# Performance Evaluation of Photovoltaic/Thermal (PV/T) System Using Different Design Configurations

^{1}

^{2}

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Research Methods

#### 2.1. Mathematical Model

- (1)
- There is no change in the physical dimensions and material properties of the collector components.
- (2)
- For the parallel tube heat exchanger, temperature and flow rate in all tubes were taken as same.
- (3)
- The ohmic losses in the PV cells and edge losses are neglected.
- (4)
- All heat transfer coefficients were calculated in real-time [19].
- (5)
- Only the absorption loss of glass is taken into consideration.
- (6)
- For the glass-to-glass case, the glass cover2 serves as a sheet for the copper tube (carrying water), while for the glass-to-PV backsheet case, the PV backsheet works as a sheet for the copper tube considering famous sheet and tube configuration.

#### 2.2. Exergy Analysis

#### 2.3. Description of Proposed PV/T Systems

#### 2.4. Model Validation

## 3. Results and Discussion

## 4. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## Nomenclature

$A$ | surface area (m^{2}) |

$C$ | specific heat (J/kg °C) |

$E$ | electrical power (W) |

$\mathrm{E}\mathrm{x}$ | exergy rate |

$\mathrm{E}{\mathrm{x}}_{\mathrm{o}}$ | overall exergy gain |

$G$ | solar radiation (W/m^{2}) |

$h$ | heat transfer coefficient (W/m^{2} °C) |

${h}_{wind}$ | wind velocity (W/m^{2} °C) |

$\mathrm{k}$ | thermal conductivity (W/m °C) |

$M$ | mass (kg) |

$\mathsf{\u1e41}$ | mass flow rate (kg/s) |

$PF$ | packing factor |

$Q$ | energy (W) |

${Q}_{u}$ | useful energy gain (W) |

$T$ | temperature (°C) |

${D}_{i}$&${D}_{o}$ | tube inner & outer diameters |

$Nu$ | Nusselt number |

$Re$ | Reynolds number |

$Pr$ | Prandtl number |

Greek | |

$\alpha $ | absorptivity |

$\mathsf{\tau}$ | transmissivity |

$\mathsf{\delta}$ | thickness (m) |

$\mathsf{\sigma}$ | stefan-boltzmann constant (W·m^{−2}·K^{−4}) |

$\mathsf{\u014b}$ | efficiency |

$\mathsf{\epsilon}$ | emissivity |

${\mathsf{\u014b}}_{PVT}$ | primary energy saving efficiency |

Subscripts | |

$a$ | circulating air |

$b$ | back panel |

$bo$ | bond or adhesive |

$c$ | collector |

$e$ | electrical |

$f$ | circulating water |

$g1$ | glass cover1 |

$g2$ | glass cover2 |

$o$ & $in$ | outlet & inlet |

$p$ | PV backsheet or PVF film-based backsheet |

$pp$ | power plant |

$s$ | solar cells |

$t$ | tube |

$th$ | thermal |

$\infty $ | ambient air |

## References

- Jewell, J.; McCollum, D.; Emmerling, J.; Bertram, C.; Gernaat, D.E.; Krey, V.; Paroussos, L.; Berger, L.; Fragkiadakis, K.; Keppo, I. Limited emission reductions from fuel subsidy removal except in energy-exporting regions. Nature
**2018**, 554, 229. [Google Scholar] [CrossRef] [PubMed][Green Version] - Perea-Moreno, M.-A.; Hernandez-Escobedo, Q.; Perea-Moreno, A.-J. Renewable Energy in Urban Areas: Worldwide Research Trends. Energies
**2018**, 11, 577. [Google Scholar] [CrossRef][Green Version] - Chow, T.T. A review on photovoltaic/thermal hybrid solar technology. Appl. Energy
**2010**, 87, 365–379. [Google Scholar] [CrossRef] - Charalambous, P.; Maidment, G.; Kalogirou, S.; Yiakoumetti, K. Photovoltaic thermal (PV/T) collectors: A review. Appl. Therm. Eng.
**2007**, 27, 275–286. [Google Scholar] [CrossRef][Green Version] - Taylor, R.A.; Phelan, P.E.; Otanicar, T.P.; Adrian, R.; Prasher, R. Nanofluid optical property characterization: Towards efficient direct absorption solar collectors. Nanoscale Res. Lett.
**2011**, 6, 1–11. [Google Scholar] [CrossRef][Green Version] - Hussain, M.I.; Ménézo, C.; Kim, J.-T. Advances in solar thermal harvesting technology based on surface solar absorption collectors: A review. Sol. Energy Mater. Sol. Cells
**2018**, 187, 123–139. [Google Scholar] [CrossRef] - Bhattarai, S.; Oh, J.-H.; Euh, S.