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Construction monitoring and risk management –
Wind and PV
Richard Doyle, Managing Director,
3E Renewable Energy Services, South Africa
3E history and activities
Founded in 1999
Spin-off of imec, nanoelectronics
and PV research centre
Currently employ 120 experts, 18
nationalities
Projects in over 30 countries, 5
continents
Offices in Brussels, Toulouse,
Beijing, Istanbul, Milan and Cape
Town
3E Clients
Services over project lifecycle
Technical
advisory
Owner’s
engineering
Performance
optimisation
Due diligence
Software for renewable energy portfolio
operation
Higher availability | Lower maintenance costs | Less time spent on admin
Independent performance
analysis for all portfolio
Alarm and intervention
management
Reporting and data analysis
Measurement campaign
follow-up
Short-term forecasting
1000 parks, 1000,000 components
Construction is the most risky phase of
the wind and PV project lifecycle
Operation Construction Development Contracting Project
lifecycle
Costs
Risk
• Low % of total
project costs
• First
commitments
and payments
• Payments made
for equipment/
contractors
• Largest % of total
project costs
• Medium % of total
project costs
• Risks generally
well mitigated
through technical
advisory
• First liabilities
• Schedule
sensitive to
unforeseen events
• Possible snowball
effect on delays
and costs
• Strong warranties
from OEM in first
5-10 years,
• Insurance and
guarantees on
production
Multiple players with different
objectives and incentives
• Owner(s) - Developers and Sponsors
• Lenders
• Contractor (EPC) – Responsible for project delivery
• Sub-contractor – responsible for a particular task
• Owner’s Engineer – monitoring construction with
duty to owner
• Lender’s Technical advisor - monitoring construction
with duty to bank/lenders
• Independent Engineer - monitoring construction with
duty to utility and developer
• Legal and Financial Advisors – guiding bank/lenders
on legal and financial aspects
Construction phase
~ 2- 3 weeks
Project specifications
definition EPC contract negotiations
Construction and Grid connection
Work acceptance by
ESKOM Operation
VVVV
VV
Technical due diligence
Financial close
Commissioning /
provisional acceptance tests
Facility completion/COD
~12 months
~24 months
VVVV
Project Milestones: the rush for gold
Project milestones such as foundation completion,
turbine/module delivery and commissioning trigger payments
of a % of the contract value.
However
• Project milestones and criteria for acceptance of Works often not
clearly defined by contract
• Claims for milestone completion are often not fully backed-up by
adequate certificates or sign-offs and cannot be accepted by LTA
• Contractors tend to claim milestone completion and walk away
• Contractors invoice for non-contractual milestones (due to lack of
contract-related knowledge)
• There is sometimes no or limited incentive to force contractor to finish
the work and fix snags
• Turbine/Module tests on completion are often overlooked
The need for independent
technical advisory services Independent technical guidance & construction monitoring
can reduce risk:
Identify issues faster and communicate them objectively to owners
Identify full completion of proper milestones
Scope of work should especially cover:
Contractor approval
Design document approval
Work progress monitoring
Drawdown approval
Quality management program verification
Factory Inspections
Wind turbine / PV Plant take over approval
Facility take over approval
Managing project specifications
throughout wind project construction
can be difficult Project specs processed by many
departments in EPC → delays and complex
changes
Lengthy, complex contracts often with
technical details in appendices → these are
sometimes omitted or poorly distributed
No track-record of RE construction in RSA
Many subcontractors for turnkey projects with
little on site supervision from manufacturer
Commissioning team usually not involved
from start, intervene after very long chain of
people/services
Wind project construction risks
Earthworks
Civil
Logistics
Structures
Electrical
Grid connection
Commissioning / Acceptance
Operation
Crucial step to ensure
proper functioning of plant
Health and safety risks –
to be carefully assessed
Many issues observed
Not always straightforward
Grid compliance aspects
require careful check
Large country with roads
of non-uniform quality
Not such an issue in
Europe but environmental
and fossil etc issues in SA
SAWEA and Logistics
• Green Cape raises logistical concerns mid 2011
• SAWEA took over logistics concerns
• Working group formalised in June 2012
• Meetings with authorities, developers and hauliers
• No one willing to share info (except with an
independent party) – SAWEA task group formed
• NDA drafted and sent to all BW1 developers
• 4 NDA’s signed, 3 plans received + Eskom Sere
• Mixed response from developers/contractors/suppliers
Transport and Logistics
• Logistics not included in the RFP
(sometimes part of EIA)
• No central authority for collation of
transport plans
• Only 154 days for abnormal loads
• Multiple parties involved
• Plans linked to financial close
• Only 2 haulage companies have trailers
and cranes in country
• Transport contractors advertising not
always consistent with availability
• Contractors act as agents for other
larger contractors
Typical issues encountered in civil
engineering
19
Roads (common)
• Insufficient vertical transition curve or
incorrect bending radius for long trailers
(blades)
• Crane pad and roads on an embankment
prone to soil erosion
• Road and crane pad at different levels
Foundations (less common but do occur)
• Connection piece between foundation and
tower section does not fit rebar arrangement
• Some foundations needed to be destroyed
and rebuilt due to poor concrete quality
(concrete fails 28 day cube test)
WIND - Case study # 1
Impact
Delivery of correct
cans 2 months
later
Foundations
completed with 5
months delay
Actual COD
6 months later
than schedule
Wind plant
12 3MW
turbines
In France
Description of issue
Steel can did not fit
the rebar arrangement
Civil contractor was
able to prove its rebar
arrangement was
according to EPC
specs
EPC actually delivered
the wrong steel can
type
WIND - Case study # 2
Impact Blade had to
be replaced
Significant
costs
incurred
Project
take-over
delayed by
6 weeks
Wind plant
Turbines
In France
Issue
During blade lifting, one of 2 slings
broke loose - blade almost dropped
to the ground. 1/3 of the stud bolts
engaged in the blade-bearing
partially supported blade.
