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International Journal of Emerging Trends & Technology in Computer Science (IJETTCS) is an online Journal in English published bimonthly for scientists, Engineers and Research Scholars involved in computer science, Information Technology and its applications to publish high quality and refereed papers. Papers reporting original research and innovative applications from all parts of the world are welcome. Papers for publication in the IJETTCS are selected through rigid peer review to ensure originality, timeliness, relevance and readability. The aim of IJETTCS is to publish peer reviewed research and review articles in rapidly developing field of computer science engineering and technology. This journal is an online journal having full access to the research and review paper. The journal also seeks clearly written survey and review articles from experts in the field, to promote intuitive understanding of the state-of-the-art and application trends. The journal aims to cover the latest outstanding developments in the field of Computer Science and engineering Technology.
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International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012 ISSN 2278-6856
Technical Feasibility of Photovoltaic Fuel
Cell: A Model of Green Home Power
Supply for Rural India
S.N.Singh1, Preeta John2, Navneet Prabhakar3
1
National Institute of Technology Jamshedpur, India
2
NTTF Jamshedpur, India
3
National Institute of Technology Jamshedpur, India
results in almost no CO2 emission, which will help in
Abstract: In this paper a hybrid solar PV fuel cell (PVFC) reducing the rate of global warming [2]. In order to
power generating system employing PV module, Battery for adopt such system for rural environment, the technical
storage , PEM electrolyser for hydrogen generation, PEM feasibility study of such PVFC system need to be carried
FC for DC electricity generation, and PCU(inverter) for out with model parameters available in manufacturer’s
DC-AC converter purpose have been designed and modeled performance data sheets or measurements obtained from
for conversion of DC power obtainable from renewable
energy sorces to AC power for indian rural house. The
literature.
hydrogen fuel cell serves as the primary power source and In this research work, design model and control strategy
the photo-voltaic cell acts as the secondary power source. If of an autonomous PVFC system has been developed and
the household load is greater than the power produced by simulation test has been performed to validate the
the primary source i.e fuel cell then both PV and FC act system for supply of power to rural house in remote
together to manage the load. The stimulation has been done area where grid is not available. The PV as a standalone
using MATLAB/ SIMULINK. Load sensitivity analysis has may produces electricity to meet the energy
been conducted with varying load as well as insolation and requirement of home load [3]. But during low radiation
the results were found consistant. period, the system require to be integrated with fuel
Keyword : PVFC, Solar Cell, PEM Fuel Cell, DC-AC cell & supplement the load power requirement at user
converter, PEM Electrolyser etc. end. PV cell charges the battery and charges are fed to
electolyser which in turn fed to fuel cell for producing
1. INTRODUCTION electricity. A schematic diagram of the system is shown
in Fig.1. The fuel cell acts as primary source and the
Electricity is the basic need of a human being. The PV cell acts as secondary power supply.
demand of electricity is increasing day by day. On the
other hand the generating capacity of grid power station
is falling due to shoratage of raw materials such as fossil
fuel (Natural gas, petroleum, etc.). Also the products on
their combustion are causing global problems like
greenhouse effect and pollution which are greatest
threats to our environment today[1]. Renewable energy
sources (Solar, wind, FC, etc.) are a few alternative
energy sources. Among all solar PV sources is gaining
popularity due to production of pollution free green
electricity from freely available solar radiation, available
in every corner of country throughout the season.
However due to large variation in solar radiation during
sun hour and large sizing of PV cell, the PV system
needs to be integrated with other sources such as battery
or fuel cell to make it cost effective. The fuel cell power Figure 1: Schematic Diagram of Photo-voltaic Fuel cell
supply is very attractive option to be used in an (PVFC) hybrid system
integrated system along with the PV cell, because the 2. FUEL CELL
fuel cell power system has many attractive features such
as efficiency, fast load-response, modular production The Fuel cell (FC) is an electrochemical device that
and fuel flexibility. The fast response of the fuel cell can produces direct current electricity through the reaction of
solve the photovoltaic’s inherent problem of intermittent hydrogen and oxygen in the presence of an electrolyte.
power generation. Moreover, their high efficiency They are an attractive option for use with intermittent
Volume 1, Issue 2 July-August 2012 Page 216
International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012 ISSN 2278-6856
sources of generation, like the PV, because of high dT= difference between Tcell and Tstc
efficiency, fast load response, modularity, and fuel Ci = current temperature coefficient (1/deg.C)
flexibility. Unlike a battery, a FC does not require = 6e-3/Pstc* Vmpp
recharging. Their feasibility in coordination with PV Cv = voltage temperature coefficient (1/deg.C)
systems can be demonstrated successfully for both grid- = -73e-3/Vmpp
connected or grid deprived a standalone applications.
