Performance analyses of Cu–Cl hydrogen production integrated solar parabolic trough collector system under Algerian climate

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Performance analyses of CueCl hydrogen production integrated solar parabolic trough collector system under Algerian climate Malika Ouagued a,*, Abdallah Khellaf b, Larbi Loukarfi c a

Sciences and Technology Department, Faculty of Technology, University UHBC of Chlef - B.P. 151, Chlef 02000, Algeria b Centre de D
eveloppement des Energies Renouvelables CDER - BP. 62, Avenue Observatoire Bouzar
eah, Algiers, Algeria c Mechanical Department, University UHBC of Chlef - B.P. 151, Chlef 02000, Algeria

article info

abstract

Article history:

The potential of hydrogen production by thermochemical cycle in Algeria using solar ra-

Received 3 January 2017

diation as heat sources is estimated under the climate conditions of the country. The study

Received in revised form

analyzes an integrated copperechlorine (CueCl) thermochemical cycle with solar parabolic

14 August 2017

trough system for hydrogen production. In order to determine the most promising solar

Accepted 6 November 2017

sites available for deploying the integrated system, the direct normal solar irradiance (DNI)

Available online xxx

for horizontal tracking system oriented in North-South has been estimated and compared for different locations. Heat gain from parabolic trough collector model is evaluated under

Keywords:

Algerian conditions. To describe the different steps of the CueCl cycle for hydrogen pro-

Copper chlorine thermochemical

duction, we perform a thermodynamic analysis accounting for relevant chemical reactions

cycle

and including the determination of the energy necessary to the cycle. A parametric study is

Hydrogen production

conducted to investigate the effect of heat gain from the parabolic trough collector (PTC) on

Algerian climate

the hydrogen production rate. Furthermore, the rate production of hydrogen by the CueCl

Parabolic trough technology

cycle is analyzed and compared for performance improvement of the system for different

Direct normal solar irradiance

climatic regions in Algeria. Simulation results reveal great opportunities of hydrogen production using CueCl cycle combined with solar PTC in the south of Algeria with annual hydrogen production exceeds 84 Tons H2/year (around 0,30 kg/m2/day). © 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Introduction Energy occupies a significant position in all human activities. Energy sources have evolved and each new energy source has given fresh impulse to social, technological and economical changes [1]. Hydrogen is a sustainable and clean energy

carrier. It is widely expected to be the world's next-generation fuel [2]. Hydrogen can be converted with high efficiency to electricity in a fuel cell without any pollutant emission to air except water vapor. In addition, hydrogen has advantageous properties as an energy carrier including being convenient to use, transport and store, and being produced from a widely available raw material as water. Environmental harm does not

* Corresponding author. E-mail addresses: [email protected] (M. Ouagued), [email protected] (A. Khellaf), [email protected] (L. Loukarfi). https://doi.org/10.1016/j.ijhydene.2017.11.040 0360-3199/© 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved. Please cite this article in press as: Ouagued M, et al., Performance analyses of CueCl hydrogen production integrated solar parabolic trough collector system under Algerian climate, International Journal of Hydrogen Energy (2017), https://doi.org/10.1016/ j.ijhydene.2017.11.040

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Nomenclature Cf ExdesI ExdesII Exelec ExH2 Exin Ff (h-h0)i Iba L QI QII i Qaconv

i Qarad

Qasol

HTF specific heat in segment “i”, (J/kg.K) destruction exergy in the hydrolysis step, kJ/mole H2 destruction exergy in the O2 production step, kJ/ mole H2 exergy associated with electricity work, kJ/mole H2 exergy content of hydrogen, kJ/mole H2 exergy input to the process that enters with the reactants plus heat, kJ/mole H2 HTF flow rate, (m3/s) molar enthalpy change of the substance i, kJ/mol Direct normal irradiance per unit of collector area, (W/m2) Receiver length, (m) heat flow into the hydrolysis step (negative for exothermic reactions), kJ/mole H2 heat flow into O2 production step (negative for exothermic reactions), kJ/mole H2 Convection heat transfer rate for receiver segment “i” between the surface of the absorber to the surface of the envelope, (W) Radiation heat transfer rate for receiver segment “i” between the surface of the absorber to the surface of the glass envelope, (W) Direct incident solar irradiance absorption rate into the receiver segment “i”, (W)

occur when hydrogen is used, provided it is produced from environmentally benign energy sources [3,4]. The effectiveness of hydrogen in addressing the challenges posed by the use of fossil fuels lies in its production method. Extensive research on ways to meet potential hydrogen demands is being conducted, mainly focusing on effective ways to produce hydrogen. Sources of energy are needed from which hydrogen can be produced in large quantities, in an environmentally benign manner and at low cost. Thermochemical cycles are alternative and potentially more efficient methods to produce hydrogen from water splitting [5,6]. Thermochemical cycles are processes that primarily make use of heat and a series of intermediate chemical reactions to break down water into hydrogen and oxygen [5]. This route of hydrogen production uses solar heat at high temperatures for the endothermic steps of the thermochemical process. It offers some intriguing thermodynamic advantages with direct economic implications. The efficiencies of those cycles make it very likely that at least one of the cycles will be chosen to prove the capability to provide large amounts of hydrogen, e.g. in an industrial demonstration plant [7]. The copperechlorine (CueCl) thermochemical cycle has been identified by Atomic Energy of Canada Limited (AECL) and Argonne National Laboratory as one of the most promising low temperature cycles [8e12]. The CueCl cycle splits

i Qfconv

Qgain Qin

i Qvconv

i Qvrad

Qvsol Qsol R(H2) (s-s0)i t Tia Tamb Tsky Tiv Welec

Convection heat transfer rate between the heat transfer fluid and wall of the absorber pipe in the segment ‘i’, (W) olar heat gained from the PTCs solar field, Watts total heat requirement for the endothermic processes to produce a unit amount of product hydrogen, kJ/mole H2 Convection heat transfer rate between the surface of the envelope to the atmosphere for receiver segment “i”, (W) Radiation heat transfer rate between the outer surface of the envelope to the sky receiver segment “i”, (W) Direct incident solar irradiance absorption rate into the envelope of receiver segment “i”, (W) Direct incident solar irradiance per unit length of receiver, (W/m) the hydrogen production rate, liters (H2)/s molar entropy change of the substance i, kJ/mol.K Time, (s) Absorber pipe temperature in segment ‘i’, (K) Ambient temperature, (K) Estimated effective sky temperature, (K) Glass envelope temperature in segment “i”, (K) electrical work required for the elecrolyzer and the dryer steps, kJ/mole H2

Greek letters HTF density at average temperature of receiver rf segment “i” at Tfi, (kg/m3)

water into hydrogen and oxygen using intermediate copper and chlorine compounds [13,14]. By comparison to other cycles that normally require temperatures above 1100 K, It is a promising cycle because of its relatively low temperature requirement [12]. The CueCl cycle could be linked with thermal solar plant to decompose water into its constituents, oxygen and hydrogen as a net result, using a net input of water and heat. The process involves a series of closed-loop chemical reactions that do not contribute to any greenhouse gas emissions to the environment. The copperechlorine cycle has received increasing attention since 2008. Naterer et al., 2008, have examined the heat requirements of the copperechlorine cycle steps, in efforts to recover as much heat as possible and minimize the net heat supply to the cycle [15]. The electrochemical reaction, copper (Cu) production step, has been described with its operational and environmental conditions, and analyzed thermodynamically by Orhan et al., 2008 [4]. The Results have shown that at a reaction temperature of 45
C and a reference-environment temperature of 25
C, the exergy efficiency of electrochemical reaction has been found to be 99% and to decrease with increasing reference environment and/or reaction temperatures. Haseli et al., 2008, have presented the transport phenomena of a non-catalytic reaction of cupric chloride particles with superheated steam in a fluidized bed for nuclear-based

