Ci a ion: Elango an, M.;
S imanickam, B.; ˇ
Cep, R.; Sa anya, A.;
Ramachand an, M. Expe imen al
S udy o a Hyb id Sola Collec o
Using TiO2/Wa e Nano luids.
Ene gies 2022,15, 4425. h ps://
doi.o g/10.3390/en15124425
Academic Edi o s: Gianpie o
Colangelo and Geo ge Kosmadakis
Recei ed: 21 May 2022
Accep ed: 16 June 2022
Published: 17 June 2022
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ene gies
A icle
Expe imen al S udy o a Hyb id Sola Collec o Using
TiO2/Wa e Nano luids
Muniyandy Elango an 1,* , Baska an S imanickam 1, Robe ˇ
Cep 2,* , Ami ha ajan Sa anya 3
and Manickam Ramachand an 4
1Depa men o Mechanical Enginee ing, Vel Tech Ranga ajan D . Sagun hala R&D Ins i u e o Science and
Technology, Chennai 600062, India; [email p o ec ed]
2Depa men o Machining, Assembly and Enginee ing Me ology, Facul y o Mechanical Enginee ing,
VSB-Technical Uni e si y o Os a a, 708 00 Os a a, Czech Republic
3Depa men o Physics, Vel Tech Ranga ajan D . Sagun hala R&D Ins i u e o Science and Technology,
Chennai 600062, India; [email p o ec ed]
4Da a Analy ics Lab, REST Labs, Ka e ipa inam, K ishnagi i 635112, India;
[email p o ec ed]
*Co espondence: [email p o ec ed] (M.E.); [email p o ec ed] (R. ˇ
C.)
Abs ac :
A case s udy o sola collec o ou doo es o he expe imen al echnique conduc ed a
A adi, Chennai. To lowe he empe a u e o sola PV panels, wa e , and wa e -based nano luids we e
u ilized concu en ly. Highe cell empe a u es es ic he e ec i eness o sola PV sys ems since
only a mino amoun o powe om he sun is ga he ed as elec ici y om he ene gy con e sion,
and he emaining ene gy is squande ed as hea . The s udy aimed o de elop and build a hyb id
collec o while also analyzing i s elec ical and he mal ene gy pe o mance. The e o was in es ed
in imp o ing he sys em’s pe o mance; he PVT collec o was es ed a olume concen a ions o wo,
such as 0.5 and 1.0 L pe minu e (LPM). The PV/T collec o de e mined he mal e iciency as highes
was 48.38 pe cen and 54.03 pe cen , espec i ely, a 0.5 LPM and 1.0 LPM o olume low a es.
The PV/T collec o ’s highes elec ical e iciency was 18.32 pe cen and 19.35 pe cen , espec i ely,
o 0.5 LPM and 1.0 LPM o olume low a es. The esul s demons a e ha nano luid has mo e
excellen he mal conduc i i y han a base luid wi h a li le change in he luid iscosi y and densi y.
Keywo ds:
s andalone hyb id collec o ; TiO
2
; low a e; nano luid; he mal pe o mance; elec ical;
ene gy; enewable
1. In oduc ion
The inc ease in global ene gy equi emen s e e y yea , and he g adual deple ion
o adi ional uels necessi a es echnological ad ancemen s based on al e na i e ene gy
sou ces [
1
]. Sola collec o s o indus ies and households a e equen ly used o hea
wa e wi h sola ene gy. Ou o wo collec o s, one is called a Sola la pla e collec o
and he o he is called an e acua ed ube collec o . To inc ease p oduc i i y, wo di e en
powe con e sion sys ems, known as hyb id powe o pho o ol aic he mal sys ems, can
be coupled oge he [
2
,
3
]. Sola enewable ene gy is a popula enewable sou ce because i
is ee, easible, du able, has a low main enance cos , is en i onmen ally iendly, and has a
wide ange o applica ions. Howe e , i has d awbacks, such as inc easing he sola panel’s
empe a u e by 10 deg ees Celsius, esul ing in a 0.5 pe cen dec ease in elec ical e iciency
o silicon cells because cooling o he sola panel may be equi ed o imp o ed e iciency.
Cooling liquids such as ai o wa e a e used in he sola panel sys em o educe
he empe a u e [
4
–
9
]. The e a e wo ways ha he pe o mance o a sola panel can be
inc eased. Fi s is sola panel cooling, and ano he is a medium o s o ing was e hea .
Ai and wa e a e commonly used o cool sola panels as a adi ional cooling me hod.
