IEC TS 62862-1-1:2018

IEC TS 62862-1-1 ®
Edition 1.0 2018-02
TECHNICAL
SPECIFICATION
colour
inside
Solar thermal electric plants –
Part 1-1: Terminology
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IEC TS 62862-1-1 ®
Edition 1.0 2018-02
TECHNICAL
SPECIFICATION
colour
inside
Solar thermal electric plants –

Part 1-1: Terminology
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.160 ISBN 978-2-8322-5352-6

– 2 – IEC TS 62862-1-1:2018 © IEC 2018
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
3.1 SECTION 01: DESCRIPTION OF SYSTEMS, SUB-SYSTEMS AND
COMPONENTS . 5
3.2 SECTION 02: ANGLE DEFINITIONS . 9
3.3 SECTION 03: AREA DEFINITIONS . 16
3.4 SECTION 04: OPTICAL PROPERTIES . 18
3.5 SECTION 05: SOLAR IRRADIANCE . 24
3.6 SECTION 06: ENERGIES DEFINITION (SOLAR FIELD PART) . 25
3.7 SECTION 07: ENERGIES DEFINITION (POWER BLOCK PART) . 26
3.8 SECTION 08: EFFICIENCY NUMBERS . 28
3.9 SECTION 09: THERMAL STORAGE SYSTEM . 30
3.10 SECTION 10: FINANCIAL FIGURES . 32
3.11 SECTION 11: MISCELLANEOUS . 32

Figure 1 – Angle of acceptance of specular reflectance, ψ . 10
Figure 2 – Angles of incidence in linear Fresnel collectors . 11
Figure 3 – Collector axis azimuth angle and collector normal azimuth angle (example
for northern hemisphere) . 12
Figure 4 – Rim angle of a parabolic-trough collector . 14
Figure 5 – Illustration of solar azimuth angle definition in the northern hemisphere . 15
Figure 6 – Illustration of solar azimuth angle definition in the southern hemisphere . 15
Figure 7 – Typical interconnection of the power generation (G), the auxiliary power
transformer and the main power transformer in a solar thermal electricity plant . 27

Table 1 – Optical terms and symbols. . 18

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SOLAR THERMAL ELECTRIC PLANTS –

Part 1-1: Terminology
FOREWORD
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Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC TS 62862-1-1, which is a technical specification, has been prepared by IEC technical
committee 117: Solar thermal electric plants.

– 4 – IEC TS 62862-1-1:2018 © IEC 2018
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
117/75/DTS 117/85/RVDTS
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 document has been drafted in accordance with the ISO/IEC Directives, Part 2.
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SOLAR THERMAL ELECTRIC PLANTS –

Part 1-1: Terminology
1 Scope
This part of IEC 62862 contains the main terms and definitions used by the solar thermal
electric (STE) industry and intends to be a reference for users of industry documents.
Since the components and configurations of STE plants depend on the concentrating solar
thermal technology used (i.e., central receiver, parabolic-trough collector, parabolic-dish or
linear Fresnel concentrator), some terms are not applicable to all types of STE plants and
notes have been introduced in their definitions for clarification.
The reference STE plant configuration assumed is composed of three main subsystems: solar
field, power block and (eventually) thermal storage system.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
ISO 9488:1999, Solar energy – Vocabulary
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1 SECTION 01: DESCRIPTION OF SYSTEMS, SUB-SYSTEMS AND COMPONENTS
3.1.1
absorber
element of the receiver absorbing radiant solar energy and transferring it to a fluid in the form
of heat
3.1.2
absorber cover
transparent element that covers the absorber to reduce heat losses and provide weather
protection
Note 1 to entry: When this element is made of glass it is usually referred to as a "glass cover".
3.1.3
active length of a linear receiver
length of the absorber exposed to concentrated solar radiation, at a reference temperature

– 6 – IEC TS 62862-1-1:2018 © IEC 2018
Note 1 to entry: This temperature is 25 °C if not otherwise stated. The absorber length considered to be exposed
is that where the radiation impinging normal to the absorber's surface is not shadowed.
Note 2 to entry: Unit: the SI unit is m.
3.1.4
auxiliary heater
equipment in which thermal energy is transferred to the heat transfer fluid by means of
non-solar fuel consumption
3.1.5
collector aperture normal
vector perpendicular to the collector aperture plane
3.1.6
collector aperture plane
plane, perpendicular to the collector transversal plane, that contains the solar thermal
collector aperture area
3.1.7
collector axis
straight line resulting from the intersection of the
collector aperture plane and a plane containing the linear receiver and perpendicular to the
collector aperture plane
SE
...