Please cite this article in press as: Ouagued M, et al., Performance analyses of CueCl hydrogen production integrated solar parabolic trough collector system under Algerian climate, International Journal of Hydrogen Energy (2017), https://doi.org/10.1016/ j.ijhydene.2017.11.040

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 x x x ( 2 0 1 7 ) 1 e1 5

hydrogen production [16]. Numerical results have shown that, the conversion of steam decreases with superficial velocity, whereas the conversion of solid particles increases. The role of the CueCl cycle for thermochemical water decomposition, potentially driven by heat from a nuclear power generation plant, in producing hydrogen in a sustainable way has been investigated by Orhan et al., 2009 [17]. The energy efficiency of the cycle has been found to be 45% and the exergy efficiency 10%. Several variations of copperechlorine cycles with different numbers of steps and methods of grouping have been compared, and major features of the cycles with different numbers of steps have been discussed by Wang et al., 2009 [18,19]. Wang et al. state that the different forms are a result of combining different reaction steps into one reaction [19,20]. The O2 production and the HCl production steps of CueCl cycle have been described by Orhan et al., 2009a, 2009b [21,22]. The operational and environmental conditions of the two reactions were also defined, and a comprehensive thermodynamic analysis was performed. Daggupati et al., 2010 have examined a solid conversion process during hydrolysis and decomposition of cupric chloride [14]. Reaction rate constants and the time required for complete solid conversion are determined by a shrinking-core model. The Results have shown that at a temperature of 375
C, complete conversion of CuCl2 can be achieved by controlling the excess steam, the operating pressure and the inert gas supply. Orhan et al., 2010a, have analyzed a coupling of the CueCl cycle with a desalination plant for hydrogen production from nuclear energy and seawater [23]. Desalination technologies have been reviewed to determine the most appropriate option for the CueCl cycle and a thermodynamic analysis has been presented for various configurations of this coupled system. Exergy-related parameters have also been investigated by Orhan et al., 2010b, to minimize the cost of a CueCl cycle [24]. The Results have shown that the cost rate of exergy destruction varies between 1$ and 15$ per kilogram of hydrogen and the exergy economic factor between 0.5 and 0.02 as the cost of hydrogen rises from 20$ to 140$ per GJ of hydrogen energy. Energy and exergy analyses of the geothermal-based hydrogen production via a new four-step copperechlorine cycle have been conducted by Balta et al., 2010 [25]. As a result, overall energy and exergy efficiencies of the cycle have been found to be 21.67% and 19.35%, respectively, for a reference case. Naterer et al., 2010, have described hydrogen production with Canada's Super-Critical Water Reactor, SCWR [26]. Advances towards an integrated lab-scale CueCl cycle have been discussed, including experimentation, modeling, simulation, advanced materials, thermochemistry, safety, reliability and economics. The impact of exit streams containing by products of incomplete reactions in an integrated thermochemical copperechlorine cycle has been studied by Marin et al., 2011 [27]. They have also examined the implications of incomplete hydrolysis reactions on the kinetics and thermodynamics of the oxygen reactor in the CueCl cycle. Daggupati and al., 2011, have developed a predictive model of convective heat transfer and conversion of cupric chloride particles in a fluidized bed reactor of a copperechlorine cycle [12]. The maximum conversion of steam at 400
C was found to be 3.75% and it requires excess steam of 12.8 mol per unit mole of cupric

3

chloride solid for complete conversion of solid. Orhan et al., 2011, have analyzed several CueCl cycles by examining various design schemes for an overall system and its components, in order to identify potential performance improvements [28]. Rong Xu et al., 2012, have proposed a solar receiver-reactor with integrated energy collection and storage driving the endothermic oxygen production step of the copperechlorine cycle [29]. A pinch methodology has been used by Ghandehariun et al., 2012, to determine the minimum energy requirement for the overall CueCl cycle [30]. Pope et al., 2012, have examined the chemical equilibrium and gaseous product fraction of a multiphase gas-solid flow involving hydrolysis of copper (II) chloride and steam in a packed bed reactor [31]. Ratlamwala et al., 2012, have analyzed an integrated CueCl thermochemical cycle, Kalina cycle and electrolyzer for hydrogen production [32]. The system operating parameters have been varied to investigate their effects on the energy and exergy efficiencies of the integrated system, rate of hydrogen production, and rate of oxygen production. A new photochemical cell has been developed and analyzed for copper disproportionation within the CueCl cycle by Zamfirescu et al., 2012 [33]. The study has examined the feasibility and the expected efficiency of the photochemical disproportionation cell. Simulation models have been developed by Orhan et al., 2012, to analyze, design and optimize the CueCl cycles using the Aspen PlusTM chemical process simulation package [34]. New system configurations for the CueCl cycle have been developed for performance improvement. The Results have shown that the thermal efficiency of the five-step thermochemical process has been 44%, of the four-step process has been 43% and of the three-step process has been 41%, based on the lower heating value of hydrogen. Ratlamwala et al., 2013, have analyzed two integrated systems for hydrogen production, namely: (a) integrated solar heliostat, CueCl cycle and Kalina cycle system and (b) integrated solar heliostat, CueCl cycle, Kalina cycle and electrolyzer system [35]. The results have indicated that system (a) performs better than system (b) from the energy and the exergy perspectives. Thermodynamic analysis of a renewable-based multi-generation energy production system have been developed by Ozturk et al., 2013 [36]. This solarbased multi-generation system consists of four main subsystems: Rankine cycle, organic Rankine cycle, absorption cooling and heating, and hydrogen production and utilization. The solar-based multi-generation system which has an exergy efficiency of 57.35%, is most efficient than using these subsystems separately. Dincer et al., 2013, focuses on a comparative study of five renewable energy based hydrogen production systems namely: (a) CueCl integrated with Kalina cycle, (b) hybrid sulfur (HyS) cycle integrated with isobutane cycle, (c) quintuple flash power plant integrated with electrolyzer, (d) heliostat field integrated with steam cycle, Organic Rankine Cycle (ORC) and electrolyzer, and (d) solar photovoltaic/thermal (PV/T) integrated with triple effect absorption cooling system and electrolyzer [37]. The obtained results shown that system (a) performs the best with energy and exergy efficiencies, sustainability index, and energy demand of the system. Yildiz et al., 2013 have investigated a solarassisted biomass gasification system for hydrogen

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production and assessed its performance thermodynamically using actual literature data [38]. Also, environmental impact of these systems has been evaluated through calculating the specific greenhouse gas (GHG) emissions. Solar energy is considered to be an attractive alternative heat source for hydrogen production that is highly abundant, sustainable and environmentally friendly resource. It can be supplied extensively for large-scale capacities of hydrogen production. It can be used for hydrogen production by using heat from the solar plant for thermochemical processes [39]. Thermochemical “water splitting” requires an intermediate heat exchanger between the solar field and hydrogen plant, which transfers heat from the heat transfer fluid to the thermochemical cycle [40]. Algeria not only has one of the world's most extensive gas reserves, but also has huge renewable energy resources. Fortunately, the geographic location of Algeria has several advantages for the extensive use of solar energy. Located in the Sun Belt region, Algeria has suitable climatic conditions such as the abundant sunshine throughout the year, low humidity and precipitation, water availability, and plenty of unused flat land close to road networks and transmission grids [41]. A lot of work has been done on developing hydrogen production processes coupling with solar energy sources and their application under Algerian climatic conditions. A design of a hydrogen generating station by water vapour electrolysis at high temperatures has been proposed by R. Miri et al., 2007, whose energy resources are solar at several sites of Algeria [42]. The electricity supply is done by photovoltaic cells and the water vapour is ensured by a solar concentrating power station. B. Negrou et al., 2011, have presented numerical simulation of hydrogen generating station by water electrolysis by whose energy resource is solar tower power plant [43]. The hydrogen production rate has been given for various values of the solar radiation and several sites of Algeria. The feasibility of hydrogen production at high temperature electrolyser has been studied by H. Derbal-Mokrane et al., 2011, in Algeria using a hybrid solar resource, parabolic trough concentrators to produce high temperature, steam water and photovoltaic energy for electricity requirements of the HTE [44]. The results have shown that the production rate depends on geographic position, on climatic conditions and on sun radiation. An experimental study of solar hydrogen production system by alkaline water electrolysis in Ouargla (Algeria) city has been presented by N. Chennouf et al., 2012 [45]. The alkaline water electrolysis, with different NaOH concentrations, has been feed by photovoltaic panels. The potential of hydrogen energy production using an electrolyzer-concentrating photovoltaic system has been evaluated by R. Boudries, 2013, for different sites in Algeria [46]. The results have shown that, with the Fresnel reflector, the mean value over the country of the hydrogen production potential is about 0.14 kg H2/m2/day for the least favorable month; while this value is about 0.19 kg H2/ m2/day for the most favorable month. D. Ghribi et al., 2013 have proposed a mathematical model of hydrogen production system, composed of 60 W PV module connected with a commercial 50 W PEM electrolyser equipped with a maximum power point tracking [47]. Comparison of system performance in terms of hydrogen production at seven locations of Algeria

