DOI : 10.17577/IJERTV1IS10576
- Open Access
- Total Downloads : 675
- Authors : Vishant. M. Patel, H. A. Patel
- Paper ID : IJERTV1IS10576
- Volume & Issue : Volume 01, Issue 10 (December 2012)
- Published (First Online): 29-12-2012
- ISSN (Online) : 2278-0181
- Publisher Name : IJERT
- License:
This work is licensed under a Creative Commons Attribution 4.0 International License
Design And Development Of Solar PVT System
Vishant. M. Patel1*, H. A. Patel2*
1* M. Tech student, U. V. Patel College of Engineering, 2*Associate Professor, Mechanical Department, U.V.P.C.E. Kherva, Mehsana, Gujarat, India
Abstract
The energy obtains from the solar radiation by the photovoltaic system. A made a design and fabricated of a parallel flow solar water heater with tube type aluminum absorber plate. It has been develop the design and fabrication of water collector with photovoltaic cell. And employed to study the effects of the PV cell on its performance with collector for conduction and convection effect. The electricity conversion-efficiency of a solar cell for commercial application is about 615%. More than 85% of the incoming solar energy is either reflected or absorbed as heat energy. Consequently, the working temperature of the solar cells increases considerably after prolonged operations and the cell efficiency drops significantly. The hybrid photovoltaic collector technology using water as the coolant has been seen as a solution for improving the energy performance. Through good thermal-contact between the tube type aluminum absorber plate and the PV module, both the electrical efficiency can be raised. The study was carried out to evaluate the effect of liquid tube aluminum absorber plate is used in collector with PVcell. Commercial polycrystalline PV module of 0.113-m2 area is used for making a glazed PVT collector. An 18-W DC pump was used to circulate the water between the tank and the PV collector, Where the PVcell is mounting on the tube type absorber plate and cooled by inside water of collector and improve the performance of PVcell. Our observation is that very few studies and design appropriate recommendations are made which will aid PVT systems to improve their overall and electrical efficiency and reducing their cost, making combination of PVcell with collector.
-
Introduction
A photovoltaic thermal collector (or PVT collector) combines with the functions of a solar thermal collector and a PV module. It is converting the solar radiation to both electrical energy and heat energy. It is essentially a solar thermal module in which PV is integrated in the absorber. In this way, more solar energy is generated per unit surface area.
One example is a conventional flat plate solar heat collector with integrated PV cells on the absorber, to produce both thermal and electrical energy. For these systems, water is used as heat transfer fluid. The PV cells are pasted either directly on the absorber or interior on a cover plate with a dielectric material. This means that the only contact between the PV cells and the absorber or the cover plate is a high thermal contact. The heat transfer fluid runs inside the tube in the absorber and collects heat from the absorber. If the PV cells are pasted to the absorber, heat is also extracted from the PV cells resulting in a higher electrical efficiency of the PV cells. The heat transfer fluid can be circulated by a pump (a pumped system).
1.1Component of solar PVT system
– (1) Solar thermal collector
(2) Solar photovoltaic cell
-
Solar thermal collector: –
These collectors are better suited for moderate temperature applications where the demand temperature is 30-70 C and/or for applications that require heat during the winter months.
In Solar water heater water is heated by the use of solar energy. Solar heating systems are generally composed of solar thermal collectors, a fluid system to move the heat from the collector to its point of usage. The system may use electricity for pumping the fluid, and have a reservoir or tank for heat storage and subsequent use. The systems may be used to heat water for a wide variety of uses, including home, business and industrial uses. Heating swimming pools, under floor heating or energy input for space heating or cooling are more specific examples [2].
-
Solar photovoltaic cell: –
This element converts energy from sunlight directly into electricity. The more intensive is the
sunlight the more electricity the solar cell produces. This electricity is later used to run the pump without other sources of energy [2]
-
-
Radiation
-
Radiation terminology
-
Beam radiation:
Solar radiation that has not been absorbed or scattered and reaches the ground directly from the sun is called direct radiation or beam radiation.
program and then after radiation is calculated and generated the graph.
