IEC TS 62257-2:2015

Recommendations for renewable energy and hybrid systems for rural electrification - Part 2: From requirements to a range of electrification systems

IEC TS 62257-2:2015(E) proposes a methodological approach for the setting up and carrying out of socio-economic studies as part of the framework of decentralized rural electrification projects. It is addressed to project teams and in particular to experts in charge of socio-economic studies in international projects. This technical specification also provides some structures as technical solutions that could be recommended, depending on the qualitative and quantitative energy demands, consistent with the needs and financial situation of the customers. 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 62257-2:2004 - Recommendations for small renewable energy and hybrid systems for rural electrification - Part 2: From requirements to a range of electrification systems
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC TS 62257-2 ®
Edition 2.0 2015-12
TECHNICAL
SPECIFICATION
Recommendations for renewable energy and hybrid systems for rural
electrification –
Part 2: From requirements to a range of electrification systems
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IEC TS 62257-2 ®
Edition 2.0 2015-12
TECHNICAL
SPECIFICATION
Recommendations for renewable energy and hybrid systems for rural

electrification –
Part 2: From requirements to a range of electrification systems

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.160 ISBN 978-2-8322-3064-0

– 2 – IEC TS 62257-2:2015 © IEC 2015
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 8
4 Methodology for non-technical preliminary studies . 10
4.1 Place and role of preliminary studies in a decentralized rural electrification
project . 10
4.2 Specifications of the preliminary study . 10
4.2.1 General . 10
4.2.2 Data for a better understanding of the project environment . 11
4.2.3 Necessary data for the techno-economic study . 12
4.2.4 Necessary data for the financial analysis . 14
4.2.5 Necessary data for the organizational study . 15
4.3 The stages of a socio-economic study . 16
5 Classification of electrification systems . 16
5.1 Introduction to a range of systems . 16
5.2 Users requirements . 16
5.3 Typology of qualitative requirements . 16
5.3.1 Type of desired use . 16
5.3.2 Availability . 16
5.3.3 Quality of the supply . 17
5.4 Typology of quantitative requirements . 17
5.5 Classification for electricity services provided . 18
5.6 Assisted selection of production subsystem . 18
5.7 Typology of decentralized electrification systems . 19
5.7.1 General . 19
5.7.2 Selection process . 19
5.7.3 From user needs to electrification system – Summary for a range of
electrification systems . 20
6 Electrification systems architecture . 21
6.1 General . 21
6.2 General presentation of isolated electrification systems . 22
6.2.1 General . 22
6.2.2 Production subsystem. 22
6.2.3 Distribution subsystem . 22
6.2.4 User or application subsystem or demand subsystem . 22
6.3 Combining subsystems . 23
6.4 Functional diagrams . 25
6.5 Related references. 25
6.6 Limits between production, distribution and demand/application subsystems . 26
6.7 Summary of the different electrification system types . 26
Annex A (informative) Stages of a socio-economic study . 27
A.1 General . 27
A.2 Preparation phase. 27

A.3 Drawing up of the questionnaires – choice of surveyors and choice of
sample . 28
A.4 Conducting the survey – Analysis of the results . 28
A.5 Extrapolation of the results . 28
Annex B (informative) Analysis of the type of receivers installed versus types of use
and demonstrating seasonable variability (where applicable) . 29
B.1 Domestic use . 29
B.1.1 General . 29
B.1.2 Utilisation – Example 1 . 30
B.1.3 Utilisation – Example 2 . 31
B.2 Analysis of the type of receivers versus usage types . 32
B.2.1 General . 32
B.2.2 Health and care centre . 32
B.2.3 Worship places . 32
B.2.4 Community centre . 32
B.2.5 School . 33
B.2.6 Administrative premises . 33
B.2.7 Communication system . 33
B.2.8 Public lighting . 33
B.2.9 Pumping . 33
B.2.10 Battery charging station . 34
Annex C (informative) Supply quality indicators for isolated electrification systems . 35
Annex D (informative) Assisted selection of production subsystem . 36
D.1 Characteristics of possible production subsystems . 36
D.2 Assisted selection of a decentralized production system suited to the
requirement . 36
Annex E (informative) Functional diagrams . 38
E.1 Glossary of symbols . 38
E.2 Architectures of systems . 39
E.2.1 Type T I: REN Systems operating with no storage (in sync with solar,
wind or water energy sources) – REN production . 39
E.2.2 Type T I: Individual electrification systems – REN production with
energy storage . 43
E.2.3 Type T I: Individual electrification systems: (REN + diesel) production
without energy storage . 46
E.2.4 Type T I: Individual electrification systems: (RE + diesel) production
with energy storage . 49
E.2.5 Type T I: Individual electrification systems: genset only without storage . 51
E.2.6 Type T I: Individual electrification systems: genset only with storage . 52
E.2.7 Type T C: Collective electrification systems: REN only without storage . 53
E.2.8 Type T C: Collective electrification systems: REN Micropower plant
supplying a microgrid . 53
E.2.9 Type T C: Collective electrification systems: Multi sources micropower
plant (RE + diesel) without energy storage, supplying a microgrid . 56
E.2.10 Type T C: Collective electrification systems: Multi sources micropower
plant (RE + diesel) with energy storage supplying a microgrid . 59
E.2.11 Type T C: Collective electrification systems: Diesel micropower plant
supplying a microgrid . 62
E.2.12 Type T C: Collective electrification systems: Diesel micropower plant
with energy storage supplying a microgrid . 64

– 4 – IEC TS 62257-2:2015 © IEC 2015
Figure 1 – Example of the content of a non-technical preliminary study . 11
Figure 2 – Systems architecture and dispatchable energy . 20
Figure 3 – General configuration of an electrification system . 24
Figure A.1 – Flowchart of the stages of a socio economic study . 27
Figure D.1 – Better adequacy of production subsystems solutions with supply
availability and daily
...