has been given as results. The results have shown that the southern region of Algeria (Adrar, Ghardaia, Bechar and Tamanrasset) is found to have the relatively highest hydrogen production with 20e29 m3/year. Study of the CEVITAL hydrogen production unit has been carried out by R. Boudries et al., 2014 [48]. A PV system for powering the hydrogen production unit has been proposed. The results have shown that the system PV coupled with the hydrogen production unit is viable. A technical and economic analysis for the implementation of a probable molten salt cavity receiver thermal power plant in Algeria has been presented by S. Boudaoud et al., 2015 [49]. The analysis has shown that hybrid molten salt solar tower power technology is very promising in Algeria. A. Saadi et al., 2016 have studied hydrogen production from solar energy available in Biskra region (Algeria) by the Proton Exchange Membrane (PEM) electrolyzer [50]. Experimental performances of three PV generators have been achieved and chosen to feed the PEM electrolyzer. Recently, S. Menia et al., 2017 have proposed methanol electrolysis in order to produce hydrogen [51]. The relation linking hydrogen production rate to the power needed to electrolyse a unit volume of aqueous methanol solution has been determined. Using this relation, the potential of hydrogen from aqueous methanol solution using a PV solar as the energy system has been evaluated for different locations in Algeria. Hydrogen production by methanol electrolysis process (MEP) using PV energy has been investigated by H. Tebibel et al., 2017 [52]. Case studies are carried out on two tilts of PV array: horizontal and tilted at 36
using measured meteorological data of solar irradiation and ambient temperature of Algiers site. Simulation results reveal great opportunities of hydrogen production using MEP with 22.36 g/m2/day and 24.38 g/m2/day of hydrogen when using system with horizontal and tilted PV array position, respectively. The main overall objectives of this research are to propose design for using solar thermal energy within the hydrogen production by thermochemical cycles technique. Based on clear sky model, direct solar radiation has been estimated at different locations representative of different climatic conditions in Algeria. Direct Normal Irradiance is used to estimate the potential for concentrating solar collector for tracking system. The energy performance of the parabolic trough collector is evaluated through a simulation of the successive energy conversions from solar radiation. Thermodynamic analysis accounting for relevant chemical reactions and including the determination of energy and exergy efficiencies is described.

Description of model design The proposed design of the system is shown in Fig. 1. It is integration between a conventional combined CueCl thermochemical cycle for hydrogen production and solar field, based on a parabolic trough solar collector. When solar radiation is available, the solar field starts supplying energy to the thermal cycle from sunrise to sunset. In the integrated system, parabolic trough solar collectors are used to supply the required heat to CueCl thermochemical water splitting. The parabolic trough mirrors are used to reflect the solar light to the receiver. The sun tracking control system drives the solar

Please cite this article in press as: Ouagued M, et al., Performance analyses of CueCl hydrogen production integrated solar parabolic trough collector system under Algerian climate, International Journal of Hydrogen Energy (2017), https://doi.org/10.1016/ j.ijhydene.2017.11.040

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Fig. 1 e Design of the process [53].

collectors to track the sun position. The heat transfer fluid gains a portion of this solar thermal energy by circulating through the absorber receiver by increasing its temperature. This high temperature heat transfer fluid then enters the high temperature heat exchanger where it releases heat to the water returning from CueCl cycle. The super heated steam exiting the high temperature heat exchanger is supplied to the CueCl cycle in order to meet the heat requirement to take the different compounds, used for each reaction of the cycle, to the desired temperatures to produce hydrogen. After releasing heat at different stages in the CueCl cycle, water is supplied back to the high temperature heat exchanger. In this design, the solar field is equipped with tow tank direct storage system. With the storage system, heat gain from the PTC can be stored for later use when the sun sets or is blocked by clouds.

Direct normal solar irradiance To predict thermal performance of parabolic trough collector under Algerian conditions, the climatic and topographical conditions specific to the area have been taken into account by exploiting the direct solar radiation. For concentrating solar collector, the solar designer is only interested in the direct irradiance incident on the aperture. The Direct normal solar irradiance, Iba, the rate at which solar energy is incident on the aperture per unit aperture area, may be calculated from the beam radiation Ibn and the angle of incidence Ɵi using the relation [54e58]: Iba ¼ Ibn$cosðqi Þ

(1)

Ɵi: angle of incidence, (deg), for horizontal tracking axis oriented in North- South, Ɵi is given by:
0;5 qi ¼ cos1 1  ðcosaÞ2 $ðcosAÞ2 with:

(2)

a: solar altitude angle, (deg) A: solar azimuth angle, (deg) Hottel, 1976, has presented a method for estimating the beam radiation Ibn (W/m2) transmitted through clear atmospheres for a standard atmosphere [55,58e60]. Hottel's clearday model of direct normal solar irradiance is based on atmospheric transmittance calculations for four different climate zones in the globe using the 1962 U.S. Standard Atmosphere [61,62]. The beam irradiance is given by: Ibn ¼ I0 $tb

(3)

with: tb: the atmosphere transmittance of beam radiation. I0: the extraterrestrial solar irradiance, outside the earth's atmosphere, W/m2. Using Hottel's clear-day model and applying the appropriate sun angle calculations, we can make hour-by-hour computations of Direct normal irradiance (DNI) incident on the aperture of a collector. The DNI is then summed over the day through application of linear averaging between hours to give the daily direct solar radiation. By integrated the daily direct solar radiation over all the year, we calculate the annual direct normal solar radiation. The tracking system integrated with the collector is one axis tracking system North-South. We select the location of Ghardaia (latitude þ32,48
longitude þ3,66
- Altitude 500 m) from the Algerian territory to represent the first results. Fig. 2 represents the direct normal irradiance on two typical clear days from summer and winter. Fig. 2 shows that the hours of daylight from sunrise to sunset reach 15 h in summer while do not exceed 10 h in winter. We noticed also that in summer for horizontal axis N/S tracking system, the DNI increases from 200 W/m2 at 6 a.m. until 860 W/ m2 at 1 p.m. then starts to decrease to 300 W/m2 at 7 p.m. In winter the DNI rises from 200 W/m2 at 8 a.m. until 440 W/m2 at 2 p.m. and then it descends up to 200 W/m2 at 5 p.m.

Please cite this article in press as: Ouagued M, et al., Performance analyses of CueCl hydrogen production integrated solar parabolic trough collector system under Algerian climate, International Journal of Hydrogen Energy (2017), https://doi.org/10.1016/ j.ijhydene.2017.11.040

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21 Ju ne 21 D ec e m be r Direct solar irradiance per unit of collector area, (W/m2)

10 0 0 800 600 400 200 0 5

10

Tim e (H ours )

15

20

Fig. 2 e Clear-day direct solar irradiance for horizontal axis N/S tracking system configurations for Ghardaia.

