OffshOre wind services - GL Garrad Hassan

This brochure was produced with consideration for the environment. It is printed on paper that is
100% recycled and has an FSC accreditation.
All information correct at time of print June 2011
Renewable energy consultants
Technical by nature...
Offshore wind SErvices
www.gl-garradhassan.com

Contents
THE technical authority
on OFFSHORE wind energy
GL Garrad Hassan is the world’s largest
renewable energy consultancy. Dedicated
to serving the renewables industry it offers
independent technical and engineering
services, products, and training to the wind,
wave, tidal and solar sectors.
Although the GL Garrad Hassan name is
new, the company has a rich heritage. It
was created by the integration of specialist
companies that, united under a single brand,
form the renewable energy consulting
division of the GL Group and deliver
unrivalled depth and breadth of service
4 Front end engineering and design (FEED)
6 Geotechnical and geophysical survey management
8 Metocean analysis
10 WindFarmer software
10 Stakeholder consultations
11 Project management services
15 Vessel assurance and marine/HSE audit
16 Installation and de-commissioning services
18 Marine warranty services
19 Operations and maintenance (O&M)
20 Bladed software
22 Wind speed and energy analysis
23 Due diligence
24 Structural design and analysis
26 Short-term forecasting
28 Electrical design and analysis
28 Vessel design
29 Strategic studies
30 Training courses
to clients at all stages of the renewable
energy project lifecycle. GL Garrad Hassan
is the recognised technical authority on
wind energy and, in this respect, there is no
other company with the same volume of
experience and international presence.
GL Garrad Hassan is a consulting company
and recognised technical authority on wind
energy. It has no equity stake in any device
or project. This rule of operation is central
to its philosophy and sets it apart from
many competitors, as well as underlining its
independence.
About GL Garrad Hassan
Unrivalled experience for the
life of an offshore wind project
GL Garrad Hassan is the premier provider
of life cycle marine and engineering services
to the offshore wind industry. It brings
together the offshore experience of Noble
Denton, the renewables expertise of Garrad
Hassan and the technical excellence of
Germanischer Lloyd within a single business
unit. In addition, as part of the GL Group,
it has access to experts from the new oil
and gas division of GL Noble Denton, who
has many years experience of supporting
offshore projects within their own industry,
much of which is entirely relevant to offshore
wind projects.
The skills and expertise offered encompass:
Project management
Commercial analysis / market strategy
Wind yield analysis
Transportation and installation management
Turbine technology
Structures and foundations
Geotechnical engineering
Power transmission and control /
communications cables
High voltage electrical systems design / grid
connection
Health and safety
Client representation offshore or onshore
Marine engineering
Marine warranty services
Metocean services
Due diligence for banks and investors
“Wind energy will play a vital role
in the world’s future energy supply.
In crowded countries it is the only
way in which wind can achieve its
full potential and be developed on a
‘utility scale’. For some time it has been
a question of when rather than if it
happens. In Northern Europe, and in
the UK in particular, its time has come.
Fortunately we at GL Garrad Hassan
were ready for it and already have
significant experience under our belts
in all areas of activity. We have a huge
range of projects in progress including
the project management of the design,
build, and installation of the world’s
largest offshore wind farm. Our
heritage is wind energy on one side
and offshore engineering and maritime
services on the other - the perfect
combination for offshore wind.”
Dr. Andrew Garrad, President
2 3

