IEC TS 62600-20:2019

IEC TS 62600-20 ®
Edition 1.0 2019-06
TECHNICAL
SPECIFICATION
colour
inside
Marine energy – Wave, tidal, and other water current converters –
Part 20: Design and analysis of an Ocean Thermal Energy Conversion (OTEC)
plant – General guidance
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IEC TS 62600-20 ®
Edition 1.0 2019-06
TECHNICAL
SPECIFICATION
colour
inside
Marine energy – Wave, tidal, and other water current converters –

Part 20: Design and analysis of an Ocean Thermal Energy Conversion (OTEC)

plant – General guidance
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.140 ISBN 978-2-8322-6915-2

– 2 – IEC TS 62600-20:2019 © IEC 2019
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 11
2 Normative references . 12
3 Terms and definitions . 13
4 Abbreviated terms and acronyms . 15
5 Site specific and metocean design parameters . 15
5.1 Environmental factors influencing design . 15
5.1.1 General . 15
5.1.2 Seawater temperature . 16
5.1.3 Wind . 16
5.1.4 Waves . 16
5.1.5 Water depth and sea level variations . 17
5.1.6 Currents . 17
5.1.7 Marine growth . 17
5.1.8 Other meteorological and oceanographic information . 17
5.1.9 Water chemistry . 17
5.1.10 Third party (collision, anchor impact, trawling, Unexploded Ordinance
(UXO) . 17
5.1.11 Soil/seabed conditions . 18
5.2 Biological impact . 18
6 Floating OTEC – General information and guidance (closed cycle, deep water) . 18
6.1 Seawater considerations . 18
6.2 Cold seawater system . 19
6.2.1 Systems engineering considerations . 19
6.2.2 Cold water pumping power considerations . 20
6.2.3 CWP dynamic response . 20
6.2.4 Static Loads and bending moments . 21
6.2.5 Suction collapse . 21
6.2.6 Deflection by current and platform motions . 21
6.2.7 Analysis of loads and displacements . 22
6.2.8 Recommendations for qualification of the Cold Water Pipe (CWP) . 22
6.2.9 Analysis approach . 22
6.3 Warm seawater system . 22
6.3.1 Warm water intake (screen) . 22
6.3.2 Warm water ducting and pumps . 23
6.3.3 Biofouling control . 23
6.4 Seawater discharge arrangement and plume analysis . 23
6.4.1 Seawater discharge ducts . 23
6.4.2 Seawater pumps . 23
7 Process system . 24
7.1 Working fluid selection . 24
7.2 Heat exchanger (HX) selection . 25
7.3 Materials compatibility . 25
7.4 Process system risks and hazards . 25
8 Platform type . 25

8.1 General . 25
8.2 Mooring/Station keeping . 26
8.2.1 Grazing OTEC plants (no power export cable required) . 26
8.2.2 Non-grazing OTEC plants . 26
9 Power export . 27
9.1 General . 27
9.2 Design considerations . 27
9.3 Platform based equipment . 27
9.4 Transmission cable . 27
9.5 Land based equipment . 28
10 Energy storage and transfer system . 28
10.1 General . 28
10.2 Hydrogen . 28
10.3 Ammonia . 28
10.4 Methanol . 28
10.5 Battery storage . 28
11 Land and shelf-based OTEC . 29
11.1 General information and guidance. 29
11.2 CWP design for land and shelf-based OTEC plants . 29
12 Risk based approach for the design and operations of OTEC plants . 30
12.1 Risk assessment . 30
12.2 Risk based design. 30
12.2.1 Risk assessment process . 30
12.2.2 Prototype testing . 31
12.3 Risk based operational guidelines . 31
12.3.1 Floating plant . 31
12.3.2 Operating plant . 31
12.3.3 Product export risks/hazards . 31
13 Transportation and installation (T&I) . 32
14 Commissioning and handover . 32
15 Operations, inspection and maintenance . 33
15.1 General . 33
15.2 Operations . 33
15.3 Inspection and maintenance . 34
15.4 Hazards and safety . 35
15.4.1 Hazards . 35
15.4.2 Safety . 35
16 Decommissioning . 36
Annex A (informative) OTEC potential and its history . 38
A.1 OTEC potential . 38
A.2 Installation sites . 39
A.3 Previous OTEC projects . 39
A.4 Open cycle OTEC . 40
Bibliography . 41

Figure 1 – Tropical ocean temperature-depth profile . 7
Figure 2 – Working principle of closed cycle ocean thermal energy conversion [2] . 8

– 4 – IEC TS 62600-20:2019 © IEC 2019
Figure 3 – Major power cycle components of a closed cycle OTEC plant . 9
Figure 4 – Open cycle OTEC system . 10
Figure 5 – Example of a typic
...