i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 4 ( 2 0 0 9 ) 5 2 4 2 – 5 2 4 8

Avai lab le at www.sc iencedi rect .com

journa l homepage : www.e lsev ie r . com/ loca te /he

Design of a PEM fuel cell system for residential application

Muhsin Tunay Gencoglu*, Zehra Ural

Department of Electrical and Electronics Engineering, Faculty of Engineering, Firat University, 23119 Elazig, Turkey

a r t i c l e i n f o

Article history:

Received 2 September 2008

Accepted 19 September 2008

Available online 12 November 2008

Keywords:

PEM fuel cell

Hydrogen energy

Residential application

* Corresponding author. Fax: þ90 4242415526E-mail addresses: mtgencoglu@firat.edu.t

0360-3199/$ – see front matter ª 2008 Interndoi:10.1016/j.ijhydene.2008.09.038

a b s t r a c t

Fuel cells are energy transformation technologies and they are clean, don’t damage to

environment, have high efficiency and provide uninterruptible energy generation.

Research and development studies about fuel cells have been done increasingly. In the

recent years, fuel cell technologies have performed in some sectors such as military,

industrial, space, portable, residential, transportation and trading.

Uninterruptible energy is becoming necessary because of high standard of living,

increasing of energy demand of residence. Therefore, there is a need for the systems

which will provide required energy if the fuel cell is unconnected to grid and the systems

will operate as reserve system when the fuel cell connect grid. A fuel cell system worked by

hydrogen can be used for the need. Otherwise, hydrogen energy utilization at residences is

an alternative method especially for supply power demand of stationary or portable

devices. In this paper, hydrogen energy and fuel cells were investigated and application

areas of fuel cell systems were researched. In addition, design of a fuel cell system was

achieved and the components of the system were defined for the residential application

which one of the application areas of fuel cell systems.

ª 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights

reserved.

1. Introduction constraints. Among the various types of distributed genera-

The Fuel Cell concept is more than 150 years old. William

Grove firstly exposing the fuel cell concept, have the idea to

study the opposite process of the electrolysis. Fuel cell

denomination arises in 1839, created by Ludwig Mond and

Charles Langer. The first successful implementation was in

1932 by Francis Bacon. Since the fifty’s fuel cell developed by

NASA has been used as electric generators for the space

shuttles. Nowadays there are many big companies investing

a lot of money to the fuel cell technology success, especially

automobile industry [1,2].

Considerable attention has been devoted to distributed

sources of energy for meeting the power demand instead of

constructing new conventional power plants due to better

power quality, reliability, portability and ecological

.r (M.T. Gencoglu), zural@ational Association for H

tion, fuel cells generated tremendous interest for electricity

and heat generation due to their low operating temperature,

fast start up characteristics, and ecological constraints [3].

Fuel cell power plants (FCPPs) are electrochemical devices

that convert the chemical energy of a reaction directly into the

electrical energy. Among the various next generation power

plants, the FCPPs has been found to be one of the most

promising energy sources due to high efficiency and envi-

ronment-friendly operation [4]. Because fuel cells convert the

fuel to electricity through an electrochemical process rather

than a combustion process typical of most power plants, the

emissions are much cleaner. Compared to burning fossil fuels

like coal and oil, which produces emissions of sulfur dioxide,

nitrogen oxide, and carbon dioxide, the electrochemical

process used in fuel cells only has carbon dioxide and water as

firat.edu.tr (Z. Ural).ydrogen Energy. Published by Elsevier Ltd. All rights reserved.

i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 4 ( 2 0 0 9 ) 5 2 4 2 – 5 2 4 8 5243

by products. The low emissions from fuel cells make them an

environmentally preferred form of power production. The use

of FCPPs is expected to become more widespread in the near

future, in spite of their high current capital cost [5]. However,

it should be emphasized that the first generation of fuel cells

will likely operate on natural gas or propane, which are finite

fossil fuels whose extraction from the ground and delivery

produce negative environmental impacts. In the future, fuel

cells will run on gas derived from biomass or pure hydrogen

extracted from water using wind or solar energy, thus playing

a key role in ushering in a sustainable energy future.