None heless, i has i s own se o i ues and me i s. As a esul o he o egoing encoun e s,
Ene gies 2022,15, 4425. h ps://doi.o g/10.3390/en15124425 h ps://www.mdpi.com/jou nal/ene gies
Ene gies 2022,15, 4425 2 o 12
many esea che s wo ldwide ha e been using nanoma e ials as a supe io cooling luid
o imp o e he mal and elec ical pe o mance. As a esul , o e all pe o mance can be
imp o ed. The ollowing a e some examples o success ul s udies conduc ed a ound he
wo ld. Choi and Es man [
10
] pionee ed nano luids as a coole in PVT sys ems, which
spa ked conside able in e es due o hei supe io he mophysical p ope ies examined
o he s anda d luids. The solid-liquid syn hesized nanopa icles in a company wi h
diame e s ypically anging om 1–100 nm d i ing in wa e [11].
Many expe imen s demons a ed ha wa e nano luid has a signi ican ly la ge hea
ans e coe icien occu s han basic luids [
12
–
14
]. The en ichmen o hea ans e was
done by nano luids in hyb id collec o s, wi h a ew nega i e impac s, such as inc eased
p essu e d op in he sys em [
15
], a limi ed pe iod o i s s abili y, and a highe cos o
nanopa icles. Sa da abadi e al. [
16
] expe imen ed wi h wa e as a base luid wi h PVT
sys ems and a a ious concen a ions o SiO
2
nano luid. I was concluded ha o e all
pe o mance a ained 3.6 o 7.9 pe cen o 1 o 3 w . pe cen . Ghadi i e al. [
17
] examined
wa e and e o luid wi h a ying composi ions using an indoo PVT sys em. The o e all
e iciency was 45 pe cen when compa ed o a hyb id sys em. Sa da abadi e al. [
18
] used
deionized wa e o dissol e h ee ypes o nanopa icles (AL2O3, TiO2, and ZnO).
Al-shamani e al. [
19
] expe imen ed wi h a ious nano luids a di e en low a es.
Acco ding o he esul s, sic had he highes elec ical pe o mance o abou 13.52 pe cen
and he o e all maximum e iciency o 78.24 pe cen . Sol ani e al. [
20
] demons a ed an
in es iga ional s udy in a hyb id sys em using wa e nano luid. I was disco e ed ha ull
enac men and powe gene a ion inc eased by 3.13 pe cen and 52.4 pe cen , espec i ely.
The au ho s also e ealed ha SiO
2
imp o ed o al pe o mance and powe gene a ion by
3.29 pe cen and 43.36 pe cen , espec i ely. Al-Waeli e al. [
21
] used collec o s o in es iga e
h ee ypes o nano luids.
Al-Waeli e al. [
22
] demons a ed he in luence o Silicon chlo ide/wa e nano luid on
hyb id sys ems, which imp o ed elec ical ene gy e iciency o 23.9 pe cen and hea powe
e iciency o 99.23 pe cen . I also disco e ed ha i had a supe io o e all pe o mance
o app oxima ely 88.9 pe cen when compa ed o a PV sys em. Mohammad Sa da abadi
e al. [
23
] examined he silica nano luid’s e iciency in a PVT sys em expe imen ally. I
concluded wi h a 7.9 pe cen imp o emen in o e all pe o mance and a 24.3 pe cen
imp o emen in exe gy. Fo long- e m s abili y, Ag/wa e nano luid was p ocessed by
elec ical explosion o wi e [
24
,
25
]. The sys em was e alua ed using a he modynamic
s udy, speci ically ene gy and exe gy e iciency. This expe imen was ca ied ou using
a ious low pa e ns and concen a ions.
Muhammad Azam in es iga ed a ma hema ical model o a chemically eac i e Maxwell
nano luid o axisymme ic low using he Ca aneo-Ch is o hea lux model and a e ised
nano luid model. [
26
]. The impac o A henius ac i a ion ene gy and mel ing e en s on
chemically eac i e Falkne -Skan low o c oss nano luid ac oss a mo ing wedge wi h
iscous dissipa ion and nonlinea adia ion impac s a e s udied using a heo e ical nu-
me ical communica ion [
27
]. The p ima y goal o his pape is o in es iga e he e ec s o
mel ing phenomena and nonlinea chemical eac ions on ansien biocon ec ion low o a
su e by nanoliquid wi h gy o ac ic mic oo ganisms and hea sou ce/sink [
28
]. Muham-
mad Azam [
29
] s udied he uns eady bio-con ec ion low o nano luid unde he impac o
mic oo ganisms and nonlinea adia ion using ma hema ical modeling and simula ion.
