8/10/2019 Performance Evaluation of Concentrating Solar Photovoltaic

http://slidepdf.com/reader/full/performance-evaluation-of-concentrating-solar-photovoltaic 1/7

Performance evaluation of concentrating solar photovoltaicand photovoltaic/thermal systems

Monia Chaabane a,⇑, Wael Charfi b, Hatem Mhiri a, Philippe Bournot c

a Unite de thermique et thermodynamique des procedes industriels, Ecole Nationale d’Ingenieurs de Monastir, route de Ouardanine, 5000 Monastir, Tunisiab Institut supe rieur des e tudes technologiques de Tozeur, BP 150 Tozeur 2200, Tunisia

c IUSTI, UMR CNRS 6595, 5 Rue Enrico Fermi, Technopo le de Cha teau- Gombert, 13013 Marseille, France

Received 4 March 2013; received in revised form 12 September 2013; accepted 18 September 2013Available online 7 November 2013

Communicated by: Associate Editor G.N. Tiwari

Abstract

Hybrid conversion of solar radiation, which allows simultaneous conversion of sunlight into thermal and electrical energy in thephotovoltaic/thermal collector, is one of the most promising techniques of solar energy exploitation. In this study, low concentratingphotovoltaic (PV) and photovoltaic/thermal (PVT) systems were designed and tested for a given spring climatic condition of the TunisianSaharan city Tozeur. The system is basically an asymmetric compound parabolic photovoltaic concentrator. As this system’s perfor-mance deteriorates with rising the solar cells temperature, we proposed to convert it on a hybrid one in order to improve its electricalefficiency and to recuperate simultaneously thermal energy. The comparison of these systems operating confirmed the improvement of the electrical performance of the combined PVT system and its acceptable thermal energy production. A computational fluid dynamics“CFD” model which interprets the PVT system was then developed and validated against the experimental results, proving the validity of the developed model use to identify numerically this system limitations and predict the possible improvements. 2013 Elsevier Ltd. All rights reserved.

Keywords:   Concentrating photovoltaic system (CPVS); Concentrating photovoltaic/thermal system (CPVTS); CFD simulation; Performance analysis

1. Introduction

Hybrid photovoltaic/thermal (PVT) solar systems areless expensive devices than the two separate units whichcan simultaneously provide electricity and heat with higherconversion rates of the absorbed solar radiation than stan-

dard PV modules. During the last two decades, the utiliza-tion of this solar technology was the subject of severaltheoretical and experimental studies, helping to sort outsuitable products and systems with the best performance.Ibrahim et al. (2011)  presented the performance of water,

air and combination of water and air systems for a flatPVT collector. This review has considered different designsand indicated that the most important factors that influ-ence the efficiency of the system are the area where the col-lector is covered, the number of passes and the gap betweenthe absorber and solar cells. Similarly, Mishra and Tiwari

(2013)  studied the effect of the collector area covered byPV module on the performance of hybrid PVT water col-lector. They considered two configurations in which thecollector is partially and fully covered by PV module andcompared their results with those of a conventional flatplate collector. Ghani et al. (2012) considered a PVT collec-tor of various design, geometric shape and operating char-acteristics and discussed the effect of non-uniform flowdistribution on the thermal and electrical performance of their solar system.   Li et al. (2011a)   characterized

0038-092X/$ - see front matter    2013 Elsevier Ltd. All rights reserved.

http://dx.doi.org/10.1016/j.solener.2013.09.029

⇑ Corresponding author. Tel.: +216 97 22 44 72; fax: +216 73 50 05 14.E-mail addresses: monia.chaabane@yahoo.fr (M. Chaabane), e_charfi

@yahoo.fr   (W. Charfi),   hatem.mhiri@enim.rnu.tn   (H. Mhiri),bournot@univmed.fr  (P. Bournot).

