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Tracking-integrated systems for concentrating photovoltaics

Abstract

Concentrating photovoltaic (CPV) systems, which use optical elements to focus light onto small-area solar cells, have the potential to minimize the costs, while improving efficiency, of photovoltaic technology. However, CPV is limited by the need to track the apparent motion of the Sun. This is typically accomplished using high-precision mechanical trackers that rotate the entire module to maintain normal light incidence. These machines are large, heavy and expensive to build and maintain, deterring commercial interest and excluding CPV from the residential market. To avoid this issue, some attention has recently been devoted to the development of tracking-integrated systems, in which tracking is performed inside the CPV module itself. This creates a compact system geometry that could be less expensive and more suitable for rooftop installation than existing CPV trackers. We review the basic tracking principles and concepts exploited in these systems, describe and categorize the existing designs, and discuss the potential impact of tracking integration on CPV cost models and commercial potential.

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Figure 1: PV technologies.
Figure 2: Beam steering.
Figure 3: Focus-on-cell tracking-integrated systems.
Figure 4: Micro- and self-tracking based on confinement in a waveguide or cavity.
Figure 5: Summary of tracking-integrated concentrator designs.

References

  1. Photovoltaics Report (Fraunhofer-Institut für Solare Energiesysteme, 2015); http://go.nature.com/bbCJU5

  2. Electricity Information 2015 (International Energy Agency, 2015); http://go.nature.com/Sf38pE

  3. Shah, V. & Booream-Phelps, J. Crossing the Chasm: Solar Grid Parity in a Low Oil Price Era (Deutsche Bank, 2015); http://go.nature.com/FjJA67

    Google Scholar 

  4. Philipps, S., Bett, A., Horowitz, K. & Kurtz, S. Current Status of Concentrator Photovoltaic (CPV) Technology (NREL, 2015); http://go.nature.com/BJ4x38

    Book  Google Scholar 

  5. Swanson, R. M. The promise of concentrators. Prog. Photovoltaics 8, 93–111 (2000).

    Article  Google Scholar 

  6. MacMillan, H. et al. 28% efficient GaAs concentrator solar cells. In Conference Record of the Twentieth IEEE 462–468 (IEEE, 1988).

    Chapter  Google Scholar 

  7. James, L. & Moon, R. GaAs concentrator solar cell. Appl. Phys. Lett. 26, 467–470 (1975).

    Article  Google Scholar 

  8. Yamaguchi, M. III–V compound multi-junction solar cells: present and future. Sol. Energy Mater. Sol. Cells 75, 261–269 (2003).

    Article  Google Scholar 

  9. New world record for solar cell efficiency at 46%. Fraunhofer ISE (1 December 2014); http://go.nature.com/DB4w6q

  10. McGehee, M. An Overview of Solar Cell Technology (Stanford University, 2011); http://go.nature.com/543x7k

    Google Scholar 

  11. Kurtz, S. Opportunities and challenges for development of a mature concentrating photovoltaic power industry. Contract 303, 275–3000 (2012).

    Google Scholar 

  12. Sunpower C7 Tracker Datasheet (Sunpower, 2012); http://go.nature.com/vyfa2x

  13. Kayes, B. M. et al. 27.6% Conversion efficiency, a new record for single-junction solar cells under 1 sun illumination. In 37th IEEE Photovoltaic Specialists Conference (PVSC) 000004–000008 (IEEE, 2011).

    Google Scholar 

  14. Yablonovitch, E., Miller, O. D. & Kurtz, S. R. The opto-electronic physics that broke the efficiency limit in solar cells. In 38th IEEE Photovoltaic Specialists Conference (PVSC) 001556–001559 (IEEE, 2012).

    Google Scholar 

  15. Lee, K., Zimmerman, J. D., Hughes, T. W. & Forrest, S. R. Non-destructive wafer recycling for low-cost thin-film flexible optoelectronics. Adv. Funct. Mater. 24, 4284–4291 (2014).

    Article  Google Scholar 

  16. Lee, K., Lee, J., Mazor, B. A. & Forrest, S. R. Transforming the cost of solar-to-electrical energy conversion: integrating thin-film GaAs solar cells with non-tracking mini-concentrators. Light Sci. Appl. 4, e288 (2015).

    Article  Google Scholar 

  17. Zagolla, V., Tremblay, E. & Moser, C. Proof of principle demonstration of a self-tracking concentrator. Opt. Express 22, A498–A510 (2014). This work demonstrates a planar micro-optic concentrator with reactive tracking achieved using a paraffin wax actuator.

    Article  Google Scholar 

  18. Haysom, J. E., Jafarieh, O., Anis, H., Hinzer, K. & Wright, D. Learning curve analysis of concentrated photovoltaic systems. Prog. Photovoltaics 23, 1678–1686 (2014).