Front end engineering and design (FEED)
The key decisions required to
determine the success of an offshore
wind farm are typically taken in the
development stages
Case Study: Gwynt y Môr FEED
Client: NPower Renewables
GL Garrad Hassan was lead contractor for the Gwynt y Môr FEED study. The scope of
this extensive project included wind turbine analysis, layout development, structural
design/analysis, electrical system design/analysis, site investigation specification,
market analysis, procurement strategy and operation and maintenance design/
analysis.
These decisions often have significant
impact on other aspects of the project and,
in order to optimise that project, the owner
must understand the implications of these
decisions at the earliest possible stage.
The purpose of the Front End Engineering
and Design (FEED) process is to explore
the options available and evaluate their
subsequent technical and commercial
implications. FEED can also identify specific
problem areas at an early stage, enabling
the owner to mitigate risk prior to engaging
with the supply chain and therefore realise
significant commercial savings.
A FEED study will deliver:
Early understanding of project costs and
economics
Optimal selection of design concepts
Identification of project specific supply chain
and evaluation of its capability to deliver
A well defined procurement strategy and the
basis for an effective tendering process
FEED is a multi-disciplinary process across a
wide range of specialist areas, which may
include:
Metocean analysis
Geotechnical engineering
Wind turbine technology
Wind farm layout design
Design of offshore structures
(for wind turbines and substations)
Vessel design and selection
Fabrication technology
Design of electrical systems and grid
connection
Subsea cable engineering
Marine transportation and installation
methodology
Naval architecture
Port facility review
Market intelligence
Operations and maintenance strategy
Health and safety planning
Procurement planning (including developing
technical specifications)
Programming and risk analysis
Development of capital and operating cost
budgets
Case Study: Teesside FEED
Client: EDF Energy
GL Garrad Hassan was the lead contractor responsible for implementing a FEED
study for the Teesside Offshore Wind Farm on behalf of EDF Energy. GL Garrad
Hassan’s experts delivered this wide-ranging study including: project management,
wind turbines, layout design and analysis, offshore structures, electrical system,
operations and maintenance, marine installation, cable installation, health and
safety, risk management and procurement support.
When undertaking FEED studies, GL Garrad
Hassan provides project managers and a
team of experts that are at the forefront
of their individual disciplines, as well as
having significant practical and commercial
experience from the development,
construction and operation of numerous
offshore renewables projects.
4 5

Geotechnical and geophysical survey management
GL Garrad Hassan has extensive
skills and experience in geophysical
and geotechnical engineering for
offshore renewables projects
Support to geotechnical and
geophysical investigation
GL Garrad Hassan combines its project
management, maritime and technical support
skills to assist clients during geotechnical
and geophysical investigations. Its team
has experience of supporting the whole
project life – it can therefore ensure that
the surveys are optimised to fulfil the future
requirements of the development.
The full survey management support services
offered include:
Design support
GL Garrad Hassan offers a full range of
geotechnical design services to support the
structural design of foundations, turbines and
the laying of cables. These services include:
Interpretation of geotechnical soil profiles
Calculation of pile capacities
Bearing capacity assessment
Derivation of design soil springs
(P-y, T-z, Q-z curves)
Support in obtaining design certification
Assessing potential for local scour and global
seabed movement
Driving induced fatigue analysis
Finite element analysis of soil/structure
interaction
Stability analysis of rock dumps
Construction support
GL Garrad Hassan offers a full range of
geotechnical support services during the
construction phase of an offshore wind
project. These include:
Pile driveability and hammer selection studies
Assessment of pile self weight penetration
Assessment of pile stability in the temporary
condition
Post installation driving fatigue analysis
Back analysis of driving records to
refine/prove design
Mudmat design and associated seabed
stability analysis
Jack-up site-specific assessment including
jack-up spudcan penetrations, ultimate
foundation capacities, fixity, punch-through
potential, spudcan-pile interaction, spudcanfootprint
interaction, jack-up leg extraction,
seabed remediation and scour assessments.
Desk studies and geological site
selection
A geological desk study assesses the
anticipated ground conditions at a site,
based on all available data, and starts the
development of a site geological model.
Through the desk study assessment,
GL Garrad Hassan can advise on site
selection and layout, assist in the
preliminary design of infrastructure and
make recommendations for any relevant
future investigations that may be required
to further understand the site.
GL Garrad Hassan’s geological desk studies
not only consider data from publically
available sources but also draw upon
borehole and geophysical data from GL
Group division, GL Noble Denton’s archive.
This unique database has over 4,100 borehole
and geophysical reports from subsea
locations all over the world.
Planning of survey activities
Development of scope of works
Preparation and letting of tender documents
Tender analysis and recommendations for
award
Jack-up / vessel suitability assessment
Project management support services
Marine warranty surveys
Offshore client representation / supervision
of field work
Technical support, data assessment
Health, safety and environmental support
Specification and supervision of onshore
laboratory testing
Review of final reports
Correlation and interpretation of field data
Cable route analysis
6 7