Other advantages of FC are the re-usability of exhaust The value of STC (Standard Test Conditions) Power per
heat, on-site installation, and diversity of fuels. The fuel unit of area is 76.3W/m2. The value of K (thermal
for the FC can be hydrogen or any other hydrogen- resistance) has been determined to be 0.021 from 5 sec
containing compound, which on reprocessing can produce average value of irradiance over a year. The calculations
hydrogen. The use of electrolysis to produce hydrogen have been carried out on the basis of the standard
from water is an efficient method from very small to very photovoltaic module with the parameters shown in the
large scales. Additionally, when PV is used with the Table. 1 for Solyndra SL-001-150(150 W).
electrolyzer, it is the cleanest source of hydrogen with no
pollutants produced. On the small scale, a PV array Table 1 : Electrical Characteristics
coupled to an electrolyzer and H2 storage tank provides a Sl. Parameter(s) Specifications
flexible system, which could be installed in any location
1 Rated Power Pmpp 150 Wp
in rural India with little maintenance. A single PEM fuel
cell produces a limited voltage, usually less than 1V. In 2 Rated Voltage Vmpp 65.7 V
order to produce a useful voltage for practical 3 Rated Current Impp 2.28 A
applications, several cells are connected in series to form 4 Open Circuit Voltage Voc 91.4 V
a fuel cell stack. The output voltage depends on the 5 Short Circuit Current Isc 2.72 A
6 Temp. Coefficient of Power - 0.38%/˚C
number of the cells in the stack. The PEM electrolyzer
7 Temp. Coefficient of Voltage -0.265 V/˚C
and PEM fuel cell can work in reverse action mode of
8 Series Fuse Rating 23 A
operation.
A Proton Exchange Membrane (PEM) electrolyser
3. MODELLING
Fig.2(a) is used in order to get H2 gas from water [4][5].
In a photovoltaic cell operating in the clamped voltage The temperature of water should be in the range 80-
region, the output voltage of the module is fixed at the 100˚C. The energy required is 500Wh/Nm3 of H2.
operating voltage of the system which is equal to the
battery voltage (+12 V in this case). The global reactions taking place at the electrodes are:
Assuming the module temperature is linearly dependent Anode : 6H2O(l) => O2(g) + 4H3O+(l) + 4e-
on the ambient temperature and power. Cathode : 4H3O+(l) + 4e- => 4H2(g)+ 4H2O(l)
Tcell =Tamb+ K.G (1) The cell half reactions are:
Where, Anode : H2 => 2H+ + 2e-
Tcell : Cell temperature Cathode : ½ O2 + 2H+ + 2e- => H2O
Tamb : Ambient temperature The overall reaction: H2 + ½ O2 => H2O
G : Irradiance W/m2
K : Equivalent thermal resistance
The parametric equation for calculating the module
Power [3] is expressed as :
Pmod = Pstc *((Grel+ L)/ (Grel+ O))*N*Grel (2)
Where,
Grel = G/Gref
Gref = 1000 W/m2
L= 0.001267789
O = 0.025403774
N = (1+O)/ (1+L)
MPP Power corrected by temperature coefficient is given
in equation (3)
Pmpp,corrected = Pmod(1+ Ci.dT)(1+Cv.dT) (3)
Figure 2: (a) A PEM electrolyser (b) PEM Fuel Cell
Where,
Volume 1, Issue 2 July-August 2012 Page 217
International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012 ISSN 2278-6856
Table 2 : PEM Electrolyser
Sl. Parameter(s) Specification 5. POWER CONDITIONING UNITS (PCUS)
1 Type PEM
2 Temperature of Operation 80-100˚C Photovoltaic or Fuel Cell power systems, which generate
3 Pressure of Operation 1-70 bars power as a direct current (DC), require power conversion
4 Electric consumption 500Wh units to convert the power from DC to alternating current
5 Energy efficiency 80-90% (AC). This power could be connected to the transmission
6 Life duration 1,50,000 hours and distribution network of a utility grid or grid deprived
stand alone rural grid. There are other applications,
The obtained H2 is fed to the PEM Fuel cell Fig.2(b)
where it is necessary to be able to control power flow in
which gives the output to the DC-AC inverter for further
both directions between the AC and DC sides. For all
supply to other circuits. The ratings of the PEM hydrogen
these cases power conditioning units are used. Power
fuel cells are given as [6] the specification is reflected in
conditioning units (PCUs) are defined generally as a
Table 3.
