TC 117 - Solar thermal electric plants

IEC 628621-6:2024 specifies the technical requirements (safety and physical parameters), test methods, inspection rules and intervals, sampling, judgment, marking, labelling and accompanying documents, packaging, transportation and storage, recycling and disposal of silicone-based heat transfer fluids (SiHTF) for use in line-focusing solar thermal power plants.
The application of polydimethylsiloxane-based heat transfer fluids for this type of installation is covered in this document. Owing to their chemical nature and composition, the introduction of new test methods to determine the applicability and the thermal stability of SiHTF is included in this document.

IEC 62862-1-5:2024 provide procedures and guidelines to carry out acceptance tests for solar thermal power plants, of any concentration technology, with the uncertainty level given in ISO/IEC Guide 98-3.
This document establishes the measurements, instrumentation and techniques required for determining the following performance parameters for a given period:
- available solar radiation energy,
- plant electricity consumptions,
- net electricity generation,
- non-solar energy,
- net plant efficiency.
This document specifies the characteristics of a calculation tool that serves as a reference for expected electricity production during the test period and under real-time solar irradiance and other meteorological data.
This document is applicable to solar thermal power plants of any size using any concentration technology, where the sun is the main source of energy, and all elements and systems are operative. Such power plants can optionally have non-solar energy sources, such as natural gas or other renewable energies, and a thermal storage system.
This document is applicable to acceptance testing in such power plants, as well as in any other scenario in which their performance must be known.

IEC 62862-4-1:2022 specifies the general requirements for the design of solar power tower plants and covers the electric power system requirements, the solar resource assessment, the site selection, the overall planning, the layout of the heliostat field and the receiver tower, the layout of the power block, the collector system, the heat transfer, the thermal energy storage and steam generation system, the steam turbine system, the water treatment system, the information system, instrumentation and control, the electrical equipment and system, occupational safety and occupational health. This document is applicable to the design requirements of newly built, expanded or rebuilt solar power tower plants employing steam turbines with molten salt or water-steam as heat transfer fluid.

IEC 62862-5-2:2022 specifies the requirements and the test methods for the characterization of a large-size linear Fresnel collector.
This document covers the determination of optical and thermal performance of linear Fresnel collectors, and the tracking accuracy of the collector one-axis tracking system. This test method is for outdoor testing only.
This document applies to linear Fresnel collectors according to Annex A equipped with the manufacturer-supplied sun tracking mechanism.
This document applies to the whole collector field in-situ or as a minimum unit to be tested to an individual collector string (loop) connected to the main piping (flow, return flow) to and from a heat sink, covering the full temperature range of the field.

IEC 62862-3-1:2022 specifies the general requirements for the design of parabolic-trough solar thermal power plants. It includes requirements for the electric power system, solar resource assessment, site selection, overall planning, collector system, heat transfer system, thermal energy storage system, steam generation system, steam turbine system, layout of solar field, layout of power block, electrical equipment and system, water treatment system, instrumentation and control, auxiliary system and ancillary facilities, as well as considerations concerning health and safety.
This document is applicable to the design of new, expanded or rebuilt parabolic-trough solar thermal power plants using a steam turbine.

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.

IEC TS 62862-3-3:2020 specifies the technical requirements, tests, durability and technical performance parameters of solar thermal receivers for absorbing concentrated solar radiation and transferring the heat to a fluid used in concentrated solar thermal power plants with linear-focus solar collectors. The receivers addressed consist of an absorber tube and an insulating glass envelope tube.
This document includes the definitions of technical properties and characterization of geometry and performance parameters as well as the test methods for optical characterization, heat loss, and durability. For the sake of clarity, it is stated here that the thermal loss tests described in this document do not deliver the thermal loss of the receiver tubes when they are installed in commercial solar fields.

IEC 62862-3-2:2018 specifies the requirements and the test methods for the characterization of a large-size parabolic-trough collector. This document covers the determination of optical and thermal performance of parabolic-trough collectors, and the tracking accuracy of the collector one-axis tracking system. This test method is for outdoor testing only. This document applies to parabolic-trough collectors equipped with the manufacturer-supplied sun tracking mechanism.

IEC TS 62862-1-1:2018(E) 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.

IEC TS 62862-1-2:2017(E) defines the procedures for the creation of annual solar radiation data sets (ASR) for solar thermal electricity (STE) plant simulation. This document defines procedures needed for the ASR construction as well as its components and parameters. The scope of application of this document refers to the needs associated with solar thermal power plant projects and mainly related to the simulation of an annual period with a solar radiation sum close to a normal annual value (from among an estimation of all possible annual values).

IEC TS 62862-1-3:2017(E) defines a data format for meteorological data sets. The goal of this document is to reduce efforts for data exchange and to avoid errors caused by misunderstandings due to the application of various different and at times unclear formats.