Lessons from the Acceptance Tests on the CEC Photovoltaic Pilot Plants

Official acceptance tests, involving performance measurement, visual inspection and functioning checks, have been carried out on all fifteen of the photovoltaic pilot plants in the European Commission' second 4-year programme of solar energy R&D. Equipment and procedures developed for on-site performance measurement have been successfully applied throughout the year - even in an English November.

All installations were found to be aesthetically pleasing, in accordance with CEC guidelines, but there is scope for reducing the costs of site preparation, support structures and array installation.

Some of the modules were of high quality but others had low efficiency, poor process control and unsatisfactory arrangements for mounting and interconnection -faults which should be remedied in today's highly competitive market. Measurement discrepancies could be reduced if all manufacturers adhered strictly to the current European standard, CEC Specification 101, Issue 2. A single international standard for reference cell calibration should be an aim for the future.

Varistors used for lightning protection should be carefully chosen to withstand the highest operational voltages over many years without the type of progressive degradation, which, as has been seen, may lead to catastrophic failure.