IEC TS 62600-1:2011

IEC/TS 62600-1 ®
Edition 1.0 2011-12
TECHNICAL
SPECIFICATION
Marine energy – Wave, tidal and other water current converters –
Part 1: Terminology
IEC/TS 62600-1:2011(E)
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IEC/TS 62600-1 ®
Edition 1.0 2011-12
TECHNICAL
SPECIFICATION
Marine energy – Wave, tidal and other water current converters –
Part 1: Terminology
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
U
ICS 27.140 ISBN 978-2-88912-829-7

– 2 – TS 62600-1 © IEC:2011(E)

CONTENTS
FOREWORD . 3

INTRODUCTION . 5

1 Scope . 6

2 Terms and definitions . 6

Bibliography . 26

Figure 1 – Six degrees of freedom – Floating device . 9

Figure 2 – Six degrees of freedom – Submerged device . 9
Figure 3 – Wave height and wave period . 23

TS 62600-1 © IEC:2011(E) – 3 –

INTERNATIONAL ELECTROTECHNICAL COMMISSION

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

Part 1: Terminology
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

The main task of IEC technical committees is to prepare International Standards. In
exceptional circumstances, a technical committee may propose the publication of a technical
specification when
• 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 62600-1, which is a technical specification, has been prepared by IEC technical
committee 114: Marine energy – Wave, tidal and other water current converters.

– 4 – TS 62600-1 © IEC:2011(E)

The text of this technical specification is based on the following documents:

Enquiry draft Report on voting

114/65/DTS 114/76/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.

The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site 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.

TS 62600-1 © IEC:2011(E) – 5 –

INTRODUCTION
This Technical Specification has been developed as a tool for the international marine energy

community, to assist in creating clarity and understanding. The wave, tidal and water current

energy industry has recently experienced a period of rapid growth and sector development.

With this expansion, it became apparent that a glossary of terms for the sector was required.

The aim of this Technical Specification is to present clear and consistent language that will

aid the development of programs, projects, and future standards.

This Technical Specification lists the terms that the marine energy industry commonly uses. It

is an evolving document that will change as new terms and symbols are added. The

terminologies herein have been harmonized with IEC 60050 and other IEC documents as far
as possible.
– 6 – TS 62600-1 © IEC:2011(E)

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

Part 1: Terminology
1 Scope
This part of IEC 62600 defines the terms relevant to ocean and marine renewable energy. For
the purposes of this Technical Specification, sources of ocean and marine renewable energy
are taken to include wave, tidal current, and other water current energy converters.
Terms relating to conventional dam and tidal barrage, offshore wind, marine biomass, ocean
thermal and salinity gradient energy conversion are not included in the scope of this Technical
Specification.
This Technical Specification is intended to provide uniform terminology to facilitate
communication between organizations and individuals in the marine renewable energy
industry and those who interact with them.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1
added mass
extra mass associated with the additional force necessary to accelerate a body through a fluid
compared to the same acceleration in a vacuum
NOTE 1 In general, added mass is a variable that depends on the state of the unsteady motion and is not a
constant.
NOTE 2 In a viscous (real) fluid, the added mass would include kinetic energy of a fluid layer entrained by the
accelerating body.
2.2
added mass at infinity
limit of the mass corresponding to the added mass as the frequency tends to infinity

NOTE The value of added mass at infinity is normally necessary for time domain modelling of wave-body
interaction.
2.3
added mass coefficient
ratio between added mass and the mass of the water displaced by the submerged body
2.4
amplitude control
method to obtain the optimum oscillatory motion amplitude to capture a maximum of wave
energy
NOTE For a simple oscillating system, the object of amplitude control is to obtain a given oscillatory velocity
amplitude that should be related with the wave excitation force.

TS 62600-1 © IEC:2011(E) – 7 –

2.5
annual energy production (marine energy converter)

estimate of total energy production of a marine energy converter system during a one-year

period obtained by applying its power performance assessment to a prospective marine

energy resource characterization and assuming 100 % availability

NOTE Actual annual energy production is unlikely to exceed this estimate.

[IEC 60050-415:1999, 415-05-09, modified]

2.6
array (marine energy)
farm of marine energy converters arranged specifically so as to enhance energy capture
NOTE Array spacing is dictated by hydrodynamic considerations and may be very closely packed so as to
constitute a single platform or an arrangement of identical devices.
2.7
attenuator device
energy converter which is aligned parallel to the predominant direction of wave incidence
2.8
availability (marine energy converter)
ability of a marine energy conversion system to be in a state to perform a necessary function
under given conditions at a given instant of time or over a given duration, assuming that the
necessary external resources are provided
NOTE 1 For continuously running equipment availability equates to: uptime/(uptime + downtime).
NOTE 2 Where reliability is specified in Mean Time Between Failures (MTBF) and maintainability in Mean Time
To Repair (MTTR), availability also equates to: MTBF/(MTBF + MTTR).
[IEC 60050-191:1990, 191-02-05, modified]
2.9
capture area (tidal)
equal to the power captured by the hydrodynamically functional part of a TEC divided by
power per square metre of the incident tidal stream
2.10
capture length (wave)
capture width
equal to the power captured by the hydrodynamically functional part of a WEC divided by
power per metre of the incident wave field

2.11
centre of buoyancy
centroid of the submerged volume
2.12
centre of flotation
point coinciding with the centroid of the water-plane area
NOTE The water-plane area is the cross-sectional area of the floating body at mean water level in calm water.
2.13
chart datum
reference level of water, typically from a selected phase of the tide at a specific location
NOTE Different hyd
...

