Equipment has been developed and installed for recording of :
- Meteorological data (global and diffuse horizontal irradiance, ambient temperature, wind speed and wind direction, the plane of array irradiance on the fixed racks and on the tracker) and module temperatures from the fixed racks and from the tracker;
- Module parameters (Isc, Voc, Vmp, Pmp) derived from the measured IV curves;
- Sets of full IV-curve data from the test modules.
CIS modules with output power at STC of up to 79W and CdTe modules with up to 50 W have been tested in the second field test phase.
Sixteen modules of each technology are installed on fixed racks at solar energy test sites in Helsinki, Widderstall and Tenerife; the tilt angle is adapted to the latitude of the site; continuous field tests are performed since autumn 2001.
Coefficients for parameter correction with respect to temperature and irradiance have been determined for open circuit voltage, short circuit current, fill factor and power. An empirical model has been developed to describe the outdoor module performance.
For both technologies no degradation has been observed for the second-generation modules since the installation in spring/summer 2003. Accelerated ageing experiments have been performed and delivered no indications for stability problems of both CIS as well as CdTe.
A successful market implementation is supported by outdoor performance data establishing a high level of confidence to the end user with respect to the quality and reliability of the product.