IEC TS 62600-102:2016

IEC TS 62600-102 ®
Edition 1.0 2016-08
TECHNICAL
SPECIFICATION
colour
inside
Marine energy – Wave, tidal and other water current converters –
Part 102: Wave energy converter power performance assessment at a second
location using measured assessment data
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IEC TS 62600-102 ®
Edition 1.0 2016-08
TECHNICAL
SPECIFICATION
colour
inside
Marine energy – Wave, tidal and other water current converters –

Part 102: Wave energy converter power performance assessment at a second

location using measured assessment data

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.140 ISBN 978-2-8322-3530-0

– 2 – IEC TS 62600-102:2016 © IEC 2016
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references. 7
3 Symbols and units . 8
4 Sequence of work . 9
5 Limitations of this technical specification . 10
6 Description of wave energy conversion (WEC) technology . 10
7 Assess and characterize wave resource related to Location 1 and Location 2 . 10
7.1 General . 10
7.2 Ambient condition . 10
7.3 Wave resource at Location 1 and Location 2 . 10
8 WEC power capture data at Location 1 . 10
9 WEC model validation . 11
9.1 General . 11
9.2 Bin selection . 11
9.3 Error per bin. 11
9.4 MAEP error . 11
9.5 Accounting for PTO losses . 12
10 Modifications to the WEC . 12
11 Calculate capture length matrix for use at Location 2 . 13
11.1 Evaluate appropriate dimensionality of the capture length matrix at Location 2 . 13
11.2 Calculate information for each bin of the capture length matrix . 13
12 Quality assurance for cells based on measurements at Location 1 . 14
13 Complement capture length matrix to cover range of conditions at Location 2 . 14
13.1 Capture length matrix complementation requirement . 14
13.2 Interpolation or extrapolation of the capture length matrix . 14
13.3 Numerical model . 14
13.4 Use of physical model . 14
14 Calculate MAEP at Location 2 using complemented capture length matrix and
Location 2 resource data . 15
15 Assessment of confidence . 15
Annex A (informative) Example analysis . 17
A.1 General . 17
A.2 Description of the WEC technology (Clause 6) . 17
A.3 Assess and characterize wave resource related to Location 1 and Location
2 (Clause 7) . 18
A.4 Assess and characterize wave resource at Location 1 . 19
A.5 Assess and characterize wave resource at Location 2 . 20
A.6 WEC power capture data at Location 1 (Clause 8) . 21
A.7 WEC model validation (Clause 9) . 22
A.8 Calculate capture length matrix for use at Location 2 (Clause 11) . 24
A.8.1 Assess the appropriate dimensionality of the capture length matrix at
Location 2 (11.1) . 24
A.8.2 Calculate information for each bin of the capture length matrix (11.2) . 24

A.9 Perform quality assurance on capture length matrix for application at
Location 2 (Clause 12) . 24
A.10 Complement capture length matrix to cover range of conditions at Location 2
(Clause 13) . 25
A.11 Calculate MAEP at Location 2 using complemented capture length matrix
and Location 2 resource data (Clause 14) . 26
A.12 Assessment of confidence . 26
Annex B (informative) Power take off efficiency . 27
B.1 General . 27
B.2 Absorbed power . 27
B.3 Power take off efficiency . 27
Annex C (informative) Example calculation of PTO efficiency . 29
Annex D (informative) Sources of uncertainty for MAEP at Location 2 . 31
D.1 Comparisons between Location 1 and Location 2 . 31
D.2 Bathymetry and water depth . 31
D.3 Current . 31
D.4 Wave spectrum . 32
D.5 Wave direction and short-crested waves . 32
D.6 Wave converter modifications . 32
Bibliography . 33

Figure A.1 – The Wavestar prototype (diameter of each float is 5 m) . 17
Figure A.2 – Map showing Location 1 Hanstholm and Location 2 Fjatring . 18
Figure A.3 – Location 1 Wave Energy Flux Matrix, Hantsholm, Denmark (based on
measured data from Wavestar prototype Feb 2012 – Jan 2013) . 20
Figure A.4 – Location 2 Wave Energy Flux Matrix, Buoy 2031 (Fjaltring, Denmark) . 21
Figure A.5 – Wavestar prototype capture length matrix Location 1 . 22
Figure A.6 – Numerically modelled electrical power matrix, adapted from [2] . 23
Figure A.7 – Model validation indicating percent difference in capture length between
observations and model (model-observations) . 24
Figure A.8 – Wavestar prototype capture length matrix for Loaction 2. Fjaltring,
Denmark . 25
Figure B.1 – Overview of the PTO system used in the prototype of Wavestar . 27
Figure C.1 – PTO efficiency matrix for the Wavestar prototype at Location 1,
Hantsholm, Denmark . 30