IEC TS 62600-1 ®
Edition 1.1 2019-03
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
colour
inside
Marine energy – Wave, tidal and other water current converters –
Part 1: Terminology
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

IEC Central Office Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
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International Standards for all electrical, electronic and related technologies.

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IEC TS 62600-1 ®
Edition 1.1 2019-03
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
colour
inside
Marine energy – Wave, tidal and other water current converters –
Part 1: Terminology
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.140 ISBN 978-2-8322-6740-0

IEC TS 62600-1 ®
Edition 1.1 2019-03
CONSOLIDATED VERSION
REDLINE VERSION
colour
inside
Marine energy – Wave, tidal and other water current converters –
Part 1: Terminology
– 2 – IEC TS 62600-1:2011+AMD1:2019 CSV
© IEC 2019
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Terms and definitions . 6
Bibliography . 27
Figure 1 – Six degrees of freedom – Floating device . 9
Figure 2 – Six degrees of freedom – Submerged device . 9
Figure 3 – Wave height and wave period . 23

© IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MARINE ENERGY –
WAVE, TIDAL AND OTHER WATER CURRENT CONVERTERS –
Part 1: Terminology
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
This consolidated version of the official IEC Standard and its amendment has been
prepared for user convenience.
IEC TS 62600-1 edition 1.1 contains the first edition (2011-12) [documents 114/65/DTS
and 114/76/RVC] and its amendment 1 (2019-03) [documents 114/289/DTS and 114/302/
RVDTS].
In this Redline version, a vertical line in the margin shows where the technical content
is modified by amendment 1. Additions are in green text, deletions are in strikethrough
red text. A separate Final version with all changes accepted is available in this
publication.
– 4 – IEC TS 62600-1:2011+AMD1:2019 CSV
© IEC 2019
The main task of IEC technical committees is to prepare International Standards. In
exceptional circumstances, a technical committee may propose the publication of a technical
specification when
• 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 62600-1, which is a technical specification, has been prepared by IEC technical
committee 114: Marine energy – Wave, tidal and other water current converters.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this publication and its amendment will
remain unchanged until the stability date indicated on the IEC web site 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 publication using a colour printer.

© IEC 2019
INTRODUCTION
This Technical Specification has been developed as a tool for the international marine energy
community, to assist in creating clarity and understanding. The wave, tidal and water current
energy industry has recently experienced a period of rapid growth and sector development.
With this expansion, it became apparent that a glossary of terms for the sector was required.
The aim of this Technical Specification is to present clear and consistent language that will
aid the development of programs, projects, and future standards.
This Technical Specification lists the terms that the marine energy industry commonly uses. It
is an evolving document that will change as new terms and symbols are added. The
terminologies herein have been harmonized with IEC 60050 and other IEC documents as far
as possible.
– 6 – IEC TS 62600-1:2011+AMD1:2019 CSV
© IEC 2019
MARINE ENERGY –
WAVE, TIDAL AND OTHER WATER CURRENT CONVERTERS –

Part 1: Terminology
1 Scope
This part of IEC 62600 defines the terms relevant to ocean and marine renewable energy. For
the purposes of this Technical Specification, sources of ocean and marine renewable energy
are taken to include wave, tidal current, and other water current energy converters.
Terms relating to conventional dam and tidal barrage, offshore wind, marine biomass, ocean
thermal and salinity gradient energy conversion are not included in the scope of this Technical
Specification.
This Technical Specification is intended to provide uniform terminology to facilitate
communication between organizations and individuals in the marine renewable energy
industry and those who interact with them.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1
added mass
extra mass associated with the additional force necessary to accelerate a body through a fluid
compared to the same acceleration in a vacuum
NOTE 1 In general, added mass is a variable that depends on the state of the unsteady motion and is not a
constant.
NOTE 2 In a viscous (real) fluid, the added mass would include kinetic energy of a fluid layer entrained by the
accelerating body.
2.2
added mass at infinity
limit of the mass corresponding to the added mass as the frequency tends to infinity
NOTE The value of added mass at infinity is normally necessary for time domain modelling of wave-body
interaction.
2.3
added mass coefficient
ratio between added mass and the mass of the water displaced by the submerged body
2.4
amplitude control
method to obtain the optimum oscillatory motion amplitude to capture a maximum of wave
energy
NOTE For a simple oscillating system, the object of amplitude control is to obtain a given oscillatory velocity
amplitude that should be related with the wave excitation force.

© IEC 2019
2.5
annual energy production (marine energy converter)
estimate of total energy production of a marine energy converter system during a one-year
period obtained by applying its power performance assessment to a prospective marine
energy resource characterization and assuming 100 % availability
NOTE Actual annual energy production is unlikely to exceed this estimate.
[IEC 60050-415:1999, 415-05-09, modified]
2.6
array (marine energy)
farm of marine energy converters arranged specifically so as to enhance energy capture
NOTE Array spacing is dictated by hydrodynamic considerations and may be very closely packed so as to
constitute a single platform or an arrangement of identical devices.
2.7
attenuator device
energy converter which is aligned parallel to the predominant direction of wave incidence
2.8
availability (marine energy converter)
ability of a marine energy conversion system to be in a state to perform a necessary function
under given conditions at a given instant of time or over a given duration, assuming that the
necessary external resources are provided
NOTE 1 For continuously running equipment availability equates to: uptime/(uptime + downtime).
NOTE 2 Where reliability is specified in Mean Time Between Failures (MTBF) and maintainability in Mean Time
To Repair (MTTR), availability also equates to: MTBF/(MTBF + MTTR).
[IEC 60050-191:1990, 191-02-05, modified]
2.9
capture area (tidal)
...