Bay Area Photovoltaic Consortium Introduction and Opportunities John P. Benner BAPVC Executive Director 2 nd Annual c-si PVMC Workshop July 10, 2013 at Intersolar. This material is based upon work supported by the Department of Energy through the Bay Area Photovoltaic Consortium under Award Number DE-EE0004946. Bay Area Photovoltaic Consortium
Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency hereof. Bay Area Photovoltaic Consortium 2
Bay Area Photovoltaic Consortium Purpose Support university research nationwide to develop and test innovative new materials, device structures, and fabrication processes necessary to produce cost-effective PV modules in high volumes. Provide a vibrant forum for interaction among industry and academic experts to address critical challenges in PV module manufacturing. Program scope and project selection established with explicit industry input Create and transfer innovative technologies to industry for development and application in 3-5 years. Bay Area Photovoltaic Consortium 3
Revolutionary Approach Applied research moving technology from university to industry in 3-5 years Technology supporting manufacture of modules at $0.50/W price Premise: Interaction among the leading scientists from both industry and university communities will catalyze generation of the disruptive ideas that can change the face of PV manufacturing in the United States. Bay Area Photovoltaic Consortium 4
Vision Creating PV technology that industry will use. Collaboration Innovation Application Bay Area Photovoltaic Consortium 5
Membership Spans PV Supply Chain Industry Members GE Konica Minolta DuPont Stion 3SUN Total/SunPower AGC Alta Devices Bosch Bandgap Engineering Corning EpiSolar Heliovolt Rose Street Labs Prospective Members Abengoa Applied Materials Coherent Hanwha Solar America Sun Edison REEL Solar Samsung Cheil Solar Junction Solexant Sun Synchrony Bay Area Photovoltaic Consortium 6
Silicon Absorbers and Cells Award Status Sanjay Banerjee Cui Stanford High Efficiency Ultrathin Silicon Solar Cells S. Banerjee Texas Thin Crystalline RPCVD Back Contact Cells Stuart Bowden ASU Laser Wafering van Hest NREL Module Interconnects and Crystalline Film Silicon by Atmospheric Pressure Processing Subramanian Berkeley High -resolution, high -speed printing of PV contacts Photon Management and Transparent Conductors Shanhui Fan and Joel Ager Brongersma Stanford Percolating Transparent Metallic Electrodes for Solar Cells Fan Stanford Theory and simulation of photon management in nanostructured solar cells Wladek/Ager LBNL New Transparent Conducting Oxides Harry Atwater Cal Tech Solar Cell Efficiency Enhancement via Light Trapping in Resonant Dielectric Sphere Arrays Kaustav Banerjee Ning Wu U.C. Santa Barbara Colorado Mines Graphene Electrode Eng. for Photovoltaic Application Large-Area, Fast, and Electric-Field Assisted Continuous Coating for Nanostructured Photon Management Bay Area Photovoltaic Consortium 7
Award Status This Film Absorbers and Cells Hugh Hillhouse Clemens/Bent Stanford Bandgap Grading in Cu2ZnSn(S,Se)4 Solar Cells + SnS based PVs Toney SLAC Advanced Materials Characterization Hanket Delaware Advanced Evaporation Source Design H Hillhouse Washington Development of Multicolor Lock-in PL Method Scott Dunham Washington Fundamental Modeling of Chalcopyrite Solar Cells M Lonergan Oregon Identifying Problem Areas in CIGS and CdTe Based Photovoltaic Devices Colin Wolden Colorado Mines Mike Scarpulla Utah Non-Equilibrium Processing of CdTe Absorbers Laser Processing CdTe: Efficiency & Manufacturing Ferekides USF CdTe Absorbers Milliron LBNL In situ characterization of grain growth in thin film semiconductors Yang Berkeley Applying Cation-Exchange Chemistry to Nanowire Arrays for Efficient Solution- Processed Solar Cells Bay Area Photovoltaic Consortium 8