www.elsevier.com/locate/solener

Available online at www.sciencedirect.com

ScienceDirect 

Solar Energy 98 (2013) 315–321

8/10/2019 Performance Evaluation of Concentrating Solar Photovoltaic

http://slidepdf.com/reader/full/performance-evaluation-of-concentrating-solar-photovoltaic 2/7

experimentally the thermal and electrical performance of a2 m2 PVT system. These experiments were done for threedifferent types of solar cells and the optimal design wasevaluated. In other investigation,   Li et al. (2011b)   evalu-

ated the overall performance of a 10 m2

CPVTS and dis-cussed the effect of the solar cell array on its thermal andelectrical efficiency. In order to improve the performanceof this system, a 2 m2 PVT system utilizing a mirror of higher reflectivity was then built and its contribution tothe effective operating of the PVT system was presentedregarding its thermal efficiency.  Ji et al. (2007)  considereda solar system which consists of a flat-box aluminum-alloyphotovoltaic and water-heating system with single-crystalline silicon cells integrated. Dynamic simulationswere performed and the effect of the PV cell covering factorand the glazing transmissivity on the overall system perfor-mance were discussed. Garg and Agarwal (1995) proposeda conversion of a conventional water heater into a com-bined system by pasting solar cells directly over the absor-ber plate. This study was done for different solar cell areas,mass flow rates and different water masses, and indicatedthe optimal flow rate for a maximum efficiency. Similarly,the effect of the mass flow rate on the thermal and electricalefficiency of a PVT air system was studied by  Bambrookand Sproul (2012) who showed that their solar system per-forms better for high values of the air mass flow rate.Another integrated combined PVT solar water heating sys-tem was designed and tested outdoor New Delphi climateby   Dubey and Tiwari (2008)   who discussed the effect of 

the design and the climatic conditions on the system oper-ation. Bernardo et al. (2011) proposed a complete method-ology to simulate a PVT collector and presented acomparison of their system performance relatively to astandard PV module and a flat plate collector.   Cristofariet al. (2009) developed a simulation model of finite differ-ences describing the operating of a hybrid PVT collectorand noted the importance of the utilization of a copolymerfor the total design of the solar collector.   Tiwari et al.(2009) were based on the energy balance and discussed ana-lytically the performance of an integrated PVT solar systemregarding the water temperature, the exergy and the

thermal and electrical efficiency for different hot water

withdrawal flow rates. Regarding the strategies proposedto improve these systems performance and in order to getmore thermal and electrical energy, reflectors weremounted by Kostic et al. (2010)  in the PVT collector and

their position was changed to evaluate the optimal one.Similarly, for additional power production,  Kosmadakiset al. (2011)  presented a feasibility study of a CPVTS inwhich the heat produced is recovered by an organic Ran-kine cycle. Results showed the effectiveness of the changeregarding the electrical production increase, the PV cellscooling and the system electrical efficiency improvement.A novel technology which consists of coupling a linearFresnel concentrator with a channel PVT collector in orderto increase the solar conversion efficiency was described byRosell et al. (2005). Theoretical analyses of this solarsystem were presented, confirming the importance of thethermal conduction between the PV cells and the absorberplate. Another novel hybrid PVT system was studied byRajoria et al. (2013)   who were interested to the exergeticand enviroeconomic analysis.   Tripanagnostopoulos(2007)  presented an experimental study of a new type of PVT collector with dual heat extraction operation, eitherwith air or water circulation. The most effective designwas studied, and low cost modifications were applied toimprove the system thermal and electrical energy output.Kostic et al. (2010) studied the influence of reflectance fromflat plate solar radiation concentrators made of Al sheetand Al foil on energy efficiency of a PVT collector. Thiswork discussed also the optimal position of solar radiation

concentrators and appropriate thermal and electrical effi-ciency of the PVT collector were determined.   Tiwari andSodha (2006) developed a thermal model of an integratedphotovoltaic and thermal solar system. The numerical sim-ulations were carried out for different climatic and designparameters, and a daily thermal efficiency of 58% was pre-dicted. Corbin and Zhai (2010) proposed an experimentallyvalidated computational fluid dynamics (CFD) model of anovel building integrated PVT collector. They discussed theeffect of active heat recovery on cell efficiency and studiedthe effectiveness of the device as a solar water heater. In thisreview, a new correlation which allows cell efficiency to be

calculated directly was also developed, relating electrical

Nomenclature

G    solar irradiance, W/m2

hcv  convective heat transfer coefficient, W/m2K

I    current, A

k    turbulent kinetic energy, m

2

s

2

_m   water mass flow rate, l/sP    electrical power, WT    temperature,   CT a

  ambient temperature,   CT e   sky temperature,   C

U    voltage, V

Greek letters

D   Kronecker delta, dimensionless

b   thermal expansion coefficient, K1

e   dissipation rate of the turbulent kinetic energy,m2/s3

gel   electrical efficiency, dimensionlessgth   thermal efficiency, dimensionlessq   density, kg/m3