    Article  Google Scholar 

  19. Miles, R., Hynes, K. & Forbes, I. Photovoltaic solar cells: an overview of state-of-the-art cell development and environmental issues. Prog. Cryst. Growth Ch. 51, 1–42 (2005).

    Article  Google Scholar 

  20. Winston, R., Miñano, J. C. & Benitez, P. G. Nonimaging Optics (Academic, 2005).

    MATH  Google Scholar 

  21. Smestad, G., Ries, H., Winston, R. & Yablonovitch, E. The thermodynamic limits of light concentrators. Sol. Energy Mater. 21, 99–111 (1990).

    Article  Google Scholar 

  22. Winston, R. & Zhang, W. Pushing concentration of stationary solar concentrators to the limit. Opt. Express 18, A64–A72 (2010).

    Article  Google Scholar 

  23. van Sark, W. G. et al. Luminescent solar concentrators - a review of recent results. Opt. Express 16, 21773–21792 (2008).

    Article  Google Scholar 

  24. Giebink, N. C., Wiederrecht, G. P. & Wasielewski, M. R. Resonance-shifting to circumvent reabsorption loss in luminescent solar concentrators. Nature Photon. 5, 694–701 (2011).

    Article  Google Scholar 

  25. Marion, W. & Wilcox, S. Solar Radiation Data Manual for Flat-Plate and Concentrating Collectors (NREL, 1994); http://go.nature.com/qIRONy

    Google Scholar 

  26. Luque-Heredia, I. in Next Generation of Photovoltaics (eds Cristobal, A., Martí Vega, A. & Luque López, A. ) 61–93 (Springer, 2012).

    Book  Google Scholar 

  27. Smith, S. & Shiao, M. Solar PV Balance of System (BOS) Markets: Technologies, Costs and Leading Companies, 2013–2016 (Green Tech Media, 2012); http://go.nature.com/lX3UdI

    Google Scholar 

  28. Angel, R., Cuerden, B. & Whiteside, A. Lightweight dual-axis tracker designs for dish-based HCPV. AIP Conf. Proc. 1616, 220 (2014).

    Article  Google Scholar 

  29. Bushong, S. Q&A with Mechatron, manufacturer of large solar trackers. Solar Power World (17 December 2014); http://go.nature.com/dkwCoy

  30. Kann, S. U. S. Solar Market Insight Report 2015 Q2 (Green Tech Media, 2015); http://go.nature.com/JfjJMD

    Google Scholar 

  31. Abdallah, S. & Nijmeh, S. Two axes Sun tracking system with PLC control. Energy Convers. Manage. 45, 1931–1939 (2004).

    Article  Google Scholar 

  32. Mousazadeh, H. et al. A review of principle and Sun-tracking methods for maximizing solar systems output. Renew. Sust. Energy Rev. 13, 1800–1818 (2009).

    Article  Google Scholar 

  33. León, N., García, H. & Ramírez, C. Semi-passive solar tracking concentrator. Energy Procedia 57, 275–284 (2014). This work reports beam steering using rotating mirrors.

    Article  Google Scholar 

  34. León, N., Ramírez, C. & García, H. Rotating prism array for solar tracking. Energy Procedia 57, 265–274 (2014).

    Article  Google Scholar 

  35. García, H., Ramírez, C. & León, N. Innovative solar tracking concept by rotating prism array. Int. J. Photoenergy 2014, 807159 (2014). This study shows ray-trace simulation of beam steering with a rotating prism array.

    Article  Google Scholar 

  36. Teng, T.-C. & Lai, W.-C. Planar solar concentrator featuring alignment-free total-internal-reflection collectors and an innovative compound tracker. Opt. Express 22, A1818–A1834 (2014).

    Article  Google Scholar 

  37. Pender, J. G. Motion-free tracking solar concentrator. US patent 6958868 B1 (2005).

  38. Duston, D., Haddock, J., Kokonaski, W., Blum, R. & Colbert, D. Method for light ray steering. US patent 20070157924 A1 (2007).

  39. Valyukh, S., Valyukh, I. & Chigrinov, V. Liquid-crystal based light steering optical elements. Photon. Lett. Pol. 3, 88–90 (2011).

    Google Scholar 

  40. Cheng, J., Park, S. & Chen, C.-L. Optofluidic solar concentrators using electrowetting tracking: concept, design, and characterization. Sol. Energy 89, 152–161 (2013).

    Article  Google Scholar 

  41. Cheng, J. & Chen, C.-L. Adaptive beam tracking and steering via electrowetting-controlled liquid prism. Appl. Phys. Lett. 99, 191108 (2011).