-H.; Krishna Kafle, G.; Hyun Kim, D. Simulation and model validation of sheet and tube type photovoltaic thermal solar system and conventional solar collecting system in transient states. Sol. Energy Mater. Sol. Cells
**2012**, 103, 184–193. [Google Scholar] [CrossRef] - Rommel, M.; Zenhäusern, D.; Baggenstos, A.; Türk, O.; Brunold, S. Development of glazed and unglazed PVT collectors and first results of their application in different projects. Energy Procedia
**2015**, 70, 318–323. [Google Scholar] [CrossRef][Green Version] - Vats, K.; Tomar, V.; Tiwari, G.N. Effect of packing factor on the performance of a building integrated semitransparent photovoltaic thermal (BISPVT) system with air duct. Energy Build.
**2012**, 53, 159–165. [Google Scholar] [CrossRef] - Hosseinzadeh, M.; Sardarabadi, M.; Passandideh-Fard, M. Energy and Exergy Analysis of Nanofluid Based Photovoltaic Thermal System Integrated with Phase Change Material. Energy
**2018**, 147, 636–647. [Google Scholar] [CrossRef] - Shahsavar, A.; Ameri, M.; Gholampour, M. Energy and exergy analysis of a photovoltaic-thermal collector with natural air flow. J. Sol. Energy Eng.
**2012**, 134, 011014. [Google Scholar] [CrossRef] - Saidur, R.; BoroumandJazi, G.; Mekhlif, S.; Jameel, M. Exergy analysis of solar energy applications. Renew. Sustain. Energy Rev.
**2012**, 16, 350–356. [Google Scholar] [CrossRef] - Pathak, M.J.M.; Sanders, P.G.; Pearce, J.M. Optimizing limited solar roof access by exergy analysis of solar thermal, photovoltaic, and hybrid photovoltaic thermal systems. Appl. Energy
**2014**, 120, 115–124. [Google Scholar] [CrossRef][Green Version] - Tripanagnostopoulos, Y. Aspects and improvements of hybrid photovoltaic/thermal solar energy systems. Sol. Energy
**2007**, 81, 1117–1131. [Google Scholar] [CrossRef] - Abu Bakar, M.N.; Othman, M.; Hj Din, M.; Manaf, N.A.; Jarimi, H. Design concept and mathematical model of a bi-fluid photovoltaic/thermal (PV/T) solar collector. Renew. Energy
**2014**, 67, 153–164. [Google Scholar] [CrossRef] - Jarimi, H.; Bakar, M.N.A.; Othman, M.; Din, M.H. Bi-fluid photovoltaic/thermal (PV/T) solar collector: Experimental validation of a 2-D theoretical model. Renew. Energy
**2016**, 85, 1052–1067. [Google Scholar] [CrossRef] - Baljit, S.S.S.; Chan, H.Y.; Audwinto, V.A.; Hamid, S.A.; Fudholi, A.; Zaidi, S.H.; Othman, M.Y.; Sopian, K. Mathematical modelling of a dual-fluid concentrating photovoltaic-thermal (PV-T) solar collector. Renew. Energy
**2017**, 114, 1258–1271. [Google Scholar] [CrossRef] - Chow, T. Performance analysis of photovoltaic-thermal collector by explicit dynamic model. Sol. Energy
**2003**, 75, 143–152. [Google Scholar] [CrossRef] - Hussain, M.I.; Lee, G.H. Thermal performance comparison of line-and point-focus solar concentrating systems: Experimental and numerical analyses. Sol. Energy
**2016**, 133, 44–54. [Google Scholar] [CrossRef] - Hussain, M.I.; Lee, G.H. Numerical and experimental heat transfer analyses of a novel concentric tube absorber under non-uniform solar flux condition. Renew. Energy
**2017**, 103, 49–57. [Google Scholar] [CrossRef] - Garg, H.P.; Adhikari, R.S. Transient simulation of conventional hybrid photovoltaic/thermal (PV/T) air heating collectors. Int. J. Energy Res.
**1998**, 22, 547–562. [Google Scholar] [CrossRef] - Holman, J.P. Heat Transfer; Metric, S.I., Ed.; McGraw-Hill: New York, NY, USA, 1989. [Google Scholar]
- Agrawal, S.; Tiwari, G. Energy and exergy analysis of hybrid micro-channel photovoltaic thermal module. Sol. Energy
**2011**, 85, 356–370. [Google Scholar] [CrossRef] - Singh, S.; Agrawal, S.; Avasthi, D. Design, modeling and performance analysis of dual channel semitransparent photovoltaic thermal hybrid module in the cold environment. Energy Convers. Manag.
**2016**, 114, 241–250. [Google Scholar] [CrossRef] - Joshi, A.S.; Tiwari, A.; Tiwari, G.N.; Dincer, I.; Reddy, B.V. Performance evaluation of a hybrid photovoltaic thermal (PV/T)(glass-to-glass) system. Int. J. Therm. Sci.
**2009**, 48, 154–164. [Google Scholar] [CrossRef]