In the recent years there was an increasing interest in fuel

cell technology and fuel cells have reached a high develop-

ment status. This development was mostly advanced by the

automotive industry, because fuel cells are suitable to

substitute the fossil fuels and also to provide an environment-

friendly propulsion. But there is also a growing market for

stationary fuel cell applications, e.g. for cogeneration of heat

and power, and as a substitute for batteries in portable

devices, e.g. for laptops.

Despite the progress made in first realized fuel cell vehicle

fleets and combined heat power units there is still lot of work to

be done to bring fuel cells to the market. The reduction of still

high costs has the biggest priority but the build up of hydrogen

infrastructure is not less important. Furthermore, the durability

and reliability of conventional systems has to be reached. By

means of mathematical modeling the development and design

of fuel cell systems can be highly accelerated [6].

2. Hydrogen energy and fuel cells

Hydrogen is the lightest, the simplest, and one of the most

abundant elements in nature. However, since it is not as a free

element, different production methods are required to extract

pure hydrogen from its natural form using advanced tech-

nologies that are still in research and development stages.

Fossil or renewable energy sources may be used for the

production process. Once generated, hydrogen may be used as

a fuel for transportation, a source for electricity and heating

[7]. The conversion of world energy system to hydrogen as

a fuel vector is logical when one looks at historical energy

production sequence from wood to coal, from coal to oil and

from oil to natural gas [8]. In this context, the optimal

endpoint is the replacement of hydrogen for the present fossil

fuels [9]. In addition, a worldwide transition from fossil fuels

to hydrogen would eliminate many problems such as climate

change, global warming, urban air pollution and their ramifi-

cations [7–10]. Using hydrogen as an alternative energy

resource is expected to be a method for remedying the energy

and environmental problems mentioned above. Hydrogen

energy system is a continuous, renewable, sustainable and

efficient system in harmony with the environment [11].

Fuel cell converts chemical energy of hydrogen into

electrical energy. As a result of this conversion just water and

heat are produced as waste. Fuel cells have advantages like

being environmentalist, having less moving parts and not

requiring maintenance continuously [12]. In a fuel cell,

hydrogen is fed at the anode, oxygen is fed at the cathode,

and an electrolyte is sandwiched between the two electrodes

for conveying ion e� from the anode to the cathode. Elec-

trons are carried to the cathode through both anode and

a conducting wire, and a load is placed in between. There are

many auxiliary devices needed to operate the FCPPs, which

takes part in the gas and electricity management and are

used for regulating the parameters such as reactant flow rate,

total pressure, reactant partial pressure, temperature and

membrane humidity at a desired value to ensure that FCPPs

can run smoothly without getting the stack either flooded or

drying out [13]. Accordingly, any malfunctioning, perfor-

mance loss, and/or failure in these auxiliaries can reduce the

overall performance of the FCPPs [5].

There are many types of fuel cell, classified according to

the electrolyte type (a liquid solution, a solid membrane or

even ceramic) [1,14,15]. The fuel cell electrolyte type has

a strong relation with fuel cell temperature operation. Liquid

electrolytes are more suitable for low temperatures operation,

instead of ceramic electrolytes used for high temperature fuel

cell [2]. Fuel cells are categorized based on the type of elec-

trolyte used. Generally, there are six basic types of fuel cells:

Alkaline fuel cell (AFC), proton exchange membrane or poly-

mer (electrolyte membrane) fuel cell (PEMFC), phosphoric acid

fuel cell (PAFC), molten carbonate fuel cell (MCFC), solid oxide

fuel cell (SOFC) and direct methanol fuel cell (DMFC). Although

different types of fuel cells have been developed, PEM fuel

cells are well suited for many applications including auto-

mobiles, buildings, and for smaller applications [15–18].

Some of the popular type of fuel cells and their character-

istics are listed on Table 1.

2.1. PEM fuel cell

Fuel cells basically convert chemical energy of hydrocarbon

fuels directly into dc form of electrical energy. A FCPP mainly

consists of a fuel-processing unit (reformer), fuel cell stack

and power-conditioning unit. The fuel cell uses hydrogen as

input and produces dc power at the output of the stack. A

simple representation of a fuel cell system is shown in Fig. 1.