Metocean analysis
Experts with a thirty year
track record of providing high
quality metocean advice
Understanding the meteorological and
oceanographic (metocean) environment is
a primary concern in the development and
operation of offshore structures. Via the
GL Group, GL Garrad Hassan has access to
GL Noble Denton’s metocean experts, who
have a thirty year track record of providing
high quality metocean advice and analysis
to the offshore and coastal engineering
industries and have conducted over 8000
separate studies. Through advanced analysis
of measured, modelled and remotely-sensed
data, the experts seek to quantify the effects
of the physical environment on marine
infrastructure and operations.
In particular they help to solve metocean
related engineering issues associated with:
The design and operation of fixed and
floating structures
Coastal infrastructure, including ports,
harbours, breakwaters and pipelines
Operational planning and downtime
assessment
Marine transportation
Jack-up approvals
To complement these activities, the
department also offers a range of nonanalytical
services including metocean/
weather forecasting contractor selection and
management, technical tender preparation
and bid assessment.
8
9

WindFarmer software
Project management services
WindFarmer has been developed
for the design of wind farms both
onshore and offshore
GL Garrad Hassan offers project
management support across the
project lifecycle
Wind farm design software
WindFarmer has been developed by
GL Garrad Hassan for the design of wind
farms both onshore and offshore, maximising
the energy produced while taking site
constraints into account. Users gain the
competitive advantage and accuracy that
comes from over 25 years of expert wind
energy know-how.
Stakeholder consultations
GL Garrad Hassan has undertaken very
detailed studies of large offshore works and
produced new models to describe them.
Special adjustments can therefore be applied
for the additional array effects found in very
large wind farms.
WindFarmer users can process the
meteorological data to generate the wind
statistics. Wind farm energy analyses predict
annual yield of the wind farm as a whole
or the detailed performance of individual
turbines under specific wind conditions.
Site conditions features enable the user to
identify the IEC class of turbine required for
the site. Environmental modelling tools help
analyse the design for noise or visibility from
the shore or radar stations.
As well as being central to the design process,
WindFarmer can provide invaluable data
for warranty testing, assessing operational
performance and short-term forecasting.
Available in ten languages, WindFarmer is
supported internationally by local GL Garrad
Hassan engineers who know the market and
can offer advice and training.
Highly skilled and dynamic experts combine
practical project management with high-end
analytical engineering expertise to deliver
fast, reliable and innovative solutions for the
most complex of projects.
As specialists in managing all interfaces,
through all phases of the project, GL Garrad
Hassan’s team ensures that projects are
delivered on schedule and within budget.
They can either work as part of an integrated
project team with the client or provide a
complete project management service for all
aspects of the project in a ‘one-stop-shop’
approach.
Integrated within these project management
services is GL Garrad Hassan’s health and
safety management expertise. The specialist
offshore health and safety team work with
clients to ensure projects are managed
to the latest health and safety legislation
and industry best practice. The services
they deliver range from reviewing clients
existing systems and procedures through
to establishing new management systems
and supporting clients in their effective
implementation.
In this field, GL Garrad Hassan’s service
offering includes:
GL Garrad Hassan provided project
management services to the first major
offshore project in the UK – North Hoyle,
and is currently the project management
contractor on the Thanet project which will
be the largest offshore wind farm in the
world. In addition, it is providing project
management services for the Borkum West II
and Dudgeon offshore projects.
Via the GL Group, GL Garrad Hassan is able
to utilise specialist experts from GL Noble
Denton, who possess all the marine and
large-scale project management experience
that might be required to meet the
requirements of renewables clients.
Project management
Survey management
Procurement management
Third party inspection
Construction management
Transportation and installation management
Offshore installation management
Testing and commissioning management
Decommissioning works management
Health and safety management
Using an independent and impartial
organisation to conduct a stakeholder
consultation is crucial for ensuring fairness
and transparency for all stakeholders. GL
Garrad Hassan’s team of in-house industrial
psychologists have detailed experience of
conducting stakeholder consultations, using
practical research methods to measure the
attitudes and opinions of stakeholders.
Using surveys, interviews and workshops, the
views of stakeholders can be collected and
analysed to provide a clear picture of the
issues that can subsequently be addressed
by wind farm developers. Early consultation
can even help improve project management
through the integration of local knowledge.
Consultations will also help project
information to be communicated, helping
to spread awareness and understanding
about the wind farm development. GL
Garrad Hassan’s experience in this area was
recently applied on the Thanet offshore wind
project (based off the coast of Kent) – which
is positioned to be the largest operational
offshore wind farm in the world.
10 11