High wind for 3 days after the
incident. Blade root finally secured
from inside the hub and fully
attached 2 weeks later
However, cracks quickly developed
in blade root area
A note on Health and Safety
Over the last few years, several fatal accidents occurred
during construction of wind plants and made news headlines:
• Cefn Croes (UK): 1 employee killed in a car crash on site
(2008)
• Mostyn Port (UK): 1 employee killed by 80t tower section
dropped during an unloading operation (2011)
• Mannhagen (Germany): one blade was dropped on a crane
during a lifting operation, killing the operator (2012)
Such tragic accidents paralyse works and require thorough
investigation. Incurred delays (in Europe at least) are
generally several months.
Common issues with electrical
engineering
• Delays in grid connection with turbines
completed but standing still for months
• Substation equipment does not fit
substation, requiring new permit application
→ 2 months of delay common
• Protection relays on substation switchgear
require fine-tuning
→ downtime, since WTGs do not restart
automatically after a grid fault;
• Burial depth of cable not compliant with
specifications
→ high risk of damage
Commissioning should be key step to
eliminate remaining issues but is often
rushed • Hand-over by erection teams to commissioning
teams → commissioning always takes longer than
excepted
• Mechanical and electrical parts of commissioning
require 2 sets of skills, but are often carried out by
the same technician
• Non “essential” features (reference to magnetic
North, wind sensor alignment,..) are overlooked to
speed up commissioning .
• Turbine start-up does not fully comply with run-in
requirements to speed up tests on completion
• WTG parameters tend to be uploaded on a
general basis and site specific settings are ignored
WIND - Case study # 3
Impact
6 years after
commissioning,
luckily no claims
had yet been
raised
Project was in
breach of
building permit
for 6 years
Wind plant
6 2MW
Turbines
In France
Description of issue
Due to noise constraints, 2 WTGs
were to operate at reduced noise
mode at night
Mode was not implemented at
commissioning, in breach of building
permit requirements
Owner chose to continue unrestricted
operation of WTGs
WIND - Case study # 4
Impact
Recurrent
component
damage and
unscheduled
services
accounted for
25% of
production
loss
Wind plant
24 Turbines
In Spain
Complex terrain
requiring WTG-
specific
management
(turbine stopped
or curtailed in
specific wind
directions
/speeds)
Description of issue
Wind Sector Management (WSM)
implemented in 7 WTGs, mostly in the
Eastern direction. After 6 months, high
failure rate and severe
underproduction.
It was then discovered that reference
to Magnetic North had not been
correctly calibrated in the WTG
controllers.
Detailed SCADA data analysis and
inspections revealed that WTG were
not curtailed in the Southern rather
than the Eastern direction.
WIND - Case study # 5
Impact
WTG
commissioning
delayed by 6
weeks
Take-over and
COD delayed
by 2 months
Wind plant
5 WTGs
In France
Description of issue
Commissioning crew locked rotor to service hub - did not fully unlock it before leaving nacelle
Crew restarted turbine from tower bottom with one of the two locking pins still partially engaged in the rotor locking disc
Front main bearing had to be changed - one of the locking pin housings was severely damaged
The incident damaged the high-speed shaft of the gearbox which had to be replaced
WIND - Case study # 6
Impact
Poor sensor
positioning
caused a yaw
error and an
estimated 2.7 %
of production
losses for the
first 6 months of
operation
Wind plant
Wind farm in
Belgium
Description of issue
Power curve of one WTG well
below the others despite
successful take-over
Regular power curve checks
showed consistent under-
performance
Inspection revealed that vertical
booms supporting wind sensors
were incorrectly positioned
Potential issues for SA
• Comfort around condition of the delivered turbine parts?
• Comfort that site-specific features are enabled in your
turbines?
• Ensuring that project schedule is robust enough to cope
with all uncertainties and possible delays?
• Contingency in business model to cope with delays and
potential additional works?
• Verification of compliance of the work with applicable
Laws, Permit Requirements (RoD) and grid codes
• How do you mitigate the risks related possible long delays
in grid connection works by Eskom?