The performance of a fuel cell is generally characterized by

using the polarization curve, which is a plot of the fuel cell

output voltage as a function of load current. The polarization

curve is computed by using the Tafel equation [21], which

subtracts the various voltage losses from the open circuit dc

voltage, and is expressed as

Vstack ¼ Vopen � Vohmic � Vactivation � Vconcentration (1)

where,

Vopen ¼ N0

�E0 þ E1

�¼ N0

"� Dg0

f

2Fþ RT

2Fln

pH2

ffiffiffiffiffiffiffiffiffipO2

ppH2O

!#(2)

Vohmic ¼ ðiþ inÞRFC ¼ IdcRFC (3)

Vactivation ¼ N0RT2aF

ln

�Idc

I0

�(4)

Vconcentration ¼ �cln

�1� Idc

ILim

�(5)

Table 1 – Comparison of different fuel cells and their operating characteristics [19,20].

Fuel cell type AFC PEMFC DMFC SOFC PAFC MCFC

Operating temperature (�C) 660–250 80–100 50–90 750–1000 160–250 z650

Electrolyte Liquid Solid Solid Solid Liquid Liquid

Efficiency (%) 50–70 35–60 35–40 45–60 35–50 40–55

Applications Transportation, space, military; Energy storage systems,

Portable power systems, Decentralized stationary systems

Combined heat and power for; Decentralized

stationary systems, Transportation

i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 4 ( 2 0 0 9 ) 5 2 4 2 – 5 2 4 85244

In the above equations, N0 is the cell number, V0 is the open

cell voltage, R is the universal gas constant, T is the temper-

ature of the fuel cell stack, F is the Faraday’s constant, pH2 is

the hydrogen partial pressure, pH2O is the water partial

pressure, pO2 is the oxygen partial pressure, pO is the standard

pressure, a represents the charge transfer coefficient of the

electrodes, Idc is the current of the fuel cell stack, ILim is the

limiting current of fuel cell stack, I0 is the exchange current of

fuel cell stack and c is the empirical coefficient for concen-

tration voltage. The steady state voltage for one cell (N0¼ 1)

and power versus cell current density is obtained based on Eq.

(1) [5].

PEM fuel cells have gained international attention as

candidates for alternative automotive and stationary power

sources due to features such as their adaptable size and low

operating temperatures [22–24]. The electrolyte of PEMFC, as

the name suggests, is a polymeric membrane/film [22]. The

typical operation temperature of PEMFCs is in the range of 80–

100 �C [25].

3. The applications of fuel cells

Fuel cells are one of the most promising technologies for

delivering clean and efficient power for automotive and resi-

dential applications. With increased urgency in reducing

pollution and greenhouse gas emissions, a resurgence of

interest in fuel cells has occurred. Today, governments and

many corporations are making massive investments into the

development of these clean power sources. Although fuel cells

hold great promise for clean, inexpensive power, they are still

in their developmental infancy, and a great deal of research is

necessary before they are considered as viable power systems

[26]. Test capabilities that deliver reliable monitoring and

control, and offer the benefit of a flexible configuration, are

Fuel CPoweStack

FuelProcessorNatural

Gases

H2

Steam

Air

Heat and W

Fig. 1 – Basic fuel ce

critical to these advances. The capabilities will permit scien-

tists to easily tailor their systems to keep in pace with the

evolving fuel cell technology [19].

Fuel cells are very useful as power sources in remote

locations, such as spacecrafts, remote weather stations,

parks, rural locations, and in certain military applications. A

fuel cell system running on hydrogen can be compact, light-

weight and has no major moving parts. Because fuel cells have

no moving parts, and do not involve combustion, in ideal

conditions they can achieve up to 99.99% reliability [27]. There

are a wide ranges of applications which are listed below [28].

1. Stationary power applications

� Power generating stations

� Auxiliary units

� Distributed power generation

� Residential use as combined heat and power generation

system

2. Transportation applications

� Buses, track and cars

� Airport intra-terminal vehicles

3. Portable applications

� Laptops

� Cellular phones

3.1. Stationary power systems

Stationary power products range from 1 kW to several mega-

watts. Applications include any place homes, businesses,

schools, hospitals, etc. These markets are typically served by

central generation. Another technique to serve the stationary

market is the employment of hydrogen turbines. The only

byproduct of burning hydrogen in oxygen is water that is free

from CO2, NOx, and SOx emissions [20].

ellr

DC/ACPower

InverterDC Power AC Power

ater

ll components.

i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 4 ( 2 0 0 9 ) 5 2 4 2 – 5 2 4 8 5245

Residential fuel cell systems can be operated to provide

primary or backup power for the home. They can run inde-

pendently or in parallel to an existing power grid. A fuel cell

power system for a residence could be located in the basement

or backyard, taking up about as much space as an ordinary

refrigerator, and providing clean, quiet, reliable power.