The esea ch goal is o demons a e manganese chlo ide as a coolan o imp o e he
PVT collec o pe o mance. The manganese chlo ide nano luid has been expe imen ally
explo ed o he i s ime o cool and imp o e he pe o mance o a single glazing su ace
PVT sys em. The de eloped PVT collec o and PV module we e es ed ou doo s a he
Chennai me eo ological s a ion using 0.5 w . pe cen concen a ions o nano luids and pu e
wa e as coolan s a 0.5 and 1.0 L pe minu e. The ene ge ic s udy o a hyb id collec o wi h
nano luid coolan s was ca ied ou , and compa isons o PV modules and wa e -cooled PVT
sys ems we e. I was also disco e ed ha he indings o his inqui y we e equi alen o
hose published in pee - e iewed jou nals.
Ene gies 2022,15, 4425 3 o 12
2. Expe imen al S udy P ocedu e
The indings a e om es s conduc ed in A adi, nea Chennai (The Capi al o Tamil
Nadu, Sou he n India). Chennai ci y is loca ed on he he mal equa o and he coas , which
p e en s seasonal empe a u e a ia ions om becoming conside able. The a e age ela i e
humidi y is 69%, he a e age ambien empe a u e anges om 24.8
◦
C o 33.1
◦
C, and he
a e age numbe o sunshine hou s is 7.8. The sugges ed app oach was buil , p oduced,
and es ed o de e mine he e iciency o nano-PCM and nano luid PVT sys ems, hen
compa ed o liquid PVT sys ems and ees anding PV modules. In addi ion, wa e as a
coole wi h a ied low a es was es ed in he PVT sys em, while nano-PCM and nano luid
wi h a ying concen a ions and low a es we e es ed in he hyb id collec o . The inished
sys em is a sel -con ained PV module ha usually wo ks—an expe imen al se up a he
speci ic loca ion in Figu e 1. As pe he Indian subcon inen is loca ed in he no he n
hemisphe e o he ea h whe e a 13-deg ee inclina ion is measu ed. In his s udy, he e is
no a ia ion in inclina ion.
Ene gies 2022, 15, x FOR PEER REVIEW 3 o 14
pu e wa e as coolan s a 0.5 and 1.0 L pe minu e. The ene ge ic s udy o a hyb id collec o
wi h nano luid coolan s was ca ied ou , and compa isons o PV modules and wa e -
cooled PVT sys ems we e. I was also disco e ed ha he indings o his inqui y we e
equi alen o hose published in pee - e iewed jou nals.
2. Expe imen al S udy P ocedu e
The indings a e om es s conduc ed in A adi, nea Chennai (The Capi al o Tamil
Nadu, Sou he n India). Chennai ci y is loca ed on he he mal equa o and he coas ,
which p e en s seasonal empe a u e a ia ions om becoming conside able. The a e -
age ela i e humidi y is 69%, he a e age ambien empe a u e anges om 24.8 °C o 33.1
°C, and he a e age numbe o sunshine hou s is 7.8. The sugges ed app oach was buil ,
p oduced, and es ed o de e mine he e iciency o nano-PCM and nano luid PVT sys-
ems, hen compa ed o liquid PVT sys ems and ees anding PV modules. In addi ion,
wa e as a coole wi h a ied low a es was es ed in he PVT sys em, while nano-PCM
and nano luid wi h a ying concen a ions and low a es we e es ed in he hyb id col-
lec o . The inished sys em is a sel -con ained PV module ha usually wo ks—an expe i-
men al se up a he speci ic loca ion in Figu e 1. As pe he Indian subcon inen is loca ed
in he no he n hemisphe e o he ea h whe e a 13-deg ee inclina ion is measu ed. In his
s udy, he e is no a ia ion in inclina ion.
Figu e 1. Expe imen al se up a he speci ic loca ion.
A mul i-silicon glass panel wi h 1640 mm × 992 mm × 35 mm was pu chased o con-
s uc a Pho o ol aic The mal Collec o . Because o he pla o m’s insula ing e ec , a 0.4
mm coppe shee was used o hea abso p ion on he back o he sola panel. Fu he -
mo e, he ex e nal and in e nal diame e s o he coppe ube a e 1.0 cm and 0.8 cm, e-
spec i ely, and a e placed o obse e hea behind he sola panel. Table 1 shows he pe -
o mance o he sola panel unde no mal es condi ions. The pho o ol aic he mal sys-
em was o ien ed 13 deg ees sou h. E e y day, be ween 8 a.m. and 5 p.m., eadings o all
wea he condi ions and ou pu powe we e ob ained o i een minu es. A coppe ube
connec ed o a sola panel is shown in Figu e 2. This coppe ube is used because o high
hea conduc ion om he sola panel o he wa e which is passing h ough he pipe. When
placing he coppe pipe, i mus be aken ca e ha he en i e leng h is in con ac wi h he
Figu e 1. Expe imen al se up a he speci ic loca ion.