• Shortage of heavy lifting equipment in the South Africa?
PV project construction risks
Technology choice
Earthworks and civil
Logistics
Structures Structures
Electrical
Grid connection
Commissioning / Acceptance
Operation
Long-term reliability
is an issue
Problems exacerbated by
repetitive structure of plants
Often poorly executed and
leading to dangerous
situations (overheating,
fires…)
Large country with roads
of non-uniform quality
Not such an issue in
Europe but environmental
and fossil etc issues in SA
Certification alone is insufficient to
ensure long-term reliability of selected
components
• Based on CE, IEC, EN, UL or other standards.
• EU: IEC61215 (xSi), IEC61646 (thin film) → design qualification and type approval.
• EU/US: IEC61730, UL1730 → safety qualification.
BASIC QUALITY
?
• Insufficient statistical data from PV plants
• Lack of data for reliability standards
• Long-term reliability not addressed in certification scope
• Many issues observed during MTA and commissioning by 3E teams
RELIABILITY
OK: Checked through certification
and compliance instruments
1 in 3 modules have significant
quality-related issues
Results of 3E Module Technical Assessments worldwide, 2010-2012
Suppliers with issues are not country-specific or technology-specific
Key issues identified
Module aspect Issues
Concept & design Incorrect certification and compliance marks.
Insufficient parameters in the module data sheet.
Compliance Certification missing, outdated or incorrect product designation.
Certification on incorrect factory site.
Modules produced and shipped with components that have not been approved by certification test.
Manufacturing aspects Discrepancies between implemented protocols vs protocols in-practice.
Insufficient quality control protocols risk in resulting in defective module.
Absence or outdated equipment calibration.
Incorrect module power rating.
Application Ambiguous installation manuals.
Unclear terms and conditions in warranty documents.
PV - Case study # 1
Impact
Mismatch losses
increasing
Module distributor
claimed snail trails
are only a visual
phenomenon and
not a defect
Legal case under
way
PV plant
3MW PV plant
In Belgium
Description of issue
Module defects (snail trails)
identified at provisional
acceptance tests on
significant portion of installed
modules
Directly related energy loss
was estimated
Snail trails caused by micro-
cracks in the module cells,
will lead to further
degradation and impact on
efficiency
Common Issues with PV project
construction Lack of contractor experience
Example: Inverters are often not
placed properly or according to
specification, to allow for sufficient
ventilation or easy access
Contractors focused on speed rather
than quality
Example: Contractor not recording
flash test results for specific plants –
serial numbers had to be manually
recorded on site by technicians for 3
weeks when assets were sold
Insufficient tests performed on site
Common Issues with PV project
construction
Use of different or wrong equipment
Example: Use of wrong bolts leading to
corrosion – all bolts (>10000) replaced
Poor cabling work
Example: No respect of bending radius
/ high cable tightness to allow thermal
dilatation →DC cabling had to be
modified by connecting extra junctions
and cable extensions to avoid cable
damage / fires
Poor electrical connections
PV - Case study # 1
Impact
Adapted construction
planning and delays
Maintenance schedule
of green zones adapted
to account for fast
growing vegetation
Changes and
adaptations to some
components to account
for unusually high
humidity levels
PV plant
9 x 1MW PV plant France Islands
Description of
issue
Projects on islands with
poor grid, inexperienced
team of large EPC/O&M
contractor
Specific micro-climate
not taken into account in
initial design and
technical specifications
Some civil/installation
works were impossible
during rainy season
PV - Case study # 2
Impact
Severe
damage to the
installation
Mounting
structures and
modules
replaced
Work had to
be redone
PV plant
4MW PV plant
In Belgium
Description of issue
At provisional acceptance tests
serious issues were identified:
Structural stability issues of
mounting structure
Non-compliant mounting of
modules in terms of manufacturer
specs: >250 modules were blown
off the rooftop
Non-compliant installation of
inverters (lack of ventilation, non-
compliant installation)
PV - Case study # 3
Impact
Municipality did not
accept revised permit
and forced the
developer and
contractor to correct
mounting structure
height at significant
cost
Technical building had
to be removed entirely
PV plant
12MW PV plant
In France
Description of issue
Construction permit
compliance was
overlooked during
construction phase
Mechanical completion
tests identified 1.5m
difference between
constructed plant and
permit
One technical building was
built in breach of building
permit
Potential issues for SA
• Comfort around the condition of the delivered modules (flash and
EL testing?
• Comfort that site-specific features are enabled in BOP?
• Ensuring that project schedule is robust enough to cope with all
uncertainties and possible delays?
• Contingency in business model to cope with delays and potential
additional works?
• Verification of compliance of the work with applicable Laws, Permit
Requirements (RoD) and grid codes
• How do you mitigate the risks related possible long delays in grid
connection works by Eskom?
• How do you identify triggers for product related insurance claims?
Thank you
For any additional information, please do not
hesitate to contact Richard Doyle:
Email: [email protected]
Phone: +27 21 300 9922
Mobile: +27 82 454 7066
www.3e.eu