316   M. Chaabane et al. / Solar Energy 98 (2013) 315–321

8/10/2019 Performance Evaluation of Concentrating Solar Photovoltaic

http://slidepdf.com/reader/full/performance-evaluation-of-concentrating-solar-photovoltaic 3/7

efficiency to collector inlet water temperature, ambient airtemperature and insulation. Another numerical modelwas developed by   Ji et al. (2006)   to analyze the perfor-mance of a hybrid PVT system. In this study, the combinedeffects of the solar cell packing factor and the water massflow rate on the thermal and electrical efficiency were inves-

tigated.  Kalogirou and Tripanagnostopoulos (2006)   usedthe TRNSYS software to simulate hybrid PVT solarsystems for domestic hot water applications and showedthe considerable amount of thermal and electrical energyproduced by these systems.

Despite the fact that all these authors are in agreementthat the increasing cells temperature has an adverse effecton the PV system electrical performance and that thePVT system presents improved electrical performance inaddition to its thermal energy production, there is limitedexperimental data on how much is the electrical and ther-mal gain reached by the PV system conversion on a PVTsystem. In this experimental study, the performance of a

CPVS is firstly studied, this system is then converted on aCPVTS and the resulting thermal and electrical gain isevaluated. Similarly, Computational fluid dynamics CFDwas not used to model concentrating PVT systems andthe few CFD studies encountered concern non-concentrat-ing systems. In the numerical part of this study, the perfor-mance of a CPVTS is studied using the CFD packageFluent 6.3 and the developed CFD model is validated bycomparing numerical results to the experimental data.

This paper presents so experimental results of concentrat-ing PV and PVT systems constructed and analyzed under aTunisian Saharan climate. The first system, which is the

PV one, consists of the concentrator, the receiver which rep-resents the PV module and the electrical energy output sys-tem. As the rising solar cell temperature causes a reductionof the system electrical efficiency in addition to the risks thatthe cells exhibit long-term degradation if the temperatureexceeds a certain limit, we propose to convert this PV systeminto a combined PVT one. A rectangular conduct dimen-sioned according to the characteristics of the solar PV panelis so constructed and this system electrical performance isanalyzed and compared to that of the PV system. The PVTsystem thermal performance is also evaluated for two watermass flow rates. A 3D CFD model describing the CPVTSoperation is then developed and numerical results are vali-dated against the experimental data.

2. Experimental models

 2.1. CPVS 

The CPVS test device includes the concentrator and thePV panel. The concentrator is made of stainless steel; it is3.64 m long and 2 m wide. The PV panel is an STP020S-12/cb panel of 18 single crystalline silicon solar cells andits specifications are detailed in   Table 1. The experiments

have been conducted for a Tunisian Saharan climate, in

the city of Tozeur and the CPVS was south facing and34  titled above the horizontal.

 2.2. CPVTS 

The CPVTS consists of a thermal unit for the heat

extraction by the water which circulates through the rect-angular pipe and the PV module which are mountedthrough the concentrating system. A rectangular conductis so constructed and installed in contact with the PV cells,allowing simultaneously the PV cells cooling and thethermal energy production. The length of this conduct is1.825 m, its width is 0.275 m and its depth is 0.05 m.The PV panel is positioned in the middle of the water con-duct so that the flow is fully developed in the contact of these two surfaces. The black painted steel waterconduct, the PV panel and the whole CPVTS are describedin Fig. 1.

 2.3. Analyzed parameters and measuring instruments

For the calculation of the PV system electrical output,the current  I  and the voltage  V  are measured. Some mete-orological parameters such as the ambient temperature  T 

a

and the solar irradiance   G   are also experimentally deter-mined in order to evaluate the system electrical efficiencywhich is function of the operating conditions. Regardingthe CPVTS operation, these same parameters are mea-sured, in addition to the water inlet and outlet tempera-tures which are used for the system thermal efficiencycalculation.