Residential fuel cell systems can produce about 5 kW of

power or 120 kW h of energy a day. A lack of performance data

on how well fuel cells work under different conditions is one

of the several factors slowing marketplace acceptance of the

new technology. There are several companies currently

working on residential fuel cells. Demonstration units are

being tested around the country by fuel cell manufacturers in

cooperation with local governments and/or utilities.

There are many problems which will be solved in resi-

dential fuel cell system. These problems are fuel reformer,

cost, heating time, method, storage and carrying of hydrogen,

economic hydrogen production, cogeneration system and

waste of CO2.

3.2. Transportation

One of the earliest applications of PEM fuel cells was the

General Electrical Corporation built 1 kW Gemini power plant

used on the Gemini spacecrafts built in the early 1960s. The

performance and life of the Gemini fuel cells were largely

limited by the membrane used at the time. Since then, cell

performance and power levels have increased significantly.

For high power densities it is necessary to minimize weights

and volumes of fuel cell systems for marine, space, and

terrestrial applications. There are many companies working

to develop fuel cells for transportation applications: Ballard

Power Systems and Perry Energy have developed a Perry PC-14

unmanned underwater vehicle with a 3 kW PEM fuel cell stack

operating on hydrogen and oxygen cylinder gases. Treadwell

Corporation developed a 1 kW 34 - cell PEM fuel cell stack with

an operating range of 1.3–2 h at top speed.

The development of fuel cell powered submarines has

been investigated for over a decade by German companies.

Some corporations are investigating the application of PEM

fuel cells for air independent propulsion in submarines. These

submarines will require 300–400 kW for a PEM fuel cell battery

hybrid system to store an energy of 100–200 MW h. Burlington

Northern Corporation and General Electric Transportation

Systems are investigating fuel cells as an alternative power

source for locomotives. A PEM fuel cell system developed by

Analytic Power Corp. System will operate on diesel fuel and

air. Analytic Power is currently developing a 10 kW DC power

plant consisting of 56 PEM fuel cells.

Ballard Power Systems has developed the first zero-emission-

vehicle fuel cell bus. The 20-passenger bus requires a power of

100–120 kW with 24 stacks of 35 cells each currently operating on

hydrogen cylinder gas and an air compressor. The bus has

a range of 160 km with an acceleration of 0–50 km/h in 20 s and

a top speed of 70 km/h. The next stages in development will

increase the passengers capacity and travel range by improving

hydrogen storage and fuel cell performance.

Energy Partners are developing a zero-emission electric

vehicle ‘‘EP Green Car’’ using a PEM fuel cell battery hybrid

system. The 15 kW fuel cell system consists of 3 stacks with

a total of 180 cells which will operate on hydrogen and air at

2.4 atm producing a stack voltage of 125 V at 120 A. General

Motors Co. is developing an indirect methanol–air PEM fuel

cell system with two 40 kW stacks. Ford Motor Co. is also to

develop a PEM fuel cell system for vehicles. In the first stage of

development, the company is to develop a 10–15 kW system

fuelled by hydrogen at 2.0 atm and weighing less than 4 kg/

kW. The ultimate goal is to produce a 50 kW system at less

than 3 kg/kW [29].

In automotive applications PEM fuel cells appear to be most

suitable, because their working conditions at low temperature

allow the system to start up faster than those Technologies

using high temperatures fuel cells; moreover the solid state of

their electrolyte (no leakages and low corrosion) and their high

power density make them fit for transport applications [30].

3.3. Portable fuel cells

Applications include any system that requires power and is

not connected to an electrical outlet such as cameras, cell

phones, laptop computers, radios, electronic devices, power

tools, etc. The portable market has diverse requirements: long

run times, low weight, short response times, long life, low

cost, small physical size and safety and reliability.

Fuel cells have lacked commercialization due to high cost

and identification of a proper market application. The new

emerging handheld video communication and multimedia

devices that demand more power and energy will be a prime

market for fuel cell based portable power products as opposed

to batteries. There are, however, many current opportunities

for the application of fuel cells in small vehicles such as bikes

and motor scooters [20].

