IEC TS 62257-1:2015

IEC TS 62257-1 ®
Edition 3.0 2015-10
TECHNICAL
SPECIFICATION
colour
inside
Recommendations for renewable energy and hybrid systems for rural
electrification –
Part 1: General introduction to IEC 62257 series and rural electrification
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IEC TS 62257-1 ®
Edition 3.0 2015-10
TECHNICAL
SPECIFICATION
colour
inside
Recommendations for renewable energy and hybrid systems for rural

electrification –
Part 1: General introduction to IEC 62257 series and rural electrification

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.160 ISBN 978-2-8322-2914-9

– 2 – IEC TS 62257-1:2015  IEC 2015
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviations . 7
4 Methodology for rural electrification using hybrid renewable energy systems . 8
4.1 Rural electrification: which solution to choose? . 8
4.2 Decentralized electrification requiring a range of systems . 10
5 How to use the IEC 62257 series for a rural electrification project . 12
5.1 Overview. 12
5.2 Review of the IEC 62257 series: links with the phases of a rural
electrification project (see Table 3) . 15
5.2.1 Opportunity study . 15
5.2.2 Specification of a project . 15
5.2.3 Feasibility study of a project . 17
5.2.4 Detailed technical studies . 18
5.2.5 Implementation of a project. 19
5.2.6 Validation of a project . 20
5.2.7 On field operation . 21
Annex A (normative) Terms, definitions and abbreviations in use in the IEC 62257
series. 23

Figure 1 – Example of electrification progress following a master plan methodology . 9
Figure 2 – Example of electrification of a village using both CESs and IESs . 10
Figure 3 – Contractual relationship between project participants – (IEC TS 62257-
3:2015, Figure 1) . 16
Figure 4 – Example of the content of a non-technical preliminary study – (IEC TS
62257-2:2015, Figure 1) . 18
Figure 5 – TN-C-S system – (IEC TS 62257-5:2015, Figure B.2) . 19
Figure 6 – Phase A battery endurance test – (IEC TS 62257-8-1:2007, Figure 2) . 20
Figure 7 – Test 3, operating cycles – (IEC TS 62257-9-6:2008, Figure 3) . 21

Table 1 – Some advantages and disadvantages of the proposed single and multiple
user systems . 11
Table 2 – Contents of the 62257 series . 13
Table 3 – Utilization of the different parts of the IEC 62257 series according to the
main project phases . 14
Table 4 – Combined categorization – (IEC TS 62257-2:2015, Table C.1) . 17
Table 5 – Service specification (example) – (IEC TS 62257-2:2015, Table C.2) . 17
Table 6 – Verification of the adherence to commitments – (IEC TS 62257-6:2015,

Table 8) . 21
Table 7 – AOMR participant involvement – (IEC TS 62257-6:2015, Table 3) . 22

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RECOMMENDATIONS FOR RENEWABLE ENERGY
AND HYBRID SYSTEMS FOR RURAL ELECTRIFICATION –

Part 1: General introduction to IEC 62257 series and rural electrification

FOREWORD
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
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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 62257-1, which is a technical specification, has been prepared by IEC technical
committee 82: Solar photovoltaic energy systems. It was developed in cooperation with other
IEC technical committees and subcommittees dealing with renewable energies and related
matters, namely IEC technical committee 21 (Secondary cells and batteries), subcommittee

– 4 – IEC TS 62257-1:2015  IEC 2015
21A (Secondary cells and batteries containing alkaline or other non-acid electrolytes), IEC
technical committee 64 (Electrical installations and protection against electric shock), IEC
technical committee 88 (Wind turbines).
This third edition cancels and replaces the second edition issued in 2013. It constitutes a
technical revision.
The main technical changes with regard to the previous edition are as follows:
– Redefine the maximum AC voltage from 500 Va.c. to 1 000 Va.c., the maximum DC
voltage from 750 Vd.c. to 1 500 Vd.c. and removal of the limitation of 100 kVA system
size. Hence the removal of the word “small” in the title and related references in this
technical specification.
This technical specification shall be used in conjunction with the other documents of the
IEC 62257 series.
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
82/942/DTS 82/979/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.
A list of all parts in the IEC 62257 series, published under the general title Recommendations
for renewable energy and hybrid systems for rural electrification, can be found on the IEC
website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website 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 publicatio
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