Performance characteristics and parametric choices of a solar thermophotovoltaic cell at the maximum efficiency
Graphical abstract
The overall model of the solar thermophotovoltaic cell (STPVC) composed of an optical lens, an absorber, an emitter, and a photovoltaic (PV) cell with an integrated back-side reflector is updated to include various irreversible losses.
Introduction
Thermophotovoltaic cell (TPVC) is a high efficient energy conversion device that can converts a part of radiation heat into electricity. TPVC systems have several performance advantages over other heat conversion systems, including available fuel sources, no moving parts, low noise, and high reliability [1], [2], [3], [4]. TPVCs increasingly play a part in efficiently distributed power generation systems based on pollution-free as well as energy conservation [5], [6], [7], [8], [9]. In the previous researches, thermophotovoltaic (TPV) devices carry out a direct heat-to-electricity conversion by employing photovoltaic (PV) cells [10], [11]. In some experiments, the TPV devices consist of a SiC emitter as well as a single junction TPV cell employing the materials of InGaAs (0.6 eV), GaSb (0.74 eV), or InGaAsSb (0.53 eV) compounds [12], [13], [14]. Specifically, for low-temperature TPV applications, compared with GaSb cells, the efficiency of the system will be enhanced by using InGaAsSb (0.53 eV) cells [15].
The performance of the conventional PV cells is influenced by thermalization losses because it just converts a part of solar energy within some specified frequency ranges into electricity [16]. Based on this problem, the solar thermophotovoltaic (STPV) systems consisting of the solar concentrator, absorber, emitter, and photovoltaic (PV cell) have been proposed and investigated [17], [18], [19], [20], [21], [22], [23], [24], [25], [26], [27], [28], [29]. The intermediate elements, the absorber and emitter, first convert the concentrated solar light into thermal radiation and then emit photonic energy to the PV cell to generate electricity [21]. Compared with the conventional PV cells, an STPV system can efficiently utilize the solar energy because the spectral feature of photons emitted from the emitter corresponds to the bandgaps of solar cells in the system by controlling the emitter temperature.
In order to reduce the radiation and reflection losses of absorber, the area of the absorber is designed to be smaller than that of the emitter whose surface is painted a layer of material to reduce radiation. What is the optimal value of the area ratio of the absorber to the emitter? The solution of this important problem can make STPV systems achieve a high efficiency and a large output power density within reasonable hot-side temperature limits (1500 °C).
In the present paper, we propose a novel model of the STPVC system composed of an optical lens, an absorber, an emitter, a PV cell with an integrated back-side reflector (BSR). The power output and efficiency of the system are derived. The performance characteristics at the maximum efficiency are revealed. The effects of several parameters on the systemic performance, such as the voltage output of the PV cell, the absorber-to-emitter area ratio, the concentration factor, and the band-gap of the semiconductor material are discussed. The results obtained here may be used to guide the design of practical STPVCs.
Section snippets
Model description
A schematic diagram of the solar thermophotovoltaic cell (STPVC) consisting of an optical lens, an absorber, an emitter, and a PV cell with integrated back surface reflector (BSR) is shown in Fig. 1, where the rotating parabolic optical concentrator with lower cost is used, compared with the expensive Fresnel lens which is difficult to be fabricated and easy to be of deformation during the long-term use [16]. TE, TC, and TL are, respectively, the temperatures of the emitter, PV cell, and
Power output and efficiency of an STPVC
When the optical lens focuses the broad solar spectrum on the absorber, which is transferred to the emitter to convert into narrowband thermal emission matched closely to the narrow band-gap of the PV cell [25]. The infrared photons are then absorbed by the PV cell that simultaneously excites electron-hole pairs. These electrons generated in the PV are extracted to transfer to the external load to produce the power output.
