IEC 61724-1-2021 PDF

Full title and description

St IEC 61724-1-2021 — Photovoltaic system performance — Part 1: Monitoring. This international standard defines terminology, equipment, data acquisition and methods for monitoring and analysing the performance of photovoltaic (PV) systems; it provides guidance for selecting monitoring system classes and establishes requirements used as a basis for other PV performance documents.

Abstract

IEC 61724-1:2021 sets out measurement, sensor and data-handling requirements for PV performance monitoring, including updated requirements for irradiance sensors, soiling measurement, and support for bifacial PV systems. The edition cancels and replaces the 2017 edition and refines monitoring system classes and recommendations.

General information

• Status: Current international standard (IEC publication).
• Publication date: 2021 (published July 2021; stability/review date noted as 2026).
• Publisher: International Electrotechnical Commission (IEC).
• ICS / categories: 27.160 (Solar energy engineering) — PV monitoring and related energy codes.
• Edition / version: Edition 2.0 (second edition, replaces 2017 edition).
• Number of pages: 136 pages (official published page count).

Scope

Defines terminology, measurement equipment, sensor installation and performance requirements, data acquisition, time-stamping and storage, quality checks and basic analysis methods for PV system performance monitoring. The standard supports selection and classification of monitoring systems for utility, commercial and smaller installations and provides the data framework used by other parts of the IEC 61724 series.

Key topics and requirements

• Terminology and definitions for PV monitoring and performance metrics (e.g., performance ratio, availability).
• Classification of monitoring system classes and guidance for choosing an appropriate class for a given installation.
• Sensor specifications and installation requirements, including updated irradiance sensor guidance and mounting practices.
• Measurement and monitoring provisions for bifacial PV systems and considerations for albedo and rear-side irradiance.
• Soiling measurement and recommended approaches reflecting recent measurement technologies.
• Data acquisition system requirements: sampling rates, time synchronization, data quality checks, storage and secure transfer.
• Calibration, uncertainty considerations and periodic verification of sensors and metering equipment.
• Reporting and minimum data sets to support performance analysis and to serve as a basis for other performance evaluation parts of IEC 61724.

Typical use and users

Used by PV system designers, asset owners, O&M teams, performance engineers, certifiers and researchers to specify and implement monitoring systems, verify system behaviour, diagnose underperformance, perform due diligence and support contractual performance guarantees. The standard is referenced when procuring monitoring equipment or framing test/reporting procedures.

Related standards

IEC 61724-1 is the foundation of the IEC 61724 series. Closely related documents include IEC TS 61724-2 (power performance index / capacity evaluation methods — latest revision published 2025) and IEC TS 61724-3 (energy performance evaluation methods, originally published as a technical specification). These parts define short-term power tests and extended-period energy evaluation methods that use data structured by Part 1.

Keywords

PV monitoring, photovoltaic performance, irradiance sensors, soiling measurement, bifacial PV, data acquisition, performance ratio, monitoring system classes, IEC 61724.

FAQ

Q: What is this standard?

A: IEC 61724-1:2021 is an international standard that specifies requirements and guidance for monitoring and acquiring data to evaluate the performance of photovoltaic systems.

Q: What does it cover?

A: It covers terminology, sensor and installation requirements (including irradiance and soiling), data acquisition and storage, time-synchronization, data quality checks, monitoring system classification, and baseline analysis methods used to interpret PV system performance.

Q: Who typically uses it?

A: PV system designers, asset owners, O&M and performance engineers, test laboratories, certifiers, consultants and researchers—anyone involved in deploying, operating or assessing PV-system performance.

Q: Is it current or superseded?

A: The 2021 edition (Edition 2.0) replaced the 2017 edition and is the current edition published by IEC; its stability/review date is noted in IEC records as 2026. Users should check for any amendments or newer editions if viewing this after the stability/review year.

Q: Is it part of a series?

A: Yes — IEC 61724 is a series addressing PV performance. Part 1 covers monitoring (this document), while related parts/technical specifications (such as IEC TS 61724-2 and IEC TS 61724-3) cover power performance tests and energy evaluation methods respectively.

Q: What are the key keywords?

A: Photovoltaic monitoring, performance ratio, irradiance, soiling, bifacial PV, data acquisition, sensor calibration, monitoring classes, IEC 61724.