Project management services
Case Study: North Hoyle Wind Farm
Client: Npower Renewables
Case Study: Lynn and Inner Dowsing Offshore Wind Farms
Client: Centrica Renewable Energy Ltd
GL Garrad Hassan provided specialist technical, commercial, project management
and health and safety services to support the development of North Hoyle Wind
Farm from the initial planning phases, right through to the final commissioning of
the farm.
Tasks undertaken included: specifications for onshore construction facilities,
installation procedure and vessel specification, cost study for the complete
development, cable installation study, extended life and decommissioning studies,
tender preparation, including technical specifications for the main EPC contract,
contractors review, pipeline and beach crossing agreements, construction audit of
vessel modifications, onshore and offshore client representation across all project
phases, health and safety audits and environmental monitoring activities, plus,
commercial and project close-out issues.
GL Garrad Hassan provided technical and project management support for the
development of these projects over a four-year period.
Services provided included: project management, commercial and contract
management, contracting strategy guidance, production of technical specifications,
preparation of tender document and tender review, geotechnical site investigations,
foundation conceptual design work, design verification, electrical design and grid
connections, offshore client representation and safety management system support.
12 13

Project management services
Vessel assurance and marine/HSE audit
Case Study: Thanet Offshore Wind Farm
Client: Vattenfall / Thanet Offshore Wind Ltd
GL Garrad Hassan provided the complete project
management service for the development of the
Thanet Offshore Wind Farm. Its experts delivered
technical and project management support from
the early pre-project phase of the work in 2005
through to completion of offshore works and the
handover of the wind farm in late 2010. It has also
provided over 50 members of staff to sit within the
final construction team.
Services delivered include:
FEED studies to develop the preferred technical
solutions
Support to the environmental impact assessment
and consenting process
Managing the tender process including issue
of tender documents all review work and
recommending contractors
Management of the civil engineering works at
Richborough Power station.
Design reviews
Inspections of all factory works
Project management and co-ordination of all
offshore works – foundations, cables, towers and
turbines.
Principal contractor for the foundation installation
works (under a separate contract).
Interface management
Maintaining risk registers and managing risk on the
project
Management of health safety and safety on the
project
Appointed as CDM Coordinator
Testing and commissioning works
Running the onshore support base
Hand-over of the completed wind farm
(planned for late 2010).
Vessels need to comply with
IMCA and meet HSE standards
To ensure that the nominated vessels
comply with IMCA and that HSE standards
are met, GL Garrad Hassan conduct audits of
the vessels according to GL Group division
procedures, GL Noble Denton’s guidelines,
industry standards and its own quality
documentation.
There are many types of vessel which may
be nominated to undertake a specific work
scope on an offshore wind farm project.
GL Garrad Hassan tailors its ‘fit for purpose’
inspections to take this in to account and
conducts audits of the vessel that cover both
the vessel health and safety and its suitability
to conduct the proposed scope
of work.
To determine if a vessel is ‘fit for purpose’ the following are
considered:
The capabilities of the nominated vessel
Competence of the officers and crew
The operation that the vessel is expected to complete
Operational area
Water depth
Port of operation for draft or tidal constraints
Time of the year
Tank size, capacities and available specialist equipment required
Track record in the proposed operation
Any specialist equipment supplied is maintained and calibrated
DP vessels to be fully compliant to IMCA guidelines
Jack-up vessels to be compliant to GL-Noble Denton approvals
14
14
15

Installation and de-commissioning services
Whatever the wind farm installation
and decommissioning requirements,
GL Garrad Hassan has the experience
Together, GL Garrad Hassan and,
GL Group division, GL Noble Denton
offer a comprehensive service, evaluating
and optimising all the marine lifting and
construction activities that are required
during the lifetime of an offshore wind
farm project. Whatever the wind farm
installation and de-commissioning
requirements, GL Garrad Hassan has
experience of the latest vessels, plant, port
and industry-development plans, and civil
construction techniques so that clients can
be confident of high-quality advice that is
tailored to meet their specific needs.
Lift-vessel selection – GL Garrad Hassan holds a world-wide database
of 600+ vessels capable of lifting in excess of 100 tonnes
Site-specific installation technique optimisation
Detailed project planning and end-to-end installation programme
analysis with Monte-Carlo simulation
Package management
Mobilisation port reviews
Lift studies for monopole, tripod, TP WTG, installation
Cable installation methods review
Cable installation engineering
Cable installation management
Site assessments for jack-ups
Risk management
Mooring studies
Jack-up site assessments
Transportation engineering
Pile driveability studies
Generation of installation procedures and method statements
Chairing risk assessments
Structural design
Vessel DP capability assessments
Vessel and project equipment suitability surveys
Vessel competence audits
Contractor audits
Logistics studies
Critical path schedule analyses
Construction management
HSE reviews
CDM and principal contractor management
Marine operations management
Case Study: North Hoyle Wind Farm
Client: Npower Renewables
GL Garrad Hassan carried out the project management and technical
evaluation work for the decommissioning of the North Hoyle met
mast. The met mast was successfully returned to shore and recycled
in the summer of 2009.
16
17

