What is ISO 9901 about?
ISO 9901 is an international document that gives recommended practice for the use of pyranometers in solar energy applications (e.g., testing of solar photovoltaic panels, solar thermal collectors or other devices, and performance monitoring of solar energy systems).
ISO 9901 is applicable for both outdoor and indoor use of pyranometers, when measuring plane of array, global horizontal and reflected irradiance, or radiation from a solar simulator.
Who is ISO 9901 for?
ISO 9901 on pyranometers of solar energy is applicable to:
- Manufacturing for electricity generating
- Companies dealing with natural gas, petroleum, coal, fossil fuel
- Pyranometers manufacturing
Why should you use ISO 9901?
Solar energy is a radiation which is produced from the Sun capable of producing heat, causing a chemical reaction, or generating electricity.
Pyranometer is a radiometer device designed for measuring the irradiance on a plane receiver surface which results from the radiant fluxes incident from the hemisphere above within the wavelength range from approximately 0,3 μm to about 3 μm to 4 μm.
ISO 9901 gives you the main application of pyranometer to assess the performance of photovoltaic solar power plants, that is power plants employing photovoltaic solar modules. The reflected irradiance measurement also has become more relevant with the increasing application of bifacial modules.
ISO 9901 provides you the benefits of pyranometers such as designing commercial solar power system, giving insulation requirements for building structures, etc, which helps in manufacturing the pyranometers for solar energy.
What’s changed since the last update?
PD ISO/TR 9901:2021 supersedes ISO/TR 9901:1990, which is withdrawn.
PD ISO/TR 9901:2021 includes some technical changes with respect to ISO/TR 9901:1990. These are:
- Adaptation of the terminology to the revised ISO 9060:2018 including reference to new “non-spectrally flat” and “fast response” instruments
- Added recommended practices for use of modern pyranometers with a digital output, including internal diagnostics
- Added recommended practices for use of pyranometers to measure “plane of array” and reflected radiation
- Added references to the main standards used in solar energy application of pyranometers: IEC 61724‑1:2017, ASTM G213‑17 and ASTM G183‑15