Table 3 : PEM Fuel Cell rating
module that transforms DC power to AC power
Sl Parameter(s) Specifications (inverters). Here in this study a power converter of 12 volt
. has been proposed which convert 12 volt DC supply to
1 Fuel cell current rating at 48V 10 A 220 volt 50 Hz approximated sine wave power supply.
2 Fuel cell power rating at 48 V 480 W The THD value of such PSU is very low in the order of
3 Fuel utilization factor 0.9 10% or even low.
4. POWER MANAGEMENT STRATEGY 6. SIMULATION AND RESULTS
In the schematic diagram of the PVFC Solar hybrid The mathematical models of the PVFC Solar hybrid
system as shown in Fig.1, the Photo-voltaic cell acts as system described above have been simulated in MATLAB
the secondary power source. The main motive of the PV 7(2009) version. The simulation consists of the
cell is providing power to the electrolyser for electrolysis temperature variation and its effect on photovoltaic
and production of hydrogen. The Fuel Cell acts as the module to generate power output of the photovoltaic cell
primary power source and is capable to meet the entire during sun hour period (Fig.4). The energy produced by
power needs of a small rural house [7]. The power PV cell is stored in Battery. The output power of the PV
provided by the FC is fed to the DC-AC inverter which system, however, fluctuates specially during cloudy
converts the DC power to the required AC power to meet weather depending on solar insulation and surface
the home load [8][9]. In case of overload, shortage of Temperature. The use of holography film on solar plate
power or failure of fuel cell due to any reason, then the may increase the efficiency of these solar plates.
PV cell provides an emergency backup system. The
secondary battery stores power when the PV cell is not
providing energy to the electrolyser for electrolysis i.e.
when there is sufficient inventory of hydrogen available.
The power flow diagram given below shows the operation
of the PVFC integrated system (Fig. 3)
Then a storage system must be used to deliver the
required power at lower insulation levels and during the
night. The panel surface temperature varies between 20
and 45C during the year.
Figure 5: SOC of Battery
Figure 3: Power Flow diagram of the PVFC Solar hybrid
power system
Volume 1, Issue 2 July-August 2012 Page 218
International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012 ISSN 2278-6856
The photovoltaic module stops supplying power to the solar PV devices, various antipollution apparatus can be
primary battery when the battery is fully charged or the operated such as water purification through electro
H2 storage is full and starts supplying power to the chemical processing and stopping desert expansion by PV
secondary battery. The critical state of charge water pumping with tree plantation. However, control
(SOC_critical) is taken as 40% of SOC. Fig. 5 shows the problems arise due to large variances of PV output power
percentage time for which the SOC is higher than 40%. under different insulation levels. To overcome this
This shows the optimal design of PV as well as battery problem, PV power plants integrated with one such FC
sizing for average load under consideration 480 Wh. system has been proposed in this research study The
It is seen that the photovoltaic cell provides enough power PVFC technology is very promising for delivering clean
for the PEM electrolyser to operate during summer and efficient power for applications in rural areas. With
months but during winter time the power provided by the increased pollution and greenhouse gas emission
PV cell reduces and the primary battery is charged slowly concerns, PVFC serves the needs as an eco-friendly
hence the production of H2 is hampered and so is the technology with no carbon emission. The fuel cell
power supply to the output. So for the winter months, it is provides the PVFC system compactness, it has no moving
suggested that either we use more number of solar panels parts which lead to no combustion in ideal conditions,
or the supply to the electrolyser has to be discontinuous and thus the system can achieve 99.99% reliability. Fuel
for some period of time allowing the primary battery to cells and Photovoltaic cells when used alone are quiet
charge. During that period the emergency load can be inefficient, but when both are integrated they not only
carried out by the secondary battery. The operation of PV reduce the cost but also become more efficient. This
cell is independent of the load and only depends on the technology is very useful power source in remote
availability of irradiance. The load profile of fuel cell is locations where electricity is not available. The PVFC
shown in Fig 6&7. systems have a wide range of application in the rural
areas such as home power supply, pumping sets used in
farms, charging laptops and cellular phones etc. The
power supply may find its application in petrol pump in
remote area. The rural telephone exchange can be
powered from this system. Literacy programme can be
conducted in adult education centres during evening
hours. Village market can be powered through this source
of supply even in late hours of night.