    Article  Google Scholar 

  42. Narasimhan, V., Jiang, D. & Park, S.-Y. Design and optical analyses of an arrayed microfluidic tunable prism panel for enhancing solar energy collection. Appl. Energy 162, 450–459 (2016). This work proposes optical beam steering using liquid prisms controlled by electrowetting, and reports simulations of full hemispheric tracking range.

    Article  Google Scholar 

  43. Kotsidas, P., Chatzi, E. & Modi, V. Stationary nonimaging lenses for solar concentration. Appl. Optics 49, 5183–5191 (2010). This paper reports a wide-acceptance lens (±30° and ±60°) with a PV cell moving on a curved path to track the focal spot.

    Article  Google Scholar 

  44. Kotsidas, P., Modi, V. & Gordon, J. M. Nominally stationary high-concentration solar optics by gradient-index lenses. Opt. Express 19, 2325–2334 (2011). This study shows a ±60° acceptance lens moved on a semi-circular path for Sun tracking, with a stationary solar cell.

    Article  Google Scholar 

  45. Duerr, F., Meuret, Y. & Thienpont, H. Tailored free-form optics with movement to integrate tracking in concentrating photovoltaics. Opt. Express 21, A401–A411 (2013).

    Article  Google Scholar 

  46. Duerr, F., Benítez, P., Miñano, J. C., Meuret, Y. & Thienpont, H. Integrating tracking in concentrating photovoltaics using non-rotational symmetric laterally moving optics. Proc. SPIE 8124, 81240M (2011).

    Article  Google Scholar 

  47. Sweatt, W. et al. Micro-optics for high-efficiency optical performance and simplified tracking for concentrated photovoltaics (CPV). In International Optical Design Conference 2010 ITuC4 (OSA, 2010).

    Google Scholar 

  48. Price, J. S., Sheng, X., Meulblok, B. M., Rogers, J. A. & Giebink, N. C. Wide-angle planar microtracking for quasi-static microcell concentrating photovoltaics. Nature Commun. 6, 6223 (2015). This work shows a refractive–reflective double optic with ±60° tracking range; and tracking done via micromechanical side-to-side translations.

    Article  Google Scholar 

  49. Karp, J. H. & Ford, J. E. Planar micro-optic solar concentration using multiple imaging lenses into a common slab waveguide. Proc. SPIE 7407, 74070D (2009).

    Article  Google Scholar 

  50. Karp, J. H., Tremblay, E. J. & Ford, J. E. Planar micro-optic solar concentrator. Opt. Express 18, 1122–1133 (2010).

    Article  Google Scholar 

  51. Hallas, J. M., Baker, K. A., Karp, J. H., Tremblay, E. J. & Ford, J. E. Two-axis solar tracking accomplished through small lateral translations. Appl. Optics 51, 6117–6124 (2012). This paper reports a planar micro-optic concentrator with micromechanical tracking via side-to-side translation of the waveguide.

    Article  Google Scholar 

  52. Hallas, J. M., Karp, J. H., Tremblay, E. J. & Ford, J. E. Lateral translation micro-tracking of planar micro-optic solar concentrator. Proc. SPIE 7769, 776904 (2010).

    Article  Google Scholar 

  53. Karp, J. H., Tremblay, E. J., Hallas, J. M. & Ford, J. E. Orthogonal and secondary concentration in planar micro-optic solar collectors. Opt. Express 19, A673–A685 (2011).

    Article  Google Scholar 

  54. Liu, C., Wang, Q.-H. & Wang, M.-H. Mirror reflector actuated by liquid droplet. Photon. Technol. Lett. 26, 1077–1080 (2014).

    Article  Google Scholar 

  55. Ma, H. & Wu, L. Horizontally staggered lightguide solar concentrator with lateral displacement tracking for high concentration applications. Appl. Optics 54, 6217–6223 (2015).

    Article  Google Scholar 

  56. Unger, B. L., Schmidt, G. R. & Moore, D. T. Dimpled planar lightguide solar concentrators. In International Optical Design Conference ITuE5P (OSA, 2010).

    Google Scholar 

  57. Wu, H.-Y. & Chu, S.-C. Ray-leakage-free sawtooth-shaped planar lightguide solar concentrators. Opt. Express 21, 20073–20089 (2013).

    Article  Google Scholar 

  58. Liu, Y., Huang, R. & Madsen, C. K. Two-axis tracking using translation stages for a lens-to-channel waveguide solar concentrator. Opt. Express 22, A1567–A1575 (2014).

    Article  Google Scholar 

  59. Selimoglu, O. & Turan, R. Exploration of the horizontally staggered light guides for high concentration CPV applications. Opt. Express 20, 19137–19147 (2012).

