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Updated: Jul 6, 2026
09:19
In Situ Monitoring of the Accelerated Performance Degradation of Solar Cells and Modules: A Case Study for Cu(In,Ga)Se2 Solar Cells
Published on: October 3, 2018
Emissions from photovoltaic life cycles.
Vasilis M Fthenakis1, Hyung Chul Kim, Erik Alsema
1PV Environmental Research Center, Brookhaven National Laboratory, Upton, New York, USA. vmf@bnl.gov
Environmental Science & Technology
|April 16, 2008
Summary
Photovoltaic (PV) technologies offer significant environmental benefits, emitting substantially less greenhouse gases and pollutants than conventional energy sources. Replacing grid electricity with PV power can prevent at least 89% of associated air emissions.
Area of Science:
- Environmental Science
- Materials Science
- Energy Policy
Background:
- Recent advancements in photovoltaic (PV) technologies necessitate updated environmental impact assessments.
- Annual production capacity and life cycle environmental performance of PV systems are rapidly evolving.
Purpose of the Study:
- To quantify and compare life-cycle emissions (greenhouse gases, criteria pollutants, heavy metals) for major commercial PV systems.
- To assess the environmental benefits of PV technologies against conventional energy sources.
Main Methods:
- Analysis of PV production data from 2004-2006 for four PV types: multicrystalline silicon, monocrystalline silicon, ribbon silicon, and thin-film cadmium telluride (CdTe).
- Life-cycle emission calculations using average European and US electricity mixes for materials and module production.
- Prospective analysis including the effect of PV breeders.
Main Results:
- Thin-film CdTe PV systems exhibit the lowest air emissions due to lower energy requirements in module production.
- Emissions differences among current PV technologies are minimal compared to the emissions from conventional energy.
- All PV technologies generate significantly lower life-cycle air emissions per GWh than fossil-fuel-based electricity.
Conclusions:
- Photovoltaic technologies provide substantial life-cycle environmental advantages over conventional energy sources.
- Displacing grid electricity with PV power can lead to a reduction of at least 89% in associated air emissions.
- Continued research and development in PV technologies are crucial for further environmental performance improvements.
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