A mul i-silicon glass panel wi h 1640 mm
×
992 mm
×
35 mm was pu chased o
cons uc a Pho o ol aic The mal Collec o . Because o he pla o m’s insula ing e ec , a
0.4 mm coppe shee was used o hea abso p ion on he back o he sola panel. Fu -
he mo e, he ex e nal and in e nal diame e s o he coppe ube a e 1.0 cm and 0.8 cm,
espec i ely, and a e placed o obse e hea behind he sola panel. Table 1shows he
pe o mance o he sola panel unde no mal es condi ions. The pho o ol aic he mal
sys em was o ien ed 13 deg ees sou h. E e y day, be ween 8 a.m. and 5 p.m., eadings o
all wea he condi ions and ou pu powe we e ob ained o i een minu es. A coppe ube
connec ed o a sola panel is shown in Figu e 2. This coppe ube is used because o high
hea conduc ion om he sola panel o he wa e which is passing h ough he pipe. When
placing he coppe pipe, i mus be aken ca e ha he en i e leng h is in con ac wi h he
sola panel, and a special a angemen using a clamp was used o make su e ha he pipe
is always in con ac wi h he sola panel.
To inc ease hea ansmission and educe ma e ial cos s, he nano luid was used
in he sola panel sys em. The single-phase me hod explains he hea conduc i i y and
p ope ies o nano luid TiO
2
. The basic assump ion o his echnique is he mal equilib ium
is main ained o nanopa icles and base luid, causing he suspension o beha e like
Ene gies 2022,15, 4425 4 o 12
a egula luid. The luid cha ac e is ics a e hen p esumed o ha e been al e ed as a
esul o he in oduc ion o nanopa icles. The essen ial pa o he single-phase me hod
unde hese assump ions is de e mining he e ec i e he mo-physical cha ac e is ics o
he nano luids. The e o e, he selec ion o compe en d i e s wi h easonable cos s ha
may be sold oge he is an essen ial conside a ion. Figu e 3shows he image o SEM o
TiO2nanopa icles.
Table 1. De ails o he sola panel.
Pa ame e Value Uni
Pmax 260 Wa s
Amps in Pmax 8.42 Amps
Vol s in Pmax 30.9 Vol s
Cu en in Maximum Load 8.89 Amps
Vol age in Maximum Load 37.7 Vol s
Weigh 18.2 Kilog am
Ene gies 2022, 15, x FOR PEER REVIEW 4 o 14
sola panel, and a special a angemen using a clamp was used o make su e ha he pipe
is always in con ac wi h he sola panel.
Figu e 2. Pho og aphic iew o he coppe ube along wi h he sola panel.
Table 1. De ails o he sola panel.
Pa ame e Value Uni
Pmax 260 Wa s
Amps in Pmax 8.42 Amps
Vol s in Pmax 30.9 Vol s
Cu en in Maximum Load 8.89 Amps
Vol age in Maximum Load 37.7 Vol s
Weigh 18.2 Kilog am
To inc ease hea ansmission and educe ma e ial cos s, he nano luid was used in
he sola panel sys em. The single-phase me hod explains he hea conduc i i y and p op-
e ies o nano luid TiO2. The basic assump ion o his echnique is he mal equilib ium is
main ained o nanopa icles and base luid, causing he suspension o beha e like a eg-
ula luid. The luid cha ac e is ics a e hen p esumed o ha e been al e ed as a esul o
he in oduc ion o nanopa icles. The essen ial pa o he single-phase me hod unde
hese assump ions is de e mining he e ec i e he mo-physical cha ac e is ics o he
nano luids. The e o e, he selec ion o compe en d i e s wi h easonable cos s ha may
be sold oge he is an essen ial conside a ion. Figu e 3 shows he image o SEM o TiO2
nanopa icles.
Figu e 2. Pho og aphic iew o he coppe ube along wi h he sola panel.
Ene gies 2022, 15, x FOR PEER REVIEW 5 o 14
Figu e 3. Pho og aphic iew o he coppe ube along wi h he sola panel.