8. CONCLUSION
The simulations and results show that the PVFC Solar
Figure 6: Load Profile of Fuel Cell in Summer hybrid system is capable of performing well in meeting
the external load using the energy produced by the
system. The power supplied by the Fuel Cell is DC which
is converted to AC by the inverter as the power required
by the household appliances is AC signal. The PVFC
system is economically feasible as the production of
power is dependent on two sources and the life time
expectancy of both the sources is relatively higher as
compared to conventional power sources. This system is
easy to install, easily available and relatively easier to
handle. Thus we can say that the PVFC Solar hybrid
system should serve as a reliable viable power source in
Figure 7: Load Profile of Fuel Cell in Winter rural areas.
7. APPLICATION OF PVFC SYSTEM
REFERENCES
Renewable energy sources (solar, wind, etc) are [1] T.Veziroglu, “Hydrogen Energy System: A Permanent
attracting more attention as alternative energy sources to Solution to Global Problems”, Clean Energy Research
Institute, USA, 2004. http://www.iahe.org/hydrogen energy
conventional fossil fuel energy sources. This is not only system.htm
due to the diminishing fuel sources, but also due to [2] D.Mayer, R.Metkemeijer, S. Busquet, P.Caselitz, J.Bard,
environmental pollution and global warming problems. and et al, Photovoltaic/Electrolyser/fuel cell hybrid system
Among these sources is the solar energy, which is the the Tomorrow Power Station for Remote Areas, 17th
most promising, as the fabrication of less costly PV EPVSEC, Munich Germany, pp.2529-2530, 2001.
devices becomes a reality. With increased penetration of
Volume 1, Issue 2 July-August 2012 Page 219
International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012 ISSN 2278-6856
[3] D.S. Kim, A.M. Gabor, V. Yelundur, A.D. Upadhyaya, V.
Meemongkolkiat, A. Rohatgi. "String ribbon silicon solar
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1296, 2003.
[4] A.R.Balkin, “Modelling A 500W Polymer Electrolyzer
Membrane Fuel Cell”, Bs.D, University of Technology,
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[5] F.Barbir, T.Gomez, “Efficiency and Economics of Proton
Exchange Membrane (PEM) Fuel Cells”, Int. J. Hydrogen
Energy, Vol.22, No.10/11, pp.1027-1037, 1997.
[6] G.Hoogers, Fuel Cell Technology handbook, CRC Press
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[7] ASME 8th International Fuel Cell Science, Engineering &
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[8] S.Busquet, R.Metkemeyer and D.Mayer: “Development of
a Clean Stand-alone Power System Integrating PV, Fuel
Cell and Electrolyser”, Proc. Of the Photovoltaic Hybrid
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[9] J.Benz, B.Ortiz, W.Roth, and et al, “Fuel Cells in
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AUTHORS
Dr S.N. Singh had completed doctoral PhD
degree at the Department of Electrical
Engineering, National Institute of Technology
Jamshedpur (India). He obtained his B.Tech
degree in Electronics and communication
engineering from BIT Mesra (A Deemed university), Ranchi -
Jharkhand (India) in 1979/80. Presently his area of interest is
solar energy conversion technology. He had published more
than 50 papers in National and International journals based on
his research work. He had remained Head of Department of
Electronics and Communication Engineering for two terms and
presently heading Govt. of India sponsored VLSI SMDP-II
Project.
Preeta John graduated in Electrical
Engineering from T.K.M College of
Engineering, (Kerala University) Kollam,
Kerala - India and post-graduated in Power
Electronics from National Institute of
Technology Calicut, Kerala - India. Her areas of
interest are soft switched DC-DC and DC-AC
converters and Renewable energy sources. She is currently
heading the Electronic department at NTTF at R D Tata
Technical Education Centre, Jamshedpur.
Navneet Prabhakar is pursuing B.Tech
(Hons) in Electronics and Communication
Engineering from National Institute of
Technology, Jamshedpur (India). His area of
interest is non conventional energy sources
and their development. He has completed
several projects on VLSI based control system .
Volume 1, Issue 2 July-August 2012 Page 220