The measuring equipments characteristics are listed inTable 2.

The conversion relation of the solarimeter used in theseexperiments is: 100 mV 1000 W/m2

 2.4. Experimental results

 2.4.1. CPVS performance

The current   U   and the voltage   I   delivered by the PVpanel were measured and the CPVS electrical power   P 

which is defined as their product was then calculated.The uncertainty in the experimental values is calculatedas proposed by Kratzenberg et al. (2006) and the electricalefficiency is evaluated as demonstrated by  Kalogirou andTripanagnostopoulos (2006). These experimental investiga-tions were undertaken on the 31st of May 2012 and mea-surements have been continuously monitored each ½ h,from 6 am to 6 pm.

The climatic conditions described by the solar irradianceand the ambient temperature were also monitored. Duringthese experiments, the highest intensity of incident solarirradiance was of about 850 Wm2, the maximum averageambient temperature was of 38  C and they were respec-tively measured at 12 h and 16 h.

The temporal evolution of the CPVS electrical power as

well as this system electrical efficiency is shown in Fig. 2. A

M. Chaabane et al./ Solar Energy 98 (2013) 315–321   317

8/10/2019 Performance Evaluation of Concentrating Solar Photovoltaic

http://slidepdf.com/reader/full/performance-evaluation-of-concentrating-solar-photovoltaic 4/7

maximum power of 13.8 W is measured at about 13 h 30and the system maximum electrical efficiency which is of 0.095 is measured at about 14 h 30.

 2.4.2. CPVTS performance

Due to the negative temperature coefficient which char-acterizes the photovoltaic cells, the increase of the PV cellstemperature causes a reduction of the system efficiency.This problem can be limited by the application of a heatextraction mode which allows the solar cells cooling. Theapplication of a suitable cooling system is so the next stepof this work and its contribution to the effective systemoperation is discussed regarding its electrical performance,in addition to the thermal efficiency evaluated as proposed

by   Li et al. (2011a). Measurements have also been per-formed each ½ h, from 6 h to 18 h and that during two suc-cessive days, June 4th and 5th and for two different watermass flow rates, respectively 0.05 and 0.0187 l/s.

Fig. 3 shows the effect of the water mass flow rate on thedaily variation of the electrical power delivered by the

CPVTS and its electrical efficiency. From the presentedresults of this figure, one can see that with a mass flow rateof 0.05 l/s, the electrical power is higher than that for amass flow rate of 0.0187 l/s. Regarding the effect of thewater flow rate on the CPVTS electrical efficiency, the cellefficiency can be seen improved in stages as the mass flowrate increases. Indeed, the maximum electrical efficiencyachieved by the CPVTS is respectively of 9.8% and10.02% for the corresponding water mass flow rates of 0.087 l/s and 0.05 l/s, whereas that of the CPVS is of 9.4%.

In addition to the climatic conditions described by theambient temperature and the solar irradiance, the waterinlet and outlet temperature was also measured in order

to evaluate the system thermal efficiency. The thermal effi-ciency of the CPVTS is illustrated for the considered watermass flow rates in Fig. 4 and this CPVTS thermal efficiencycan be written as a function of the temperature rise DT  andthe solar irradiance  G  as follows:

CPVTS with a water mass flow rate of 0:0187 l=s   :

gth  ¼ 0:161 5:719  DT  =G :

CPVTS with a water mass flow rate of 0:05 l=s  :

gth  ¼ 0:161 7:048  DT  =G :

Table 1Photovoltaic module characteristics.

Parameter Value

Maximum power at STC (P  max) 20 WOptimum operating voltage (U  mp) 17.6 VOptimum operating current (I  mp) 1.14 AShort-circuit current (I  sc) 1.26 A

Open circuit voltage (U  oc) 21.7 VShort- circuit current temperature

coefficient(0.055 ± 0.01) (%/K)

Open circuit voltage temperaturecoefficient

(78 ± 10) (mV/k)

Peak power temperature coefficient   (0.48 ± 0.05) (%/K)Convective heat transfer coefficient  hcv   13 W/m2 KElectrical efficiency at STC gel   10%Dimensions of cell 125 mm 31.25 mmDimensions of module 656 mm 306 mm 18 mm

Fig. 1. photographic picture of the CPVTS.