3. Analy ical Me hodology
Elec ical and he mal ene gy analyses we e ca ied ou in his me hodology, which
a e de ailed below [30–34]. The go e ning di e en ial equa ion o he beha io o he
sys ems a e based on:
1. S eady-s a e ope a ion.
2. The inle mass low a e in o he sola he mal s o age ank is cons an .
3. The adia ion hea ans e is negligible.
4. The dus deposi ion on he sola panel is meage .
3.1. Pe o mance o Elec ical Ene gy
The a io o elec ical ene gy is elec ical powe , and he panel ene gy obse a ion
and equa ion a e gi en below.
 =


(1)

(2)
= 
(3)
3.2. Pe o mance o The mal Ene gy
The e iciency o he mal ene gy is employed o cha ac e ize he pe o mance o a
PV/T sys em.

ℎ
 =

(4)
=   =  (− )
(5)
 = 
(6)
These equa ions a e based on he sola adia ion alling on he pa icula a ea o he
sola panel being well de ined in he sola adia ion obse a ions. These obse a ions a e
known as . The mass low a e o coolan , hea ca ying capaci y o he coolan di e -
ence o inle , and he ou pu o he coolan a e combined, p oducing wha is known as
hea ene gy gene a ion .
3.3. Unce ain y Analysis
Figu e 3. Pho og aphic iew o he coppe ube along wi h he sola panel.
Ene gies 2022,15, 4425 5 o 12
3. Analy ical Me hodology
Elec ical and he mal ene gy analyses we e ca ied ou in his me hodology, which
a e de ailed below [
30
–
34
]. The go e ning di e en ial equa ion o he beha io o he
sys ems a e based on:
1. S eady-s a e ope a ion.
2. The inle mass low a e in o he sola he mal s o age ank is cons an .
3. The adia ion hea ans e is negligible.
4. The dus deposi ion on he sola panel is meage .
3.1. Pe o mance o Elec ical Ene gy
The a io o elec ical ene gy is elec ical powe , and he panel ene gy obse a ion and
equa ion a e gi en below.
ηelec =Pmax
.
Qs
(1)
Pmpmpmax (2)
.
Qs=Acol IG(3)
3.2. Pe o mance o The mal Ene gy
The e iciency o he mal ene gy is employed o cha ac e ize he pe o mance o a
PV/T sys em.
η he =
.
Qu
.
Qs
(4)
.
Qu=.
mCp∆T=.
mCp(To−Ti)(5)
.
m=ρAcolV(6)
These equa ions a e based on he sola adia ion alling on he pa icula a ea o he
sola panel being well de ined in he sola adia ion obse a ions. These obse a ions a e
known as
.
Qs
. The mass low a e o coolan , hea ca ying capaci y o he coolan di e ence
o inle , and he ou pu o he coolan a e combined, p oducing wha is known as hea
ene gy gene a ion .
Qu.
3.3. Unce ain y Analysis
The indi idual calib a ion dis o ion pa ame e s o he PVT collec o a e shown in
Table 2. Unce ain ies analysis is equi ed o con i m he accu acy o each expe imen al
se up. Da a ex ac ion mis akes, example calib a ion p oblems, da a p ocessing e o s, and
unique ins umen ambigui ies a e all examples o e o s. The majo i y o he inaccu acies
in his s udy we e p oduced by he o e es ima ion o each a iable, such as empe a u e,
sola i adia ion, s ess, and luid eloci y. The mos signi ican unce ain y in p edic ing
sola collec o e iciency is abou 3.6 pe cen (Table 3).
Table 2. Indi idual calib a ion dis o ion pa ame e s o he PVT collec o .
Senso Dis o ion Type
Ambien ai empe a u e ±0.2 ◦C K- he mocouple
Hea pipe empe a u e ±0.2 ◦C K- he mocouple
Ro ame e ±2.3% UKL
Sola powe me e ±4 W/m2TM-206
Inle & ou le empe a u e ±0.2 ◦C K- he mocouple
Da a logge ±3.4% Agilen 34980A

Ene gies 2022,15, 4425 6 o 12
Table 3. Pe cen age inc ease o he mal e iciency %.