To compare the importance of direct solar radiation in different sites, we report in Table 2, the annual direct normal solar radiation for a North/South one axis tracking system at six typical locations in Algeria namely, Algiers, Annaba, Oran,
char, Ghardaia and Tamanrasset. In Table 1, the Be geographical positions and the type of climate for each location are reported. The results reveal that the most important DNI potential is found in the Sahara for Ghardaia with 2.516 MWh/m2/year,
char with 2.7 MWh/m2/year and the best in Tamanrasset Be with 3.111 MWh/m2/year. Knowing that concentrating solar power systems are economic only for locations with DNI above 1800 kWh/m2/year with an average daily DNI above 5 kWh/m2/day, prove that Algerian solar radiation is more than sufficient for the solar thermal exploitation of solar energy. This is more particularly true in the south.

Heat gain by parabolic trough collectors We consider in this study a number of 100 Solar Collector Assembly (SCA) with 7.8 m in length divided on a loops of 20 SCAs to demonstrate the PTC performance under Algerian conditions. The proposed plant is presented in Fig. 3. The chosen collector is of LS-2 type with vacuum in the annulus space between the absorber and the glass envelope. The heat transfer model is based on an energy balance between the fluid and the surroundings as presented by Ouagued et al., 2012, 2013 [63,64] (see Fig.4). The global HTF heat gained per unit length of the receiver Qgain (W/m) is given by:

Table 2 e Annual direct normal solar radiation for a North/South one axis tracking system for different locations in Algeria. Algerian Location

Annual Direct Normal solar Irradiance (MWh/m2/year)

Oran Algiers Annaba Ghardaia Bechar Tamanrasset

Qgain ¼

2.229 2.158 2.159 2.516 2.7 3.111


Ff $rf $Cf $ Tout  Tin f f

(4)

L

with: Tout f : The HTF temperature at the output of the receiver, (K) Tin f : The HTF temperature at the input of the receiver, (K) Syltherm 800 HTF temperature profile, heat gain from PTC and thermal efficiency have been estimated for two typical days of summer and winter in the daylight period in clear sky in the location of Ghardaia. The tracking system integrated with the PTC is one axis tracking system North-South. Results are presented in Figs. 5e7. Fig. 5 presents the variation of the outlet temperatures of the Syltherm 800 HTF as function of time for typical days of the year (summer and winter) with one axis tracking system North-South. According to the results, the maximum

Table 1 e Latitude angle, longitude angle, altitude from mean sea level, and climate type for different locations. Climate type Mid latitude summer Mid latitude summer Mid latitude summer Tropical Tropical Tropical

Altitude (km)

Longitude (deg)

Latitude (deg)

Location

0,025 0,040 0,099 0,806 0,500 1378

3,15 7,8 0,37 2,15 3,66 5,31

36,43 36,8 35,38 31,38 32,48 22,47

Algiers Annaba Oran Bechar Ghardaia Tamanrasset

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1 SCA (Solar Collector Assembly)

A Loop of 20 SCA

Cu-Cl THERMOCHEMIC AL

78 m

Hot Cold STORAGE SYSTEM

Fig. 3 e Solar field layout for the proposed plant [53]. temperature of Syltherm 800 is reached in the typical summer day, Syltherm 800 temperature exceeds 700 K between 1 p.m. and 4 p.m. Furthermore, it reaches only 600 K in the typical winter day. We observe also from Figs. 6 and 7 that the heat gain and thermal efficiency follow the temperature profile of the syltherm 800. Figures prove also that heat gain provided by PTC is important in typical summer day with heat gain and thermal efficiency exceed 3000 W/m and 70%, respectively. In typical winter day, the heat gain and thermal efficiency provided by PTC exceed 1600 W/m and 48%, respectively. The heat gain is influenced by the climatic conditions of each site like the DNI, the ambient temperature and the wind speed.

21 June 21 December

Fig. 4 e Heat transfer plant for a solar PTC [63].

3500

Heat Gain (W/m)

750 Syltherm 800 Temperature (K)

3000

21 June 21 December

700 650 600 550

2500 2000 1500 1000 500

500

0

450 8

10

12

14 Time (Hour)

16

18

Fig. 5 e Outlet Syltherm 800 temperature for Ghardaia.

20

7

8

9 10 11 12 13 14 15 16 17 18 19 20 Time (Hours)

Fig. 6 e Global heat gain form PTC system in Ghardaia, (W/m).

Please cite this article in press as: Ouagued M, et al., Performance analyses of CueCl hydrogen production integrated solar parabolic trough collector system under Algerian climate, International Journal of Hydrogen Energy (2017), https://doi.org/10.1016/ j.ijhydene.2017.11.040

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21 June 21 December

Table 3 e Annual Heat Gain by one axis N/S tracking system of PTC for different locations in Algeria.

80

Algerian Location

Efficiency (%)

70 60

Annual Heat Gain by PTC System (MWh/m/year)

Oran Algiers Annaba Ghardaia Bechar Tamanrasset

50 40 30 20

8.73 8.56 8,56 9,33 9,61 10,28

10 0

7

8

9 10 11 12 13 14 15 16 17 18 19 20 Time (Hours)

Fig. 7 e Thermal efficiency form PTC system in Ghardaia.

The monthly mean daily global heat gain is determined for six Algerian locations in Fig. 8. The results are given for PTC system with one axis tracking system oriented to the North/ South direction using Syltherm 800 as heat transfer fluid. It is noticed in Fig. 8 that the summer season has the most important monthly mean daily heat gain in the six selected sites. In addition, we note that the monthly mean daily heat gain in summer is about 120e130 MJ/m/day for all the studied regions. This is due to the warm climate of the entire Algerian territory in this period. In winter, a difference can be seen from the North to the South with an average of 35e60 MJ/m/ day in the north (Oran, Algiers and Annaba), an average of 50e70 MJ/m/day in Bechar and Ghardaia and more than 70 MJ/ m/day in Tamanrasset. In Table 3, the annual heat gain by one axis N/S tracking system of PTC was estimated and presented for the six Algerian locations.

Thermodynamic analysis of CueCl thermochemical cycle for hydrogen production The CueCl cycle splits water into hydrogen and oxygen through intermediate copper and chlorine compounds. The

CueCl cycle in this system is developed in the Clean Energy Research Laboratory (CERL) at the UOIT [34]. It is a hybrid process using heat essentially and some electricity to split water to produce hydrogen. The setup is based on the fourstep CueCl cycle given by Orhan et al., 2012, in Fig. 9 [34]. The CueCl cycle is divided into four steps, namely: 400
C

ðaÞHydrolysis:H2 0ðgÞ þ 2CuCl2 ðsÞ þ QI !CuOCuCl2 ðsÞ þ 2HClðgÞ

(5)

1 500
C ðbÞOxygen production:CuOCuCl2 ðsÞ þ QII !2CuClðlÞ þ O2 ðgÞ 2 (6) 80
C

ðcÞDrying:CuCl2 ðaqÞ!CuCl2 ðsÞ þ H2 OðgÞ

(7) 25
C

ðdÞHydrogen production:2HClðaqÞ þ 2CuClðaqÞ!2CuCl2 ðaqÞ þ H2 ðgÞ (8)

Energy and exergy study of the CueCl cycle To evaluate the energy required by the copperechlorine cycle, a thermodynamic analysis will be performed to determine the heat released or absorbed by each step of the CueCl cycle [15]. All quantities are provided per mole of hydrogen produced. Also, we assume that [4,21,22,25]:

O ra n

G h a rd a ia

A lg ie rs Annaba

B echar T a m n ra s s e t

Monthly mean daily global heat gain (MJ/m/day)

140 120 100 80 60 40 20 0

1

2

3

4

5

6 7 M o n th

8

9

10

11

12

Fig. 8 e Monthly mean daily global heat gain of syltherm 800 for different locations. Please cite this article in press as: Ouagued M, et al., Performance analyses of CueCl hydrogen production integrated solar parabolic trough collector system under Algerian climate, International Journal of Hydrogen Energy (2017), https://doi.org/10.1016/ j.ijhydene.2017.11.040

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 x x x ( 2 0 1 7 ) 1 e1 5

9

Fig. 9 e Thermochemical CueCl Cycle [32,34].

