Structural integrity of offshore wind turbines : oversight of design, fabication, and installation

193 Pages·2011·1.28 MB·English

by  Transportation Research Board

TRANSPORTATION
RESEARCH
BOARD
Structural Integrity of Offshore Wind Turbines
SPECIAL
Oversight of Design, Fabrication, and Installation
REPORT 305
The United States is poised to begin building its first offshore wind energy power S Structural Integrity
p
projects. To facilitate the orderly development of offshore wind energy and support e
c
the stable economic development of this nascent industry, the United States needs ia
l R
a set of clear requirements that can accommodate design development. ep of Offshore
In this study, sponsored by the U.S. Department of the Interior’s Bureau of Ocean o
r
Energy Management, Regulation, and Enforcement (BOEMRE), the committee recom- t 3
0
mends that BOEMRE develop a set of performance requirements that establish goals 5
Wind Turbines
and objectives with regard to structural integrity, environmental performance, and
energy generation. Because the committee found that the risks to human life and the
S
environment associated with offshore wind farms are substantially lower than for other
t
r
industries such as offshore oil and gas, it suggests that an approach with significantly less u Oversight of Design,
regulatory oversight may be taken for offshore wind farms. Under this approach, indus- c
t
try would be responsible for proposing sets of standards, guidelines, and recommended u Fabrication, and Installation
r
practices that meet the performance requirements established by BOEMRE. a
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TRANSPORTATION RESEARCH BOARD
OF THE NATIONAL ACADEMIES
Structural Integrity of Offshore Wind Turbines: Oversight of Design, Fabrication, and Installation - Special Report 305
MARINE BOARD
Chair: Michael S. Bruno,Stevens Institute of Technology, Hoboken, New Jersey
Vice Chair: Thomas M. Leschine,University of Washington, Seattle
Steven R. Barnum,Hydrographic Consultation Services, Suffolk, Virginia
Jerry A. Bridges,Virginia Port Authority, Norfolk
Mary R. Brooks,Dalhousie University, Halifax, Nova Scotia, Canada
James C. Card,Maritime Consultant, The Woodlands, Texas
Stephen M. Carmel,Maersk Line Limited, Norfolk, Virginia
Edward N. Comstock,Raytheon Company, Sudbury, Massachusetts
Stephan Toni Grilli,University of Rhode Island, Narragansett
Douglas J. Grubbs,Crescent River Port Pilots Association, Metairie, Louisiana
Frederick J. Harris,General Dynamics, San Diego, California
Judith Hill Harris,City of Portland, Maine
John R. Headland,Moffatt & Nichol Engineers, New York, New York
John M. Holmes,Port of Los Angeles, San Pedro, California
Ali Mosleh,University of Maryland, College Park
George Berryman Newton,QinetiQ North America, Marstons Mills, Massachusetts
Patrick Ernest O’Connor,BP America, Inc., Houston, Texas
Robert W. Portiss,Tulsa Port of Catoosa, Oklahoma
Peter K. Velez,Shell International Exploration and Production, Inc., Houston, Texas
John William Waggoner,HMS Global Maritime, New Albany, Indiana
TRANSPORTATION RESEARCH BOARD
2011EXECUTIVE COMMITTEE OFFICERS
Chair: Neil J. Pedersen,Administrator, Maryland State Highway Administration,
Baltimore
Division Chair for NRC Oversight: C. Michael Walton,Ernest H. Cockrell Centennial
Chair in Engineering, University of Texas, Austin (Past Chair, 1991)
Vice Chair: Sandra Rosenbloom,Professor of Planning, University of Arizona, Tucson
Executive Director: Robert E. Skinner, Jr.,Transportation Research Board
Copyright © National Academy of Sciences. All rights reserved.
Structural Integrity of Offshore Wind Turbines: Oversight of Design, Fabrication, and Installation - Special Report 305
SPECIAL REPORT 305
Structural Integrity
of Offshore Wind
Turbines
Oversight of Design,
Fabrication,and Installation
Committee on Offshore Wind Energy Turbine
Structural and Operating Safety
TRANSPORTATION RESEARCH BOARD
OF THE NATIONAL ACADEMIES
Transportation Research Board
Washington, D.C.
2011
www.TRB.org
Copyright © National Academy of Sciences. All rights reserved.
Structural Integrity of Offshore Wind Turbines: Oversight of Design, Fabrication, and Installation - Special Report 305
Transportation Research Board Special Report 305
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Copyright 2011 by the National Academy of Sciences. All rights reserved.
Printed in the United States of America.
NOTICE: The project that is the subject of this report was approved by the Governing
Board of the National Research Council, whose members are drawn from the councils
of the National Academy of Sciences, the National Academy of Engineering, and the
Institute of Medicine. The members of the committee responsible for the report were
chosen for their special competencies and with regard for appropriate balance.
This report has been reviewed by a group other than the authors according to the pro-
cedures approved by a Report Review Committee consisting of members of the National
Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.
This study was sponsored by the Bureau of Ocean Energy Management, Regulation,
and Enforcement, U.S. Department of the Interior.
Cover design by Debra Naylor, Naylor Design, Inc.
Cover photo: Middelgrunden offshore wind turbines in the strait of Øresund, outside
Copenhagen harbor, Denmark. (Photo by Tore Johannesen, iStockphoto.)
Typesetting by Circle Graphics.
Library of Congress Cataloging-in-Publication Data
National Research Council (U.S.). Committee on Offshore Wind Energy Turbine
Structural and Operating Safety.
Structural integrity of offshore wind turbines : oversight of design, fabrication, and
installation / Committee on Offshore Wind Energy Turbine Structural and Operating
Safety, Marine Board, Transportation Research Board of the National Academies.
p. cm. — (Transportation research board special report ; 305) 1. Offshore structures—
Design and construction—Safety measures—Government policy—United States.
2. Wind turbines—Design and construction—Safety measures—Government policy—
United States. 3. Wind power plants—United States—Safety measures. 4. Electric
power-plants, Offshore—United States—Safety measures. I. Title.
TC1665.N38 2011
621.4′53—dc22