Sl. No Wo king Fluid The mal E iciency (%)
A e age A Ex eme Sola Radia ion
1 0.5 LPM 25.76% 35.31%
2 1.0 LPM 29.88% 40.96%
3 0.05% TiO2wi h 0.5 LPM 36.32% 49.79%
4 0.05% TiO2wi h 1.0 LPM 40.70% 55.80%
4. Resul s and Discussion
Acco ding o he indings, he empe a u e g adien panels g ew h oughou he
day as sun i adia ion inc eased. The pa e n o ai empe a u e and sola adia ion is
simila ; howe e , he PV su ace emp/ adia ion ac o o PV panels is subs an ially mo e
signi ican han o cooled panels. Fu he mo e, he empe a u e di e en ial be ween he
cooling PV panel and he baseline panel d opped; o example, a midday, he di e ence
was 12.6
◦
C, bu a he end o he day, i was only 7.2
◦
C due o Nano luid obs uc ing he
cooling unc ion. This s udy also includes se e al o he pa ame ic es s de ailed below.
In Figu e 4, he sola adia ion in ensi y o chosen days was gi en o compa ison
as an example o a simila me ological s a e. E e y 15 s, he da a is collec ed and used
o u he analysis. The en i onmen al da a, sola in ensi y, and wea he condi ions om
he ini ial days we e ga he ed, which a e shown in Figu e 4. F om his g aph, he diu nal
a e age incoming sola adia ion dispe sion o e he expe imen pe iod is a whis le shape.
I was obse ed du ing he es ha he smalles alues we e 307.18 W/m
2
, eco ded on
mo ning 7, and 219 W/m
2
on e ening 5. The daily a e age ai empe a u e ises om 29.36
o 34.23 deg ees Celsius om 9 a.m. o 5:00 p.m.
Ene gies 2022, 15, x FOR PEER REVIEW 7 o 14
Figu e 4. A e age expe imen al day o he wea he in o ma ion a a speci ic loca ion.
The inciden sola adia ion on chosen days is depic ed in Figu e 5 a a ce ain poin
in he expe imen al esea ch in a sample o iden ical me ological si ua ions. Sola adia-
ion is an essen ial ac o in boos ing he pe o mance o bo h luids. The sola adia ion
and ambien empe a u e a he exac a ea displayed simila pa e ns h oughou he day.
Figu e 5. Th ee expe imen al es days o sola adia ion in W/m2.
The TiO2 nano luid u ilized had an ideal olume le el o 0.05 pe cen . Figu e 6
demons a es ends in elec ical e iciencies, such as ees anding PV, wo ypes o wa e
low a es, and TiO2 nano luid olume concen a ion. The sys em e iciency was inc eased
by 67.25 pe cen on a e age du ing he ial day when he op imal concen a ion o he
chosen Nano luid was used compa ed o he non-cooled module. The luc ua ion in sola
cell e iciency wi h espec o ime and ai mass low a e is demons a ed in Figu e 7. The
g aph demons a es ha he inc eased mass low a e in he PVT collec o esul s in lowe
cell empe a u e and g ea e cell e iciency.
0
200
400
600
800
1000
1200
7 8 9 10 11 12 13 14 15 16 17 18
Sola Radia ion (W/m2)
Time o he day (h s)
Exp. Tes Day 1 Exp. Tes Day 2
Figu e 4. A e age expe imen al day o he wea he in o ma ion a a speci ic loca ion.
The inciden sola adia ion on chosen days is depic ed in Figu e 5a a ce ain poin in
he expe imen al esea ch in a sample o iden ical me ological si ua ions. Sola adia ion
is an essen ial ac o in boos ing he pe o mance o bo h luids. The sola adia ion and
ambien empe a u e a he exac a ea displayed simila pa e ns h oughou he day.
Ene gies 2022,15, 4425 7 o 12
Ene gies 2022, 15, x FOR PEER REVIEW 7 o 14
Figu e 4. A e age expe imen al day o he wea he in o ma ion a a speci ic loca ion.
The inciden sola adia ion on chosen days is depic ed in Figu e 5 a a ce ain poin
in he expe imen al esea ch in a sample o iden ical me ological si ua ions. Sola adia-
ion is an essen ial ac o in boos ing he pe o mance o bo h luids. The sola adia ion
and ambien empe a u e a he exac a ea displayed simila pa e ns h oughou he day.
Figu e 5. Th ee expe imen al es days o sola adia ion in W/m2.
The TiO2 nano luid u ilized had an ideal olume le el o 0.05 pe cen . Figu e 6
demons a es ends in elec ical e iciencies, such as ees anding PV, wo ypes o wa e
low a es, and TiO2 nano luid olume concen a ion. The sys em e iciency was inc eased
by 67.25 pe cen on a e age du ing he ial day when he op imal concen a ion o he
chosen Nano luid was used compa ed o he non-cooled module. The luc ua ion in sola
cell e iciency wi h espec o ime and ai mass low a e is demons a ed in Figu e 7. The
g aph demons a es ha he inc eased mass low a e in he PVT collec o esul s in lowe
cell empe a u e and g ea e cell e iciency.