 The reference environment temperature (T0) and pressure (P0) are 298.15 K and 1 atm, respectively.  The chemical reaction reactants and products are at the reaction temperature and a pressure of 1 atm.  The process occurs at steady state and steady-flow with negligible potential and kinetic energy changes.  The heat exchanger effectiveness is assumed to be 100%, based on the study conducted by Dincer et al., 2007 [65].

Study of hydrolysis step (HCl production), TI ¼ 400
C The heat transfer for a chemical process is determined from the energy balance applied to the system for a steady-state reaction process [17,22,28,66]:

QI ¼ DHI ðTI Þ ¼ DH+I ðT0 Þ þ nCuOCuCl2 $ ðh  h0 ÞCuOCuCl2 þ nHCl $ ðh  h0 ÞHCl  nH2O $ ðh  h0 ÞH2O  nCuCl2 $ðh  h0 ÞCuCl2

(9)

The exergy balance for a chemical reactions for a steadystate process can be written as [4,21,22,25,38]: ExdesI ¼ nCuCl2 $exðCuCl2Þ þ nH2O $exðH20Þ  nCuOCuCl2 $exðCuOCuCl2Þ   T0 $QI  nHCl $exðHClÞ þ 1  TI (10) The specific molar exergy ex, (kJ/mol), of a flow can be expressed as [4,21,22,25,67]:

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  exi ¼ ðh  h0 Þ  T0 $ ðs  s0 Þ þ exch i

(11)

Then, the exergy balance become:   ExdesI ¼ nCuCl2 $ ðh  h0 Þ  T0$ðs  s0 Þ þ exch CuCl2   þ nH2O $ ðh  h0 Þ  T0$ðs  s0 Þ þ exch H2O    nCuOCuCl2 $ ðh  h0 Þ  T0$ðs  s0 Þ þ exch CuOCuCl2     T0 $QI  nHCl $ ðh  h0 Þ  T0$ðs  s0 Þ þ exch HCl þ 1  TI (12)

Study of O2 production step (TII ¼ 500
C) Similar to Eq. (9), the steady-state heat rate balance for the O2 production step can be expressed as follows [17,22,28,31,66]: QII ¼ DHrðTII Þ ¼ DHrðT0 Þ þ nCuCl $ ðh  h0 ÞCuCl þ nO2 $ ðh  h0 ÞO2

 nCuOCuCl2 $ h0  h00 CuOCuCl2

(13)

Similar to Eq. (10), the steady-state exergy rate balance for the O2 production step can be reduced to [4,21,22,25]: ExdesII ¼ nCuCl2 $ ex0 ðCuOCuCl2Þ  nO2 $ exðO2 Þ  nCuCl $ exðCuClÞ   T0 $ QII þ 1 TII (14) Using the specific exergy of a flow, the exergy balance for the O2 production step become: ExdesII

  ¼ nCuOCuCl2 $ ðh  h0 Þ  T0$ðs  s0 Þ þ exch CuOCuCl2    nO2 $ ðh  h0 Þ  T0$ðs  s0 Þ þ exch O2     T0 $QII  nCuCl $ ðh  h0 Þ  T0$ðs  s0 Þ þ exch CuCl þ 1  TI (15)

Parameters of the equations steps After writing mass, energy and exergy balances for the chemical reactions, enthalpy change of reaction in standard conditions, enthalpy and entropy change of each compound are evaluated here. The enthalpy change of reactions at standard conditions DH+r ðT0 Þ is given by Hess Equation: DH+r ðT0 Þ ¼

X

ni $ DH+f ðiÞproduct 

X

ni $ DH+f ðiÞreactant

(16)

The enthalpy change and the entropy change of a substance that is cooled or heated over a particular temperature range can be calculated as [4,21,22,25,27,29,31,66]: ZTf ðh  h0 Þi ¼

Cpi $ dT

(17)

dT T

(18)

Ti

ZTf ðs  s0 Þi ¼

Cpi $ Ti

where Cpi (J/mol.K) is the molar specific heat of the substance and the subscripts on Ti and Tf are the initial and final temperatures, respectively. The equations above cannot be directly applied to substances with phase change. The enthalpy change caused by

the phase must be added to the value calculated to obtain the total enthalpy and entropy change for those substances. The specific heat of the substances is found from the following correlations in Table 4, with t is 1/1000 of the specified temperature (in K) of a compound, i.e., t ¼ T(K)/1000 [29,30]:

Study of heat exchangers In order to produce hydrogen from the process, eight heat exchangers are needed to take the different compounds, used for each reaction of the cycle, to the desired temperatures: four exchangers for heating the compounds and four exchangers for cooling the compounds as follow: Heating exchangers HE1 : H2OðlÞat T0/H2OðgÞat TI HE2 : CuCl2ðsÞat TIII/CuCl2ðsÞat TI HE3 : CuOCuCl2ðsÞat TI/CuOuCl2ðsÞat TII HE5 : CuCl2ðaqÞat TIV/CuCl2ðaqÞat TIII

(19)

Cooling exchangers HE4 : HClðgÞat TI/HClðgÞat TIV HE6 : H2OðlÞat TIII/H2OðlÞat TIV HE7 : CuClðlÞat TII/CuClðlÞat TIV HE8 : O2ðgÞat TII/O2ðgÞat T0

(20)

The heat of a substance that is cooled or heated in a heat exchanger over a particular temperature range can be calculated as follow [15,23,24,29,30,66]: 2 6 QHEi ¼ ni 4

ZTf

3 7 Cpi $dT5

(21)

Ti

where QHEi (kJ/mol H2) is the heat in each exchanger. The equations above cannot be directly applied to substances with phase change. The enthalpy change caused by the phase must be added to the value calculated to obtain the total enthalpy for those substances. The thermal exergy ExHEic (kJ/mol H2) in each heat exchanger is defined from the heat in each exchanger as [32,35,37,38]: ExHEi ¼

  T0 $QHEi 1 Ti

(22)

where QHEi is positive for heating exchangers and negative for cooling exchangers.

Energy and exergy efficiency There has been much debate as to whether the higher heating value (HHV) or lower heating value (LHV) of hydrogen should be used in efficiency calculations. The HHV of 286 kJ/ mol is the absolute value of standard enthalpy of the formation of liquid water at 298.15 K. The LHV of 241.83 kJ/mol is the absolute value of standard enthalpy of the formation of water vapor at 298.15 K and 1 atm [9e11,33,66,68]. The energy efficiency of the process is defined as energy out divided by energy in. Based on the HHV for hydrogen, the efficiency of this process is given by: henergy ¼

HHVðH2Þ Qin þ Welec

(23)

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Table 4 e Specific heat for chemical compounds. Cpi (J/mol/K)

Correlation

CuOCuCl2ðsÞ CuCl2ðsÞ

99:23243 þ 21:62162$t 70:21882 þ 23:36132$ t  14:86876$ t2  þ4:053899$ t3  0:366203 t2

H2OðlÞ

203:606 þ 1523:29$t  3196:413$t2

H2OðgÞ

30:092 þ 6:832514$t  6:793435$t2  2:53448$t3  þ0:082139 t2

HClðgÞ

32:12392  13:45805$t þ 19:86852$t2  6:853936$t3  0:049672 t2

CuClðsÞ

75:271  26:83212$t þ 25:69156$t2  7:357982$t3  1:847747 t2

CuClðlÞ

66:944  3:699628:1010 $t þ 2:166748:1010 $t2  3:90046:1011 $t3  9:813196:1012 t2

O2 ½100K  700K

31:32234  20:2353$t

O2 ½700K  2000K

330:03235 þ 8:772972$t  3:988133$t2  þ0:788313$t3  0:741599 t2

 þ2474:544$ t3 þ 3:855326 t2

 þ57:86644$t2  36:50624$t3  0:007374 t2

where: Welec: is the electrical work required for the elecrolyzer and the dryer steps. Qin: is the total heat requirement for the endothermic processes to produce a unit amount of product hydrogen, kJ/ mole H2. An exergy efficiency can be formulated for the reacting system. At steady state, the rate at which exergy enters the reacting system equals to the rate at which exergy exits plus the rate at which exergy is destroyed within the system. We assume the reactor is well insulated, so there is no heat transfer and thus no accompanying exergy transfer. An exergy efficiency can be written as [23e25]: hexergy ¼

ExH2 Exin þ Exelec

(24)

Table 5 e Standard enthalpy of formation and standard chemical exergy for chemical compounds.