Table 1 – Symbols and units . 8
Table A.1 – Locations 1 and 2, basic information . 18
Table A.2 – Table of MAEP contributions. 26
Table C.1 – Example records including wave conditions, absorbed and electrical
power and resultant PTO efficiency . 29

– 4 – IEC TS 62600-102:2016 © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MARINE ENERGY – WAVE, TIDAL AND
OTHER WATER CURRENT CONVERTERS –

Part 102: Wave energy converter power performance assessment
at a second location using measured assessment data

FOREWORD
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The main task of IEC technical committees is to prepare International Standards. In
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• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC TS 62600-102, which is a technical specification, has been prepared by IEC technical
committee 114: Marine energy – Wave, tidal and other water current converters.

The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
114/179/DTS 114/187A/RVC
Full information on the voting for the approval of this technical specification can be found in
the report on voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 62600 series, published under the general title Marine energy –
Wave, tidal and other water current converters, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 6 – IEC TS 62600-102:2016 © IEC 2016
INTRODUCTION
This technical specification, IEC TS 62600-102, provides a uniform methodology for
estimating and reporting the performance of a Wave Energy Converter (WEC) at a
prospective new deployment location. The performance estimation methodology is based
primarily on observations and measurement results gathered during field deployment of the
WEC at a primary location (as per IEC TS 62600-100) with different metocean conditions
compared to the prospective new location. Further, it is possible that the WEC design will
incorporate changes to accommodate the new site conditions. To assess the performance,
inclusion of additional information based on validated numerical and physical models is
specified. In this technical specification the completed field deployment location is referred to
as “Location 1” and the prospective deployment location is referred to as “Location 2.”
The specification provides a methodology for arriving at the mean annual energy production
(MAEP) for the WEC at Location 2. Other Technical Specifications in this series
(IEC TS 62600) are drawn upon to provide the wave resource and WEC performance
information needed to enable this analysis. The methodology involves:
• assessment of the wave resource at Location 1 and Location 2,
• characterization of the WEC performance at Location 1,
• assessment and compensation for the impact of discrepancies in the metocean conditions
between Location 1 and Location 2 on the WEC performance characterization,
• assessment of the impact of changes to the WEC configuration between Location 1 and
Location 2 on the WEC performance characterization,
• complementing the performance observations from Location 1 with fit, experimental or
numerically modelled data,
• estimating the MAEP based on the composite performance characterization of the WEC.
This technical specification provides:
a) guidance on the use of observations from Location 1,
b) methods for assessing and reporting the validity of numerical and physical models,
c) limits on the permissible changes to the WEC between Locations 1 and 2,
d) limits on the use of data fitting techniques, and
e) requirements for reporting.
The wave power industry is at an early stage of development. There is little practical
experience with field-scale WECs deployment. Because of this, the present document is
designated as a technical specification and will be subject to change as more data is collected
and experience with wave energy converters develops. This Technical Specification, when
used in conjunction with other Technical Specifications in this series (IEC TS 62600), is
intended for several types of users, including, but not limited to, the following:
• Project developers – income, return on investment
• Device developers – performance of device
• Utilities/investors – reliability/predictability of supply, return on investment
• Policy-makers/Planners – usage of seascape, optimisation of resource, power supply
issues
• Consultants to produce resource data/due diligence – compatible/readable data format

MARINE ENERGY – WAVE, TIDAL AND
OTHER WATER CURRENT CONVERTERS –

Part 102: Wave energy converter power performance assessment
at a second location using measured assessment data

