The research paper published by IJSER journal is about Effects of Some Meteorological Variables on the Performance of Single Slope Solar Stills in Sokoto, North Western Nigeria 1

ISSN 2229-5518

Effects of Some Meteorological Variables on the Performance of Single Slope Solar Stills in Sokoto, North Western Nigeria

Kaisan Muhammad Usman and Sabi’u Bala Muhammad

Abstract- In this res earc h, water s ample was c ollec ted from Kwalkwalawa river, in Kwalk walawa village, Sokoto State, North W estern Nigeria. 25L of the water s amlpe was us ed to f ill a sinlge s lope s olar s till, and the wh ole s et up expos ed to the s olar en ergy. T he distillate yi elds of the s am ple were r ec orded at one h our intervals between the hours of 8.00am and 18.00pm. T he c orres ponding values were meas ured f or s ome m eteorologic al variables like: s olar radiation, ambient temp erature, rel ative humidity and wind s peed during each inerval. The res ults were tabulated and pic turesque us ing bar ch arts. It was ober ved that the maximum yield rec orded was obtained by

15.00pm. whic h als o c orres ponds to the highies t value of wind s peed whic h acc ounts f or c ondens ation of the

evap orated dis tillate. The relative humidity varied invers ely with the yi eld. It has been obs erved that s ol ar radiation varies parab olic ally with time, with its maximum value at 13.00pm. Sol ar radiation als o varies linearly with yield onl y that, radiation reac hed its peak at around 13.00pm while the yield reac hed its maximum valu e aro und 15.00pm. Finally the yi eld of the dist illed water incres ed as the ambient temperature inc reas ed, with the maximum yi eld rec orded at the maximum valu e of the ambient temperature ie at 15.00pm. W hen the ambient temper ature started to dec line, the yield als o started to dec line equally.

Index Terms— Ambient temperature, relati ve humidity, s ol ar radiation, s olar still, wind s peed

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1 INTRODUCTION

Solar distillation is a process by which impure water is heatedwith solar energy, the evaporated water vapor is trapped and the condensed distillate collected as pure water (Garba et al,
20005). It is estimated that over two billion people are not connected to a power grid and will not be in the near future for a reason related to seclusion, low population density, poverty and inaccessibilty. For these reasons, and to these people, autonomous solar systems can play a very important role in lighting, pumping, heating, drying etc (Alkama and Arkoub, 2009).

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Engr. Kaisan Muhammad Usman is a Scientific Officer with Energy

Commission of Nigeria, Abuja, Nigeria, PH-+2348036943404. E-mail:

The use of solar distillation method in water purification is a very important method of solving day to day need of isolated villages for clean and healthy water. Distilled water is used for for different purposes in institutions for laborotory experiments, health care centers, motor vehicle batteries, industrial and in commercial organisations (Garba et al, 2005).
Furthermore, the sun supplies morethan enough energy to the entire system, its energy is replenishable, or in another term renewable. About 1.7 X 1017 watts per second of solar radiation is incident upon the earth. This is 30,
000 times the global energy use by human beings
(Garba et al, 2005). The solar distillatiion process is depended on different meteorological
engineer.kaisan@gmail.com

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Sabi’u Bala Muhammad is a Lecturer with Department of Physics, Usmanu Danfodio Universtity Sokoto, Nigeria and an M.Sc. Candidate with Same University, PH-+2348030683492 E-mail: sbala02@yahoo.com

The research paper published by IJSER journal is about Effects of Some Meteorological Variables on the Performance of Single Slope Solar Stills in Sokoto, North Western Nigeria 2

