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Chapter 22 • Life Cycle Analysis of Photovoltaics: Strategic Technology Assessment 433

domestically; and for those used in European PV manufacturing, 89% is produced lo-
cally and 11% in China. Regarding CdTe PV panels, the two production countries, as of
2016, are malaysia and the uSA. The main production countries for CIGS PV are Japan
and China. All further upstream steps in the Si supply chain are analyzed considering
their actual geographical location—for instance, the production of metallurgical grade
Si (mG-Si) is divided among the main global producers, i.e., China, Russia, norway, and
the united States.
The individual local updated electricity mixes, used for all PV module manufacturing
and for the Si supplying countries, are also considered since they influence the amount of
PE ultimately required for each production process, as well as the associated environmen-
tal impacts.

22.4 Current Photovoltaic Life Cycle Analysis Results

22.4.1 Fixed-Tilt Ground-Mounted Photovoltaic Systems

Leccisi, Raugei, and Fthenakis have recently published a most of up-to-date LCA of the
major PV modules installed in fixed-tilt ground mounting utility-scale systems [7]. This
section summarizes the finding of their study. Fig. 22.3 shows the CEd of the analyzed PV
systems and Fig. 22.4 shows the GWP, both expressed per kW p —the stacked bars show the
individual contributions of the main life cycle stages. The average efficiency for each tech-
nology is assumed in accordance with the 2016 status report published by the Fraunhofer
Institute for Solar Energy Systems [8]—specifically: 17% for sc-Si PV, 16% for mc-Si, 15.6%
for CdTe PV, and 14% for CIGS PV. The reader should be aware that these efficiencies con-
tinue to improve and, correspondingly, the environmental indicators will continue to
improve as well.
The results clearly show that the most impacting step for c-Si technologies is the energy
intensive production of SoG Si and cell manufacturing.
Fig. 22.3 highlights that, per kilowatt (kW p ), c-Si PV systems are about twice as energy-
demanding to produce as CdTe PV systems.
Fig. 22.4 illustrates the resulting GWP indicator per kilowatt (kW p ): c-Si PV technologies
generally have higher values in comparison with thin film PV panels, and in particular, the
lowest GWP values are for CdTe PV.
As shown in Fig. 22.5, the EPBTs of the analyzed PV technologies were found to range
from 6 months (for CdTe PV installed in the uS South-West) to approximately 2–3 yr (for
c-Si PV installed in Central-northern Europe). here yr refers to year.

22.5 Technology Roadmaping

As shown in the previous section, among the currently commercial technologies c-Si tech-
nologies have the highest environmental impact, and the most impacting steps are silicon
feedstock and ingot growth, wafering, and cell processing. Thus to provide a paradigm of