0
200
400
600
800
1000
1200
7 8 9 10 11 12 13 14 15 16 17 18
Sola Radia ion (W/m2)
Time o he day (h s)
Exp. Tes Day 1 Exp. Tes Day 2
Figu e 5. Th ee expe imen al es days o sola adia ion in W/m2.
The TiO
2
nano luid u ilized had an ideal olume le el o 0.05 pe cen . Figu e 6
demons a es ends in elec ical e iciencies, such as ees anding PV, wo ypes o wa e
low a es, and TiO
2
nano luid olume concen a ion. The sys em e iciency was inc eased
by 67.25 pe cen on a e age du ing he ial day when he op imal concen a ion o he
chosen Nano luid was used compa ed o he non-cooled module. The luc ua ion in sola
cell e iciency wi h espec o ime and ai mass low a e is demons a ed in Figu e 7. The
g aph demons a es ha he inc eased mass low a e in he PVT collec o esul s in lowe
cell empe a u e and g ea e cell e iciency.
Ene gies 2022, 15, x FOR PEER REVIEW 8 o 14
Figu e 6. E iciency o PV and PVT modules wi h wo king luids.
As illus a ed in Figu e 7, cooling de ices lowe ed he a e age empe a u es o PV
and PVT modules, whe he employing il e ed wa e o in oducing nano luid in o he
liquid. The empe a u e o he PV and PVT panels inc eased as he sola adia ion le els
inc eased du ing he day. E en hough he maximum su ace empe a u e o he modules
has ollowed he same ajec o y as he sola adia ion, he empe a u e o PV is signi i-
can ly g ea e o PV panels han o cooling panels. The PV panel and he egula panel
di e ence in empe a u e dec ease du ing he day. The empe a u e di e ence a midday
was 16 °C, and a he end o he day was 15 °C, because he hea s o ed in he Nano luid
began o ha e a e e se impac . The a e age empe a u e o he ial day, a ees anding
PV module, and he highes nano luid concen a ion wi h a high- olume low a e we e
51.3 °C and 38.8 °C, espec i ely.
Figu e 6. E iciency o PV and PVT modules wi h wo king luids.
As illus a ed in Figu e 7, cooling de ices lowe ed he a e age empe a u es o PV
and PVT modules, whe he employing il e ed wa e o in oducing nano luid in o he
liquid. The empe a u e o he PV and PVT panels inc eased as he sola adia ion le els
inc eased du ing he day. E en hough he maximum su ace empe a u e o he modules
Ene gies 2022,15, 4425 8 o 12
has ollowed he same ajec o y as he sola adia ion, he empe a u e o PV is signi ican ly
g ea e o PV panels han o cooling panels. The PV panel and he egula panel di e ence
in empe a u e dec ease du ing he day. The empe a u e di e ence a midday was 16
◦
C,
and a he end o he day was 15
◦
C, because he hea s o ed in he Nano luid began o
ha e a e e se impac . The a e age empe a u e o he ial day, a ees anding PV module,
and he highes nano luid concen a ion wi h a high- olume low a e we e 51.3
◦
C and
38.8 ◦C, espec i ely.
Ene gies 2022, 15, x FOR PEER REVIEW 9 o 14
Figu e 7. PV and PVT module empe a u e wi h di e en wo king luids.
Figu es 8 and 9 depic a ious wo king luids and hei elec ical e iciency and sun
adia ion in he mo ning and a e noon. Acco ding o he diag am, when sola adia ion
inc eases, elec ical pe o mance dec eases, which is especially impo an du ing he
on line and a e midday. Excessi e sunshine has a signi ican nega i e e ec on he
elec ical sola panels’ pe o mance. Sola adia ion is an excellen pa ame e o in luenc-
ing he elec ical p ope ies o wa e and wa e -nano luid mix u es.
Figu e 7. PV and PVT module empe a u e wi h di e en wo king luids.
Figu es 8and 9depic a ious wo king luids and hei elec ical e iciency and sun
adia ion in he mo ning and a e noon. Acco ding o he diag am, when sola adia ion
inc eases, elec ical pe o mance dec eases, which is especially impo an du ing he on -
line and a e midday. Excessi e sunshine has a signi ican nega i e e ec on he elec ical
sola panels’ pe o mance. Sola adia ion is an excellen pa ame e o in luencing he
elec ical p ope ies o wa e and wa e -nano luid mix u es.