ISSN 2229-5518

parameters, such as weather parameters like ambient air temperature, relative humidity, solar radiation and wind speed. This research work investigated the performance these meteorological variables on the distillate yield of solar still with time.
More so, clean water is an essential requisite for humankind and other living things to maintain their daily life. In many parts of the globe, fresh water demand of the people is fundamentally rising and this demand cannot be met by the obtainable natural water supply, in view of the fact that existing water sources are becoming limited and scarce, and also, they are being contaminated gradually with the large quantity of sewage and industrial waste. Conversely, abundant of solar energy is accessible with the large amount of rivers, lakes, sea water etc. Therefore, it is feasible to produce clean water from such water bodies using solar energy (i.e., solar destillation) economically. Consequently, increasing of clean and healthy water demand of the people can be solved partially by using solar destillation technologies (Yamali and Solmus,
2008).
According to Suleiman and Tarawneh (2007) major parameters which influence the solar still performance such as: dry spots and scale formation, air-tight conditions, glass cover inclination were investigated by different researchers; and good results were published (Boukar et al, 2004, Anil etal, 2005, El-Sebaii etal,
2005 and Aybar etal, 2005). The major handicaps that negatively influence the solar still productivity were taken in consideration, and some improvements on the design and operational conditions were made. In this reserch
work however, the variation of some meteorological variables such as ambient temperature, relative humidity, wind speed and solar radiation on the solar still were investigated.

2 METHODOLOGIES

A single slope insulated solar still was filled with
25L of water sample from Kwalkwalawa River, Sokoto State, North Wwestern Nigeria. The Kwalkwalaw river is the main source of water for drinking, cooking and other domestic and agricultural functions in the Kwalkwalawa village. However, during the previous reseach by same authors, it was observed that the water from such source has some contaminations and as such not healthy, and whence, the need for application of solar still distillation. The distillate output of the water sample was observed on hourly basis, between the hours of 8.00am. and
18.00pm.
Furthermore, at each hour interval, the solar radiation was measured using Pyranometer (Hioki 2005No. 951124222); the ambient temperature was measured using Digital Thermometer; the Wind speeds were measured using Anemometer and the relative humidities were measured using Hygrometer correspondingly. The results were tabulated in table 1 below, and analyses were carried out on the results.

3 RESULTS AND DISCUSSIONS

The experimental results of the effects of some meteorological variables: Solar radiation, ambient temperature, relative humidity and wind speed with distillte yields on hourly basis
were tabulated in table 1 below.

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The research paper published by IJSER journal is about Effects of Some Meteorological Variables on the Performance of Single Slope Solar Stills in Sokoto, North Western Nigeria 3

ISSN 2229-5518

TABLE 1

EXPERIMENTAL RESULTS

Time

Interv al

(hour)

Solar

Radiation

(W /m2)

Ambient

Temperature

(0C)

Relativ e

Humidity

(%)

Wind Speed

(m/s)

Yields in

(ml)

8.00

260

23.30

15.20

0.4

0.40

9.00

455

35.00

3.70

1.3

16.70

10.00

650

41.50

2.60

1.5

35.00

11.00

780

43.30

1.20

0.5

50.00

12.00

858

43.00

0.45

1.7

120.00

13.00

871

43.40

0.00

0.6

170.00

14.00

793

45.20

0.00

2.0

190.00

15.00

624

43.50

0.30

6.0

210.00

16.00

338

38.70

2.70

0.9

140.00

17.00

143

32.70

6.00

0.5

100.00

18.00

13

27.10

11.60

0.0

0.40

3.1 Solar Radiation

It has been observed that solar radiation varies parabolically with time, with its maximum value at 13.00pm. Solar radiation also varies linearly with yield only that, radiation reached its peak at around 13.00pm while the yield reached its maximum value around 15.00pm
. Between the hours of 13.00 and 15.00,although the solar radiation had started declining, the yield was still incresing for the two hour interval. This iwas because, the solar still has trapped enough energy from the solar radiation, so that
the water temperature increased significantly to
achieve maximum everporation and condensation, and ofcause the yield.

