Advanced optics for CPV

Transcription

1 Advanced optics for CPV P.Zamora, A.Cvetković, M.Buljan, M.Hernandez, P. Benítez, J.C. Miñano, O.Dross, R.Alvarez, A.Santamaría LPI-LLC, USA Universidad Politécnica de Madrid, Spain

2 Outline 1. The fundamental limitations on concentration 2. The tolerance angle budget 3. How advanced optical design can help you: three examples 4. Conclusions 2/28

3 Acceptance angle-concentration trade-off 2α 2α CAP=Concentration acceptance product Fresnel lens CAP= C sinα n n =1 (air), n 1.5 (practical materials) Optically, we would like: Make CAP as high as possible Cell 3/28

4 Outline 1. The fundamental limitations on concentration 2. The tolerance angle budget 3. How advanced optical design can help you: three examples 4. Conclusions 4/28

5 Do you need more tolerance? Symptomatology: 1. Optics surfaces require high accuracy 2. Assembling is expensive because fine adjustments become compulsory. 3. Efficiency decreases significantly from single unit to array. Optical mismatch 4. Efficiency increases significantly when cells are bigger. 5. The electricity production waves in moderate windy conditions 6. Soiling decreases efficiency more strongly than in flat modules 5/28

6 Tolerance budget distribution Example: Design acceptance half-angle α = 1 deg Design acceptance angle α = 1 deg Module accep. angle α = 0.39 deg Array accep. angle α = 0.08 deg 1.0º 0.9º 0.8º 0.7º 0.6º 0.5º 0.4º 0.3º 0.2º 0.1º 0.0º design acceptance angle= 1 deg acceptance angle= acceptance 0.74 deg angle= 0.62 deg module acceptance angle= 0.39 deg array accep. angle= 0.08º 6/28

7 Outline 1. The fundamental limitations on concentration 2. The tolerance angle budget 3. How advanced optical design can help you: three examples 4. Conclusions 7/28

8 Advanced HCPV optics: Free-form designs Free-form: surfaces with no prescribed symmetry New degrees of freedom to the design: A single optical element can perform multiple functions The SMS 3D design method of Nonimaging Optics is the most advanced method to design free-forms 8/28

9 Non uniform irradiance problem Irradiance (x,y) is uniform Intensity (α) is non uniform Primary lens Irradiance (x,y) is non uniform Intensity (α) is ~ uniform Focal plane Cell efficiency is sensitive to irradiance non-uniformities Goal: uniform irradiance on the cell 9/28

10 Classic solution to solve the nonuniform irradiance on the cell α Prism homogenizer 10/28

11 Free-form XR for HCPV (Boeing-LPI) Free-form mirror Glass cover Free-form lens A. Cvetkovic, M. Hernández, P. Benítez, J. C. Miñano, J. Schwartz, A. Plesniak, R. Jones, D. Whelan, The Free Form XR Photovoltaic Concentrator: a High Performance SMS3D Design, Proc. SPIE Vol , 2008 A. Plesniak et al. Demostration of high performance concentrating photovoltaic module designs for utility scale power generation, ICSC 5, (Palm Desert, CA, USA, 2008) C g = 1,000x α = 1.8º Irr max = 907 suns Eff opt =81% Current (A) Irradiance distribution on the cell I SC 8.2 A V OC 17.8 V Pmpp W η DC 29.1 % FF 79.2 % DNI 854 W/m 2 T AMBIENT 27.8 C Date Jan Time 14:00:10 Boeing-LPI free-form lens Voltage (V) cell side Further details to be presented at A. Plesniak et al. Demostration of high cell side performance concentrating photovoltaic module designs for utility scale power generation, 34th IEEE PVSC, (Philadelphia, PA, USA, 2009) 11/28

12 Non uniform irradiance problem is common to illumination optics. Peaked irradiance on the target 12/28

13 Kohler integrator arrays in illumination optics Smooth irradiance on the target 13/28

14 An LPIs SMS design with Köhler integration: 2D aspheric integrator arrays. The condenser lenses and the Köhler array is all in a single dielectric piece!!! Smooth irradiance on the target 14/28

15 Köhler integrator in Solar: (James, Sandia Labs. 1990) Excellent uniformity!!! Poor acceptance at moderate to high C Very deep POE SOE Solar cell 15/28

16 Fresnel-R free-form Köhler design Primary lens (R) 3D Köhler integration Optical surfaces split into 4 free-form sectors Secondary lens (R) Solar cell A. Cvetkovic et al. High Performance Köhler Concentrators with Uniform Irradiance on Solar Cell, ICSC 5, (Palm Desert, CA, USA, 2008) 16/28

17 Rotational symmetric vs. LPI free-form design Design parameters (both cases) C g = 510x f = 384 mm f # = 1.2 Cell = 10 x 10 mm POE SOE dome Solar cell rotational design SOE LPI design Solar cell Patent pending 17/28

