Health, safety and environmental aspects of the use of cadmium compounds in thin film PV modules

Abstract

Abstract BP Solar's Apollo thin film photovoltaic module fabrication process is based on the thin film semiconductors cadmium sulphide (CdS) and cadmium telluride (CdTe). It is a leading technology with aperture area efficiencies of more than 10% reported for devices of area 706 cm 2 and 7.8% for modules with aperture areas up to 4,540 cm 2 [1]. Throughout the world cadmium and cadmium compounds are regulated in the workplace and in the market place. In this paper some of the important health, safety and environmental issues associated with the use of cadmium compounds during the manufacture, use and disposal of Apollo thin film CdTe solar modules will be discussed. Evidence will be reported which indicates that the module fabrication process will have little defect on the workforce and the environment. Also tests indicate that the environmental impact from product use or as a result of a storage fire will also be very low. We will also demonstrate the viability of disposing of waste product in municipal landfill sites. This is possible because of the very small amounts of CdS and CdTe in the modules and because the levels of Cd leached from modules, are well below allowable limits, when tested by prescribed methods which aim to simulate landfill conditions.