Marine warranty services
Operations and maintenance (O&M)
Marine warranty services delivered
by respected technical experts
This is to ensure that marine best practice
is followed, maritime equipment is
suitable and compliant, and that marine
construction/installation procedures are
adequate for approval of insurance during
critical operations (for example loadouts
and installation of large assets). Without
marine warranty survey approval, the marine
insurance may be withheld or the liability
reduced by the underwriters.
GL Group division, GL Noble Denton was
instrumental in defining the form and role
of the marine warranty surveyor and is
considered an authority on the provision
of these services. It has developed a set
of worldwide renowned guidelines which
are now the industry standard for marine
projects. These guidelines, which form the
basis of its approval for marine operations,
are constantly maintained by a dedicated
technical policy board to ensure they remain
up-to-date with current practices.
GL Garrad Hassan provides a marine warranty
service delivered by respected technical
experts who will aid the effective completion
of the scope by offering the following:
18
Marine warranty services are normally
engaged to give insurance underwriters
assurance that key operations are engineered
safely. This might cover lifts, loadouts,
towages and offshore installation of a
variety of structures. Additionally, a client
may wish the services of a marine warranty
surveyor (even when no insurance clause is in
force) to ensure a safe, timely and practical
completion of the project.
Marine warranty is pro-actively involved
with the wind farm industry, normally from
the earliest phase of the projects, advising
on marine operations, methodology and
marine spread, selection and assessment.
Although the use of marine warranty services
is a requirement from the project insurance
underwriters, marine warranty surveyors
work directly with the project constructors to
provide marine advisory input.
A core team of highly competent personnel
A large body of relevant engineering and
marine operations experience
Well-defined cost structures and execution
methodologies leading to competitive pricing
A sound system for the management of HSE
and quality
GL Garrad Hassan’s process allows
clients to understand O&M strategies,
costs, and risks before they get into
the field
The operational cost of wind energy can be
considered in three broad categories – the
energy revenue lost through downtime, the
variable cost of measures taken to reduce
that revenue loss, and fixed costs associated
with the operations and maintenance (O&M).
The selection of optimal approach to O&M
relies on minimising the total of the first two
of these; this is where GL Garrad Hassan’s
well-established simulation process comes
into its own – allowing clients to develop
their O&M strategy and resourcing before
they get into the field.
Reliability is key to successful offshore wind
farm operations and, as well as having the
analytical tools, GL Garrad Hassan brings
in-depth experience of actual reliability
in the field of wind turbines and critical
electrical equipment. This comes from its
work monitoring over 20GW of onshore and
offshore wind farm projects on behalf of
project owners and lenders, as well as from
its design and reliability engineering on the
wind turbines themselves.
In addition, as wind farm developments
become operational, the transportation
phase of the project continues, requiring
the transfer of personnel to and from the
field for operations and maintenance. The
vessels utilised in these operations must be
managed and maintained on an ongoing
basis. GL Group division, GL Noble Denton
utilises vessel assurance programmes that
help to accomplish this, either on behalf of,
or in association with, the client. It develops
both bespoke and standardised inspection
programmes so that clients are confident
of the continued compliance of the vessels
used, as well as their suitability for continued
operations.
19