Table 2Equipments used for the experimental study measures.

Parameter Unit Measuring instrument Model

fluid temperature T   C Fluke Fluke 63Solar irradiance G    mV Solarimeter CR 100Current  I    A Compact digital multimeter Amprobe AM-240Voltage  V    V Compact digital multimeter Amprobe AM-240

www.suntech-power.com, www.suntech-power.com

318   M. Chaabane et al. / Solar Energy 98 (2013) 315–321

8/10/2019 Performance Evaluation of Concentrating Solar Photovoltaic

http://slidepdf.com/reader/full/performance-evaluation-of-concentrating-solar-photovoltaic 5/7

It is noted that the lower loss factor corresponds to thewater mass flow   _m = 0.0187 l/s but even for the mass flowvalue   _m = 0.05 l/s, the corresponding daily thermal lossescoefficient remains acceptable.

Based on these experiments, a detailed analysis of CPVSand CPVTS is performed; highlighting the advantage of theCPVTS regarding its electrical and thermal performance.Indeed, the CPVS conversion on a CPVTS resulted in an

improvement of the system’s electrical efficiency which

reached 10.02% for a water mass flow rate of 0.05 l/s.Experimental results also showed that this solar system ismore efficient for high water mass flow rates. In additionto the electrical performance considerations, experimentsare considered encouraging for the PVT conversion of thissystem regarding the relatively important thermal energy

output. Indeed, a thermal efficiency of 16% is obtainedand a combined (thermal and electrical) efficiency of 26%is reached in spite of the simplicity and low cost of thechange.

3. D CFD modeling

This paper describes a first detailed simulation of aCPVTS. Based on the experiment tests, the studied solarsystem is defined, the mesh is generated, the boundary con-dition are identified then introduced for the CFD simula-tion and numerical results are compared to experimentaldata.

3.1. Geometry description and meshing 

The same dimensions, materials and properties of theexperimentally investigated PVT system are introducedfor the CFD simulation. The mesh generated in the entirefield of this system consists of tetrahedral cells in the solarcells and PV panel and of hexahedral cells in the rest of thefield. A grid independent study was also carried out and theoptimum mesh size which was obtained with 604836 cellswas used.

3.2. Assumptions and boundary conditions

The experimental validation of the PVT model has beenfocused on the system thermal and electrical efficiency. Theperformance of the developed model has been tested bysimulating the PVT system over the 12 daily hours of day-light and for the experimentally investigated water massflow rates. The same conditions as those of the experimen-tal tests were considered and a tilt of 34  above the hori-zontal was simulated in CFD by considering a rotationof the gravitational forces by this angle in the southdirection.

The simplifying assumptions considered in this analysisare:

(1) incompressible fluid;(2) climatic conditions corresponding to fair weather

conditions;(3) in the analysis of natural convection flows, the fluid

properties can be assumed constant except for thedensity change with temperature which is consideredfor the air, described by the Boussinesq approxima-tion, and expressed as follows:

q ¼ q0ð1 bDT  Þ ð1Þ

Fig. 2. Temporal evolution of the electrical power and efficiency of theCPVS.

Fig. 3. Variation of the electrical power and efficiency of the CPVTS withwater mass flow rate.

Fig. 4. Variation of the CPVTS thermal efficiency with flow rate.

M. Chaabane et al./ Solar Energy 98 (2013) 315–321   319

8/10/2019 Performance Evaluation of Concentrating Solar Photovoltaic

http://slidepdf.com/reader/full/performance-evaluation-of-concentrating-solar-photovoltaic 6/7

Boundary conditions: the experimental results of the mete-orological data collected on the global irradiance andambient temperature were used as input for the CFD sim-ulation. The external sky temperature  T e  required to esti-mate the radiative exchange was introduced as a userdefined function UDF and its variation according to the

ambient temperature is expressed as follows:T  e  ¼ 0:0552T  1:5

a  ð2Þ

In addition to these parameters, the temporal evolution of the water inlet temperature was also taken from measure-ments and introduced as a user defined function UDF inthe CFD model.