**Figure 1.**Schematic of dual-fluid photovoltaic/thermal (PV/T) system with glass-to-glass and glass-to-PV backsheet cases.

**Figure 4.**Different layers temperatures across (

**a**) glass-to-glass PV/T system (

**b**) glass-to-PV backsheet based PV/T system.

**Figure 9.**Yearly variations of electrical efficiency of PV/T system with glass-to-glass and glass-to-PV backsheet cases.

**Figure 10.**Yearly variations of total thermal efficiency of PV/T system with glass-to-glass and glass-to-PV backsheet cases.

**Figure 11.**Yearly variations of Overall exergy efficiency of PV/T system with glass-to-glass and glass-to-PV backsheet cases.

PV cells [17] | Length & width | 1.62 m & 0.98 m |

Absorptivity | 0.9 | |

Emissivity | 0.88 | |

Specific heat | 900 J/(kg K) | |

Temperature coefficient | 0.0045/°C | |

Reference PV panel temperature | 298.15 K | |

Thickness of EVA+PV cells | 1.2 mm | |

Thermal conductivity | 148 W/(m K) | |

Glass cover | Glass solar transmittance | 92% |

Thickness of tempered glass | 3 mm | |

Specific heat | 670 (J/kg) | |

Density | 2200 (kg/m^{3}) | |

Extinction coefficient | 26 (/m) | |

PV backsheet | Thickness of PV backsheet | 0.5 mm |

Thermal conductivity | 0.2 W/(m K) | |

Absorptivity of PV backsheet | 0.5 | |

Copper tube | Inner diameter | 0.008 m |

Thickness | 0.0012 m | |

Specific heat | 903 J/(kg K) | |

Density | 2702 kg/m^{3} | |

No. of tubes | 9 | |

Tube spacing | 0.11 m | |

Material | Copper | |

Back panel | Density | 1520 kg/m^{3} |

Specific heat | 840 J/(kg K) | |

Thermal conductivity | 0.134 W/(m K) | |

Thickness of back panel | 4 mm | |

Fluids used | Water & air | - |

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. |

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

## Share and Cite

**MDPI and ACS Style**

Hussain, M.I.; Kim, J.-T.
Performance Evaluation of Photovoltaic/Thermal (PV/T) System Using Different Design Configurations. *Sustainability* **2020**, *12*, 9520.
https://doi.org/10.3390/su12229520

**AMA Style**

Hussain MI, Kim J-T.
Performance Evaluation of Photovoltaic/Thermal (PV/T) System Using Different Design Configurations. *Sustainability*. 2020; 12(22):9520.
https://doi.org/10.3390/su12229520

**Chicago/Turabian Style**

Hussain, M. Imtiaz, and Jun-Tae Kim.
2020. "Performance Evaluation of Photovoltaic/Thermal (PV/T) System Using Different Design Configurations" *Sustainability* 12, no. 22: 9520.
https://doi.org/10.3390/su12229520