According to Fig. 1 and the first law of thermodynamics, we can obtain
Performance characteristics at the maximum efficiency
Eqs. (10), (11) clearly show that the power output and efficiency of the STPVC closely depend on a set of designing and operating parameters such as the concentration ratio C of the optical lens, the front surface areas AA and AE of the absorber and emitter, the temperatures TE and TC of the emitter and the PV cell, the current density J and voltage output V of the PV cell, the band-gap energy Eg of the semiconductor in the PV cell, and so on. In the following discussion, a new parameter, i.e.,
Conclusions
We have established a new model of the STPVC system consisting of an optical lens, an absorber, an emitter, and a PV cell and carried out a concrete analysis for the whole performance of the system. The efficiency of the system can be optimized simultaneously with respect to the voltage output V of the PV cell, the area ratio S of the absorber to the emitter, and the band-gap energy Eg of semiconductor materials in the PV cell, while the power output density can be only optimized with respect
Acknowledgments
This work has been supported by the National Natural Science Foundation (No. 11405142), People’s Republic of China.
References (36)
- et al.
Investigation of the potential of thermophotovoltaic heat recovery for the Turkish industrial sector
Energ Convers Manage
(2013) - et al.
Mathematical modeling of synthesis gas fueled electrochemistry and transport including H2/CO co-oxidation and surface diffusion in solid oxide fuel cell
J Power Sources
(2015) - et al.
A review on the selection of anode materials for solid-oxide fuel cells
Renew Sust Energ Rev
(2015) - et al.
Properties and development of Ni/YSZ as an anode material in solid oxide fuel cell: a review
Renew Sust Energy Rev
(2014) - et al.
Cathode-supported tubular solid oxide fuel cell technology: a critical review
J Power Sources
(2013) - et al.
Prospects for high-performance thermophotovoltaic conversion efficiencies exceeding the Shockley-Queisser limit
Energ Convers Manage
(2015) - et al.
Performance evaluation and parametric optimum design of a molten carbonate fuel cell-thermophotovoltaic cell hybrid system
Energy Convers Manage
(2016) - et al.
Radiant thermal conversion in 0.53 eV GaInAsSb thermophotovoltaic diode
Renew Energy
(2015) - et al.
Design and analysis of solar thermophotovoltaic systems
Renew Energy
(2011) - et al.
Steady state analysis of a storage integrated solar thermophotovoltaic (SISTPV) system
Sol Energy
(2013)
Upper bounds for solar thermophotovoltaic efficiency
Renew Energy
New development of one-dimensional Si/SiO2 photonic crystals filter for thermophotovoltaic applications
Renew Energy
Solar thermophotovoltaic energy conversion systems with two-dimensional tantalum photonic crystal absorbers and emitters
Sol Energy Mater Sol C
Night time performance of a storage integrated solar thermophotovoltaic (SISTPV) system
Sol Energy
Parametric characteristics of a solar thermophotovoltaic system at the maximum efficiency
Energy Convers Manage
Detailed balance analysis of solar thermophotovoltaic systems made up of single junction photovoltaic cells and broadband thermal emitters
Sol Energy Mater Sol C
Performance analysis of solar thermophotovoltaic conversion enhanced by selective metamaterial absorbers and emitters
Int J Heat Mass Trans
Optimum semiconductor bandgaps in single junction and multi-junction thermophotovoltaic converters
Sol Energy Mater Sol C
Cited by (23)
Sustainable urban energy solutions: Forecasting energy production for hybrid solar-wind systems
2024, Energy Conversion and ManagementMulti-field coupling characteristics of the thermophotovoltaic cell under high-intensity laser beam radiation
2023, Infrared Physics and TechnologyEnergy and exergy analysis of an integrated photovoltaic module and two-stage thermoelectric generator system
2022, Applied Thermal EngineeringPerformance analyses on a concentrated photovoltaics driven direct contact membrane distillation coupled system
2022, DesalinationCitation Excerpt :Among the renewable energies, solar energy has drawn extensive attention because of widespread distribution and inexhaustible supply. To utilize solar energy stably and efficiently, researchers has proposed a variety of energy conversion devices, including photovoltaics (PVs), photovoltaic thermal collectors and solar heat pipes [3,4]. With the ability of directly converting solar energy into electricity, PVs have attracted considerable interest.
Optimal design and economic analysis of a hybrid process of municipal solid waste plasma gasification, thermophotovoltaic power generation and hydrogen/liquid fuel production
2022, Sustainable Energy Technologies and Assessments