Download - PRESENTATION SEEP
AN INVESTIGATIONON THE PERFORMANCES OF SOLARDOMESTIC HOT WATER SYSTEMS IN
TURKISH REPUPLIC OF NORTHERN CYPRUS
Presented by:
YOUSSEF YAHYA OSMANDone by:Assit. Prof. Dr. ALİ EVCİL
YOUSSEF YAHYA OSMAN
CONTENTS
INTRODUCTION AIM METHODOLOGY
RADIATION ON HORIZONTAL SURFACE
RADIATION ON SOLAR COLLECTORS
SDHWS LAPORATORY TESTS SDHWS ON-SITE TESTS
RESULT AND DISCCUSIONSolar Radiation for Nicosia in 2007
RADIATION ON SOLAR COLLECTORS
LAPORATORY TESTSON-SITE TESTS
CONCLUSIONS RECOMMENDATIONS
INTRODUCTION
Cyprus is located at the eastern part of Mediterranean Sea
Sunny days are about 340 days per year Yearly average global radiation is 1727 Thermosyphon type SDHWS are used commonly The question is “How efficient SDHWS are in use in
TRNC?”
Solar Domestic Hot Water System (SDHWS)
INTRODUCTIONCyprus Solar Energy map
INTRODUCTION
System consists of:• Storage cylinder• Solar collectors
24 Galvanized pipes Glass cover Insulation
• Connecting pipes
Thermosyphonic System
AIM
The aim of the study is• To investigate the effect of collector tilt and
azimuth angles on the performance of SDHWS theoretically and also experimentally
• To investigate the performances of SDHWS in use in TRNC
METHODOLOGY
Hourly variation of solar radiation on a horizontal surface (Qmet) in Nicosia for the year 2007 and also for the dates of experiments conducted were obtained from meteorological office of TRNC.
Radiation on Horizontal Surface
By adding the hourly radiation data the daily total radiation were obtained.
By averaging the total daily radiation per month of the year to calculate the monthly average values for SDHWS applications.
Radiation on Solar Collectors
• Declination angle
• Hour angle
𝛿=23 . 45 ° 𝑠𝑖𝑛[𝑁+284365
×360 ° ]
𝐻=(𝑚𝑖𝑛𝑢𝑡𝑒𝑠𝑝𝑎𝑠𝑡𝑚𝑖𝑑𝑛𝑖𝑔h 𝑡−720𝑚𝑖𝑛 )
4𝑑𝑒𝑔/𝑚𝑖𝑛
Radiation on Solar Collectors
• Solar azimuth angle
• Altitude angle
• Zenith angle
cos𝛼1=sin 𝛽1 sin (𝐿) sin (𝛿 )
cos 𝛽1cos (𝐿)
sin ¿¿
cos (𝜃𝑧 )=cos (𝐿) cos ( δ ) cos (𝐻 )+sin (𝐿 )¿¿
Radiation on Solar Collectors
• Incidence angle
=
LABORATORY TESTS Laboratory tests done with a range of tilt and azimuth angles were
considered Six T-type thermocouples (T1 to T6) used to record the temperature
variation Data acquisition system (ORDEL UDL100)
Procedure:1. Adjust the tilt and collector azimuth angles.2. Refill the system with cold water.3. Start the measurements removing the cover of solar panels.4. Stop the experiment after enough data is collected.5. Plot the results against time.
ON-SITE TESTS 2 T-Type thermocouples used to measure the top and button
temperature variation of HWC Data acquisition system (ORDEL UDL100)
Procedure:1. Record the variables on the case study paper (Date, Tilt angle, Collector azimuth, Area of collector, Volume of HWC)2. Make the connections before sun rise.3. Record temperature variations from sunrise to sunset.4. Calculate energy absorbed by assuming linear variation of temperature5. Plot the results against time.
RESULTS AND DISCUSSION
Solar Radiation for Nicosia in 2007
Daily Solar Radiation (Nicosia, 2007) Monthly Average Daily Solar Radiation (Nicosia, 2007)
Radiation on Solar Collectors Tilt Angle Variation
Autumn Equinox
• Tilt angle below and above 36° the radiation on the collector surface increases
0
500
1000
1500
2000
2500
3000
3500
4000
02 04 06 08 10 12 14 16 18
GMT
Sola
r Rad
iatio
n (k
J/hm
2 )
0°
12°
24° 48°
36°
60°
Autumn EquinoxSept. 23rd, 2007
Nicosia
Radiation on Solar Collectors Azimuth Angle variation
Winter Solstice
• The change in azimuth angle towards east and west will cause more energy gain in the morning and afternoon, respectively.
• Performance decreases
48°
0
500
1000
1500
2000
2500
3000
3500
4000
02 04 06 08 10 12 14 16 18
GMT
Sola
r Rad
iatio
n (k
J/hm
2 )
Winter SolsticeDec. 21st, 2007
Nicosia
Sou
th
Qmet
20°E
60°E 60°W
20°W
Radiation on Solar Collectors
• The installation of the system may cause efficiency drops well below the lowest efficiency value of 30% down to 10%
0
500
1000
1500
2000
2500
3000
3500
02 04 06 08 10 12 14 16 18
GMT
Ther
mal
Ene
rgy
(kJ/
hm2 )
10%
Aug. 8th, 2007NicosiaTilt: 36°
Azimuth: 0°
20%
30%
40%
50%
60%
70%
80%
90%
Qmet
100%
Radiation on Solar Collectors
• for the equinoxes the best tilt angle seems to be 36 which makes half of the year needs this angle and as the study shows that for the summer and winter time the average tilt angle is also 36 degrees where also at this angle the performance is stable.