1 Scope
Wave Energy Converters (WEC) need to be designed to operate efficiently at different
locations. Systematic methods should be used to evaluate the power performance of a WEC
at a second location (hereinafter Location 2) based on power performance assessment at a
first location (hereinafter Location 1). The degree of similarity of the measured WEC (WEC 1)
and the metocean conditions at Location 1 to the secondary WEC (WEC 2) at Location 2
determine the methodology and the applicability of this technical specification.
This part of IEC 62600, which is a Technical Specification, describes the required methods
and the required conditions to determine the power performance of the WEC 2 in Location 2,
possibly at a different scale and with configuration changes to accommodate the new site
conditions, in all cases based on measured power performance of WEC 1 in Location 1. This
technical specification allows for assessment at Location 1 or Location 2 based on
limited/incomplete data material, as long as this is accompanied by a validated numerical
model or physical model and assessment of the uncertainty involved. Another key element is
transparency in the assessment.
This technical specification includes:
a) Specification of data requirements needed from the original measurements at Location 1
including an assessment of the uncertainty involved (if based on limited/incomplete data
material) in addition to those specified in IEC TS 62600-100 and IEC TS 62600-101.
b) Limitation on the changes that are allowed to the WEC and the specification of the
location.
c) Wave data required at Location 2, as a minimum the requirements found in IEC
TS 62600-101.
d) Development of the power matrix at Location 2.
e) Validation of the power matrix at Location 2.
f) Assessment of uncertainties in the derived performance parameters at Location 2.
g) Requirements for the allowable power performance transfer by geometric, kinematic and
dynamic similarity.
h) Requirements for the allowable incorporation of additional empirical model data.
i) Requirements for the allowable incorporation of additional numerical model data.
The technical specification does not cover the following items:
j) The original data measurement at Location 1 (see IEC TS 62600-100).
k) Environmental concerns.
l) Operation and maintenance.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition

– 8 – IEC TS 62600-102:2016 © IEC 2016
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
IEC TS 62600-1, Marine energy – Wave, tidal and other water current converters – Part 1:
Terminology
IEC TS 62600-100, Marine energy – Wave, tidal and other water current converters –
Part 100: Electricity producing wave energy converters – Power performance assessment
IEC TS 62600-101:2015, Marine energy – Wave, tidal and other water current converters –
Part 101: Wave energy resource assessment and characterization
International Towing Tank Conference (ITTC), Recommended Guidelines 7.5-02-07-03.7,
Wave Energy Converter Model Test Experiments
3 Symbols and units
For the purposes of this technical specification, the symbols and units listed in Table 1 apply.
The terms and definitions are in accordance with IEC TS 62600-1.
– Symbols and units
Table 1
Symbol Definition Units
C
Group velocity m/s
g
Direction of maximum directionally resolved wave
θ deg
Jmax
power
f Frequency Hz
f Frequency at component i Hz
i
h
Water depth m
H Spectral estimate of significant wave height m

m0
H Significant wave height m
s
J
Omnidirectional measured wave power W/m
J Omnidirectional measured wave power per bin W/m

i
Average wave power W/m
J
Minimum wave power W/m
∧ J
Maximum wave power W/m
∨ J
L
Capture length m
L Capture length per bin m
i
Average capture length m
L
Minimum capture length m
∧ L
Maximum capture length m
∨ L
MAEP Mean Annual Energy Production
W⋅h
n Number of records -
N Number of bins -
P Measured power output W
P Measured power output per bin W

i
P Hydraulic power input W
h
Symbol Definition Units
m
S Spectral density
Hz
m
S(f) Spectral density as function of frequency
Hz
Directional spectrum as a function of frequency and
m
direction
S(f, θ)
Hz⋅ rad
S( f )⋅ G(θ, f )
m
S Spectral density at frequency component i
i
Hz
T Energy period s
e
f Frequency spacing Hz
i
θ Wave direction Deg
P Absorbed power W
abs
P Electrical power output W
e
P Power loss (dissipated) in the PTO W
pto
η Power take off efficiency -
pto
ρ Density kg/m
σ Standard deviation -
4 Sequence of work
The sequence of the work is outlined below:
a) Describe the WEC technology.
b) Assess and characterize wave resource at Location 1 and Location 2 using IEC TS 62600-
101.
c) Calculate the capture length matrix from WEC power capture data at Location 1 using IEC
TS 62600-100.
d) Evaluate the appropriate dimensionality of the capture length matrix from Location 1 for
Location 2 and complement the capture length matrix from Location 1 to cover the range
of metocean conditions at Location 2 using numerical or experimental data.
e) Validate the model against measured data from Location 1.
f) Specify changes to the WEC to accommodate the new metocean conditions.
g) Evaluate the impact of changes to the capture length of each bin using validated
numerical model data incorporating the parameters in question. If the capture length in a
bin is changed by more than 10 % it shall be filled using physical or numerical modelled
data.
h) Perform quality assurance on capture length matrix for application at Location 2.
i) Calculate MAEP at Location 2 using the complemented capture length matrix and
Location 2 resource data.
j) Report separately the MAEP at Location 2 contributed by the cells of the power matrix that
are based on either:
1) measured data at Location 1, or
2) interpolation or extrapolation from measured data, or
3) modelled data.
k) Estimate the uncertainty related to the MAEP calculated at Location 2.

