Night time performance of a storage integrated solar thermophotovoltaic (SISTPV) system

Abstract Energy storage at low maintenance cost is one of the key challenges for generating electricity from the solar energy. This paper presents the theoretical analysis (verified by CFD) of the night time performance of a recently proposed conceptual system that integrates thermal storage (via phase change materials) and thermophotovoltaics for power generation. These storage integrated solar thermophotovoltaic (SISTPV) systems are attractive owing to their simple design (no moving parts) and modularity compared to conventional Concentrated Solar Power (CSP) technologies. Importantly, the ability of high temperature operation of these systems allows the use of silicon (melting point of 1680 K) as the phase change material (PCM). Silicon’s very high latent heat of fusion of 1800 kJ/kg and low cost ($1.70/kg), makes it an ideal heat storage medium enabling for an extremely high storage energy density and low weight modular systems. In this paper, the night time operation of the SISTPV system optimised for steady state is analysed. The results indicate that for any given PCM length, a combination of small taper ratio and large inlet hole-to-absorber area ratio are essential to increase the operation time and the average power produced during the night time. Additionally, the overall results show that there is a trade-off between running time and the average power produced during the night time. Average night time power densities as high as 30 W/cm 2 are possible if the system is designed with a small PCM length (10 cm) to operate just a few hours after sun-set, but running times longer than 72 h (3 days) are possible for larger lengths (50 cm) at the expense of a lower average power density of about 14 W/cm 2 . In both cases the steady state system efficiency has been predicted to be about 30%. This makes SISTPV systems to be a versatile solution that can be adapted for operation in a broad range of locations with different climate conditions, even being used off-grid and in space applications.

[1]  Taketoshi Hibiya,et al.  Thermophysical properties data on molten semiconductors , 1992 .

[2]  Carlos Algora,et al.  Detailed balance analysis of solar thermophotovoltaic systems made up of single junction photovoltaic cells and broadband thermal emitters , 2010 .

[3]  K. W. Stone,et al.  On-Sun test results of McDonnell Douglas' prototype solar thermophotovoltaic power system , 1994, Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC).

[4]  Robin K. Huang,et al.  Hybrid Back Surface Reflector GaInAsSb Thermophotovoltaic Devices , 2004 .

[5]  E. F. Leingang,et al.  Solar thermophotovoltaic power experiments at McDonnell Douglas , 1994 .

[6]  Anthony Catalano.  Thermophotovoltaics: A new paradigm for power generation? , 1996 .

[7]  David M. Wilt,et al.  System performance of a solar thermophotovoltaic system for space and terrestrial application , 1995 .

[8]  Philip C. Eames,et al.  Natural convection in an internally finned phase change material heat sink for the thermal management of photovoltaics , 2011 .

[9]  Chie Gau,et al.  Melting and solidification of a metal system in a rectangular cavity , 1984 .

[10]  Antonio Martí,et al.  Absolute limiting efficiencies for photovoltaic energy conversion , 1994 .

[11]  C. K. Hsieh,et al.  Exact solutions of Stefan problems for a heat front moving at constant velocity in a quasi-steady state , 1995 .

[12]  D. Brüggemann,et al.  Shell-and-tube type latent heat thermal energy storage: numerical analysis and comparison with experiments , 2011 .

[13]  Kenneth W. Stone,et al.  Testing and modeling of a solar thermophotovoltaic power system , 2008 .

[14]  Ananthanarayanan Veeraragavan,et al.  Steady state analysis of a storage integrated solar thermophotovoltaic (SISTPV) system , 2013 .

[15]  M. Wanlass,et al.  Monolithic Interconnected Modules (Mims) for Thermophotovoltaic Energy Conversion , 2013 .

[16]  Edwards Afb,et al.  Molten Boron Phase-Change Thermal Energy Storage: Containment and Applicability to Microsatellites , 2011 .

[17]  Kai Sirén,et al.  Analytical model for melting in a semi-infinite PCM storage with an internal fin , 2003 .

[18]  David M. Bierman,et al.  A nanophotonic solar thermophotovoltaic device. , 2014, Nature nanotechnology.

[19]  Cole Boulevard,et al.  Review of Mid- to High- Temperature Solar Selective Absorber Materials , 2002 .

[20]  Donald L. Chubb,et al.  Solar thermophotovoltaic (STPV) system with thermal energy storage , 2008 .

[21]  C. Wang,et al.  LM-04 K 041 June 9 , 2004 Hybrid Back Surface Reflector GaInAsSb Thermophotovoltaic Devices , 2004 .

[22]  A. D. Solomon,et al.  Mathematical Modeling Of Melting And Freezing Processes , 1992 .

[23]  H. Queisser,et al.  Detailed Balance Limit of Efficiency of p‐n Junction Solar Cells , 1961 .

[24]  S. D. Link,et al.  Greater than 20% radiant heat conversion efficiency of a thermophotovoltaic radiator/module system using reflective spectral control , 2004, IEEE Transactions on Electron Devices.

[25]  Thomas Bauer,et al.  Thermophotovoltaics: Basic Principles and Critical Aspects of System Design , 2011 .

[26]  Vaughan R Voller,et al.  ENTHALPY-POROSITY TECHNIQUE FOR MODELING CONVECTION-DIFFUSION PHASE CHANGE: APPLICATION TO THE MELTING OF A PURE METAL , 1988 .

[27]  Carlos Algora del Valle,et al.  Global optimization of solar thermophotovoltaic systems , 2013 .

[28]  S. Argyropoulos,et al.  Mathematical modelling of solidification and melting: a review , 1996 .