Ib, Id, Ig, IT Vs Time
1400
1200
1000
-
Diffuse radiation:
Diffuse radiation is that solar radiation received from the sun after its direction has been changed by reflection and scattering by atmosphere.
-
Global solar irradiance:
Solar radiation on a horizontal surface due to both direct sun rays and diffuse radiation.
Ib,
Id,
Ig,
800
600
400
200
Ib I
Idg
IT
-
Irradiance:
Amount of radiant energy incident on a surface per unit area per unit Time.
-
-
Calculate the radiation
The solar water heating collector is mainly dependant of solar intensity. The solar intensity is measure by solar intensity measuring instrument. The solar collector design is main depend of solar radiation. It has made a one solar water heater with PVT system. In this system first of one make master programe.This program is based on solar equation and angle. Its angle and equation is representing below:
-
Hourly global, beam and diffuse radiation
Based on an analysis of US data, ASHRAE has given a method for estimating the hourly Hourly global, beam and diffuse radiation (clear day) falling on a horizontal surface.
Hourly beam :
Ibn = A exp [-B / cos z ]
Hourly diffuse :
Id = C Ibn
Hourly global :
Ig = Ibn cos z + Id
This master program made in the matlab.it is representing of beam, diffuse, global radiation at any time. And the radiation is representing by radiation
08 9 10 11 12 13 14 15 16
Time
Figure 2.1 Radiation Vs Time
This master program made in the matlab.It is representing of beam, diffuse, global radiation at any time.
-
The total flux falling on a surface (IT):
The flux IT falling on a tilted surface at any instant is thus given by
IT = Ib rb + Id rd + (Ib + Ib) rr
-
Incident flux absorbed by absorber plate
The amount of incident flux absorbed by the absorbed by the absorber plate is given by
S = Ibrb () b+ Idrd () d +(Ib+Id) rr ()d
In this chapter we make one master program in the matlab.It is representing of beam, diffuse, global radiation at any time and any location. And we find the value of radiation.
-
-
-
Thermal design of solar PVT system
-
Area of collector
q = Ut AP (T1-Ta) AP =
Where,
Ut = top los coefficient AP = area of collector
q = solar flux absorbed by Absorber plate = S
-
collator heat removal factor and overall loss co-efficient
An iterative procedure will be required since both FR and Ul cannot be directly determined and the value of one is dependent on other.
Tp Vs area of collector
370
360
350
340
Tp
330
320
310
300
290
1 1.5 2 2.5 3 3.5
Area
Figure 3.1 Tp Vs Area of collector
This graph is represent to change of value of collector aea and observed value of plate temperature. It can observed by this graph increase the value of area of absorber plate with compare the value of absorber plate temperature is decreased because area of absorber plate is increase so that collector area is increase and heat losses is increase and temperature of plate is decreased.
Side loss coefficient:-
US =
Where,
L1 = length of collector (m) L2 = width of collector (m) L3 = thickness of collector (m)
Assume Ul = 4.0 W/m2
This is a reasonable assumption for collector with single glass cover and a non-selective absorber surface.
m1 = ( ) ½
x =
Effectiveness Ø =
Collector effiency factor (F')
F' =
Collector heat-removal factor (FR) =
FR = )]
FR = 0.83
The useful heat gain rate for the collector (qu):
q u = FR Ap [ s – (Tfi Ta) ] q u = 670 W
q l = S Ap qu q l = 303 W
Overall loss co-efficient (ql):-
q l = Ul Ap ( Tpm Ta) Tpm = 342 °
-
Water outlet temperature (T )
US = 0.04 W/m2-K L3 = 0.03 m
Thickness of collector = 0.010 m
Bottom loss efficient:-
Ub =
Ub = 0.08 W/m2-K
Total loss:-
Ul = Ut + Ub + Us Ul = 4.53 W/m2-K
fo
The water outlet temperature is obtained from the heat balance equation. Substituting
qu = m × Cp ( Tfo Tfi ) Tfo = 339
This graph is represent to change of value of Mass flow rate and observed value of outlet temperature of water. It can observed by this graph increase the value of Mass flow rate with value of outlet temperature of water is decreased.