2011004767
ISBN 978-0-309-16082-7
Copyright © National Academy of Sciences. All rights reserved.
Structural Integrity of Offshore Wind Turbines: Oversight of Design, Fabrication, and Installation - Special Report 305
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Copyright © National Academy of Sciences. All rights reserved.
Structural Integrity of Offshore Wind Turbines: Oversight of Design, Fabrication, and Installation - Special Report 305
Copyright © National Academy of Sciences. All rights reserved.
Structural Integrity of Offshore Wind Turbines: Oversight of Design, Fabrication, and Installation - Special Report 305
Committee on Offshore Wind Energy Turbine
Structural and Operating Safety
R. Keith Michel,Herbert Engineering Corporation, Alameda,
California, Chair
Bruce R. Ellingwood,Georgia Institute of Technology, Atlanta
George M. Hagerman, Jr.,Virginia Coastal Energy Research Consortium,
Virginia Beach
Jan Behrendt Ibsoe,ABS Consulting, Inc., Houston, Texas
Lance Manuel,University of Texas at Austin
Walt Musial,National Renewable Energy Laboratory, Golden, Colorado
Robert E. Sheppard,Energo Engineering, Houston, Texas
Emil Simiu,National Institute of Standards and Technology,
Gaithersburg, Maryland
Susan W. Stewart,Pennsylvania State University, State College
David J. Wisch,Chevron Energy Technology Company, Houston, Texas
Staff
Madeline G. Woodruff, Study Director
Copyright © National Academy of Sciences. All rights reserved.
Structural Integrity of Offshore Wind Turbines: Oversight of Design, Fabrication, and Installation - Special Report 305
Copyright © National Academy of Sciences. All rights reserved.
Structural Integrity of Offshore Wind Turbines: Oversight of Design, Fabrication, and Installation - Special Report 305
Preface
Although many of the world’s largest wind farms are located in the
United States, these installations are entirely land based. Land-based
wind resources are plentiful but are located principally in the central
regions of the country, remote from the major population centers where
electricity demand is growing but transmission line access and capacity
are limited. There are obstacles to installing an enhanced transmission
system capable of connecting land-based wind farms to the highly pop-
ulated areas, particularly with regard to permitting.
Costs related to installation and maintenance are significantly higher
for offshore wind farms than for those located on land. However, offshore
wind farms offer a number of advantages that could offset these higher
costs. Offshore installations can be located close to coastal metropolitan
areas, reducing transmission infrastructure requirements. The intensity
of offshore wind energy is also greater, allowing the offshore wind tur-
bine to operate at greater efficiencies than a comparable land-based
installation.
There are currently offshore wind projects planned along the U.S.
East Coast, the Gulf of Mexico, and the Great Lakes. To date, most off-
shore wind farms have been located in the waters of the European and
Scandinavian nations—Germany, Denmark, and the United Kingdom
being the most important. These countries have been the leaders in both
technological and regulatory development related to offshore wind power
generation. The international standards for offshore wind turbine design
and certification established by the International Electrotechnical Com-
mission (IEC) are formally recognized in European national regulations.
Some of these national regulations also recognize the guidelines and reg-
ulations developed by classification societies.
vii
Copyright © National Academy of Sciences. All rights reserved.
Structural Integrity of Offshore Wind Turbines: Oversight of Design, Fabrication, and Installation - Special Report 305
viii Structural Integrity of Offshore Wind Turbines
In the United States, where offshore wind energy has been much less
of a focus, regulatory development has lagged. As a result, permitting of
sites in U.S. waters is proceeding without a clear set of national regula-
tions for the design, fabrication, installation, and commissioning of off-
shore wind turbines. The Minerals Management Service (MMS), which
has been renamed the Bureau of Ocean Energy Management, Regula-
tion, and Enforcement (BOEMRE), is responsible for the orderly, safe,
and environmentally responsible development of offshore renewables on
the outer continental shelf. BOEMRE requested that the Transportation
Research Board’s (TRB’s) Marine Board conduct a study to guide the
agency in the regulation and technical oversight of the nascent offshore
wind energy industry in the United States.
Astudy committee consisting of 10 members from academia, national
research centers, and industry was appointed by the National Research
Council (NRC). Members have expertise in structural engineering, wind
energy, regulation, third-party verification in offshore platforms and
wind turbines, and oceanography. Biographical sketches of the committee
members appear at the end of this report. The report represents the con-
sensus opinion of the committee members and presents the committee’s
findings and recommendations on the standards and practices that could
be used in oversight of U.S. offshore wind installations, the role of third-
party reviewers and BOEMRE in overseeing of the design and construc-
tion of offshore wind turbines, the necessary qualifications of third-party
reviewers, and the selection process for identifying and approving third-
party reviewers.
The committee met three times over a 5-month period. These face-
to-face meetings were supplemented by numerous conference calls. The
committee listened to presentations from a wide range of stakeholders,
including state and federal regulators, standards development organi-
zations, wind farm developers, turbine manufacturers, and research
scientists and engineers with expertise in the wind energy industry. The
committee also reviewed various studies and workshop proceedings
sponsored by BOEMRE. These resources proved invaluable as the com-
mittee discussed alternative approaches to oversight processes and for-
mulated the ideas that are presented in this report.
Copyright © National Academy of Sciences. All rights reserved.