate expertise (as described in Chapter 4 in the section “Implementation: Capacity and

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126 Structural Integrity of Offshore Wind Turbines Expertise”) to oversee the development of wind farms in U.S. waters by the end of calendar year 2011. 3. BOEMRE should approve CVAs on a project-specific basis as opposed to maintaining an approved list of qualified CVAs. 4. BOEMRE should actively manage the CVA process for offshore wind facilities by disseminating lessons learned from the CVA process to promote good practices to the industry. 5. BOEMRE should consider creating an expert panel to provide feed- back and guidance for the initial offshore wind development projects as a means to fill the experience gap for both industry and regulators. 6. BOEMRE should actively participate in the IEC Wind Turbines Cer- tification Bodies Advisory Committee as a means of staying informed on issues relating to wind turbine certification and the accreditation of CVAs.