370
368
366
364
T fo
362
360
358
356
Tfo Vs mass flow rate
Area of PVcell A1 =0.113 Thickness of cell LC = 0.001mm Temperature of PVcell =
Tc3 = Tc3 = 337°
-
-
Experimental set up
A schematic view of the constructed single flow with single glass cover water heater with PVcell is shown in figure 4.1. In this study the PVcell is mounted on two different location of absorber plates
were used. The liquid tube type absorber plates were
20 30 40 50 60 70 80 90 100
m
Figure 3.2 Outlet temperature of Vs Mass flow rate
-
Instantaneous efficiency
Instantaneous efficiency based on the absorber plate area is given by
i =
i = 0.4811
Vs T
made of aluminum material with black coating. Dimension and plate thickness for absorber plate were 1090 mm x 460 mm and 1.3 mm and glass cover is 5 mm thickness was used as glazing.
Single pass glass cover was used in collector. Thermal losses through the collector backs are mainly due to the conduction across the insulation (thickness of bottom side insulation 6 cm and side insulation thickness 1.5 cm). The absorber plate surface which is the most important part of the solar water heater consist of a circular cross sectional liquid tube made of aluminum material. The distance between glass cover and absorber plate is 3 cm and thickness of collector is 10 cm. types-I the PVcell is mounted on absorber plate.
0.7
0.65
0.6
0.55
i 0.5
0.45
0.4
0.35
i fi
And type-II the PVcell is mounted 25 mm above absorber plate.
300 310 320 330 340 350 360
Tfi
Figure 3.3 Efficiency Vs Inlet temperature of water
This graph is represent to change of value of water input temperature and observed value of efficiency. We observed by this graph when the value of inlet temperature of water is increase then efficiency is decrease.
-
Temperature of PVcell
For convection and conduction effect:
Thermal conductivity of cell kc =145
Figure 4.1 Solar PVT system set-up
The water tank is providing for collect the heated water. The capacity of tank is 20 liter with protecting insulation.
Four valves are providing for circulation of water in collector. There two valves are water inlet and outlet valve and other two valves are providing on
liquid tube its measure the mass flow rate and maintain overflow water. All valves are made in brass material.
Two plastic pipes are used circulating the water between water tank and collector and collector to water tank by using pump and Its pipe is join with tube are clamping.
The 18 watt D.C pump is used in the collector. The collector water is circulated by pump. In this system to measure the temperature by using 10 switches 4-pole thermocouple with different temperature of collector. The angle protector is providing in PVT collector construction and to set the angle by using angle protector. It is made in M.S. bar. Solar radiation is measure by pyrenometer and velocity of air is measure by anemometer.
-
-
Results and discussions
Collector performance tests were conducted on days with clear sky condition. The collector slope was adjusted to 38 , which is considered suitable for the geographical location of Mehsana (23.40 N, 72.60 E). The collector efficiency improvements for single- pass type solar water heater with PVT system were calculated using Eq.
The thermal efficiency and electrical efficiency of a PVT collector are, respectively, given by:
t =
3
11:30
616
39.7
41.3
15.7
0.4
6.3
0.4343
4
12:00
639
39.5
41.2
15.7
0.39
6.1
0.4448
5
12:30
676
39.9
41.7
15.2
0.4
6.1
0.4452
6
1:00
689
39.9
41.8
15.1
0.4
6.0
0.4611
7
1:30
690
40.3
42.2
15.3
0.39
6.0
0.4604
8
2:00
689
40.9
42.8
15.2
0.39
5.9
0.4611
Table 5.2 Experimental reading for m = 0.02 kg/s with convection effect
No
Time
I
(w/m2)
Tin (ºc )
Tout (ºc )
V
(volt)
I
(amp)
P
(kw)
Th (%)
1
10:30
574
34.5
36
14.9
0.4
6.0
0.4369
2
11:00
591
34.9
36.5
14.9
0.4
6.0
0.4527
3
11:30
616
34.7
36.4
14.8
0.4
5.9
0.4614
4
12:00
647
35.5
37.3
14.7
0.4
5.9
0.4652
5
12:30
676
35.9
37.8
14.5
0.4
5.8
0.4699
6
1:00
689
36.9
38.9
14.4
0.4
5.8
0.4853
7
1:30
688
37.3
39.3
14.2
0.4
5.7
0.486
8
2:00
688
38.9
40.9
14.1
0.4
5.6
0.486
conduction
convection
Efficency Vs Time
0.5
0.48
0.46
0.44
0.42
0.4
0.38
0.36
10:30 11:00 11:30 12:00 12:30 13:30 14:30 15:30
Time
Effiency
e =
Where m and C are, respectively, the mass flow rate and specific heat capacity of the coolant, AP the collector aperture area, Tin and Tout the coolant temperatures at the inlet and outlet, Ig the incident solar irradiance normal to surface.
