ABSTRACT
Photovoltaics (PV) is an ever-evolving field. Significant technological advancement in the PV field has been evident in recent years, including PV concentrators to enhance energy density. The present experimental study explores the viability of using a refractive Fresnel lens for electrical and thermal energy through a novel approach, i.e. irradiance bi-focussing method. Unlike in most of the concentrated PV (CPV) studies, real size PV module (polycrystalline) is used here, and its surface temperature was maintained well within 80°C with the help of a self-sustainable (burlap-based) passive cooling technique. Since the concentrated irradiance gets bifurcated and simultaneously received by both PV module (≈⅓) and the thermal collector (≈⅔), the power output from CPV is more than double compared to the reference module, and the maximum thermal efficiency recorded is 48%. Even the exergy analysis upheld the proposed system as the maximum exergy efficiency is ≈ 2.5 times compared to the reference module. Concerning the heat gain, the thermal collector performance is on par with a conventional solar water heater. Hence, such a combi system can entertain a variety of day-to-day energy applications. Further, as the distance between the concentrator and PV module changes the illumination level, it can be optimized based on the cooling and/or PV module type.
Highlights
Demonstration of bi-focus of Fresnel lens for concentrated solar PV/thermal system
Burlap-based passive cooling technique for concentrated photovoltaics
Power output enhanced by 2.5 times and thermal output comparable to solar water heater
Combi system proposed for a variety of day-to-day energy applications
Nomenclature
A | = | Module area (m2) |
= | Specific heat (kJ/kgK) | |
Ex | = | Exergy |
I | = | Current (A), Irradiance (W/m2) |
L | = | Length (m) |
= | Mass flow rate (kg/s) | |
P | = | Power (W) |
Q | = | Heat gain (W) |
T | = | Temperature (K) |
Ul | = | Overall coefficient (W/m2K) |
V | = | Voltage (V) |
Greek symbols | = | |
η | = | Efficiency |
= | Temperature difference | |
= | Transmissivity | |
Subscripts | = | |
a | = | ambient |
e | = | energy |
el | = | electrical |
ex | = | exergy |
f | = | fresnel lens |
in | = | input |
m | = | module |
m, max | = | maximum |
max-th | = | maximum theoretical |
oc | = | open-circuit |
out | = | output |
s | = | system, sun |
sc | = | short-circuit |
tc | = | thermal collector |
th | = | thermal |
Acronyms | = | |
CPV | = | Concentrating photovoltaic |
CPVT | = | Concentrating photovoltaic thermal |
FF | = | Fill factor |
MJSC | = | Multijunction solar cells |
PMMA | = | Poly methyl methacrylate |
PV | = | Photovoltaic |
RPV | = | Reference photovoltaic |
Disclosure statement
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:
Avaliability of data and materials
The data that support the findings of this study are available from the corresponding author upon reasonable request.
Ethical Approval
This article does not contain any studies with human participants or animals performed by any of the authors.
Consent to participate
All the authors give their consent to having participated in the current work..
Consent to publish
All the authors give their consent for publication of this work.
Additional information
Funding
Notes on contributors
N. Vignesh
Mr. N. Vignesh has completed his undergraduate degree, i.e. Bachelor of Technology in Mechanical and Industrial Engineeering, from Manipal Institute of Technology, Manipal, India during July 2022. He is currently working as Maintenance engineer in Reliance Industries Limited, Surat, India. His research interests are thermal management of photovoltaic modules and concentrated solar thermal systems.
U C Arunachala
Dr. U C Arunachala is a Professor in the Department of Mechanical and Industrial Engineering at Manipal Institute of Technology, Manipal, India. He has more than 20 years of research and teaching experience. His research interests include analysis of solar thermal systems, thermal management of photovoltaic modules, stability analysis of natural circulation loops, thermosyphon heat transport systems, heat transfer augmentation of thermal systems and heat exchanger analysis.
K. Varun
Mr. K. Varun is a PhD Research Scholar in the Department of Mechanical and Industrial Engineering at Manipal Institute of Technology, Manipal, India. He is currently working on developing an indoor solar cooking system using thermosyphon heat transport devices. His research interests are heat transfer augmentation techniques, thermal management of photovoltaic modules, solar thermal systems, natural circulation loops, and thermosyphon heat transport systems.