Energy analysis of a novel butterfly serpentine flow-based PV/T and PV/T heat pump system with phase change material – an experimental comparative study

ABSTRACT

Solar photovoltaic (PV) technologies have the advantage of making electricity from solar energy. However, it also has the disadvantage of low energy exchange efficiency, which is worse when PV modules overheat. To address the issues, a novel butterfly serpentine flow pattern was developed and analyzed for a PV thermal collector (PV/T) system and a PV/T heat pump (PV/T-HP) system with and without Hydrated Salt (HS) Phase Change Material (PCM). In this work, energy assessments were performed on a PV/T water (PV/T-W), a PV/T water PCM system (PV/T-W-PCM), PV/T-HP, and a PV/T-HP-PCM system. The energy performance of all four cases was investigated and compared with the base uncooled PV system. PV/T-W, PV/T-W-PCM, PV/T-HP, and PV/T-HP-PCM had higher average electrical efficiency compared to a base PV system by 6.21%, 13.44%, 20.57%, and 26.07%, respectively. The maximum thermal efficiency of PV/T-W and PV/T-W-PCM system were 76.25% and 89.82%, respectively. Similarly, the coefficient of performance (COP) of PV/T-HP and PV/T-HP-PCM systems were 3.88 and 4.68, respectively.

GRAPHICAL ABSTRACT

KEYWORDS:

• Heat pump
• PV/T
• PCM
• COP
• energy

Nomenclature

Abbreviations	=	Description
PV	=	Photovoltaic System
HP	=	Heat Pump
PCM	=	Phase Change Material
PV/T-W	=	Photovoltaic Thermal Collector (water system)
PV/T-W- PCM	=	Photovoltaic Thermal collector with Phase Change Material system (Water +PCM)
PV/T-HP	=	Photovoltaic Thermal Collector with Heat Pump system
PV/T-HP- PCM	=	Photovoltaic Thermal collector with Phase Change Material and Heat Pump system
HS	=	Hydrated Salt
LH	=	Latent Heat
COP	=	Coefficient of Performance
Symbols	=	Description
β	=	Slope of the system (°)
$\mathit{\eta }$	=	Efficiency (%)
P	=	Electrical power (W)
$\mathrm{\Delta P}$	=	Change in Power (W)
$\mathrm{\Delta T}$	=	Change in temperature (°)
G	=	Solar Irradiation (W/m2)
A	=	Area of PV (m2)
Q	=	Heat (kJ)
p	=	Pressure
Nc	=	No of collector
T	=	Temperature (°C)
m	=	Mass (kg)
Ay	=	Accuracy
w	=	Uncertainties
X	=	Independent Variables
$w_R$	=	Uncertainty in Result
a	=	ambient
$\mathrm{c}$	=	cell
$\mathit{S}$	=	Sun
max	=	Maximum
min	=	Minimum
El	=	Electrical
com	=	Compressor
con	=	Condenser
eva	=	Evaporator
u	=	Useful
$\mathit{r}/\mathit{R}$	=	Refrigerant
w	=	Water
m	=	Mass
h	=	Enthalpy
S	=	Entropy
in	=	Inlet

Acknowledgements

The authors gratefully acknowledge the management of Bannari Amman Institute of Technology (India) for providing facilities to conduct this research work.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Prakash K B

Mr. Prakash K B is doing doctorate from Bannari Amman Institute of Technology, Sathyamangalam as a part time scholar. He acquired a B.E. in Mechanical Engineering from the PSG College of Technology, Coimbatore and an M.E. in Thermal Engineering from the Government College of Technology, Coimbatore. His primary research interest are Solar Energy, PV/T system, Heat Pump system, Phase change Materials, refrigeration and air conditioning system. His research contributions include 20 publications in international journals besides several publications in conference proceedings. He is currently associated with Bannari Amman Institute of Technology, Sathyamangalam as Assistant Professor of Mechanical Engineering.

Amarkarthik A

Dr. Amarkarthik A has completed his doctorate degree from Bannari Amman Institute of Technology, Sathyamangalam. He holds bachelor degree in Mechanical Engineering and Master Degree in Engineering Design and has been in teaching and research for more than 17 years. His primary research interest is performance enhancement of ocean wave energy conversion technologies. His research contributions include 25 publications in international journals. He is currently associated with Bannari Amman Institute of Technology, Sathyamangalam as Professor of Mechanical Engineering.