– 10 – IEC TS 62600-102:2016 © IEC 2016
Annex A provides a detailed illustration of the concepts and calculations in each step in the
sequence of work.
5 Limitations of this technical specification
This specification allows for changes to the WEC when moved from Location 1 to Location 2
in order to accommodate the new metocean conditions. Changes to the WEC should be
clearly specified and may include: dimensions, geometry, power take off system, control logic
and moorings system. Allowable changes and procedures are specified in Clause 10.
6 Description of wave energy conversion (WEC) technology
The wave energy converter WEC 1 deployed at Location 1 and the WEC 2 to be deployed at
Location 2 shall both be described in terms of:
• Operational principle.
• Geometry and dimensions.
• Mass properties.
• PTO system.
• Mooring arrangement.
7 Assess and characterize wave resource related to Location 1 and Location 2
7.1 General
Similar to 6.1 of IEC TS 62600-101:2015, a site description shall be prepared for each of the
WEC locations under consideration.
7.2 Ambient condition
For each location this description should include a map or chart, geographic coordinates, the
water depth as well as general description of the following:
• The shoreline geography and bathymetry.
• The prevailing wave and wind conditions.
• Typical tidal range and currents.
7.3 Wave resource at Location 1 and Location 2
A description of the wave resource at Location 1 and Location 2 shall be provided and
include:
• Directional rose plots.
• Scatter tables and plots.
• Exceedance and persistence.
• Joint probability analysis.
8 WEC power capture data at Location 1
An analysis of the WEC electrical power performance at Location 1 should be undertaken
using the methodologies stated in IEC TS 62600-100. The measured WEC power production
records along with the concurrent wave measurements should be used to calculate and report
the following:
• Electrical power matrix.
• Capture length matrix.
• Maximum of capture length matrix.
• Minimum of capture length matrix.
• Standard deviation capture length matrix.
NOTE Other potentially useful but not strictly required deliverables of the IEC TS 62600-100 analysis are
absorbed power and PTO efficiency matrices.
The measured WEC power production records along with the concurrent wave measurements
shall be preserved for further analyses within this specification.
9 WEC model validation
9.1 General
A numerical and/or physical model may be required to satisfy the requirements of this
specification. The validity of each model shall be assessed by comparison of the results with
observations from WEC 1 at Location 1. Specific requirements for the comparison are given in
the following subclauses.
NOTE These are the minimum requirements for communication of the level of validity of the physical and/or
numerical models. At this stage, it is left to the users and analysts of the documentation to judge the validity of the
physical/numerical model from the difference between modelled and observed performance.
9.2 Bin selection
At minimum, 10 bins of the capture length matrix, covering the range of occurrences at
Location 1, shall be selected for validation. The bin selection process shall be documented
and justified. For each of the selected bins, a minimum of three model runs shall be
performed using different random wave seeds. The number of model runs used in each
validation bin shall be documented.
Each model run shall use as input either: observed wave conditions from Location 1, or wave
conditions representative of the capture length matrix bin being simulated. The wave
conditions used in each model run shall be documented. Where representative wave
conditions are used the methods for determining those representative conditions shall be
documented and justified.
9.3 Error per bin
The percent difference between the mean modelled capture length, L , and mean
model,i
th
observed capture length, , in the i bin shall be calculated and clearly presented for
L
measured,i
all bins as follows.
L=100⋅−(LL ) L
(1)
err,i model,i measured,i measured,i
9.4 MAEP error
The percent error between the modelled MAEP and the measured MAEP shall be presented
using formula (2).
MAEP = 100⋅(MAEP – MAEP )/MAEP (2)
err model measured measured
NOTE MAEP is representative of only the portion of the MAEP contributed by those bins used in the validation
err
procedure.
– 12 – IEC TS 62600-102:2016 © IEC 2016
The modelled and measured MAEP quantities may be established as per IEC TS 62600-100:
MAEP= T L J f (3)
∑
i ii
i
where
T is the average number of hours per year (8 766),
L is the bin-average observed capture length,
J is the wave power flux,
f is the frequency of occurrence, and
th
i is the index of the i bin.
In this case i refers to only those bins used for validation.
9.5 Accounting for PTO losses
The model shall account for power conversion losses within the power take off system. Where
a physical scale model is used, the power performance shall be quantified in terms of
absorbed power. Then, following the appropriate scaling of absorbed power and wave
parameters, the power take off efficiency shall be applied to estimate electrical power and
calculate capture length values. Refer to Annex B for methodology to quantify and apply PTO
efficiency.
10 Modifications to the WEC
Modifications to the WEC and ancillary hardware are permitted. The capture length data from
deployment of WEC1 at Location 1 can only be used to characterize WEC2 including
modifications if it can be shown that these modifications impact on the power performance of
the device by 10 % or less per bin. If the modifications exceed this limit in a bin it shall be
filled using validated numerical methods as outlined in Clause 9 and Clause 13. Modifications
may be required to the WEC to adapt to Location 2, and shall be documented as follows:
• Description of the change.
• Purpose of the change.
• Impact on the performance of the WEC on a bin-by-bin basis.
Modifications to the WEC cannot be made without a validated model as described in
Clause 9. The validated model shall be adapted to accommodate the proposed modification to
the WEC. The method(s) used for accommodating the modifications to the WEC in the
numerical model shall be documented. Changes to the WEC can include, but are not limited
to, the following:
• WEC dimensional geometry changes.
• PTO component design and control law.
• Ancillary hardware (mooring system, power cable connection, WEC hardware for
deployment, etc.).
Each bin of the capture length matrix, covering the range of occurrences at Location 1, shall
be selected to assess the impact of the WEC modification. For each of the bins, a minimum of
three model runs using different random wave seeds shall be performed for the modified
WEC.
The difference between the mean capture length of the unmodified WEC 1 and mean capture
length of the modified WEC 2 in each bin shall be presented and evaluated. For the capture