-40
-30
-20
-10
0
10
20
30
0 12 24 36 48 60 72Tilt Angle (Degrees)
Chan
ge o
f Per
form
ance
(%)
Summer Solstice Autumn Equinox Winter Solstice
Radiation on Solar Collectors
• Azimuth angle directed to the south gives the equinoxes and solstices a stable performance
LABORATORY TEST RESULTS Gradual increase in
temperature Decrease in the
temperature difference between the upper and lower parts of the HWC shows that the SDHWS has nearly reached to its maximum capacity of heating.
LABORATORY TEST RESULTS The variation of
temperature in the vertical direction within the HWC (nearly linear)
LABORATORY TEST RESULTS
0
500
1000
1500
2000
2500
3000
3500
4000
02 04 06 08 10 12 14 16 18GMT
Rad
iatio
n / T
h. E
nerg
y (k
J/hm
2 ) Aug. 24th, 2015Nicosia
Col. Tilt: 36°Azimuth: 40°E
30%
15%
Qmet
Qcol
0
500
1000
1500
2000
2500
3000
3500
4000
02 04 06 08 10 12 14 16 18GMT
Rad
iatio
n / T
h. E
nerg
y (k
J/hm
2 ) Aug. 27th, 2015Nicosia
Col. Tilt: 48°Azimuth: 40°E
30%
15%
Qmet
Qcol
LABORATORY TEST RESULTS
0
500
1000
1500
2000
2500
3000
3500
4000
02 04 06 08 10 12 14 16 18GMT
Radi
atio
n / T
h. E
nerg
y (k
J/hm
2) Aug. 18th, 2015
NicosiaCol. Tilt: 36°
Azimuth: South
30%
15%
Qmet
Qcol
0
500
1000
1500
2000
2500
3000
3500
4000
02 04 06 08 10 12 14 16 18GMT
Rad
iatio
n / T
h. E
nerg
y (k
J/hm
2 ) Sept. 17th, 2015Nicosia
Col. Tilt: 48°Azimuth: South
30%
15%
Qmet
Qcol
LABORATORY TEST RESULTS
0
500
1000
1500
2000
2500
3000
3500
4000
02 04 06 08 10 12 14 16 18GMT
Rad
iatio
n / T
h. E
nerg
y (k
J/hm
2) Aug. 21st, 2015
NicosiaCol. Tilt: 36°
Azimuth: 40°W
30%
15%
Qmet
Qcol
0
500
1000
1500
2000
2500
3000
3500
4000
02 04 06 08 10 12 14 16 18GMT
Rad
iatio
n / T
h. E
nerg
y (k
J/hm
2 ) Sept. 15th, 2015Nicosia
Col. Tilt: 48°Azimuth: 40°W
30%
15%
Qmet
Qcol
On-site Experiments Results
0
500
1000
1500
2000
2500
3000
3500
4000
02 04 06 08 10 12 14 16 18GMT
Rad
iatio
n / T
h. E
nerg
y (k
J/hm
2)
0
10
20
30
40
50
60
70
80
Tem
pera
ture
(°C
)
Aug. 1st, 2015Nicosia
Col. Tilt: 43°Azimuth: 40°E
30%
15%
Qcol
T1
T2
● Th. Energy
0
500
1000
1500
2000
2500
3000
3500
4000
02 04 06 08 10 12 14 16 18GMT
Rad
iatio
n / T
h. E
nerg
y (k
J/hm
2)
0
10
20
30
40
50
60
70
Tem
pera
ture
(°C)
Aug. 4th, 2015Nicosia
Col. Tilt: 35°Azimuth: 50°E
30%
15%
Qcol
T1
T2
● Th. Energy
On-site Experiments Results
0
500
1000
1500
2000
2500
3000
3500
4000
02 04 06 08 10 12 14 16 18GMT
Rad
iatio
n / T
h. E
nerg
y (k
J/hm
2 )
0
10
20
30
40
50
60
70
Tem
pera
ture
(°C
)
Aug. 30th, 2015Nicosia
Col. Tilt: 42°Azimuth: South
30%
15%
Qcol
T1T2
● Th. Energy
CONCLUSIONS Collector Azimuth Angle
Effects the energy absorption More in morning towards east More in afternoon towards west Summer performance not effected due to longer
day time In winter, spring and autumn lower performance
due to shorter day time Collector Tilt Angle
Autumn and spring: 36 °
Summer: < 36 °
Winter: > 36 °
Laboratory Experiments HWC water temperature increases gradually
At the beginning of the experiment ∆T is about 6 to 7°C.
At the end of the experiment ∆T is about 2 to 3°C.
As the temperature difference becomes less the energy absorption also becomes less.
The temperature profile was almost linear except at the beginning of heating and after hot water usage.
Efficiency is between 25 to 30% On-Site Experiments
Efficiency is between 15 to 25% 30% not working at all
RECOMMENDATIONS
Much more care must be taken during the installation of the systems and also for maintenance to obtain the most out of solar energy.
To obtain a most effective collector tilt angle for a SDHWS one must use seasonal domestic hot water requirements together with the seasonal performances, and can be considered as a future work.
THEORETICAL STUDYMicrosoft Excel Worksheet
THANK YOU FOR LISTENING