4. The residential application

Improving life quality and more dependency for electricity in

houses raises the demand for uninterrupted power systems.

For these reasons we need power systems which can work as

backup power while connected to the grid, or main power

system for places outside the grid. Fuel cell system powered

by hydrogen is a suitable candidate for this aim by its prop-

erties like high efficiency, quite, low emission, low mainte-

nance need. Fuel cell system can be driven by direct hydrogen

or by fuels like natural gas and a reformer. Beside the main

electric output of the system, by using the waste heat the hot

water need for house can be obtained. So the total system

efficiency will be increased.

In this section, a hybrid system consists of photovoltaic

panels and fuel cells were designed for a residence to supply

electrical demand. DC voltage obtained by photovoltaic panels

has been stored in batteries with charge regulators. The

voltage has been used in electrolysis unit which will generate

hydrogen used by fuel cell, as shown in Fig. 2. Hydrogen

obtained by electrolysis is stored in hydrogen tanks. DC

voltage obtained from fuel cell is converted to AC voltage and

electrical demand of the residence is supplied.

The photovoltaic system includes totally 20 PV modules

and the total installed power is 2.5 kWp in the standard

conditions (values correspond to 1000 W/m2, 25 �C and the

Chargeregulator

Batteries

Elektrolyser

Hydrogentank

DC/ACinverter

PEMfuel cell

PVpanels

Demiwater

12 V DC/220V 50 Hz AC

30A /12/24V DC

12V – 350 Ah8 units

H2O

H2 AC

H2

DC

5-7 m3~(0.4-0.6 kg)

DC

1.05 Nm3 H2/hPEM type

O2

1.2 kW x 4units(4.8 kW)

125Wx20 modules(2.5 kW)

Fig. 2 – Block diagram of the hybrid system.

Washing machine 2.5 kW

Dishwasher 2.5 kW

Cooker 2 kW

Outlet line 1.8 kW

Outlet line 1.8 kW

Lightning line 0.5 kW

Lightning line 0.5 kW

i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 4 ( 2 0 0 9 ) 5 2 4 2 – 5 2 4 85246

total installed power 1.5 air mass). The specifications of the

solar modules are determined as follows: maximum power is

125 W, maximum output voltage is 17.42 V, maximum output

current is 7.2 A, open circuit voltage is 22 V and short circuit

current is 7.62 A.

DC charge regulators of 30 A/12/24 V are used in this

system. DC energy obtained from photovoltaic panel groups

has been stored in 8 units of solar battery such that each unit

has 12 V to 350 Ah.

Electrolysis is a reaction, which produces hydrogen and

oxygen from water. The electricity required for this reaction

can be supplied from a renewable source. A PEM type elec-

trolyser is used to produce hydrogen by utilizing the electricity

generated by the PV panels. The net hydrogen production rate

of the electrolyser is 1.05 Nm3/h with a delivery pressure of

maximum of 13.8 bar. The purity of the product hydrogen is

99.9995% and the power consumed per volume of hydrogen

produced is 6.7 kW h/Nm3 for optimal conditions. The elec-

trolyser is for indoor use for ambient temperatures ranging

from 5 �C to 40 �C, so the required ventilation and climatiza-

tion according to its requirements should be established

before the operation. The electrolyser is air-cooled and the

heat load from the system is maximum of 4.3 kW. The elec-

trolyser uses deionized water to produce hydrogen and to

actively cool the cell stack [31].

Hydrogen obtained from electrolysis is stored at metal

hydride tanks. Solid phase hydrogen storage is considered to

be the most futuristic storage techniques. This technique is

very advantageous because of providing the safe handling of

hydrogen and convenience with mobile applications.

Hydrogen storage as metal hydride is one of the solid phase

techniques [31].

Fuel cells are utilized to generate electrical energy from

hydrogen stored in hydrogen tanks. The PEM fuel cells have an

compact structure, easiness and simple maintenance, for this

reason PEM fuel cell was chosen in this system. The used Nexa

fuel cell modules generate irregular DC power of maximum

1.2 kW. Nominal output voltage is 22–50 V DC. These fuel cells

use the air as oxidant and output of the fuel cell is DC power,

water, heat and unused air. Each module of Nexa PEM fuel cell

has features such as, output power is 1.2 kW (total 46 A and

22–50 V DC), hydrogen utilization purity of 99.99%, hydrogen

consumption is �18.5 l/min, maximum water emission is

870 ml/h, hydrogen input pressure is range of 0,7–17 bar [32].