Award Status High Performance and Multijunction Cells Ali Javey Javey Berkeley High Performance, Low Cost, III V Photovoltaics on Metal Foils Harris Stanford Ultra high efficiency thin film multi-junction solar cell McIntyre Stanford Thin Film Compound Semiconductor Solar Cells via Templated Growth McGehee Stanford Low-Cost Tandem Solar Cells With Greater than 20% Power Conversion Efficiency Yablonovitch Berkeley High Voc Solar Absorbers for High-Efficiency, Spectral-Splitting, Solar Cells Y-H Zhang ASU Si/II-VI double-heterostructure solar cells Buonassisi MIT Design principles and defect tolerances of silicon / III-V multijunction interfaces P Bermel Purdue Exploratory Photovoltaic Modeling and Simulation Encapsulation and Reliability Reinhold Dauskardt Dauskardt Roger French Stanford Reliability and Operational Lifetimes for BAPVC Technologies Case Western PV Module Performance & Lifetime Prediction:Inserting New Technologies Without Lifetime Penalty Segalman/Urban Berkeley Novel polymer-nanocrystal composite barrier layers Bernard Kippelen GIT Tailoring Electrostatic Interactions to Produce Hybrid Barrier Films for Photovoltaics Bay Area Photovoltaic Consortium 9
Laser Wafering Concept Above a critical flux, transparent wavelengths become absorbed Beam can be focused beneath surface to create damage layer Liftoff process implemented to produce kerfless, surface passivized, thin-film silicon wafers
1500 µm BAPVC Advanced Contacts via Gravure printing 12.55 µm Gravure printing: Line width < 10 µm Line-edge roughness < 1 µm. Print speed 10x faster than current PV screen printers Reduced shadowing loss 80% reduction in Ag consumption Research in for Cu substitution High-resolution, high-speed printing of PV contacts, V. Subramanian, Berkeley
Silicon Absorber and Cells Enhancement of Light absorption Shuang Wang, MRS Spring 2013, A12.03
Thin Monocrystalline Si RPCVD Back Contact Cells Thin (<40μm) monocrystalline silicon for material cost reduction thereby reducing $/W Back contact architecture: No front contact, therefore no shading related losses Remote Plasma-enhanced CVD (RPCVD): Less ion bombardment damage (compared to PECVD) leads to improved surface passivation quality Nano-imprint lithography reduces process complexity/cost 13 The University of Texas Microelectronics Research Center
Nanostructured Metals and Semiconductors for Enhanced Solar Energy Harvesting Metal stripes enhance light absorption Exploiting plasmon resonances of metal stripes Coupling to Si waveguide modes Metal nanostructures offer intriguing opportunities for enhancing solar cells Metal nanostructures exhibit a strong, resonant light-matter interaction This interaction is tunable by changing the structure shape, size, environment,.. Metal nanostructures deposition is scalable and low cost Ultimate, best design of nanostructure patterns requires intuition and simulations
Crack Growth Rate, da/dt (m/s) In-situ UV Effects on Barrier Debonding 10-4 Simulated UV Exposure 10-5 10-6 10-7 10-8 10-9 10-10 10-11 UV intensity 1.2 mw/cm 2 No UV da kinetic model G UV intensity tip h ITO v 0.6 mw/cm 2 o sinh dt Glass Substrate 0 1 2 3 4 5 6 7 Strain Energy Release Rate, G (J/m 2 ) G 2 Glass Substrate ITO polysiloxane barrier UV activates new kinetic pathways for debonding threshold load for crack growth dramatically reduced crack growth rate increases with increase in UV intensity
Challenge Slides Near-Term Challenges (1-3 Years) Top near-term challenges in the area of Metrology for c-si photovoltaics as it relates to advanced concepts in university research Where is the photon absorbed? Surface recombination metrology and mechanisms Cell and module reliability
Challenge Slides Long-Term Challenges (4+ Years) Top long-term challenge(s) in the area of Metrology for c-si photovoltaics as it relates to transferring new technologies to industry Cell and module reliability
Thanks jpbenner@stanford.edu 650-213-2596 http://bapvc.stanford.edu/