Bladed software
Bladed is the industry standard
wind turbine design and
certification software
GL Garrad Hassan’s approach to the
calculation of wind turbine performance
and loading has been developed over the
last twenty five years. The main aim of this
development has been to produce reliable
tools for use in the design and certification of
wind turbines.
The Windows-based graphical user interface
and on-line help facility makes Bladed easy
and convenient to use. It is the industry
standard for wind turbine design calculations
and supports calculations of combined wind
and wave loading, with full aeroelastic and
hydroelastic modelling and seismic excitation.
Bladed has been validated by Germanischer
Lloyd for the calculation of wind turbine
loads for design and certification.
Bladed is used by wind turbine and
component manufacturers, certification
agencies, design consultants and research
organisations across the world. A number
of modules are available covering steady
state analysis, dynamic load simulations,
analysis of loads and energy capture, batch
processing and automated report generation,
interaction with the electrical network, and
model linearisation for control design.
Bladed is also available in an educational
version which provides a world class tool for
teaching wind turbine technology.
Case Study: OWTES – Blyth Offshore Load Measurement and Validation
Client: European Commission
GL Garrad Hassan undertook this ground-breaking project in which we instrumented
the first wind turbine to be installed in UK waters, indeed the first to be installed in
an aggressive North Sea environment. Those measurements fed into the validation
of the offshore wind load analysis module in Bladed.
This project was crucial in capturing complex interaction between hydrodynamic
loading and the aero-elastic response of a wind turbine, allowing the support
structure of offshore wind turbines to be safely optimised.
20 21

Wind speed and energy analysis
Due diligence
22
“All aspects of wind farm projects can
be managed – except the wind resource.
You can understand the resource but
you surely can’t change it.”
When project developers, owners and
investors want to understand their wind
resource, they turn to GL Garrad Hassan.
Its experts have assessed over 100GW of
wind projects and much of the capacity now
operating worldwide. This work is supported
by a substantial ongoing internal research
and development effort. Offshore projects
have specific challenges around macro-scale
modelling, from sparse measurement stations
to understanding wind flow and wake effects
in and between the planned projects.
GL Garrad Hassan has been at the forefront
of developing and applying the tools to serve
the industry, including:
Wind mapping through innovative
combinations of meso-scale and satellite
imagery
Large wind farm array model option
developed for its WindFarmer – wind farm
design software code
Case Study: Sheringham Shoal Offshore Wind
Farm – Equity
Client: Statkraft
GL Garrad Hassan recently completed an independent technical assessment for
Statkraft, analysing its investment in the UK’s Sheringham Shoal Offshore Wind
Farm. Working to a tight programme, GL Garrad Hassan’s experts provided an
independent risk assessment looking at costs, energy yield, operational issues,
general programme and technical risks.
The Sheringham Shoal project, jointly-owned by Statoil-Hydro and Statkraft,
will be Britain’s fourth largest Offshore Wind Farm and will be located 20km
north of the Norfolk costal town, Sheringham. Consisting of 88 wind turbines
over 35 square kilometres, this will, on completion equate to 1.1TWh of
electricity going into the National Grid every year.
The company has a broad
perspective which underpins
its due diligence expertise
The foundation of GL Garrad Hassan’s due
diligence expertise is the extensive wind
work that its engineers have completed
over the last twenty five years. This provides
the company with a broad perspective as a
result of having to deal with a wide range of
challenges across all the major national wind
markets of the world. GL Garrad Hassan has
undertaken more wind energy due diligence
studies than any other company. It has no
equity interest in any project and here its
independence is assured.
GL Garrad Hassan’s offshore experts provide
full technical support in assessment of the
viability of an opportunity. They will also
advise clients where the key residual risks
lie so that they can feel confident about a
decision to proceed, or indeed pass.
As the world’s largest renewable energy
consultancy, GL Garrad Hassan understands
how crucial time frames are and it is used to
delivering to very demanding deadlines.
GL Garrad Hassan is able to carry our due
diligence for:
Wind farm acquisitions
Vessel acquisitions or long-term charters
Investment decisions for turbine technology
Due diligence to underpin project finance
solutions
23

Structural design and analysis
A comprehensive structural design
and analysis service covering the entire
turbine life cycle, from conceptual
design through to operation
GL Garrad Hassan delivers specialist structural
design and analysis services to offshore
wind projects in the planning, procurement,
construction and operation stages. Its
experts can select from a range of robust
and efficient in-house design methodologies
that are tailored to the different stages of
a renewables project; they can also utilise a
full range of analysis tools including offshore
industry standard structural analysis software
(for example SACS, ASAS), finite element
analysis software (for example ABAQUS) and
GL Garrad Hassan’s own renewables industrystandard
’Bladed’ software.
Left: Finite element modelling
Photographs: Analysis and repair solutions
Some of the specialist structural design
and analysis services that GL Garrad Hassan offers are:
Geotechnical interpretation and development of design soil profiles
Turbine-specific support structure concept evaluation
Offshore substation superstructure and substructure design
Viability and economic assessment of novel structural systems
Preliminary structural design
Geophysical survey scoping and design
Geotechnical survey scoping and interpretation
Pile driveability / drilling assessment
Secondary steelwork design
Structure weight and cost estimation
Design basis and functional design specifications
Site data studies (metocean and wind climate)
CAD structural drawings
Technical reviews and support services
Structures works package management
Due diligence
Design verification
Fabrication inspections
Offshore structural inspections
Re-analysis of in-place structures
24 25

