January 2026: New Standards Advance Energy and Heat Transfer Engineering

Energy and heat transfer engineering is rapidly evolving, driven by the dual imperatives of sustainability and technological advancement. In January 2026, five new international standards were published, providing critical updates for professionals managing photovoltaic systems, refrigerant compressors, solid biofuels, fuel/air ratio controls, and hydrogen technologies. These standards define the benchmarks for safety, performance, and compliance, helping organizations maintain excellence amid regulatory shifts and innovation.

Overview / Introduction

As the globe transitions towards renewable energy and enhanced thermal processes, the field of energy and heat transfer engineering has never been more central—or more complex. Adhering to international standards is vital for delivering safe, efficient, and compliant systems. This article, the first part of a two-part series, examines the five latest standards published in January 2026, equipping industry leaders, engineers, quality specialists, and researchers with the knowledge to anticipate changes and streamline adoption.

Readers will gain insights into:

• The scope and key requirements of each standard
• Implications for various energy sectors and engineering applications
• The practical impact of new compliance regimes
• Technical guidance for implementation and testing

Detailed Standards Coverage

EN IEC 63409-3:2026 - Photovoltaic Power Generating Systems: Basic Operations

Photovoltaic power generating systems connection with the grid – Testing of power conversion equipment – Part 3: Basic operations

This European standard defines the essential test methods for confirming the basic operational characteristics of power conversion equipment (PCE) in photovoltaic (PV) power systems, with or without energy storage. Key focus areas include steady-state performance and transient-response evaluation, covering how PCE reacts to changes in grid voltage, frequency, and load within its continuous operable range.

Scope and Requirements:

• Specifies test conditions, sequences, equipment, and manufacturer tolerances
• Defines procedures for assessing operable ranges in power output (both active and reactive), voltage, frequency, and power factor
• Transient response tests analyze PCE performance during routine changes—excluding abnormal grid events (those are covered elsewhere)
• Provides normative annexes describing environment requirements, test result recording, and foundational concepts for operational limits

Who Should Comply:

• Manufacturers of PV inverters and power conversion hardware
• Installers and operators connecting PV systems to the power grid
• Grid integration and compliance engineers

Key highlights:

• Standardizes steady-state and transient response characterization for PV PCE
• Clarifies measurement procedures and interpretation of test data
• Supports harmonization across regions for grid-connected PV systems

Access the full standard:View EN IEC 63409-3:2026 on iTeh Standards

ISO 18976:2026 - Testing of Refrigerant Compressors

Testing of refrigerant compressors

ISO 18976:2026 establishes rigorous methodologies for testing refrigerant compressors, applicable to single-stage, two-stage, and economised designs. It details test procedures for evaluating refrigerating capacity, power input, isentropic efficiency, and volumetric efficiency. These accurate results ensure compressors are fit for their intended operational scenarios and application boundaries.

Scope and Specifications:

• Defines methods such as calorimetric and flow measurement techniques
• Addresses calculation methods for specific enthalpy, mass flow, and power input
• Describes uncertainty assessment, calibration protocols, and test condition selection
• Includes both steady state and transient operation periods
• Results can be leveraged for compressor suitability assessment, system design, and performance benchmarking

Who Should Comply:

• Compressor manufacturers
• Industrial refrigeration and HVAC system engineers
• Quality assurance and compliance assessors for refrigerant systems

Key highlights:

• Uniform test criteria for evaluating compressor performance
• Guidance on selection of most suitable test methods per application
• Incorporates updated calculation, measurement, and uncertainty protocols

Access the full standard:View ISO 18976:2026 on iTeh Standards

ISO 19743:2026 - Solid Biofuels: Heavy Extraneous Materials Determination

Solid biofuels — Determination of content of heavy extraneous materials larger than 3,15 mm

This new edition of ISO 19743 sets out a robust method for determining the content of heavy extraneous materials (HEM) greater than 3.15 mm in solid biofuels, especially woody biomass and hogfuel. Using sink-and-float separation and elutriation, it identifies high-density impurities—such as stones, glass, metals, and some plastics—that impact energy content and may damage fuel processing equipment.

Scope and Requirements:

• Applicable to solid biofuels, particularly in compliance with ISO 17225-1 and ISO 17225-9
• Details apparatus, sampling protocols, and separation procedures
• Emphasizes impurity impact on energy value, fuel usability, and maintenance
• Updated procedure for HEM calculation and improved sample processing clarity

Who Needs to Comply:

• Biomass fuel producers and suppliers
• Laboratories certifying biofuel quality
• Utilities and facilities procuring or processing solid biofuels

Key highlights:

• Enhanced sample preparation and impurity measurement accuracy
• Helps prevent equipment damage by detecting hazardous impurities
• Supports consistent biofuel sourcing and energy yield

Access the full standard:View ISO 19743:2026 on iTeh Standards

ISO 23552-1:2026 - Electronic Fuel/Air Ratio Control Systems

Control and protective devices for gaseous and liquid fuels — Particular requirements — Part 1: Electronic fuel/air ratio control systems, including associated sensors and mechanical actuators

ISO 23552-1:2026 specifies comprehensive safety, construction, performance, and testing requirements for electronic fuel/air ratio control (FARC) systems used with burners and appliances burning gaseous or liquid fuels. It covers closed-loop control, trim, and supervision systems, and is key to ensuring precise fuel-to-air mixing for safe, efficient combustion.

