This system consists of concentrating parabolic trough collector to magnify the solar radiation onto the focal point where absorber tube has been placed. Working fluid such as water is passed from the tube with the help of pump. In order to increase the overall efficiency of the system, photovoltaic cells are placed on the absorber tube so that hot water and electricity can be produced from one integrated system.

1. Solar Photovoltaic-Thermal (PV/t)
parabolic trough collector system
Project 1(BEB801)
Supervisor: Dr. Azharul Karim
MANAV R. SHAH
2 JUNE 2016

2. Aim of the project
To make a hybrid system by integrating Solar PV cells on the
absorber tube of the Solar thermal Parabolic Through collector
system to increase the overall efficiency.

3. Objectives of project1
 To integrate the cells on the absorber tube and design the layout to get
maximum power by altering voltage and current.
 Making the existing thermal system functional
 Try to convert maximum radiation into useful energy with minimum
thermal and electrical loss by altering the parameters.
 To obtain the value of efficiency of the thermal system (theoretically)

4. Why PV/t integration?
 Exposure to wider range of wavelengths
PV cell - 300nm to 1150nm
solar thermal collector- 200nm to 1000µm
 Reduces the cell temperature --- improves PV performance
 Increases the life of PV cells by reducing thermal stress
 Exhibits higher yield per square meter in highly populated areas
 Reduces balance of system costs
 Lower production costs, life-cycle costs, needs less maintenance

5. Theoretical thermal calculations

6. Forced Convection: It
occurs between water
and the inner surface of
the tube
Conduction: It occurs between the
inner surface and outer surface of
the metal
Radiation: It occurs from
radiation from the sun to the
outer surface of the pipe
Heat and mass transfer concepts on the
system

7. Parameter Value Parameter Value
Flow rate 3LPM = 0.05kg/s Rayleigh number 3.28*10−5
Effective surface
area of the
absorber tube
0.184m2 Nusselt number 10.7
Surface area of the
attached solar cell
0.1135m2 Heat transfer
coefficient
6.55W/m^2*K
Area of triangular
inlet and outlet
0.00117m2 Heat loss by
forced convection
66.3W
Bulk temperature 52.5°𝐶 Heat loss by
radiation
63.8W
Results from the theoretical calculations

8. Tin(0C) Heat flux from
pyrometer(W/m2)
Flow rate (LPM) Flow rate
(kg/sec)
Reynolds
number
Tout (oC)
19.1 (minimum) 794.78 (minimum) 3.33 (minimum) 0.055 1407 23.19
19.5 (average) 800 (average) 3 (average) 0.05 1279.5 23.95
19.71 (maximum) 811.5 (maximum) 3 (maximum) 0.05 1279.5 24.25
Temperature
difference
Percentage change
(%)
Energy gained ( 𝑸)
(kJ/s)
Available solar
irradiance(kJ/s)
Thermal efficiency
(theoretical) (%)
4.09 8.1 0.94 0.7486 79.6%
4.45 0.93 0.7536 81.03%
4.54 1.99 0.95 0.7644 82%
Results from the theoretical calculations

9. Recommendation
Attaching more RTDs at specific locations

10. PV integration

11. Why monocrystalline silicon?
 After the cell is used for a longer time, temperature in
the cell increases which leads to decrease in the cell
efficiency by 0.34 %/°𝐶 for monocrystalline silicon cells
and 0.45%/°𝐶 for polycrystalline.

12. Option1 Option2 Option3
Dimensions(mm*mm) 50*156 50*125 52*156
Quantity(pieces) 300 200 150
Efficiency 18% 18% 19%
Price US$300 US$400 AUD$367
Pros and cons The quantity was
more than the
required amount
and it was the 300
pieces is the
minimum quantity
to be ordered.
The cost of cutting is
very high. The
supplier charged
double the amount
for precutting the cell
to the required
dimensions.
The efficiency was
higher than others.
The quantity was of
desired amount. The
supplier added
auxiliary materials
such as tabbing wires
and busbars which
otherwise have to be
ordered separately.
Selection of cells based on received quotes

13. Size 52mm*156mm±0.5mm
Thickness 200mm±1mm
Front Anisotropically texturized surface and dark silicon nitride anti-
reflection coating
Back Full-surface aluminium back-surface field
Efficiency Eff (%) 18
Power Ppm(W) 1.148
Maximum Power current Ipm(A) 2.8
Short circuit Current Isc(A) 2.8-2.9
Maximum Power Voltage Vpm(V) 0.5
Open Circuit Voltage Voc(V) 0.6
Current Temperature Coefficient α 0.04%/0C
Voltage Temperature Coefficient β -0.32%/0C
Power Temperature Coefficient γ -0.42%/0C
Cell specifications

14. Characteristics
 High conversion efficiencies resulting in superior power output
performance
 Outstanding power output even in low light or high temperature
conditions
 Optimized design for ease of soldering and lamination
 Long-term stability, reliability and performance
 Low breakage rate

15. Orientation

16. Designing the layouts for the electrical system
to obtain maximum output power
Layouts

17. Case1: Using 14 pieces of 52mm*156mm cells on 2 faces
in series configuration

18. Case2: Using 14 pieces of 52mm*156mm cells on 2 faces
in parallel configuration

19. Case3: Using 28 pieces of 25mm*156mm cells on 2 faces
in series configuration

20. Case4: Using 28 pieces of 25mm*156mm cells on 2 faces in
parallel configurations

21. Current status

23. Recommendation
Using the most efficient cell (for research purpose only)
 Use the non-concentrating high efficiency cells recently developed by
UNSW researchers
 The triple-junction cell targets discrete bands of the incoming sunlight
and are capable of converting 35% of the sunlight into electricity

24. Thank you for your time and patience