-
Performance on PV cell with conduction effect and convection effect
Experimental studies had been performed during the on day (15.10.2012) period. And constant water mass flow rates 0.02 kg/s is also investigated at the experiments.
No
Time
I
(w/m2)
Tin (ºc )
To (ºc )
V
(volt)
I
(amp)
P
(kw)
Th (%)
1
10:30
566
38.5
39.9
16
0.4
6.4
0.4136
2
11:00
581
38.9
40.4
15.9
0.4
6.4
0.4317
Table 5.1 Experimental reading for m = 0.02 kg/s with conduction effect
Figure 5.1 Efficiency Vs time
conduction
convection
Power
It is representing that the thermal efficiency of convection effect is high comparing to conduction effect. The effect of conduction is 41.36% to 46.11% and the effect of convection is 43.69% to 48.60% respectively.
Power Vs Time
6.6
6.4
6.2
6
5.8
5.6
5.4
5.2
10:30 11:00 11:30 12:00 12:30 13:30 14:30 15:30
Time
Figure 5.2 Power Vs Time
power
This graph is representing the effect of PV cell on collector with power Vs time. It is representing that the power of convection effect is low comparing to conduction effect. The effect of conduction is 6.4W to 5.9W and the effect of convection is 6.0W to 5.6W respectively.
-
Performance on PV cell constant mass flow rate with variation of inlet temperature.
Experimental studies had been performed during the on day (11.10.2012) period. And constant water mass flow rates 0.01 kg/s is also investigated at the experiments.
No
Time
I
(W/m2)
Tin (ºc )
Tout (ºc )
V
(Volt)
I
(Amp)
P
(w)
Th (%)
1
10:30
650
38.5
41.9
14.2
0.4
5.68
0.4373
2
11:00
656
39.9
43.3
14.1
0.4
5.64
0.4333
3
11:30
646
41.7
45.0
13.8
0.4
5.52
0.4271
4
12:00
653
43.5
46.7
13.7
0.4
5.48
0.4097
5
12:30
666
45.9
49.1
13.6
0.4
5.44
0.4017
6
1:00
689
47.9
51.2
13.4
0.4
5.36
0.4004
7
1:30
696
49.3
52.6
13.4
0.4
5.36
0.3964
8
2:00
733
51.9
55.3
13.2
0.4
5.28
0.3878
Table 5.3 Constant mass flow rate with variation of inlet temperature
power Vs Inlet temperature
5.8
5.7
5.6
5.5
5.4
5.3
5.2
5.1
5
41.9 43.3 45 46.7 49.1 51.2 52.6 55.3
Inlet temp
Figure 5.4 power Vs Inlet Temperatures
This graph is representing of performance of collector with PVcell with constant mass flow rate and variation of inlet temperature. When inlet temperature is increase by 38.5º to 51.9º so that power output is decrease by 5.68 kW to 5.28 kW because temperature difference is reduce.
-
Performance on PVcell inlet temp Constant with variation of mass flow rate
Effiency
Experimental studies had been performed during the on day (12.10.2012) period. And variation of mass flow rates 0.01 kg/s, 0.02 kg/s, 0.03 kg/s are also investigated at the experiments.
