By Kari Williamson

The project partners of the Network of Excellence Distributed Energy Resources Laboratory (DERlab) aim to internationally unify long-term measurements of solar modules under real conditions.

The solar PV module testing standard will be published at the beginning of October.

“The demand for measurements under real conditions is increasing. We have reacted to this by developing this new standard,” says Professor Nikos Hatziargyriou, Chairman of the DERlab workshop.

The standard will be for long-term measurement of the effective energy output, providing procedures for energy rating of solar PV modules outside laboratory conditions.

Under the testing standard, two solar PV modules will be tested for at least a year in parallel field tests, and a third solar PV module will be kept in a dark place and used as a comparison.

The current and voltage at the maximum power point of the solar PV module will be recorded every 15 seconds. In addition, it will measure the irradiation strength and the module temperature and capture the overall current/voltage characteristic.

“With this new standard, DERlab creates uniform measuring procedures with which one can directly compare the energy yield of solar modules site-specifically in different locations and under the most varying of climatic conditions”, says Roland Bründlinger, Board Chairman of DERlab.

“While the IEC standards consider specially the performance of partial aspects of the solar power plants, it is our objective to characterize the entire system in the future as a whole. Thus we shortly plan to incorporate inverters in the testing as well.”

The Network of E xcellence DERlab is being promoted by the European Commission, the Fraunhofer Institute for Wind Energy and Energy System Technology (IWES), and partners.

DERlab e.V. was founded in Kassel, Germany, in 2008.