length data from deployment of WEC 1 at Location 1 to be used to characterize WEC 2, the
absolute difference between the mean capture length values shall be no greater than 10 %
per bin. Any bins that have greater than 10 % difference shall be populated using modelled
data as outlined in Clause 13.
11 Calculate capture length matrix for use at Location 2
11.1 Evaluate appropriate dimensionality of the capture length matrix at Location 2
Minimum dimensions of the capture length matrix are specified in IEC TS 62600-100 as
and T . IEC TS 62600-100 advises that the dimensionality of the capture length
including H
m0 e
matrix should be expanded where possible to reduce the variance of capture length within
each bin. In many cases the range of occurrences of metocean parameters at Location 2 will
differ from Location 1. Estimation of performance at Location 2, requires that the appropriate
dimensionality of the capture length matrix shall be re-evaluated. At minimum, the sensitivity
of the WEC shall be investigated to the following parameters:
• Water depth.
• Wave direction.
• Spectral shape and directional spreading.
• Water current.
• Tidal range.
It may be necessary to expand the dimensionality of the capture length matrices to account
for any parameters (additional to H and T ) found to have a major effect on WEC power
m0 e
performance. Each of the parameters listed above shall be considered in turn. It shall be
shown that inclusion of the parameter in question impacts the calculation of MAEP at Location
2 by less than 10 %, otherwise the dimensionality of the capture length matrix shall be
increased to account for that parameter.
As an example, suppose a WEC is directionally sensitive and that the wave direction is
relatively constant at Location 1. In this case it may still be possible to neglect the
directionality dimension when constructing the capture length matrix and calculating MAEP at
Location 1. However, if the wave directionality is more variable at Location 2 it may be
necessary to include directionality in the capture length matrix to accurately estimate the
MAEP at Location 2.
To test if inclusion of directionality is necessary in this demonstration case, both the 2D (H -
m0
T ) and 3D (H -T -X) capture length matrix shall be constructed to cover the range of wave
e m0 e
conditions observed at Location 2 (where X is a placeholder for the parameter currently under
study). The complementing procedure of Clause 13 shall be used to fill bins in the capture
length matrix for which there are no supporting observations. The MAEP shall be calculated
using both the 2D and 3D capture length matrix. If the difference between the two MAEP
calculations is greater than 10 %, then the additional dimension shall be included in the
capture length matrix at Location 2.
NOTE The 10 % difference limit on MAEP will properly be revised in the future as more experience is gained;
currently it is the same magnitude as the variability in the annual average wave energy flux.
11.2 Calculate information for each bin of the capture length matrix
Using the performance data from Location 1 the average capture length matrix shall be
constructed as outlined in IEC TS 62600-100, using the appropriate dimensionality as
identified in 11.1. The following shall be calculated for each bin in the matrix:
• The average capture length.
• The maximum capture length of all the data records in the bin.
• The minimum capture length of all the data records in the bin.

