Two international standards for photovoltaic glass led by CTC (China Building Materials Test and Certification Group Co., Ltd.)—IEC 62805-1:2017 "Photovoltaic (PV) glass — Part 1: Measurement of total haze and spectral distribution of haze" and IEC 62805-2:2017 "Photovoltaic (PV) glass — Part 2: Measurement of transmittance and reflectance"—were officially released and implemented on August 17, 2017. These are the first international standards for photovoltaic glass led and published by China, and also the first two IEC international standards successfully completed by CTC following its successful publication of six ISO international standards.

These two standards were approved and developed under IEC/TC 82, the technical committee for solar photovoltaic energy systems, which specializes in the development and revision of international standards in the solar photovoltaic field worldwide. During the entire development process, they went through multiple stages including NP, CD, CDV, and FDIS. Through multiple international meeting discussions, solicitation of comments, experimental verification, and voting, they ultimately obtained recognition from experts in most countries. IEC 62805-1 and IEC 62805-2 are standards for testing methods of photovoltaic performance of photovoltaic glass. Among them, IEC 62805-2 mainly specifies methods for measuring the transmittance and reflectance of glass for photovoltaic modules, and proposes calculation methods for effective hemispherical transmittance and reflectance. It can be widely applied to various types of photovoltaic glass used in photovoltaic modules, including ultra-white patterned glass, anti-reflective coated glass, transparent conductive oxide (TCO) glass, etc. IEC 62805-1 specifies a method for measuring and calculating the total haze and spectral distribution of haze of glass for photovoltaic modules, mainly applicable to transparent conductive oxide (TCO) glass and other photovoltaic glass. These two standards for the first time adopt the latest photon irradiance spectral parameters suitable for photovoltaic applications and specific spectral response ranges. By standardizing technical details such as test instruments, test procedures, calculation methods, and data processing, they provide comprehensive and accurate testing methods for the optical performance of photovoltaic glass, achieving international unification in testing technology. As the world's largest manufacturer of photovoltaic modules and the largest producer of photovoltaic glass, China's first IEC international standards for photovoltaic glass led by China will not only help improve the technology of China's photovoltaic glass industry and promote the healthy development of China's photovoltaic industry, but also enhance discourse power and international influence in the fields of standards and technology, especially enhancing the international competitiveness of China's photovoltaic testing.

The two international standards for photovoltaic glass released this time were led by the National PV Center of CTC. The CTC Glass and Photovoltaic Products Inspection and Certification Institute has two national-level quality inspection centers: the National Center for Quality Supervision and Inspection of Safety Glass and Quartz Glass and the National Center for Quality Inspection and Testing of Solar Photovoltaic (PV) Products. Among them, the National Safety Glass Center has nearly thirty years of certification, testing, and standards technology accumulation in architectural glass, automotive glass, aircraft glass, marine glass, etc., and since 1989 has carried out mutually trusted and mutually recognized testing and certification work with official institutions, certification bodies, and laboratories in the United States, Germany, the Netherlands, the United Kingdom, Brazil, and other countries. The National PV Center, after its official establishment in 2012, has developed rapidly and is now a CB laboratory recognized by the International Electrotechnical Commission IECEE. It has become the only comprehensive national-level third-party inspection and certification institution in China's photovoltaic field integrating inspection, certification, safety evaluation, instrument and equipment R&D, and standards research. The smooth approval, advancement, and completion of these two international standards for photovoltaic glass benefited from the long-term technical accumulation, continuous talent cultivation, and in-depth international exchanges of CTC's two national-level centers in the glass and photovoltaic fields, and especially from the long-term support of CTC leaders at all levels for international standards work and their forward-looking vision for CTC's future development. This not only lays a solid foundation for CTC's development in the photovoltaic testing and certification field and enhances the core competitiveness of CTC in the photovoltaic new energy field, but is also a successful practice of CTC in seizing opportunities to enter other fields on the basis of strengthening, expanding, and optimizing its existing businesses and building a comprehensive inspection and certification institution that is leading domestically, first-class internationally, and possesses sustained innovation capability and international competitive strength!