18 Rotational symmetric vs. LPI free-form design C g = 510x f = 384 mm f #= 1.2 Relative efficiency 100% 90% 80% 70% average irradiance 450 DNI 850W/m2 60% rotational design α = ± 0.63º Eff opt = 88.22% Peak irradiance = 3100 suns Angle (deg) LPI design α= ± 1.47º Eff opt = 88% Peak irradiance = 484 suns 18/28

19 Rotational symmetric vs. LPI free-form design rotational design SOE Peak irradiance = 3100 suns LPI design SOE Peak irradiance = 484 suns 19/28

20 XXR free-form Köhler design 3D Köhler integration Optical surfaces split into 4 free-form sectors Tertiary lens 4b 3b 1b 2b Secondary mirror 4a 3a 1a Tertiary lens Primary mirror 2a 20/28

21 XXR free-form Köhler design Cg= 2,070x α= ± 0.85º Peak Irradiance 2236suns 100% Relative efficiency 90% 80% 70% 60% 50% 40% 30% 20% % 0% Angle (º) Transmission curve Irradiance diagram 21/28

22 XXR free-form Köhler design vs. aplanatic design SOE SOE POE HOMOGENIZING PRISM SOLAR CELL SOLAR CELL TOE Aplanatic design Cg= 850x α = ± 0.85º XXR free-form Köhler Cg= 2070x α = ± 0.85º 22/28

23 Outline 1. The fundamental limitations on concentration 2. The tolerance angle budget 3. How advanced optical design can help you: two examples 4. Conclusions 23/28

24 Conclusions 1. The tolerance budget must be spent among the different components of the CPV for a cost effective solution. 2. There is no such trade-off between acceptance angle and efficiency, both things are achievable and are necessary for a cost effective system 3. Advanced optical designs can give you more tolerance, very uniform irradiance, more efficiency and simpler assembling with no extra elements and no extra cost. 24/28

25 LEGAL NOTICE Devices shown in this presentation are protected by the following US and International Patents and Patents Pending: Patents Issued HIGH EFFICIENY NON-IMAGING US 6,639,733 October 28, 2003 COMPACT FOLDED-OPTICS ILLUMINATION LENS US 6,896,381 May 24, 2005 COMPACT FOLDED-OPTICS ILLUMINATION LENS US 7,152,985 December 26, 2006 COMPACT FOLDED-OPTICS ILLUMINATION LENS US 7,181,378 February 20, 2007 DEVICE FOR CONCENTRATING OR COLLIMATING RADIANT ENERGY US 7,160,522 January 9, 2007 DISPOSITIVO CON LENTE DISCONTINUA DE REFLEXIÓN TOTAL INTERNA Y DIÓPTRICO ESFÉRICO PARA CONCENTRACIÓN O COLIMACIÓN DE ENERGÍA RADIANTE Spain ES P December 2, 1999 OPTICAL MANIFOLD FOR LIGHT-EMITTING DIODES US 7,380,962 OPTICAL MANIFOLD FOR LIGHT-EMITTING DIODES US 7,286,296 THREE-DIMENSIONAL SIMULTANEOUS MULTIPLE-SURFACE METHOD AND FREE-FORM ILLUMINATION- OPTICS DESIGNED THEREFROM US 7,460,985 December 2, 2008 Partial List of Patents Pending DEVICE FOR CONCENTRATING OR COLLIMATING RADIANT ENERGY - a continuation of US 7,160,522 FREE-FORM LENTICULAR OPTICAL ELEMENTS AND THEIR APPLICATION TO CONDENSERS AND HEADLAMPS PCT/US2006/ July 28, 2006 MULTI-JUNCTION SOLAR CELLS WITH A HOMOGENIZER SYSTEM AND COUPLED NON-IMAGING LIGHT CONCENTRATOR PCT/US07/63522 March 7, 2007 OPTICAL CONCENTRATOR, ESPECIALLY FOR SOLAR PHOTOVOLTAICS PCT/US08/03439 Mar 14, /28

26 Acknowledgements The authors acknowledge partial support from IMADE within the project PIE521/2008, Investigación en nuevos concentradores FV 1000x con células solares de alta eficiencia 26/28

27 Contacts LPI Roberto Alvarez, CEO Waqidi Falicoff, Exec. VP 2400 Lincoln Ave. Altadena, CA 91001, USA Fax: (949) LPI EUROPE Ramón F. de Caleya, Managing Director Oliver Dross, Technology Director Edificio Cedint Campus de Montegancedo UPM 28223, Madrid, SPAIN Fax: (+34) LPI PO Bill Tse, General Manager Unit 02, G/F, Photonics Centre, Science Park East Ave., Hong-Kong, CHINA Fax: /28

28 LPI Overview LPI-LLC Headquarters Altadena, California, USA LPI-Europe Cologne, Germany Madrid, Spain LPI-PO Hong Kong, China Thank you! 28/28

29 Presenter contact information: CEDINT- Universidad Politecnica de Madrid Aleksandra Cvetkovic Tel: /28