The Energy and Environmental Performance of Ground-Mounted Photovoltaic Systems—A Timely Update

• Published in: Energies (Basel) Vol. 9; no. 8; p. 622
• Main Authors: Leccisi, Enrica, Raugei, Marco, Fthenakis, Vasilis
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.08.2016
• Subjects: Cadmium telluride; cadmium telluride (CdTe); Cadmium tellurides; Copper; copper indium gallium diselenide (CIGS); crystalline Si (c-Si); Electricity; Energy; Energy management; energy pay-back time (EPBT); ENERGY PLANNING, POLICY AND ECONOMY; energy return on investment (EROI); Environmental impact; environmental performance; Gallium; Global warming; Indium; Irradiation; life cycle assessment (LCA); net energy analysis (NEA); photovoltaic (PV); Photovoltaic cells; Silicon; Solar cells; SOLAR ENERGY; United States > US
• ISSN: 1996-1073; 1996-1073
• DOI: 10.3390/en9080622

Given photovoltaics' (PVs) constant improvements in terms of material usage and energy efficiency, this paper provides a timely update on their life-cycle energy and environmental performance. Single-crystalline Si (sc-Si), multi-crystalline Si (mc-Si), cadmium telluride (CdTe) and copper indium gallium diselenide (CIGS) systems are analysed, considering the actual country of production and adapting the input electricity mix accordingly. Energy pay-back time (EPBT) results for fixed-tilt ground mounted installations range from 0.5 years for CdTe PV at high-irradiation (2300 kWh/(m2 times yr)) to 2.8 years for sc-Si PV at low-irradiation (1000 kWh/(m2 times yr)), with corresponding quality-adjusted energy return on investment (EROIPE-eq) values ranging from over 60 to ~10. Global warming potential (GWP) per kWhel averages out at ~30 g(CO2-eq), with lower values (down to ~10 g) for CdTe PV at high irradiation, and up to ~80 g for Chinese sc-Si PV at low irradiation. In general, results point to CdTe PV as the best performing technology from an environmental life-cycle perspective, also showing a remarkable improvement for current production modules in comparison with previous generations. Finally, we determined that one-axis tracking installations can improve the environmental profile of PV systems by approximately 10% for most impact metrics.