Compound

DH f (kJ/mole)

CuCl2(s) CuOCuCl2(s) HCl(g) H2O(g) CuCl(l) O2(g) H2(g)

205.83 384.65 92.312 241.82 136.82 0 0

ex

ch

(kJ/mole)

82.47 21.08 84.531 9.437 75 3.97 235.15

Where Exin, (kJ/mole H2), is the exergy input to the process that enters with the reactants plus heat, and ExH2, (kJ/mole H2), is the exergy content of hydrogen, as well as Exelec, (kJ/ mole H2), is the exergy associated with electricity work. The exergy content of hydrogen is given as [32]:

ExðH2Þ ¼ exch ðH2Þ þ DHðH2Þ  T0$ DSðH2Þ

(25)

With (Heintz, 2012, Lewis et al., 2009): DHðH2Þ ¼ HHV ¼ 286

DSðH2Þ ¼ 44:33

kJ mole

J mole$K

The standard enthalpy of formation and standard chemical exergies at 298.15 K and 1 atm of all compounds involved in the CueCl cycle are given in Table 5 [17,25]:

Results and discussions Using the thermodynamic methods detailed in the previous sections and specifying the operating conditions from experimental data in literature, the CueCl cycle has been simulated. The model calculates the heat of reactions at the specified conditions. The total heat requirement for the endothermic processes is 619.3 kJ/mol and heat recovery from the exothermic processes is 113.42 kJ per mol of hydrogen. For

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electrolysis and dryer steps, the electrical energy requirement is given by Orhan et al., 2012, as 88.2 kJ/mol H2 [34].  Without the recovered heat within the cycle again (all the heat rejected by the system is dumped into the atmosphere), the energy efficiency of the system is found to be 40.42% as compared to 40.04% reported by Orhan et al., 2012 [34], and 52% reported by Ratlamwala et al., 2012 [32]: henergy ¼

286 ¼ 40:42% 619:3 þ 88:2

 Using the recovered heat within the cycle again, all of the waste heat is recycled backed and is utilized for endothermic processes, the energy efficiency of the system is found to be 48.14%: henergy ¼

286 ¼ 48:14% 619:3  113:42 þ 88:2

 The total exergy requirement for the processes is 464.761 kJ/mol. The predicted exergy efficiency of the system is found to be 92.25% as compared to 82.91% reported by Ratlamwala et al., 2012 [32]: hexergy ¼

507:94 ¼ 92:25% 464:761 þ 88:2

Based on results given above, the capacity of the cycle combined with a PTC in the Algerian condition is evaluated. Since Algeria has favorable climatic conditions for the construction of parabolic trough solar thermal power plants as presented in the previous parts. The monthly mean heat gain by parabolic trough power plant has been estimated for six locations selected from the Algerian territory. The hydrogen production rate is calculated from: RðH2 Þ ¼

Qgain MðH2Þ $ Qin rðH2Þ

(26)

The daily hydrogen production rate is calculated from the CueCl cycle combined with a solar parabolic trough power plant, as follows: " Rday ðH2 Þ ¼ h$

SX 0 1

# 2

RðH2 Þ $MðH2 Þ

(27)

i¼1

where Rday(H2), in Tons(H2)/day, is the daily hydrogen production rate, h (one hour or 3600 s), is the integration step. S0, is the hours of daylight. In an integrated solar system, studying the effect of fluctuation in heat gain from this system on the performance of the overall system is very important as heat gain is not constant throughout the day. The rate of hydrogen production by the combined CueCl cycle in the daylight period of two typical days of winter and summer is presented in Fig. 10. It is observed from Fig. 10 that, for typical summer day, the rate of hydrogen produced by the system increases from 15 l/s in the morning to 96.8 l/s around 3 p.m., then starts to decrease to the end of the daylight period. In the typical winter day, same remark was observed, the rate of hydrogen produced by the system increases to 50 l/s around 2 p.m., then starts to decrease to the end of the daylight period. It is noticed

Fig. 10 e Hydrogen production rate in Ghardaia, (l/s). form Fig. 6 that the profile of the hydrogen production rate corresponding to that of the heat gain from the solar field. Such behavior is observed because the increases of the global heat gain is proportional to the increase of fluid temperature used in the absorber of the parabolic trough collector. Syltherm 800 absorbs heat from the solar receiver due to its capabilities of catering large temperature ranges. With increase in the rate of heat transfer by the syltherm 800 coming from the solar receiver, the amount of heat supplied to the CueCl cycle increases. Results show that, integrating over all the day, hydrogen production is about 0.20 kg/m2/day in typical day of winter compared to 0.14 kg/m2/day and 0.10 kg/m2/day given by R. Boudries, 2013, using an electrolyzer-concentrating photovoltaic system with Fresnel reflector and parabolic trough reflector, respectively [46]. In typical day of summer, we find about 0.47 kg/m2/day compared to 0.19 kg/m2/day and 0.17 kg/ m2/day using an electrolyzer-CPV technology with Fresnel reflector and parabolic trough reflector, respectively [46]. To compare hydrogen production in different sites, we present in Fig. 11 the monthly hydrogen production for the six Algerian locations. Fig. 11 reveals that the heat collected from the PTC affects the hydrogen production rate from the CueCl cycle. On the other hand, since the monthly heat gain is influenced by the climatic conditions of each site, the hydrogen production is also influenced by the location. We observe from Fig. 11 that the hydrogen production is most important in the South of Algeria for Ghardaia, Bechar and Tamanrasset overall the year which is due to the important heat gain from PTC due to the increasing direct solar radiation in the south of the country. In addition, the maximum hydrogen production is observed in the summer season which occurs in June with about 10 Ton H2. In winter, a difference can be seen from the North to the South with an average of 2.8e5 Ton H2 in the north (Oran, Algiers and Annaba), an average of 4e7 Ton H2 in Bechar and Ghardaia and more than 5.5 Ton H2 in Tamanrasset. The results show that for Algiers site, the mean daily production of hydrogen is estimated to be around 0.28 kg/m2/day compared to 22.36.103 kg/m2/day and 24.38.103 kg/m2/day given by H. Tebibel et al., 2017, when using methanol electrolysis system with horizontal and tilted PV array position, respectively [52].

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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 x x x ( 2 0 1 7 ) 1 e1 5

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Fig. 11 e Monthly production of Hydrogen, (Ton H2).

Table 6 e Annual hydrogen production for different locations in Algeria. Algerian Location Oran Algiers Annaba Ghardaia Bechar Tamanrasset

Annual Hydrogen Production (Ton H2/ year) 79,40 77.90 77.86 84.87 87.44 93.55

In Table 6, the annual hydrogen production was estimated and presented for the six Algerian locations.