Outputs of the fuel cells are parallel-connected and the

outputs are constituted input of an inverter.

Power demand of the residence is calculated as

The total installed power of the residence is 11.6 kW.

According to Guide of Electrical Internal Installations in

Turkey, while synchronous power of an apartment is defined,

synchronism coefficients must be considered in following:

� 60% for section of 8 kW of the set up power

� 40% for remainder section of the total power

If the synchronism coefficient is considered for this total

power as suitable Guide of Electrical Internal Installations,

using power at the same time is 8� 0.6þ 3.6� 0.4¼4.8þ 1.4¼ 6.24 kW. So a power of 6.24 kW is sufficient for this

residence. The total power of the hybrid system is 7.3 kWp

consists of power of PV panels (2.5 kWp) and PEM fuel cells

(4.8 kWp).

i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 4 ( 2 0 0 9 ) 5 2 4 2 – 5 2 4 8 5247

5. Conclusions

Another way of using hydrogen in our houses is gaining power

for stationary or portable devices in our houses. Especially

portable devices like vacuum cleaner can be attractive. It is

possible to provide longer working hours for electronic

devices like laptops, palms, and mobile phones. The customer

demand in this area, which is ready to pay more for energy,

makes the marketing more possible. Bicycles, scooters, wheel

chairs may be other marketing areas. The most important

problem for using hydrogen powered fuel cells that have lots

of technical advantages in our houses is their costs. This

problem can be solved by the improvements in technology,

increasing demand and starting of mass production. For

portable devices weight and dimensions must be comparable

with the existing designs. Building a reliable and global

infrastructure for hydrogen must be the main goal for reach-

ing the customer.

Electrical energy production from renewable energy sources

except hydroelectric energy is done mainly for local and small

applications in Turkey. It must be concentrated applications of

electrical energy production from hydrogen which is to be

accepted fuel of the future. The researches and projects related

to applications of residential fuel cells must be supported.

Before the institutions which will be energized with

renewable energy sources was not built, total energy

requirement of the institution and suitable energy sources

(photovoltaic panel, wind turbine or fuel cell) must be defined

and calculation of power is done.

r e f e r e n c e s

[1] U.S. Department Of Energy. Fuel Cell Handbook. 5th ed.EG&G Services, Parsons, Inc., Science ApplicationsInternational Corporation; 2000.

[2] Henrique MBS, Vicente MC, Marcal P, Carla MNA, Jose WMK.Development and test of hydrogen proton exchangemembrane fuel cell prototypes. In: second internationalhydrogen energy congress and exhibition, IHEC 2007,Istanbul, Turkey; 13–15 July 2007.

[3] Larmine JE, Dicks A. Fuel cell systems explained. Chichester,England: John Wiley and Sons; 2000.

[4] Uzunoglu M, Onar OC, Alam MS. Dynamic behavior of PEMFCPPs under various load conditions and voltage stabilityanalysis for stand-alone residential applications. Journal ofPower Sources 2007;168:240–50.

[5] Tanrioven M, Alam MS. Impact of load management onreliability assessment of grid independent PEM fuel cellpower plants. Journal of Power Sources 2006;157:401–10.

[6] Lemes Z, Vath A, Hartkopf Th, Mancher H. Dynamic fuel cellmodels and their application in hardware in the loopsimulation. Journal of Power Sources 2006;154:386–93.

[7] Yuzugullu E, Deason JP. Structuring objectives to facilitateconvergence of divergent opinion in hydrogen productiondecisions. Energy Policy 2007;35(1):452–60.

[8] Muneer T, Asif M. Prospects for secure and sustainableelectricity supply for Pakistan. Renewable and SustainableEnergy Reviews 2007;11(4):654–71.

[9] Momirlan M, Veziroglu TN. The properties of hydrogen asfuel tomorrow in sustainable energy system for

a cleaner. International Journal of Hydrogen Energy 2005;30:795–802.

[10] Akaya AV. Modeling and simulation of hydrogen fed SOFC-GT hybrid system. In: second international hydrogen energycongress and exhibition, IHEC 2007, Istanbul, Turkey; 13–15July 2007.