3.3. Numerical procedure

The governing equations employed for modeling theflow and heat transfer in the air and water gaps of the

CPVTS are the Navier Stockes conservation equationsfor a tri-dimensional turbulent flow, written under theBoussinesq assumption. For the closure of these equations,we considered the standard   K  – e   turbulence model whichpresents the advantage of a fast calculation time in additionto its good prediction for such flows (Corbin and Zhai,2010). For the radiative energy introduction, we chosethe surface to surface (S2S) model as it is used to accountfor radiative exchange in an enclosure of gray and diffusesurfaces, which describes the well the CPVTS experimen-tally studied. Regarding the accuracy of the result, the con-tinuity, velocity and turbulence terms are solved withconvergence criteria of 104, while a value of 106 isimposed for the energy. A 2nd order upwind scheme is cho-sen to discretize the velocity, the turbulent kinetic energy,the turbulent dissipation rate and the energy, while the Pre-sto scheme is chosen for the pressure discretization.

3.4. Simulation results

The simulation of the PVT system was run under thesame experimental conditions, the water outlet temperatureis evaluated and the corresponding PVT system thermalefficiency is calculated and compared to that experimen-tally investigated. Results are presented for the fluid mass

flow rate of 0.05 l/s in  Fig. 5 and this system thermal effi-ciency is written as a linear function of the quotient   DT /G  as follows:

Experimental result  :  gth  ¼ 0:161 7:048DT  =G :

Numerical result  : gth ¼ 0:161 8:54DT  =G :

The analysis of these results shows a good agreementbetween numerical and experimental data.

Similarly, the system electrical efficiency is calculatedand numerical results are compared in Fig. 6 to experimen-tal data showing a good agreement which proves the cred-ibility of the CFD model.

So a detailed numerical characterization of a PVT sys-tem mounted trough a concentrator was undertaken anda good agreement between numerical results and the exper-imental data was seen, proving the validity of this numeri-

cal model use for the corresponding system performanceimprovement.

4. Conclusion

The simultaneous experimental characterizations of concentrating PV and PVT systems have been undertakenin this work. The electrical production of these systems hasbeen monitored over a summer day of the Tunisian Saha-ran city Tozeur and their electrical efficiency was then eval-uated. In addition to the electrical considerations, thethermal performance of the CPVTS is evaluated for twodifferent water mass flow rates. The results showed that

the consideration of a CPVTS allows higher electricalpower output and electrical efficiency compared to theCPVS, in addition to its important thermal output.Regarding the effect of the water mass flow rate, it is notedthat the best electrical performance corresponds to thehighest value of the water mass flow rate, unlike the ther-mal performance where the optimal case is obtained forthe lowest value. Computational fluid dynamics CFDwas also used to model experimental data correspondingto the PVT system operating and a satisfactory agreementwas received justifying this numerical model use to performparametric studies helping to study the possible improve-

ments and to evaluate this system optimal design.

Fig. 5. Comparison of numerical results of the PVT system thermal

efficiency with experimental data.

Fig. 6. Comparison of numerical results of the PVT system electricalefficiency with experimental data.

320   M. Chaabane et al. / Solar Energy 98 (2013) 315–321

8/10/2019 Performance Evaluation of Concentrating Solar Photovoltaic

http://slidepdf.com/reader/full/performance-evaluation-of-concentrating-solar-photovoltaic 7/7

Further work on this project would involve the numer-ical investigation of the effect of mounting geometryparameters on the performance of the PVT system in orderto maximize its thermal and electrical production.

References

Bambrook, S.M., Sproul, A.B., 2012. Maximizing the energy output of aPVT air system. Solar Energy 86, 1857–1871.

Bernardo, L.R., Perers, B., Hakansson, H., Karlsson, B., 2011. Perfor-mance evaluation of low concentratind photovoltaic/thermal systems:A case study from Sweden. Solar Energy 85, 1499–1510 .

Corbin, Charles D., Zhai, Zhiqiang John, 2010. Experimental andnumerical investigation on thermal and electrical performance of abuilding integrated photovoltaic–thermal collector system. Energy andBuildings 42, 76–82.

Cristofari, Christian, Notton, Gilles, Canaletti, Jean Louis, 2009. Thermalbehavior of a copolymer PV/T solar system in low flow rateconditions. Solar Energy 83, 1123–1138.

Dubey, Swapnil, Tiwari, G.N., 2008. Thermal modeling of a combinedsystem of photovoltaic thermal (PV/T) solar water heater. SolarEnergy 82, 602–612.

