The breadth and coverage of analytical expertise in the IEA Technology Collaboration Programmes (TCPs) are unique assets that underpin IEA efforts to support innovation for energy security, economic growth and environmental protection. The 38 TCPs operating today involve about 6 000 experts from government, industry and research organisations in more than 50 countries1.

Energy Efficient End-Use Equipment (4E TCP)


Testing lamps to support international standards

The 4E TCP supports sound policy development in the field of energy efficiency end-use equipment by providing a forum for governments and other stakeholders to understand effective approaches to policy making. A comparison of results from 110 LED testing laboratories around the world has helped to improve the reliability of data for lighting products. 

Compared to incandescent lamp testing, test results of the perceived power of LED lamps vary significantly.*

Lighting constitutes approximately 15% of electricity consumption worldwide. It is estimated that wide scale deployment of energy efficient lighting products, in particular light emitting diodes (LED), could significantly reduce electricity consumption for lighting. Yet due to the wide variation in the quality and reliability of LED products available to consumers, ensuring consistent measurements among laboratories would increase market growth of LED products worldwide.

For these reasons, the 4E TCP set out to assist governments to monitor and verify the quality of LED products by conducting a comparison of LED testing laboratories. The project was carried out in compliance with the joint standard of the International Organization for Standards (ISO) and the International Electrotechnical Commission (IEC) (ISO/IEC 17043:2010, Conformity Assessment – General Requirements for Proficiency Testing), involving 110 laboratories located in 18 countries which contributed 123 data sets.

The products tested varied slightly taking into account popular models available in each of the three regional markets (Asia, North and South America and Europe). For each LED product tested, the laboratories measured the efficacy, brightness, light colour metrics and electrical properties.

While the results were relatively uniform across most of the participating laboratories, a few extreme measurements were observed which may have been caused by the participating laboratories’ inability to meet the requirements of the test method. After identifying the differences, the laboratories were able to refine their testing methods. In addition, the uncertainties reported by the laboratories were found to have a very large range: some significantly under estimated light colour metrics while others did not report uncertainties in the equipment used to measure the LEDs.

A key finding of the study is that accurately measuring LED qualities, in particular colour metrics, remains a challenge for the lighting industry. While data from these tests are now being used by participating laboratories to verify calibration of the equipment and to improve measurement practices, the wide variations demonstrate that the LED industry urgently needs practical methods and instruments as well as further education and training on evaluating uncertainty of the measuring equipment.

The results of the 4E TCP study contributed to the international test method for LED products published by the International Commission on Illumination, CIE International Standard S 025/E:2015. All of the results and conclusions of the 4E TCP project have been compiled in the final report, Solid State Lighting Annex: 2013 Inter Laboratory Comparison.

* Graph adapted from data provided by the 4E TCP


  • Electronic devices and networks
  • Engagement with international standardisation organisations
  • G20 energy efficiency action plan: networked devices
  • International mapping and benchmarking
  • Monitoring verification and enforcement
  • Motor systems
  • Policy-driven innovation
  • Smart metering infrastructure
  • Solid-state lighting
  • Technology forcing standards for energy efficiency


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Contracting Parties  12  1  -
Sponsors -  -

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