Conclusion The study consists of a solar model for the direct solar radiation, a dynamic model for the collector field and a steady-state model for CueCl thermochemical cycle. The solar model, the collector field model and the CueCl cycle for hydrogen production model were combined to an entire plant model that was evaluated under Algerian conditions. For the solar field, a model, based on the clear sky, has been used to estimate the direct solar radiation for a system equipped with one axis tracking system oriented to the North/South at different locations representative of different climatic conditions in Algeria. The important DNI potential is found in the Sahara for
char with 2.7 MWh/m2/ Ghardaia with 2.52 MWh/m2/year, Be year and the best in Tamanrasset with 3.11 MJ/m2/year. For the collector field, a thermal model was used to predict thermal performance of parabolic trough collectors under Algerian conditions. The annual heat gain by one axis N/S tracking PTC system is found in the Sahara for Ghardaia about
char about 9.61 MWh/m/year and the 9.33 MWh/m/year, Be best in Tamanrasset with about 10.28 MWh/m/year. A thermodynamic analysis has been developed for relevant chemical reactions and including the determination of energy and exergy efficiencies of CueCl cycle. The overall energy and

exergy efficiencies of the CueCl cycle are obtained as 40.42% and 92.25%, respectively, based upon the reference conditions. A parametric study is conducted to investigate the effects of several operating parameters such as heat gain from the solar PTC on the rate of hydrogen produced. A comparative assessment is carried out to study the effect of different Algerian locations and climates on hydrogen production rate from CueCl. These analyses have revealed that the rate of hydrogen production by the CueCl cycle is proportional to the heat gain from the solar PTC. In addition, the maximum annually hydrogen production is obtained for the Southern Algerian regions, for Ghardaia, Bechar and Tamanrasset with 84.87 Ton H2, 87.44 Ton H2 and 93.55 Ton H2, respectively. For the Northern Algerian regions, the best hydrogen production is observed for the Western site with 79.4 Ton H2 for Oran. Simulation results reveal great opportunities of hydrogen production using CueCl cycle combined with solar PTC compared to other systems studied in the same climatic conditions. In this regard, it is better to use solar energy through hybrid or thermochemical cycles for sustainable hydrogen production which appears to be an eco-friendly and sustainable option for the countries having abundant solar energy resources as Algeria. The main energy input needed by such systems is high temperature heat. However, some electricity is still needed to transport materials, operate pumps, compressors, electrochemical reaction, and so forth. In all cases, the electricity represents a small fraction of the total energy input inventory.

references

[1] Boudries R, Dizene R, Khellaf AM, Belhamel M. Hydrogen as an energy carrier. In: Harris Aiden M, editor. Clean energy: resources, production and developments. Nova Science Publishers, Inc.; 2012. p. 147e84. [2] Balat M. Potential importance of hydrogen as a future solution to environmental and transportation problems. Int J Hydrogen 2008;33:4013e29. [3] Ponomarev-Stepnoi NN. Nuclear-hydrogen power. At Energy 2004;96:375e85.

Please cite this article in press as: Ouagued M, et al., Performance analyses of CueCl hydrogen production integrated solar parabolic trough collector system under Algerian climate, International Journal of Hydrogen Energy (2017), https://doi.org/10.1016/ j.ijhydene.2017.11.040

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[4] Orhan MF, Dincer I, Rosen MA. Thermodynamic analysis of the copper production step in a copperechlorine cycle for hydrogen production. Thermochim Acta 2008;480:22e9. [5] Funk JE. Thermochemical hydrogen production: past and present. Int J Hydrogen Energy 2001;26(3):185e90. [6] Dincer I, Balta MT. Potential thermochemical and hybrid cycles for nuclear-based hydrogen production. Int J Energy Res 2011;35:123e37. [7] Sattler C, Roeb M, Agrafiotis C, Thomey D. Solar hydrogen production via sulphur based thermochemical watersplitting. Solar Energy 2017. article in press. [8] Serban M, Lewis M, Basco J. Kinetic study of the hydrogen and oxygen production reactions in the copper-chloride thermochemical cycle. New Orleans, LA: AIChE Spring National Meeting; April 2004. p. 25e9. [9] Naterer GF, Suppiah S, Lewis M, Gabrie KS, Dincer I, Rosen MA, et al. Recent Canadian advances in nuclear-based hydrogen production and the thermochemical Cu-Cl cycle. Int J Hydrogen Energy 2009;34:2901e17. [10] Lewis MA, Ferrandon MS, Tatterson DF, Mathias P. Evaluation of alternative thermochemical cycles-part III. Further development of the Cu-Cl cycle. Int J Hydrogen Energy 2009a;34:4136e45. [11] Lewis MA, Masin JG. The evaluation of alternative thermochemical cycles-part II. The down selection process. Int J Hydrogen Energy 2009b;34:4125e35. [12] Daggupati VN, Naterer GF, Dincer I. Convective heat transfer and solid conversion of reacting particles in a copper (II) chloride fluidized bed. Chem Eng Sci 2011;66:460e8. [13] Lewis MA, Serban M, Basco JK. Hydrogen production at <550
C using a low temperature thermochemical cycle. New Orleans: ANS/ENS Exposition; November 2003. [14] Daggupati VN, Naterer GF, Gabriel KS. Diffusion of gaseous products through a particle surface layer in a fluidized bed reactor. Int J Heat Mass Transf 2010;53:2449e58. [15] Naterer GF, Gabriel K, Wang ZL, Daggupati VN, Gravelsins R. Thermochemical hydrogen production with a copperechlorine cycle. I: oxygen release from copper oxychloride decomposition. Int J Hydrogen Energy 2008;33:5439e50. [16] Haseli Y, Dincer I, Naterer GF. Hydrodynamic gasesolid model of cupric chloride particles reacting with superheated steam for thermochemical hydrogen production. Chem Eng Sci 2008;63:4596e604. [17] Orhan MF, Dincer I, Rosen MA. Efficiency analysis of a hybrid copperechlorine (CueCl) cycle for nuclear-based hydrogen production. Chem Eng J 2009;155:132e7. [18] Ghandehariun S. Thermal management of the copperchlorine cycle for hydrogen production: analytical and experimental investigation of heat recovery from molten salt. Doctoral thesis. Canada: University of Ontario Institute of Technology; 2012. [19] Wang ZL, Naterer GF, Gabriel KS, Gravelsins R, Daggupati VN. Comparison of different copper-chlorine cycles for hydrogen production. Int J Hydrogen Energy 2009;34:3267e76. [20] Mapamba LS. Simulation of the copper-chlorine thermochemical cycle. Master thesis. South Africa: Noordwes-Universiteit Potchefstroomkampus; 2011. [21] Orhan MF, Dincer I, Rosen MA. The oxygen production step of a copperechlorine thermochemical water decomposition cycle for hydrogen production: energy and exergy analyses. Chem Eng Sci 2009a;64:860e9. [22] Orhan MF, Dincer I, Rosen MA. Energy and exergy analyses of the fluidized bed of a copperechlorine cycle for nuclearbased hydrogen production via thermochemical water decomposition. Chem Eng Res Des 2009b;87:684e94. [23] Orhan MF, Dincer I, Naterer GF, Rosen MA. Coupling of copper-chloride hybrid thermochemical water splitting cycle

[24]

[25]

[26]

[27]

[28]

[29]

[30]

[31]

[32]

[33]

[34]

[35]

[36]

[37]

[38]

[39]

[40] [41]

[42] [43]

