EN IEC 61400-12-1:2022/prA1:2025

Overview

EN IEC 61400-12-1:2022/prA1:2025 is an amendment to the international standard addressing power performance measurements for electricity producing wind turbines. Issued by CLC, this standard is central to the wind energy industry, providing updated guidance for accurate and consistent measurement practices. The amendment clarifies and revises key procedures and definitions, especially relating to the correction of air pressure and temperature measurements to the turbine hub height, aligning practices with ISO 2533:1975.

This amendment is currently in the Committee Draft for Vote stage and is relevant for manufacturers, developers, operators, and certifying bodies within the wind energy sector.

Key Topics

• Revised Air Pressure Measurement:

  • The amendment updates the definition and approach to measuring and averaging air pressure, ensuring it is corrected to the wind turbine hub height.
  • Introduces and clarifies the use of additional measurement variables, such as pressure at sensor height and precise elevation differences.

• Hub Height Corrections:

  • Details the requirement to correct air pressure and temperature measurements to hub height, enhancing accuracy in performance evaluation.
  • Aligns correction methodology with ISO 2533:1975, using established equations and temperature gradients.

• Updated Symbols and Terms:

  • Adds new abbreviations and definitions for terms related to air pressure and sensor elevation.
  • Ensures standardized use of units and nomenclature for technical clarity.

• Procedural Consistency:

  • Provides clear instructions for correcting both air pressure and air temperature, reducing ambiguity in measurement and reporting practices.
  • Specifies that temperature adjustments follow a -0.0065 K/m gradient, as stipulated in ISO 2533:1975 Table 4.

Applications

The updates in EN IEC 61400-12-1:2022/prA1:2025 deliver practical benefits across the wind energy sector:

• Turbine Manufacturers:

  • Ensure devices meet international requirements for performance measurement.
  • Provide verifiable data to clients and stakeholders.

• Wind Farm Operators and Developers:

  • Achieve precise calculation of actual power performance under varied climatic and site-specific conditions.
  • Use accurate, standardized data for site assessment, energy yield predictions, and project financing.

• Testing Institutes and Certifying Bodies:

  • Enhance comparability of wind turbine performance data across projects and markets.
  • Facilitate compliance assessments and certifications backed by harmonized measurement procedures.

• Engineering Consultants:

  • Base feasibility studies and technical due diligence on internationally consistent data and reporting formats.
  • Reduce error margins in wind energy resource assessment.

Related Standards

Professionals working with EN IEC 61400-12-1:2022/prA1:2025 may also reference:

• ISO 2533:1975 - Standard atmosphere, as directly referenced for pressure and temperature corrections.
• EN IEC 61400-12-1:2022 - The main document governing power performance measurements for wind turbines.
• IEC 61400 Series - Broader suite of standards covering all facets of wind energy generation systems, including design, safety, and grid integration.

By staying current with EN IEC 61400-12-1:2022/prA1:2025, stakeholders in the wind energy market gain improved accuracy, transparency, and comparability in turbine power performance assessment, supporting more reliable project outcomes and streamlined certification processes.