Figu e 10 depic s he luc ua ion o inpu and ou pu luid empe a u es wi h a ying
olume low a es and concen a ions. The inle ai empe a u e linea ly ollowed he
ambien ai empe a u e. The a ia ion in
∆
T was caused by he di e en concen a ion and
olume low a es o he nano luids. In gene al, lowe a es o wa e and nano luid mixed
wi h wa e esul ed in he mos signi ican empe a u e changes, whe eas highe olume
low a es esul ed in he smalles . Acco ding o he ollowing g aphic, an 11.8
◦
C di e ence
was achie ed a a wa e low a e o 0.5 LPM a noon. As a esul , a 13.3
◦
C di e ence was
ob ained a 0 LPM on he es ing day’s midday. Fu he mo e, a ound midday on he ial
day, a di e ence o 12.5 ◦C was achie ed wi h wa e mixed wi h a nano luid o 0.5 LPM.
A e ha , a midday on he ial day, a di e ence o 9.3 TiO
2
manganese oxide.
The PVT collec o was es ed a wo di e en olume concen a ions, 0.5 and 1.0 Li e s
pe minu e (LPM). The highes he mal e iciency o he sys em was de e mined o be
48.38 pe cen and 54.03 pe cen , espec i ely, a he olumes o 0.5 LPM and 1.0 LPM. The
highes elec ical e iciency o he PV/T collec o was de e mined o be 18.32 pe cen and
19.35 pe cen , espec i ely, o 0.5 LPM and 1.0 LPM o olume low a es. The esul s
demons a e ha nano luid has mo e excellen he mal conduc i i y han a base luid wi h a
li le inc ease in iscosi y and luid densi y. I was achie ed in wa e mixed wi h nano 1.0 LPM.
Ene gies 2022,15, 4425 9 o 12
Ene gies 2022, 15, x FOR PEER REVIEW 9 o 14
Figu e 7. PV and PVT module empe a u e wi h di e en wo king luids.
Figu es 8 and 9 depic a ious wo king luids and hei elec ical e iciency and sun
adia ion in he mo ning and a e noon. Acco ding o he diag am, when sola adia ion
inc eases, elec ical pe o mance dec eases, which is especially impo an du ing he
on line and a e midday. Excessi e sunshine has a signi ican nega i e e ec on he
elec ical sola panels’ pe o mance. Sola adia ion is an excellen pa ame e o in luenc-
ing he elec ical p ope ies o wa e and wa e -nano luid mix u es.
Figu e 8.
Va ious wo king luids and hei elec ical e iciency and sola adia ion du ing he o enoon
o he day.
Ene gies 2022, 15, x FOR PEER REVIEW 10 o 14
Figu e 8. Va ious wo king luids and hei elec ical e iciency and sola adia ion du ing he o e-
noon o he day.
Figu e 9. Va ious wo king luids and hei elec ical e iciency and sola adia ion du ing he a e -
noon o he day.
Figu e 10 depic s he luc ua ion o inpu and ou pu luid empe a u es wi h a ying
olume low a es and concen a ions. The inle ai empe a u e linea ly ollowed he am-
bien ai empe a u e. The a ia ion in ΔT was caused by he di e en concen a ion and
olume low a es o he nano luids. In gene al, lowe a es o wa e and nano luid mixed
wi h wa e esul ed in he mos signi ican empe a u e changes, whe eas highe olume
low a es esul ed in he smalles . Acco ding o he ollowing g aphic, an 11.8 °C di e -
ence was achie ed a a wa e low a e o 0.5 LPM a noon. As a esul , a 13.3 °C di e ence
was ob ained a 0 LPM on he es ing day’s midday. Fu he mo e, a ound midday on he
ial day, a di e ence o 12.5 °C was achie ed wi h wa e mixed wi h a nano luid o 0.5
LPM.
Figu e 9.
Va ious wo king luids and hei elec ical e iciency and sola adia ion du ing he
a e noon o he day.
Figu e 11 depic s a PVT module he mal e iciency wi h a ious wo king luids.
Equa ions (4)–(6) a e used o assess mul iple equa ions o ge he hyb id collec o he mal
e iciency. I is es ima ed using quan i iable c i e ia such as he empe a u e di e en ial
be ween he exi and in ake ai , ai mass low a e, ai -speci ic hea , sola panel a ea,
and sola adia ion. When he low a e changes om 0.5 LPM o 1.0 LPM, he he mal