with a desalination plant for hydrogen production from nuclear energy. Int J Hydrogen Energy 2010a;35:1560e74. Orhan MF, Dincer I, Rosen MA. Exergoeconomic analysis of a thermochemical copperechlorine cycle for hydrogen production using specific exergy cost (SPECO) method. Thermochim Acta 2010b;497:60e6. Balta MT, Dincer I, Hepbasli A. Energy and exergy analyses of a new four-step copper-chlorine cycle for geothermal-based hydrogen production. Energy 2010;35:3263e72. Naterer GF, Suppiah S, Stolberg L, Lewis M, Wang Z, Daggupati V, et al. Canada's program on nuclear hydrogen production and the thermochemical Cu-Cl cycle. Int J Hydrogen Energy 2010;35:10905e26. Marin GD, Wang Z, Naterer GF, Gabriel K. Byproducts and reaction pathways for integration of the Cu-Cl cycle of hydrogen production. Int J Hydrogen Energy 2011;36:13414e24. Orhan MF, Dincer I, Rosen MA. Design of systems for hydrogen production based on the Cu-Cl thermochemical water decomposition cycle: configurations and performance. Int J Hydrogen Energy 2011;36:11309e20. Xu R, Wiesner TF. Dynamic model of a solar thermochemical water-splitting reactor with integrated energy collection and storage. Int J Hydrogen Energy 2012;37:2210e23. Ghandehariun S, Rosen MA, Naterer GF, Wang Z. Pinch analysis for recycling thermal energy in the Cu-Cl cycle. Int J Hydrogen Energy 2012;37:16535e41. Pope K, Wang ZL, Naterer GF, Secnik E. Interfacial thermodynamics and X-ray diffraction of hydrolysis products in multiphase reacting flow of the Cu-Cl cycle. Int J Hydrogen Energy 2012;37:15011e9. Ratlamwala TAH, Dincer I. Energy and exergy analyses of a CueCl cycle based integrated system for hydrogen production. Chem Eng Sci 2012;84:564e73. Zamfirescu C, Naterer GF, Dincer I. Photo-electro-chemical chlorination of cuprous chloride with hydrochloric acid for hydrogen production. Int J Hydrogen Energy 2012;37:9529e36. Orhan MF, Dinc¸er I, Rosen MA. Efficiency comparison of various design schemes for copperechlorine (Cu-Cl) hydrogen production processes using Aspen Plus software. Energy Convers Manag 2012;63:70e86. Ratlamwala TAH, Dincer I. Performance assessment of solarbased integrated CueCl systems for hydrogen production. Solar Energy 2013;95:345e56. Ozturk M, Dincer I. Thermodynamic analysis of a solar-based multi-generation system with hydrogen production. Appl Therm Eng 2013;51:1235e44. Dincer I, Ratlamwala TAH. Development of novel renewable energy based hydrogen production systems: a comparative study. Energy Convers Manag 2013;72:77e87. Kalinci Y, Hepbasli A, Dincer I. Performance assessment of hydrogen production from a solar-assisted biomass gasification system. Int J Hydrogen Energy 2013;38:6120e9. Haseli Y. Analysis of hydrodynamic transport phenomena in a fluidized bed for thermochemical hydrogen production. Master thesis. Canada: University of Ontario Institute of Technology; 2008. Forsberg CW. Hydrogen, nuclear energy, and the advanced nuclear reactor. Int J Hydrogen Energy 2003;28:1073e81. Boukelia TE, Mecibah MS. Parabolic trough solar thermal power plant: potential, and projects development in Algeria. Renew Sustain Energy Rev 2013;21:288e97. Miri R, Mraoui S. Electrolyte process of hydrogen production by solar energy. Desalination 2007;206:1e3. 69-775. Negrou B, Settou N, Chennouf N, Dokkar B. Valuation and development of the solar hydrogen production. Int J Hydrogen Energy 2011;36(6):4110e6.

Please cite this article in press as: Ouagued M, et al., Performance analyses of CueCl hydrogen production integrated solar parabolic trough collector system under Algerian climate, International Journal of Hydrogen Energy (2017), https://doi.org/10.1016/ j.ijhydene.2017.11.040

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[44] Derbal-Mokrane H, Benzaoui A, M'Raoui A, Belhamel M. Feasibility study for hydrogen production using hybrid solar power in Algeria. Int J Hydrogen Energy 2011;36(6):4198e207. [45] Chennouf N, Settou N, Negrou B, Bouziane K, Dokkar B. Experimental study of solar hydrogen production performance by water electrolysis in the south of Algeria. Energy Proc 2012;18:1280e8. [46] Boudries R. Analysis of solar hydrogen production in Algeria: case of an electrolyzer- CPV system. Int J Hydrogen Energy 2013;38:11507e18. [47] Ghribi D, Khelifa A, Diaf S, Belhamel M. Study of hydrogen production system by using PV solar energy and PEM electrolyser in Algeria. Int J Hydrogen Energy 2013;38(20):8480e90. [48] Boudries R, Khellaf A, Aliane A, Ihaddaden L, Khida F. PV system design for powering an industrial unit for hydrogen production. Int J Hydrogen 2014;39:15188e95. [49] Boudaoud S, Khellaf A, Mohammedi K, Behar O. Thermal performance prediction and sensitivity analysis for future deployment of molten salt cavity receiver solar power plants in Algeria. Energy Convers Manag 2015;89:655e64. [50] Saadi A, Becherif M, Ramadan HS. Hydrogen production horizon using solar energy in Biskra, Algeria. Int J Hydrogen Energy 2016;41(47):21899e912. [51] Menia S, Lassouane F, Tebibel H, Khellaf A, Nouicer I. Hydrogen production by methanol aqueous electrolysis using photovoltaic energy: Algerian potential. Int J Hydrogen Energy 2017;42:8661e9. [52] Tebibel H, Khellaf A, Menia S, Nouicer I. Design, modeling and optimal power and hydrogen management strategy of an off grid PV system for hydrogen production using methanol electrolysis. Int J Hydrogen Energy 2017;42(22):14950e67. [53] Ouagued M, Khellaf A, Loukarfi L. Hydrogen production by thermal solar system: application in Algeria. LAP Lambert Academic Publishing; 2015. [54] Bialobrzeski RW. Optimization of a SEGS solar field for cost effective power output. Master thesis of Science in Mechanical Engineering, Georgia Institute of Technology. 2007. [55] Duffie JA, Beckman WA. Solar engineering Transmittance of thermal processes. second ed. Madison: John Wiley &Sons, Inc; 1991. [56] Notton G, Poggi P, Cristofari C. Predicting hourly solar irradiations on inclined surfaces based on the horizontal

[57]

[58]

[59]

[60]

[61] [62]

[63]

[64]

[65] [66]

[67] [68]

15

measurements: performances of the association of wellknown mathematical models. Energy Convers Manag 2006;47:816e1829. Ghosh HR, Bhowmik NC, Hussain M. Determining seasonal optimum tilt angles, solar radiations on variously oriented, single and double axis tracking surfaces at Dhaka. Renew Energy 2010;35(6):1292e7.  _ ¨ RK TOGRUL TU Inci. Estimation of solar radiation from angstroms coefficients by using geographical and meteorological data in Bishkek, Kyrgyzstan, Isı Bilimi ve  i Dergisi. J Therm Sci Technol 2009;29(2):99e108. 2009. Teknig Hottel HC. A simple model for estimating the transmittance of direct solar radiation through clear atmospheres. Solar Energy U. S. A 1976;18:129e34. ^nia Vieira da Silva M, Sandro de Arau´jo A, Ricardo Euge Queiroz Medeiros M. Adjustment of the clear sky coefficients for the transmission of solar radiation under the ambient conditions in Fortaleza. In: RIO 02-world climate & energy event; January 6e11, 2002. Markvart T. Solar electricity. second ed. New York: John Wiley and Sons Inc; 1996. Hossein Mousazadeh A, Alireza Keyhani A, Arzhang Javadi B, Hossein Mobli A, Karen Abrinia C, Ahmad Sharifi B. A review of principle and sun-tracking methods for maximizing solar systems output. Renew Sustain Energy Rev 2009;13:1800e18. Ouagued M, Khellaf A, Loukarfi L. Estimation of the temperature, heat gain and heat loss by solar parabolic trough collector under Algerian climatic using different thermal oil. Energy Convers Manag 2013;75:191e2013. Ouagued M, Khellaf A. Simulation of the temperature and heat gain by solar parabolic trough collector in Algeria. World Acad Sci Eng Technol 2012;67:802e8. Dincer I, Rosen MA. Exergy: energy, environment and sustainable development. London: Elsevier, UK; 2007. Heintz A. Solar energy combined with chemical reactive systems for the production and storage of sustainable energy. A review of thermodynamic principles. J Chem Thermodyn 2012;46:99e108. Moran MJ, Shapiro HN. Fundamentals of engineering thermodynamics. sixth ed. USA: Wiley; 2007. Elder R, Allen R. Nuclear heat for hydrogen production: coupling a very high/high temperature reactor to a hydrogen production plant. Prog Nucl Energy 2009;51:500e25.

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