    Article  Google Scholar 

  60. Tsou, Y.-S., Chang, K.-H. & Lin, Y.-H. A droplet manipulation on a liquid crystal and polymer composite film as a concentrator and a Sun tracker for a concentrating photovoltaic system. J. Appl. Phys. 113, 244504 (2013).

    Article  Google Scholar 

  61. Klotz, F. et al. Field test results of the Archimedes Photovoltaic V-Trough concentrator system. In Proc. 17th European Photovoltaic Solar Energy Conference and Exhibition 492–495 (ETA-Florence and WIP-Munich, 2001).

    Google Scholar 

  62. Clifford, M. & Eastwood, D. Design of a novel passive solar tracker. Sol. Energy 77, 269–280 (2004).

    Article  Google Scholar 

  63. Baker, K. A., Karp, J. H., Tremblay, E. J., Hallas, J. M. & Ford, J. E. Reactive self-tracking solar concentrators: concept, design, and initial materials characterization. Appl. Optics 51, 1086–1094 (2012).

    Article  Google Scholar 

  64. Tremblay, E. J., Loterie, D. & Moser, C. Thermal phase change actuator for self-tracking solar concentration. Opt. Express 20, A964–A976 (2012).

    Article  Google Scholar 

  65. Zagolla, V., Dominé, D., Tremblay, E. & Moser, C. Self-tracking solar concentrator with an acceptance angle of 32°. Opt. Express 22, A1880–A1894 (2014).

    Article  Google Scholar 

  66. Kozodoy, P. et al. Self-tracking concentrator for photovoltaics. In CLEO: Applications and Technology ATu2J.1 (OSA, 2015).

    Google Scholar 

  67. Zagolla, V., Tremblay, E. & Moser, C. Efficiency of a micro-bubble reflector based, self-adaptive waveguide solar concentrator. Proc. SPIE 8620, 862010 (2013).

    Article  Google Scholar 

  68. Zagolla, V., Tremblay, E. & Moser, C. Light induced fluidic waveguide coupling. Opt. Express 20, A924–A931 (2012).

    Article  Google Scholar 

  69. Schmaelzle, P. H., Whiting, G. L., Martini, J., Fork, D. K. & Maeda, P. Y. Solar energy harvesting device using stimuli-responsive material. US patent 20120132255 A1 (2014).

  70. Peters, M., Goldschmidt, J. C., Kirchartz, T. & Bläsi, B. The photonic light trap—improved light trapping in solar cells by angularly selective filters. Sol. Energy Mater. Sol. Cells 93, 1721–1727 (2009).

    Article  Google Scholar 

  71. Polman, A. & Atwater, H. A. Photonic design principles for ultrahigh-efficiency photovoltaics. Nature Mater. 11, 174–177 (2012).

    Article  Google Scholar 

  72. Kosten, E. D., Atwater, J. H., Parsons, J., Polman, A. & Atwater, H. A. Highly efficient GaAs solar cells by limiting light emission angle. Light Sci. Appl. 2, e45 (2013).

    Article  Google Scholar 

  73. Stefancich, M. et al. Optofluidic approaches to stationary tracking optical concentrator systems. Proc. SPIE 8834, 88340C (2013).

    Article  Google Scholar 

  74. Apostoleris, H., Stefancich, M., Lilliu, S. & Chiesa, M. Sun-tracking optical element realized using thermally activated transparency-switching material. Opt. Express 23, A930–A935 (2015).

    Article  Google Scholar 

  75. Apostoleris, H. N., Chiesa, M. & Stefancich, M. Self-tracking concentrator based on switchable transparency and rejected-ray recycling. Proc. SPIE 9572, 95720A (2015). This paper reports simulations for a mid-concentration ray-recycling concentrator using transparency-switching material with a moving aperture to trap light.

    Article  Google Scholar 

  76. Maragliano, C., Chiesa, M. & Stefancich, M. Point-focus spectral splitting solar concentrator for multiple cells concentrating photovoltaic system. Preprint at http://arxiv.org/abs/1504.00258 (2015).

  77. Jones, J. Global PV Pricing Outlook (Green Tech Media, 2015); http://go.nature.com/YY8JBH

    Google Scholar 

  78. Horowitz, K., Woodhouse, M., Lee, H. & Smestad, G. Bottom-up Cost Analysis of a High Concentration PV Module (NREL, 2015); http://www.nrel.gov/docs/fy15osti/63947.pdf

    Book  Google Scholar 

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The authors thank Maritsa Kissamitaki for the preparation of the figures.

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Apostoleris, H., Stefancich, M. & Chiesa, M. Tracking-integrated systems for concentrating photovoltaics. Nat Energy 1, 16018 (2016). https://doi.org/10.1038/nenergy.2016.18

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