Short-term forecasting
GL Garrad Hassan has global wind
energy forecasting expertise going
back nearly three decades
As wind-generated electricity increasingly
impacts on many countries’ grids, its
fluctuating nature makes a uniform approach
to managing energy from all sources
crucial. Accurate short-term forecasting of
wind power can help to achieve this goal.
Independent system operators who have
to manage supply and demand on a grid
system can avoid many of the balancing
issues if accurate forecasts of wind output
are available. Anybody trading in wind
energy can negotiate a better price if they
have precise information about the volume
they have to sell at any particular time.
A study published in 2006 revealed the
potential benefit of using GL Garrad Hassan’s
forecasting service to be a 10/MWh increase
in the traded value of wind energy.
With global wind energy forecasting
expertise and experience going back nearly
three decades, GL Garrad Hassan now
operates services for a range of clients, with
over 33GW of wind, in countries all around
the world. Utilities, energy traders, wind
farm operators and ISOs rely on this highly
accurate and reliable forecasting service with
its operational availability of 99.9%.
Currently GL Garrad Hassan is forecasting
for a number of offshore wind farms with a
total installed capacity of over 300MW, and
has had experience of offshore forecasting
since 2005. In addition to forecasts of wind
farm production, GL Garrad Hassan is able
to provide site-specific forecasts of wave
conditions and weather warnings in order to
help optimise maintenance schedules.
26
27

Electrical design and analysis
Strategic studies
GL Garrad Hassan’s offers offshore electrical
engineering specialists. They provide services
at all stages of the development process from
early feasibility work and planning through
to design, tendering, construction and
operation; these include:
Vessel design
Outline design for costing and planning
Grid connection
Electrical design and load flow analysis
Specification and tendering
Construction and operational inspection
We have access to a range of
internationally recognised guidelines
GL Garrad Hassan has completed policy
and market reviews for many clients from
technology start-ups and site developers,
to government agencies. There are diverse
motivations for seeking an improved market
understanding but the questions which need
to be answered change little:
• How has offshore wind energy developed
in the key markets?
• How do the markets compare in
relation to regulation, legal framework,
targets and incentives and the general
governmental attitude towards the
industry?
• What has worked, and what hasn’t
worked, in the development of successful
national markets for offshore wind energy,
and how can this be used to make better
decisions in the future?
During this work GL Garrad Hassan has
perceived a need in the market place
for answers to these questions from an
independent voice close to key market
players and regulators; in response, it has
developed an Offshore Wind Energy Market
Review, documenting existing regulatory
frameworks, examining experience and
reporting on developments; the report
covers:
Market development
Targets, incentives and policy
Grid access
Planning, regulation and licensing
Through GL Group division, GL Noble Denton,
GL Garrad Hassan has access to a range of
internationally recognised guidelines for key
aspects of defining offshore vessel operations
and vessel design. GL Noble Denton has
a comprehensive suite of internationally
recognised guideline documents which are
referenced by designers who wish to achieve
marine warranty approval of the loadout,
transportation and installation of offshore
structures and installations, and the vessels
used for installation, including the jack-up
units and lift-boats which are commonly used
to install wind turbines. These guidelines
include:
Geotechnical guidance for jack-up design
Marine operations guidance
Naval architecture guidance notes
Risk guidance
Structural guidance
Approval procedures for marine operations
GL Noble Denton has contributed
significantly to the development of national
and international codes of practice for
self elevating (jack-up) units, including the
British Wind Energy Association (BWEA)
‘Guidelines for the Operation of Jack-ups
in the Marine Renewable Energy Industry’,
SNAME Technical & Research Bulletin 5-5A
‘Recommended Practice for the Site Specific
Assessment of Mobile Offshore Units’ which
is referenced by the BWEA guideline and
also ISO 19905-1 ‘Site Specific Assessment of
Mobile Offshore Units’. GL Noble Denton has
a large archive of drawings, specifications,
operating manuals and analytical models
for most of the jack-up and lift-boat designs
currently in use around the world allowing
efficient assessment of unit capability to
withstand limiting weather conditions.
Case Study: Capital cost trends and drivers
Client: British Wind Energy Association
In response to dramatic changes in industry cost drivers, the British Wind Energy
Association commissioned GL Garrad Hassan to undertake a study examining capital
cost trends and drivers for offshore wind projects under various possible scenarios.
The resultant report, published by the British Wind Energy Association in June
2009, found that the offshore wind energy sector has been hampered by both
macroeconomic forces and a supply chain shared with onshore wind.
The report went on to develop scenarios for the five-year future of the industry,
concluding that promoting supply chain confidence and support for the development
of a sector-specific supply chain, with significant indigenous content, is the key to
ensuring the success of the UK offshore wind energy sector.
Through day-to-day contact with key players in all of the major offshore wind energy
markets, GL Garrad Hassan is uniquely placed to provide such strategic analysis,
insight and advice to anybody seeking to initiate or improve their understanding of
this rapidly-growing industry.
28 29

