IEC TS 62862-2-1:2021

Solar thermal electric plants - Part 2-1: Thermal energy storage systems - Characterization of active, sensible systems for direct and indirect configurations

IEC TS 62862-2-1:2021 defines the requirements and the test methods for the characterization of thermal energy storage (TES) systems. This document contains the information necessary for determining the performance and functional characteristics of active direct and indirect thermal energy storage systems based on sensible heat in solar thermal power plants using parabolic-trough collector, Fresnel collector or tower central receiver technology with liquid storage media.
This document includes characterization procedures for testing energy storage system charge and discharge, as well as reporting the results. Test performance requirements are given and the instrumentation necessary for them, as well as data acquisition and processing methods and methods for calculating the results and their uncertainties.

General Information

• Status: Published
• Publication Date: 03-Feb-2021
• ICS: 27.160 - Solar energy engineering
• Technical Committee: TC 117 - Solar thermal electric plants
• Drafting Committee: PT 62862-2-1 - TC 117/PT 62862-2-1
• Current Stage: PPUB - Publication issued
• Start Date: 24-Feb-2021
• Completion Date: 04-Feb-2021

Standards Content (Sample)

IEC TS 62862-2-1 ®
Edition 1.0 2021-02
TECHNICAL
SPECIFICATION
colour
inside
Solar thermal electric plants –
Part 2-1: Thermal energy storage systems – Characterization of active, sensible
systems for direct and indirect configurations

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IEC TS 62862-2-1 ®
Edition 1.0 2021-02
TECHNICAL
SPECIFICATION
colour
inside
Solar thermal electric plants –

Part 2-1: Thermal energy storage systems – Characterization of active, sensible

systems for direct and indirect configurations

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.160 ISBN 978-2-8322-9320-1

– 2 – IEC TS 62862-2-1:2021 © IEC 2021
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 8
4 Symbols and abbreviated terms . 9
5 Thermal energy storage (TES) systems . 10
5.1 Classification of TES systems . 10
5.2 TES systems covered by this document . 10
5.3 TES system limits . 10
5.4 Key components . 10
6 Instrumentation and measurement methods. 11
6.1 General . 11
6.2 Flow rate measurements . 11
6.3 Temperature measurements . 11
6.3.1 Heat transfer fluid temperatures . 11
6.3.2 Wall temperatures . 12
6.4 Level measurements . 12
6.5 Meteorological signal measurements . 12
6.5.1 Wind speed and direction . 12
6.5.2 Ambient temperature . 12
6.6 Data acquisition . 13
7 General requirementson tests . 13
7.1 General . 13
7.2 Test procedure . 13
7.2.1 General . 13
7.2.2 Items to be included in the test procedure . 14
7.2.3 Items to be agreed between the parties . 14
7.3 Definition of the test included in this document . 15
7.3.1 General . 15
7.3.2 Test to determine the thermal efficiency of the storage system . 15
7.3.3 Test to determine the heat capacity of the storage system . 15
7.3.4 Test to determine the thermal losses of the storage system . 16
7.3.5 Test to determine the global losses of the storage system . 16
7.3.6 Test to determine the wall temperature . 16
7.4 Test boundaries . 17
8 Storage system characterization (storage thermal performance and capacity) . 18
8.1 Thermal efficiency and storage capacity (storage thermal performance and
capacity) . 18
8.1.1 Test methodology . 18
8.1.2 Calculation procedure . 19
8.2 Thermal losses of the storage system . 23
8.2.1 Test methodology . 23
8.2.2 Calculation procedure . 23
8.3 Global energy losses of the storage system . 24
8.3.1 General . 24

8.3.2 Test methodology . 24
8.3.3 Calculation procedure . 25
9 Verification procedure . 25
10 Test report (results) . 27
Annex A (informative) Thermal energy storage system types . 28
A.1 Thermal energy storage modes . 28
A.1.1 General . 28
A.1.2 Sensible heat storage . 28
A.1.3 Latent heat storage . 28
A.1.4 Thermochemical energy storage . 29
A.2 TES configuration . 29
A.3 Circulation of the storage medium . 29
Annex B (informative) Description of the main components of the active direct/indirect
TES using molten salts . 31
B.1 Storage media . 31
B.2 Tanks and foundation. 31
B.2.1 Tanks . 31
B.2.2 Foundations . 32
B.2.3 Insulation . 32
B.3 Materials . 32
B.4 Piping . 33
B.5 Pumps . 33
B.6 Heat exchanger . 33
B.7 Safety and control system . 34
B.7.1 General . 34
B.7.2 HTF and MSF leak detection system . 34
B.7.3 Instrumentation . 34
B.7.4 Freeze protection system . 34
B.7.5 Molten salt valves . 36
B.7.6 Blanketing system . 36
B.7.7 Welding control system . 36
B.8 Melting system . 36
Annex C (normative) Data adquisition and treatment . 38
C.1 Flow signal measurement . 38
C.2 Temperature signals measurement . 41
Annex D (informative) Documentation to be provided by the TES
manufacturer/supplier . 44
Annex E (normative) Test report . 46
Bibliography . 48

Figure 1 – Agreed duration between two charges . 16
Figure 2 – General typical diagram of the system and test boundaries for indirect TES
systems . 17
Figure 3 – General typical diagram of the system and test boundaries for direct TES
systems . 18
Figure 4 – Examples of criteria for comparison of the measurement (M) and the
reference value (RV) . 27

– 4 – IEC TS 62862-2-1:2021 © IEC 2021
Table 1 – List of symbols and units . 9
Table 2 – List of subscripts, superscripts and abbreviated terms . 9
Table 3 – Levels of confidence and associated coverage factors (Gaussian
distribution) . 26
Table C.1 – Cri
...