The standard for PV system performance monitoring has been revised. The new version, released February , defines “accuracy classes”. Abstract — After a PV system is installed, periodic analysis is necessary to track how measured performance meets expectations. IEC outlines methods . The IEC standard for PV system performance monitoring has been revised. This is relevant for system owners, O&M managers.
|Published (Last):||7 July 2016|
|PDF File Size:||17.26 Mb|
|ePub File Size:||10.46 Mb|
|Price:||Free* [*Free Regsitration Required]|
The new scope not only defines the measuring system components and procedures as in the versionbut also aims to keep 617244 errors within specified limits.
The new version of the standard is fundamentally different from the version. There are two reasons for the extra steps prescribed by IEC to comply with an optimal Class A: Heating and ventilation of solar radiation sensors keeps the glass temperature above dewpoint and free from dew and frost deposition. It addresses sensors, installation, and accuracy for monitoring equipment in addition to measured parameter data acquisition and quality iev, calculated parameters, and performance metrics.
It is no use having only one or a few instruments Class A.
Quick facts on the IEC 61724-1 standard for PV stakeholders
Both standards define Class A, B and C but with a different meaning. Class B medium accuracy. The solution with true air ventilation, not air circulation.
The standard contains detailed specifications at monitoring system component level. It specifies for each class of monitoring system the pyranometer class that must be used, including required instrument ventilation and heating, azimuth and tilt angle accuracy. To achieve this, dew, frost, soiling and instrument deposition as such should be prevented, and customers have to do good product maintenance.
A survey showed that the main reason for most companies not to aim for a Class A status for IEC, is the cost-benefit analysis they made. You should at least do all of the below:. Introduction The first edition of IEC Class A high accuracy.
It shows requirements for solar radiation measurements and which pyranometers comply. The following tables offer an overview of the main elements of the IEC monitoring classification system, its requirements for solar radiation measurement and which pyranometers comply in which accuracy class.
It is too costly to obtain a Class A status:. Once every 2 years. It also defines cleaning and calibration intervals for pyranometers. It now has been updated. In conformity declarations, providers must state the accuracy class of the measurement. It does so by establishing accuracy classes for monitoring systems. The version of the standard recognises that the solar irradiance measurement is one of the weakest links in the measurement chain.
The classes A, B and C are site requirements; all individual onsite measurement instruments have to be Class A, in order to obtain a Class A status of the site.
For pyranometers, the following costs are associated with Class A: Figure 1 frost and dew deposition: It outlines equipment, methods, and terminology for performance isc and analysis of photovoltaic PV systems. Pyranometer domes are made of glass.
The IEC standard for PV monitoring systems. A quick explanation. | Hukseflux
This significantly increases the reliability of the measured data. Class A means great care for the maintenance of your pyranometers A survey showed that the main reason for most companies not to aim for a Class A status for IEC, is the cost-benefit analysis they made. Emerainville – France T: The class is not only determined by the hardware that is used, but ifc by quality checks and measurement procedures.
Why heating and ventilation?
This memo offers comments on consequences of the new standard concerning the selection of pyranometers.