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The research paper published by IJSER journal is about Effects of Some Meteorological Variables on the Performance of Single Slope Solar Stills in Sokoto, North Western Nigeria 4

ISSN 2229-5518



Figure 1 Variation of Solar Radiation with
Distillate Yields

3.2 Ambient Temperature

From the experimental result and figure 2 below, the yield of the distlled water incresed as the ambient temperature increased, with the maximum yield recorded at the maximum value of the ambient temperature ie at 15.00pm. When the ambient temperature started to decline,the yield also started to decline correspondingly. This was because, at higher values of the ambient temperature (afternoon), heat lost by the water content of the solar still due to conduction and convention was thereby reduced. At minimum values of the ambient temperature (Morning and Evening), more heat was lost from the single slope solar still to the surrounding, this is because, conduction rate is always proportional to the temperature gradient.
Figure 2 Variation of Ambient Temperature with
Distillate Yields

3.3 Relative Humidity

Relative humidity as the only opposing parameter which can be observed from the experimental result and figure 3 below, had negative effect on the yield performance of single slope solar still. It was categorically clear that, minimum yield was recorded at maximum values of the relative humidity (During the hours of 8.00am and 18.00pm). Moreso, maximum yield was recorded at the minimum values of relative humidity (During the hours of 13.00pm and 15.00pm).

Figure 3 Variation of Relative Humidity with
Distillate Yields

3.4 Wind Speed

From the experimental result and the figure 4 below, wind speed fluctuated at each hour
reaching its peak at 15.00pm. corresponding to

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The research paper published by IJSER journal is about Effects of Some Meteorological Variables on the Performance of Single Slope Solar Stills in Sokoto, North Western Nigeria 5

ISSN 2229-5518

the maximum yield, after which it began to decline. This shows that, more water vapour in the solar still was forced to condense for maximum yield to be achieved at higher values of wind speed. At lower speeds however, eventhough enough water vapourwas formed less condensation and (ofcause) yield was recorded. This is because,wind speed may be the only agent of cooling.

Figure 4 Variation of Wind Speed with Distillate
Yields

4 CONCLUSIONS

Conclusively, going by the experimental findings presented abinitio, the solar radiation, the ambienttemperature and the wind speed increase with a corresponding increase in distillate yield. While the relative humidity decreases with a corresonding increase in distillate yield. Hence, all the meteorological variables herein observed, have effects on the yield performance of single slope solar still withtime.

REFERENCES

[1] Suleiman M. and Tarawneh K (2007). Effect of Water Depth on the Performance Evaluation of Solar Still, Jordan Journal of Mechanical and Industrial Engineering, Volume 1, Number 1,

Sep. 2007 ISSN 1995-6665. Pages 23 – 29

[2] Garba B. Musa M. and Atiku A. T (2005). Studies on the Chemical Composition of the Distillate Yield from Solar Distillation System. Nigerian Journal of Solar Energy. Vol. 15. PP

150-155

[3] Alkama R. and Arkoub M (2009).Solar house and weather factors in Bejaia city (Algeria). Electro Technical Department. Faculty of Technology in Bejaia University, Algeria. PP 1-4

[4] Yamale C. and Solmus I (2008). A solar desalination system using humidification–dehumidification process: experimental study and comparison with the theoretical results. Presented at the Conference on Desalination and the Environment. Sponsored by the European Desalination Society and Center for Research and Technology Hellas (CERTH), Sani Resort, Halkidiki, Greece, April 22–25, 2007. PP 538-551

[5] Boukar M. and Harmim A (2004). Parametric Study of a vertical solar still under desert climatic conditions, Desalination, Vol.168. PP 21-28

[6] Anil K. and Tiwari G. N (2005). Effect of the condensing cover’s slope on internal heat and mass transfer in distillation: an indoor simulation, Desalination. Vol.180, PP 73-88

[7] El-Sebaii A. A (2005). Thermal performance of a triple-solar still, Desalination, vol.174, PP 23-37.

[8] Aybar H. S., Egelioglu F. and Atikol U (2005). An experimental study on an inclined solar distillation system, Desalination. Vol.180, PP 285-289.

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