Introduction - Structural Integrity of Offshore Wind Turbines - page 6

in accordance with “accepted engineering practices” and with the approved
reports and operating plans.
Standards and guidelines for the design, fabrication, installation, and
operation of offshore wind turbines 8 have been developed by interna-
tional bodies as well as by individual companies and countries, predom-
inantly in Europe (see Chapter 3). However, none of these standards or
guidelines has been accepted by U.S. agencies, nor has the United States
developed its own. Standards and guidelines exist for other offshore
activities in U.S. waters, such as oil and gas development and waterborne
shipping. Other relevant standards cover items such as the environment
and workplace health and safety. But BOEMRE has not specified any cri-
teria that offshore wind turbine projects must meet to secure approval.

STUDY CHARGE AND SCOPE

In the absence of such standards and guidelines for the United States,
BOEMRE asked the National Research Council (NRC) to review its
approach to overseeing the development and safe operation of wind
turbines on the OCS, with a focus on structural safety. The charge to
the study committee is given in Box 1-2.
The committee's scope was limited to structural safety, in accordance
with discussions with the sponsor at the first committee meeting. 9 Hence,
although the term “Structural and Operating Safety” appears in the com-
mittee's title, the committee limited its treatment of operational safety to
those aspects that could be affected by structural design, fabrication, and
installation. It included within its scope the design, fabrication, and instal-
lation of subsea cables. As illustrated in Figure 1-2, the committee char-
acterized its scope as “from design to commissioning.”
One caveat is that structural integrity cannot be considered in isolation.
In complex engineering systems such as wind turbines, there are non-
structural components and systems whose failure and malfunctioning

8

In this report, “wind energy turbine generators” are often referred to simply as “wind turbines.”
A set of wind turbines is often referred to as a “wind farm.” One or more turbines, when consid-
ered together with the rest of the equipment involved in transferring electricity from the turbines
to shore, can also be referred to as a “wind farm” or, alternatively, a “wind energy power plant.”

9

“Background Information and Study Goals,” presentation to the committee by John Cushing,
BOEMRE, July 28, 2010.