Effiency Vs Inlet temperature
0.45
0.44
0.43
0.42
0.41
0.4
0.39
0.38
0.37
0.36
38.5 39.9 41.7 43.5 45.9 47.9 49.3 51.9
Inlettemperature
Figure 5.3 Efficiency Vs inlet temperature
This graph is representing of performance of
0.5
0.45
0.4
0.35
Effiency
0.3
0.25
0.2
0.15
0.1
0.05
0
Effiency Vs Time
m = 0.01 kg/s
m = 0.02 kg/s
m = 0.03 kg/s
10:30 11:00 11:30 12:00 12:30 13:30 14:30 15:30
Time
Figure 5.5 Efficiency Vs time
This graph is representing the performance of
collector with PVcell with constant mass flow rate and variation of inlet temperature. When inlet temperature is increase by 38.5º to 51.9º so that efficiency is decrease 43.73% to 38.78% respectively.
PV cell with variation of different three mass flow rates of 0.01 kg/s, 0.02kg/s, 0.03 kg/s and inlet temperature is constant. When mass flow rate is 0.01kg/s so that the efficiency is increase 36.15 % to 41.69%,mass flow rate is 0.02 kg/s so that the efficiency is increase 38.07% to 42.63%,mass flow rate is 0.03 kg/s so that efficiency is increase 41.04% to 46.38%.
Power Vs Time
8
7
6
5
4
3
2
1
0
m = 0.01 kg/s
m = 0.02 kg/s m = 0.03 kg/s
10:30 11:00 11:30 12:00 12:30 13:30 14:30 15:30
Time
Power
Figure 5.6 Power Vs Time
This graph is representing the performance of PV cell with variation of different three mass flow rates of 0.01 kg/s, 0.02kg/s, 0.03 kg/s and inlet temperature is constant. When mass flow rate is 0.01kg/s so that the power output is decrease 5.76W 5.40W, mass flow rate is 0.02 kg/s so that the power output is decrease 6.20w to 5.72w mass flow rate is
0.03 kg/s so that efficiency is decrease 6.76w to 6.00w.
-
Performance on PV cell with different temperature effect
Experimental studies had been performed during the on day (15.10.2012) period. And constant water mass flow rates 0.02 kg/s is also investigated at the experiments.
Temperature Vs Time
60
Tp
Tc
Ttu
Tg
Temperature
50
40
30
20
10
0
10:30 11:00 11:30 12:00 12:30 13:30 14:30 15:30
Time
Figure 5.7 Temperature Vs time
This graph is representing to temperature Vs time effect. It is represent that the temperature of plat is high compare to temperature of cell, tube, glass cover and the temperature of glass cover is low compare to other temperature.
-
-
Conclusion
From above experiments following results have obtained.
-
In this dissertation work, we check the performance of PVT system with various
mass flow rate based on the result obtained, it can be concluded the thermal efficiency of convection effect is high comparing to conduction effect and the power of convection effect is low comparing to conduction effect for PVT system.
-
When inlet temperature is increase then efficiency and power output is decrease for PVT system with constant mass flow rate and variation of inlet temperature.
-
When mass flow rate is increase then efficiency and power output is increase with respect to time for PVT system.
-
The temperature of plate is high compare to temperature of cell, tube, glass cover and the temperature of glass cover is low compare to other temperature for PVT collector.
-
-
References
-
Wei He, Tin-Tai Chow , Jie Ji, Jianping Lu, Gang Pei, Lok-shun Chan, Hybrid hotovoltaic and thermal solar-collector designed for natural circulation of water, Applied Energy 83 (2006) 199210.
-
Chii-Dong Ho , Ho-Ming Yeh, Tsung-Ching Chen, Collector efficiency of upward-type double-pass solar air heaters with fins attached, International Communications in Heat and Mass Transfer 38 (2011) 4956.
-
Wei He, Tin-Tai Chow , Jie Ji, Jianping Lu, Gang Pei, Lok-shun Chan, Hybrid photovoltaic and thermal solar-collector designed for natural circulation of water, Applied Energy 83 (2006) 199210.
-
G.N. Tiwari, R.K. Mishra , S.C. Solanki, Photovoltaic modules and their applications: A review on thermal modelling , Applied Energy 88 (2011) 22872304.
-
Gajendra Singh , Shiv Kumar , G.N. Tiwari , Design, fabrication and performance evaluation of a hybrid photovoltaic thermal (PVT) double slope active solar still , Desalination 277 (2011) 399406.