Carbon Footprint of rooftop PV systems from different technologies in southern Europe (optimal inclination & irradiation of 1700 kWh/m2/yr).
Source: de Wild-Scholten (ECN), Sustainability: Keeping the Thin Film Industry green, 2nd EPIA International Thin Film Conference, Munich, 2009).

Carbon Footprint of different electricity sources.
Specification: PV (CdTe/1700 kWh/m2 & optimally inclination)
Source: de Wild-Scholten (ECN), Sustainability: Keeping the Thin Film Industry green, 2nd EPIA International Thin Film Conference, Munich, 2009).

Life-cycle emissions from silicon and CdTe PV modules. BOS is the Balance of System (i.e., module supports, cabling and power conditioning).
Specification: Ground-mounted systems, Southern European insolation, 1,700 kWh/m2/yr, performance ratio of 0.8, and lifetime of 30 years.  Case 1- current electricity mixture in Si production-CrystalClear project and Ecoinvent database. Case 2- UCTE grid mixture and Ecoinvent database. Case 3- US grid mixture and Franklin database
Source: Fthenakis, Kim and Alsema, Emissions from Photovoltaic Life Cycles, Environmental Science and Technology, 42(6):2168–2174).

Preliminary projections of Global Warming Potential (GWP) for selected PV technologies in the years 2025 and 2050. Assumed efficiency and lifetimes are: sc-Si today 14%/30 years; ribbon-Si 2025 20%/35years; CdTe 2025 13%/35years; ribbon-Si 2025 22%/40years; CdTe 2050 16%/40years and DCS 2050 17%/15years. Source: M. Raugei and P. Frankl, Life cycle impacts and costs of photovoltaic systems: current state of the art and future outlooks, Energy 34 (2009), 392-399.