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Light management in thin-film solar cells. Albert Polman Center for Nanophotonics FOM-Institute AMOLF Amsterdam, The Netherlands. Vanguard satellite 1958. The first practical solar panel (1954). Bell Laboratories (1954). 2010. Price per solar Watt vs. installed power. P. Maycock.
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Light management in thin-filmsolar cells Albert Polman Center for Nanophotonics FOM-Institute AMOLF Amsterdam, The Netherlands
The first practical solar panel (1954) Bell Laboratories (1954)
Price per solar Watt vs. installed power P. Maycock
Solar irradiance on earth Black dots: area of solar panels neededto generate allof the worlds primary energy (all energy consumed:electricity, heat, fossil fuels) assuming 8% efficient photovoltaics
Effects of Rshunt and Rseries on I-V curve Ideal IV curve Low Rsh Rsh = ∞ Rse = 0 High Rse
Light is poorly absorbed in a thin-film solar cell Solar spectrum absorbed in 2 m thick Si film
“Quantum defect” limits efficiency Photons are quantized energy packets: A 2 eV photon will give create max. 1 Volt over the p-n junction A 0.5 eV photon is not absorbed Eg(Si)=1.1 eV
Triple-junction tandem solar cell 1.5 V 1.0 V 0.5 V
Triple-junction tandem solar cell layer geometry From: Richard King (Spectrolab)
Efficiency limits of different solar cell types (2010) 3-junction tandem crystal Si wafer thin film: CdTe poly-Si amorphous Si organic/polymer dye-sensitized other Too expensive Too low efficiency 2009: CdTe thin film cells costs: < 1 $/W
Materials resources are limited Relative abundance of elements vs. atomic nr. • Requirements to construct 1 TW of PV with optically thick cells at 15% efficiency • Solutions: • 1) Earth Abundant Semiconductors (Si,Cu2O, Zn3P2, FeS2) • 2) Enhance Light Absorption/reduce semiconductor volume from P.H. Stauffer et al, Rare Earth Elements - Critical Resources for High Technology, USGS (2002)
… © Ron Tandberg