Scope and Specifications:

• Requirements for sensors, actuators, motors/blowers, and FARC system integration
• Rigorous functional safety (endurance, restart, accuracy, repeatability)
• EMC (electromagnetic compatibility) and protection against environmental stresses
• Comprehensive installation, marking, and operating instructions
• Test conditions, tolerances, construction standards, and manufacturer declarations

Who Needs to Comply:

• Burner and appliance manufacturers
• Fuel system integrators and process engineers
• Safety and regulatory compliance personnel in fuel and process sectors

Key highlights:

• Ensures inherent safety of fuel/air controls for burners and appliances
• Mandates thorough system testing beyond component-level assessment
• Facilitates global market access via harmonized fuel/air control criteria

Access the full standard:View ISO 23552-1:2026 on iTeh Standards

ISO/TS 15916:2026 - Hydrogen Technologies: Basic Safety Guidelines

Hydrogen technologies — Basic considerations for the safety of hydrogen systems

This technical specification from ISO outlines essential guidelines for safe handling, storage, and management of hydrogen in gaseous and liquid forms, as well as hydride-based storage. It introduces the physical and chemical hazards associated with hydrogen, elaborates on common risk mitigation strategies, and provides a basis for further safety requirements in specific applications.

Scope and Requirements:

• Identifies basic safety hazards, from combustion/explosion to embrittlement and health risks
• Addresses properties of hydrogen relevant to systems design and operational safety
• Covers infrastructure, system components, typical use cases, and facility considerations
• Provides general guidance on hazard mitigation and accident prevention, drawing on lessons from past incidents

Who Should Comply:

• Designers and operators of hydrogen systems (energy, mobility, industrial)
• Engineers responsible for integrating hydrogen technologies
• Occupational safety teams in hydrogen and energy sectors

Key highlights:

• Foundational safety principles for hydrogen across all storage and application forms
• Promotes risk reduction through design, technology selection, and operations
• Serves as a stepping stone for more detailed safety standards in hydrogen applications

Access the full standard:View ISO/TS 15916:2026 on iTeh Standards

Industry Impact & Compliance

The publication of these five standards marks a pivotal moment for the energy and heat engineering community. Compliance is more than a regulatory checkbox—adherence ensures systems are safe, resilient, and internationally interoperable. Key benefits include:

• Enhanced operational safety and reduced likelihood of catastrophic failures
• Consistent quality and performance across energy assets from PV arrays to hydrogen tanks
• Increased confidence among stakeholders, investors, and end users
• Harmonization, which supports cross-border trade and global supply chains

Compliance considerations:

• Review timelines for implementation—some standards may require immediate attention, others provide transition periods
• Update quality management systems, process control documents, and training curricula
• Engage with suppliers and integrators to certify compliance for new and retrofitted equipment
• Understand specific regional adaptations or superseded legacy standards

Risks of non-compliance can include equipment failure, legal penalties, reputational harm, and exclusion from key markets.

Technical Insights

While each standard addresses a unique area, several common themes emerge:

• Measurement accuracy: From power conversion and compressor testing to biofuel sampling, precise instrumentation and calibration are essential.
• Testing environments: Each standard sets out recommendations for stable, representative test conditions—essential for reproducibility and meaningful benchmarks.
• Systems integration: Whether designing inverter responses for grid events, or embedding fuel/air ratio controls, standards emphasize system-level safety and interoperability.
• Safety and resilience: Standards explicitly require strategies for coping with real-world anomalies—from voltage swings and frequency shifts, to impurity ingestion and explosive risk.
• Documentation and recordkeeping: Across the board, rigorous reporting of test procedures, data, and outcomes enables traceability and ongoing quality assurance.

Best practices for implementation:

1. Establish cross-functional teams (engineering, quality, operations) to interpret and apply test protocols.
2. Invest in modern test and measurement systems aligned to the latest standards.
3. Regularly calibrate equipment and validate methods against reference materials.
4. Maintain clear documentation linking standard clauses to internal procedures.
5. Engage with international peer networks to keep current with evolving requirements.

Testing and certification:

• Engage accredited laboratories for independent testing when required
• Leverage manufacturer declarations and conformity assessments as part of market access
• Participate in standardization committees to represent your organization's needs and stay ahead of future changes

Conclusion / Next Steps

These five standards, published in January 2026, collectively set a new bar for energy and heat transfer engineering excellence. Whether your organization designs, manufactures, procures, or operates energy systems, incorporating these guidelines will drive safety, quality, and competitiveness for years to come.

Recommendations:

• Review each relevant standard in full and update compliance checklists
• Integrate new protocols into product development and operations
• Train teams on updated requirements and safety practices
• Monitor iTeh Standards and industry bulletins for Part 2 of this update and further guidance

Ready to stay ahead? Browse all current and emerging energy and heat transfer engineering standards on iTeh Standards

By understanding and applying these international standards, energy professionals position themselves at the forefront of technical innovation, safety, and sustainability.