IEC TS 62257-4:2015

Recommendations for renewable energy and hybrid systems for rural electrification - Part 4: System selection and design

IEC TS 62257-4:2015(E) provides a method for describing the results to be achieved by the electrification system independently of the technical solutions that could be implemented. The purpose is to provide a method to assist project contractors and project developers to select and design the electrification system for isolated sites while matching the identified needs, such as those described in IEC TS 62257-2. The main technical changes with regard to the previous edition are as follows:
- redefine the maximum AC voltage from 500 V to 1 000 V, the maximum DC voltage from 750 V to 1 500 V;
- removal of the limitation of 100 kVA system size.
This publication is to be read in conjunction with IEC 62257 series.

General Information

• Status: Published
• Publication Date: 10-Dec-2015
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 27.160 - Solar energy engineering
• Technical Committee: TC 82 - Solar photovoltaic energy systems
• Drafting Committee: JWG 1 - TC 82/JWG 1
• Current Stage: PPUB - Publication issued
• Start Date: 15-Feb-2016
• Completion Date: 11-Dec-2015

Relations

• Revises: IEC TS 62257-4:2005 - Recommendations for small renewable energy and hybrid systems for rural electrification - Part 4: System selection and design
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC TS 62257-4 ®
Edition 2.0 2015-12
TECHNICAL
SPECIFICATION
Recommendations for renewable energy and hybrid systems for rural
electrification –
Part 4: System selection and design
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IEC TS 62257-4 ®
Edition 2.0 2015-12
TECHNICAL
SPECIFICATION
Recommendations for renewable energy and hybrid systems for rural

electrification –
Part 4: System selection and design

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.160 ISBN 978-2-8322-3071-8

– 2 – IEC TS 62257-4:2015  IEC 2015
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 9
4 Functional requirements of production and distribution subsystems . 10
4.1 General . 10
4.2 Overall needs to be satisfied . 11
4.2.1 Main factors to be considered . 11
4.2.2 Needs and characteristics to be considered . 11
4.3 Introduction to subsystems . 14
4.4 Functional description of a production subsystem . 15
4.4.1 General . 15
4.4.2 Detailed functions to be achieved by a production subsystem . 15
4.4.3 Detailed performances criteria to be achieved by a production
subsystem . 16
4.5 Functional description of a distribution subsystem . 16
4.5.1 Detailed functions to be achieved by a distribution subsystem (or rural

micro-grid) . 16
4.5.2 Detailed performances criteria to be achieved by a distribution
subsystem . 17
4.6 Functional description of a demand subsystem . 18
4.7 Constraints to be complied with by production distribution and demand
subsystems . 18
5 Energy management rules . 19
5.1 General . 19
5.2 Functional description for an energy management of an isolated system . 20
5.3 Demand side management . 21
6 Expected results from the sizing process . 21
6.1 Overview. 21
6.2 Participants in the sizing process . 21
6.3 Elements for comparing various design proposals . 21
6.4 Frameworks for proposal. 22
6.4.1 General . 22
6.4.2 General commitments to supply . 22
6.4.3 Assumptions and classification of input . 24
6.4.4 Technical characteristics for the main equipment proposed . 28
6.4.5 Characteristics for a photovoltaic array . 29
6.4.6 Characteristics for wind turbines . 30
6.4.7 Characteristics for the generator set . 31
6.4.8 Characteristics for micro hydro turbines . 32
6.4.9 Characteristics for biomass generators . 33
6.4.10 Characteristics for power converters . 33
6.4.11 Characteristics for the load manager/meter. 35
6.4.12 Characteristics for system controllers . 35
6.4.13 Characteristics for batteries . 36

6.4.14 Characteristics for links and wiring . 37
6.4.15 Energy outputs . 37
6.4.16 Presentation of the costs . 38
6.4.17 Design warranty . 38
6.4.18 Steps to reduce the impact of climatic hazards on system performance . 39
6.4.19 Presentation of the environmental and social impact. 39
6.4.20 Presentation of the socio- economic impact assessment. 39
6.5 Proposal for a sizing process . 39
6.6 Impact of design assumptions on system sizing and cost . 39
6.7 Guarantee of results . 41
7 Data acquisition rules for system management . 41
7.1 Overview. 41
7.2 General . 41
7.3 Levels of data acquisition and data necessity. 42
7.3.1 General . 42
7.3.2 Information to provide to the energy manager and relevant data to be
collected . 42
7.3.3 Information to provide to the operator and relevant data to be collected . 44
7.3.4 Information to provide to the user and relevant data to be collected . 45
7.3.5 Summary of the information required . 46
7.3.6 Scientific data collection . 46
7.4 Data to be collected . 46
7.5 Operating conditions, electrical and engineering requirements for data
acquisition . 48
Annex A (informative) Example for detailed performance criteria and levels for a
production subsystem . 49
Annex B (informative) Example for detailed performance criteria and levels for a
distribution subsystem . 50
Annex C (informative) Example framework for proposal specification . 51
C.1 Knowledge of site . 51
C.2 Knowledge of consumption data . 51
C.3 Knowledge of resources . 52
C.4 Technical characteristics for the main equipment proposed . 53
C.4.1 Photovoltaic modules . 53
C.4.2 Modules supporting structure . 53
C.5 Characteristics for wind turbines . 53
C.5.1 Wind turbine . 53
C.5.2 Structure support . 54
C.6 Characteristics for the generator set . 54
C.7 Characteristics for micro hydro turbine . 55
C.8 Characteristics for biomass generators . 55
C.9 Characteristics for power converters . 55
C.10 Characteristics for load manager/meter . 56
C.11 Characteristics for system controllers . 57
C.12 Characteristics for battery . 57
C.13 Energy outputs . 58
C.13.1 From renewable energies . 58
C.13.2 From fossil energies . 58
Annex D (informative) Formula for costs calculations . 59

– 4 – IEC TS 62257-4:2015  IEC 2015
D.1 Yearly cash flow. 59
D.2 Calculation of total life cycle cost . 59
D.3 Calculation of the levelized cost of energy . 60
D.4
...