– 14 – IEC TS 62600-102:2016 © IEC 2016
• The standard deviation of the capture length of all the data records in the bin.
• The number of data records in the bin.
NOTE See Annex A for a detailed example.
12 Quality assurance for cells based on measurements at Location 1
Capture length matrix for use at Location 2 shall be quality checked and empty bins shall be
labelled “undefined”. Bins of the capture length matrix shall be labelled “underpopulated” if:
• data is known to be inaccurate;
• there are less than 3 data records in the bin.
The quality assurance methodology shall be documented and justified
NOTE Refer to Annex A for detailed example.
13 Complement capture length matrix to cover range of conditions at Location 2
13.1 Capture length matrix complementation requirement
The capture length matrix may be complemented to estimate the value in underpopulated and
undefined (empty) bins. The minimum number of data records in each bin of the capture
length matrix is specified in Clause 12. The capture length matrix may be complemented by:
a) Data fitting (interpolation or extrapolation).
b) Model fitting (numerical or physical).
Bins with complemented data shall be clearly identified. Where a model is used to
complement the capture length matrix, it shall be validated as per Clause 9. Where several
methods are available to complement a bin, the method with the least uncertainty should be
used.
NOTE See Annex A for an example.
13.2 Interpolation or extrapolation of the capture length matrix
Data fitting using interpolation or extrapolation may be used to populate undefined bins in the
capture length matrix. Bins populated using data fitting shall be labelled. The data fit shall be
computed based on the values of observed adjoining bins. Bin populated using
complementation shall not be used to compute the data fit.
NOTE 1 "Adjacent bins" refers to bins which share a cell side or corner.
NOTE 2 See Annex A for detailed example.
13.3 Numerical model
A numerical model may be used to calculate the capture length of the WEC in any
underpopulated, undefined bin of the capture length matrix, including those where
performance of WEC 2 differs by more than 10 % from WEC 1. The numerical model can be
validated using the performance data collected at Location 1 as per Clause 9.
The shape of the wave spectra used in each run should be representative of the range of
spectral shapes observed within the bin.
13.4 Use of physical model
A physical model may be used to estimate the absorbed power of the WEC in any
underpopulated and undefined bin of the capture length matrix. The physical model testing

shall be based on International Towing Tank Conference (ITTC) Recommended Guidelines
7.5-02-07-03.7.
The physical model shall represent the actual WEC tested at Location 2 according to Froude’s
law of similitude. The shape of the wave spectra used in each sea state of the physical test
should be representative of the range of spectral shapes observed within the bins of the
scatter diagrams at Location 1 and Location 2.
The absorbed power observed during the physical model tests shall be scaled to represent
WEC2 to be deployed Location 2. To estimate electrical power output requires
characterization of the WEC power take off (PTO) system.
The efficiency of the PTO system shall be characterized and reported (see Annex B). The
efficiency characterization may be based on observations from WEC operation at Location 1,
laboratory tests or a validated numerical model. The method for characterizing shall be
documented and justified.
The absorbed power observed during physical model testing is multiplied by the PTO
efficiency to estimate electrical power, which can in turn be used to calculate capture length.
The combined result of physical model and PTO characterization shall be validated using the
performance data collected at Location 1 as per Clause 9.
14 Calculate MAEP at Location 2 using complemented capture length matrix
and Location 2 resource data
Using the performance matrix (Clause 13) and the Location 2 wave resource data (7.3) the
MAEP shall be calculated using either the standard or alternative methods described in IEC
TS 62600-100.
Separate MAEP contributions shall be reported for bins of the capture length matrix which
are:
• Measured bins: calculated from performance measured at Location 1 as per
IEC TS 62600-100 and quality assured as per Clause 12 in this specification.
• Interpolated or extrapolated bins: as per 13.2.
• Modelled bins: numerically (13.3) or physically (13.4).
The contribution of each of the above categories of bins shall be reported both as an absolute
energy value an
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