PV systems pose few environmental problems. The generating component produces electricity silently and does not emit any harmful gases during operation. The basic photovoltaic material for most common modules made out of silicon is entirely benign, and is available in abundance.

There are, nevertheless, some potential hazards allied to the production of some of the more exotic thin film technologies. The two most promising options, cadmium telluride and copper indium diselenide, both incorporate small quantities of cadmium sulphide, which poses potential cadmium risks module manufacture. Fortunately, there are well-established procedures governing the handling of such compounds, which are adhered to throughout the production process.

One criticism of early PV modules was that they consumed more energy during their production than they generated during their lifetime. With modern production methods and improved operational efficiencies this allegation is no longer true. The exact energy payback is obviously dependent on the available solar resource and on the degree to which the system is operational. High levels of solar irradiation and a high utilization factor will offer more rapid energy paybacks than if there is less sun and less usage, but typically energy payback will be realized within three to four years.

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