Garg, H.P., Agarwal, R.K., 1995. Some aspects of a PV/T collector/forcedcirculation flat plate solar water heater with solar cells. EnergyConversion and Management 36 (2), 87–99.

Ghani, F., Duke, M., Carson, J.K., 2012. Effect of flow distribution on thephotovoltaic performance of a building integrated photovoltaic/thermal (BIPV/T) collector. Solar Energy 86, 1518–1530.

Ibrahim, Adnan, Othman, Mohd Yusof, Ruslan, Mohd Hafidz, Mat,Sohif, Sopian, Kamaruzzaman, 2011. Recent advances in flat platephotovoltaic/thermal (PV/T) solar collectors. Renewable and Sustain-able Energy Reviews 15, 352–365.

Ji, Jie, Han, Jun, Chowb, Tin-Tai, Yi, Hua, Jianping, Lu, He, Wei, Sun,Wei, 2006. Effect of fluid flow and packing factor on energyperformance of a wall-mounted hybrid photovoltaic/water-heatingcollector system. Energy and Buildings 38, 1380–1387.

Ji, Jie, Jian-Ping, Lu, Chow, Tin-Tai, He, Wei, Pei, Gang, 2007. Asensitivity study of a hybrid photovoltaic/thermal water-heatingsystem with natural circulation. Applied Energy 84, 222–237.

Kalogirou, S.A., Tripanagnostopoulos, Y., 2006. Hybrid PV/T solarsystems for domestic hot water and electricity production. EnergyConversion and Management 47, 3368–3382.

Kosmadakis, G., Manolakos, D., Papadakis, G., 2011. Simulation andeconomic analysis of a CPV/thermal system coupled with an organicRankine cycle for increased power generation. Solar Energy 85, 308– 324.

Kostic, Lj.T., Pavlovic, T.M., Pavlovic, Z.T., 2010. Optimal design of orientation of PV/T collector with reflectors. Applied Energy 87, 3023– 3029.

Kostic, Ljiljana T., Pavlovic, Tomislav M., Pavlovic, Zoran T., 2010.Influence of reflectance from flat aluminum concentrators on energyefficiency of PV/Thermal collector. Applied Energy 87, 410– 416.

Kratzenberg, M.G., Beyer, H.G., Colle, S., 2006. Uncertainty calculationapplied to different regression methods in the quasi-dynamic collectortest. Solar Energy 80, 1453–1462.

Li, M., Li, G.L., Ji, X., Yin, F., Xu, L., 2011a. The performance analysisof the trough concentrating solar photovoltaic/thermal system. EnergyConversion and Management 52, 2378–2383.

Li, M., Ji, X., Li, G.L., Yang, Z.M., Wei, S.X., Wang, L.L., 2011b.Performance investigation of the Trough concentration Photovoltaic/Thermal system. Solar Energy 85, 308–324.

Mishra, R.K., Tiwari, G.N., 2013. Energy and exergy analysis of hybridphotovoltaic thermal water collector for constant collector tempera-ture mode. Solar Energy 90, 58–67.

Rajoria, C.S., Agrawal, Sanjay, Tiwari, G.N., 2013. Exergetic andenviroeconomic analysis of novel hybrid PVT array. Solar Energy88, 110–119.

Rosell, J.I., Vallverdu, X., Lecho, M.A., Iba~nez, M., 2005. Design andsimulation of a low concentrating photovoltaic/thermal system.Energy Conversion and Management 46, 3034–3046.

Tiwari, Arvind, Sodha, M.S., 2006. Performance evaluation of solar PV/Tsystem: An experimental validation. Solar Energy 80, 751–759.

Tiwari, Arvind, Dubey, Swapnil, Sandhu, G.S., Sodha, M.S., Anwar, S.I.,2009. Exergy analysis of integrated photovoltaic thermal solar waterheater under constant flow rate and constant collection temperaturemodes. Applied Energy 86, 2592–2597.

Tripanagnostopoulos, Y., 2007. Aspects and improvements of hybridphotovoltaic/thermal solar energy systems. Solar energy 81, 1117– 1131.

M. Chaabane et al./ Solar Energy 98 (2013) 315–321   321