[11] Kıykım CC, Gencoglu S, Unal E. The role of defense industryin hydrogen technologies evolution. In: second Internationalhydrogen energy congress and exhibition, IHEC 2007,Istanbul, Turkey; 13–15 July 2007.

[12] Aydin M, Sisman A. 2D modeling of a PEM fuel cell. In:second international hydrogen energy congress andexhibition, IHEC 2007, Istanbul, Turkey; 13–15 July 2007.

[13] Pukrushpan JT, Stefanopoulou A, Peng H. Modeling andcontrol for PEM fuel cell stack system. In: proceedings of the2002 American Control Conference, Anchorage, AK; May2002. p. 3117–22.

[14] Booth D. Understanding fuel cells. Home Power 1993;35:37–40.

[15] Wolk HR. Fuel cells for homes and hospitals. IEEE Spectrum1999;36(5):45–52.

[16] Rajashekara K. Hybrid fuel-cell strategies for clean powergeneration. IEEE Transactions on Industry Applications May/June 2005;41(3).

[17] Blomen LJMJ, Mugerwa MN. Fuel cell systems. Plenum Press;1993.

[18] Pecen RR, Yildiz F, Baltaci K. Development of a DATAacquisition and interface module for a 500 W hydrogen fuel-cell power station using LabView� PDS v8.20. In: secondinternational hydrogen energy congress and exhibition, IHEC2007, Istanbul, Turkey; 13–15 July 2007.

[19] Hoogers G. Fuel cell technology handbook. Boca Raton, FL:CRC Press; 2003.

[20] Shahrokhi F, Nasab A, Guarnaccia R. Innovative applicationsof hydrogen fuel cells. In: second international hydrogenenergy congress and exhibition, IHEC 2007, Istanbul, Turkey;13–15 July 2007.

[21] Thirumalai D, White RE. Mathematical modeling of proton-exchange membrane fuel-cell stacks. Journal ofElectrochemical Society 1997;144:1717–23.

[22] Zalbowitz M, Thomas S. Fuel cells: green power. Departmentof Energy; 1999. LA-UR-99–3231.

[23] Dhathathreyan KS, Sridhr P, Sasikumar G, Ghosh KK,Velayuthan G, Rajalakshmi N, et al. Development of polymerelectrolyte membrane fuel cell stack. International Journal ofHydrogen Energy 1999;24:1107–15.

[24] Korgesch K, Simader G. Fuel cells and their applications.Weinheim: Wiley-VCH; 1996.

[25] Carrette L, Friedrich KA, Stimming U. Fuel cells-fundamentals and applications. Fuel Cells 2001;1(1):5.

[26] Prabha RA. An advanced fuel cell simulator. Master ofscience thesis. B.E. College of Engineering: Texas A & MUniversity; 2004.

[27] The online Fuel Cell Information Resource. Fuel cell basicsand benefits. Available from: <http://www.fuelcells.org/basics/benefits.html> [accessed 04.07].

[28] Hurley P. Build your own fuel cells. Illustrations and e-bookdesign. Wheelock Mountain Publications, Good idea CreativeServices; 2005.

[29] ] Amphlett JC, Mann RF, Peppley BA, Roberge PR,Rodrigues A. A practical PEM fuel cell model forsimulating vehicle power sources. Battery Conference onApplications and Advances. In: Proceeding of the tenthannual, IEEE 1995.

[30] Pukrushpan JT, Stefanopoulou AG, Peng H. Control of fuelcell power systems: principle, modeling analysis andfeedback design. Advances in Industrial Control, ISBN1852338164; 2004.

i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 4 ( 2 0 0 9 ) 5 2 4 2 – 5 2 4 85248

[31] Ersoz A, Sarıoglan A, _Ilhan N, Ozyonum GN, Cubukcu M,Kaytaz AS, et al. Hydepark A standalone renewable hydrogendemonstration park in Turkey. In: second internationalhydrogen energy congress and exhibition, IHEC 2007,Istanbul, Turkey; 13–15 July 2007.

[32] Cetin E, Aktekin Y, Oner Y, Kasxıkcı _I, Colak M, Ozturk HK.Yenilenebilir enerji kaynakları ile enerjilendirilen birkonutun elektriksel bazda projelendirilmesi. FirstEngineering and Technology Symposium: Ankara, Turkey;April 2008. 235–247.