Training courses
GL Garrad Hassan’s training
courses have been informing
renewable energy professionals
for over 20 years
The vast specialist technical and engineering
expertise retained within the company has
been honed to develop both packaged
and bespoke training courses that deliver
understanding to people at all stages of their
career. Courses are delivered by specialist
staff who are leaders in their individual fields
and, when not training, are heavily involved
in GL Garrad Hassan’s commercial consultancy
work and R&D projects.
OFFSHORE WIND ENERGY (1 day)
A one-day course for industry professionals who wish
to acquire a comprehensive overview of the subject and
have the latest technology and issues clearly explained.
Offshore wind resource, wind turbine and support
structure technology, electrical issues and administrative
processes are covered.
GH BLADED SOFTWARE TRAINING (2-5 days)
This course is designed for new users of GH Bladed.
It includes hands-on guided use of the software
complemented by tutorials on key topics of wind
turbine technology. The five-day course is normally
provided at GL Garrad Hassan’s office in Bristol, UK,
but can be provided at your facilities by prior
arrangement.
OFFSHORE WIND FARM ELECTRICAL SYSTEMS (1 day)
Drawing upon GL Garrad Hassan’s extensive
involvement in the electrical design of offshore wind
farms across Europe, this course will provide a solid
foundation to help developers and operators
understand the electrical issues for offshore wind farms.
GL Garrad Hassan’s security experts also
provide a range of courses to help clients to
meet the requirements of the International
Ship and Port Facility Security Code (ISPS)
and be prepared for any situation which
might arise.
Where relevant, GL Garrad Hassan’s training
courses are approved by UK Maritime &
Coastguard Agency (MCA) – (meeting
requirements laid down in STCW ‘78, as
amended, Regulation VI/5 and STCW Code
Section A-VI/5), TRANSEC and Marshall
Islands.
To further develop these ISPS measures and
provide ongoing support, both onshore and
offshore, GL Garrad Hassan’s security experts
also undertake activities such as:
Conducting ship security assessments and
developing ship security plans
The creation of port facility security plans
ISPS based security awareness training for
ship crew and port facility personnel
Creating and implementing security related
exercises and drills
The development of security and contingency
plans, along with supporting emergency
response procedures
COMPANY SECURITY OFFICERS’ TRAINING (4 days)
SHIP SECURITY OFFICERS’ TRAINING (3 days)
PORT FACILITY SECURITY OFFICERS’ TRAINING (3 days)
SECURITY MANAGEMENT AWARENESS (1 day)
A one-day course that introduces senior managers
to security management, focusing on offshore
construction projects. This includes the legal
requirements and implications of the International Ship
and Port Facility Security Code (ISPS), and how effective
security management complements safety and risk
management.
Undertaking security based compliance
audits
Conducting incident investigations
Supply-chain security management
arrangements
Bomb threat and search awareness training
CCTV management
Access control measures
Providing a wide range of specialist security
consultancy
GL Garrad Hassan also assesses new build
ships whilst still in their design stage, making
recommendations to designers on how they
can develop in security at the planning stage.
This negates the need for clients to meet the
additional costs of having these become an
additional expense.
30 31