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SOLAR HOUSE AND WEATHER FACTORS IN BEJAIA CITY_ALGERIA

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SOLAR HOUSE AND WEATHER FACTORS IN BEJAIA CITY_ALGERIA Powered By Docstoc
					 International Journal of Electrical Engineering and Technology (IJEET), ISSN ENGINEERING
INTERNATIONAL JOURNAL OF ELECTRICAL0976 – 6545(Print), ISSN
 0976 – 6553(Online) Volume 3,& TECHNOLOGY (IJEET)
                                Issue 3, October – December (2012), © IAEME

ISSN 0976 – 6545(Print)
ISSN 0976 – 6553(Online)
Volume 3, Issue 3, October - December (2012), pp. 72-79                      IJEET
© IAEME: www.iaeme.com/ijeet.asp
Journal Impact Factor (2012): 3.2031 (Calculated by GISI)                 ©IAEME
www.jifactor.com




           SOLAR HOUSE AND WEATHER FACTORS IN BEJAIA CITY,
                             ALGERIA

                                   M. Arkoub*, R. Alkama*

                             *Laboratory of Electrical Engineering,
                         Faculty of technologies, University of Bejaia (Algeria)
                                       arkoub_m@yahoo.fr


  ABSTRACT

  In this paper, an autonomous solar house installation is presented. The power supply is
  exclusively in direct current (DC) which can respond to all needs and commodity of the
  house. The total cost of the sized system (panels, batteries and regulator) does not exceed
  4500 $. The meteorological parameters effects are investigated. Measurement results show
  that illumination and solar panel efficiency increase with ambient temperature and
  atmospheric pressure and decrease with relative humidity and wind speed. These variations
  are explained. A global radiation model including meteorological factors is established. A
  comparison between calculated and measured values of radiation gives a mean relative
  deviation of 26.81 %.

  Key words: photovoltaic energy, solar house, weather factors, Béjaia


  1. INTRODUCTION

  The growth of demand for energy by populations and the limited access to classic resources
  make that solar energy is expected to play an important role in energy demands, providing
  real economic and environmental solutions. It was estimated that more than two billion
  people in the world are not connected to a power grid. The reasons are poverty, remoteness,
  low population density or lack of need. For these people, autonomous solar systems represent
  the solutions for their needs (lighting, pumping, etc ....).
  Powering a house with solar energy would require the production and the storage of
  electricity for lighting, household appliances and water pumping. Heating is provided by a
  solar thermal collector that is beyond the scope of this study. The selection and sizing of the


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International Journal of Electrical Engineering and Technology (IJEET), ISSN 0976 – 6545(Print), ISSN
0976 – 6553(Online) Volume 3, Issue 3, October – December (2012), © IAEME


different components of the solar system must take into account the needs and the economic
aspect.
The amount of light captured by solar panels depends inevitably on weather conditions
(ambient temperature, relative humidity, atmospheric pressure, wind speed and direction) [1],
[2]. It is interesting to calculate the correlation coefficients with radiation and to try to find a
variation model.

2. HOUSE ENERGY REQUIREMENTS

The chosen house to be powered with the photovoltaic system is of type F3 in Algerian
Standard (2 rooms, a living room, kitchen, toilet and bathroom). Its surface is about 85 m².
The used appliances correspond to a minimum of comfort like lighting, water supply,
refrigeration and audio visual entertainment. The following table gives the appliances, their
power and their operating times.
Load (all DC)            Power (W)               Operating time(hour)           Energy/day (Wh/day)
7 lamps                  7*10=70                     04                                  280
Refrigerator                -                          -                                 600
2 fans                   2*50=100                    04                                  400
TV/HiFi                  50                          06                                  300
Pump                     80                           04                                  320
Total                                                                                   1.900
Table1: Energy requirements of an autonomous house.

Seven economic lighting lamps of 10 Watt power each one are necessary. Refrigerators or
freezers solar-type 12V or 24V with a volume close to 100 litres consume about 600 Wh /
day. The audiovisual equipment (television, demodulator, Hi-Fi system) type 12 V consumes
50 W with an average use of 6 hours. The most used pumping system works with a flow
which is proportional to the received light energy. The pumped water during the day is stored
in a tank for its use in the night. With an average total lift of about 20 m in Bejaia province
and a consumption of 4 m3 per day, the calculations give us a 80 W power pump. Two fans
are included for the summer time. Taking into account the powers of the components
supplied with direct current (DC) and the use time, we get a daily consumption of Ed=900
Wh / day.
The area of the photovoltaic panels can be calculated using the formula (1) [3]
                                       =                    (1)

   = 12% is the PV panel efficiency
  = 0.85 is the batteries efficiency
  = 0.8 is the temperature correction factor
H is the average solar radiation.

In the Bejaia case (with latitude north 36°45’ and longitude east 05°05’) the NASA surface
meteorology and solar energy tables give an average of 4.67 kWh/m²/day. [4]
The found area is       = 4.986 ²
That means that the required number of the panels available locally (TE1300, 125Wp, 17.9V,
150x68 cm²) is 5.
With a solar peak intensity of 1000 W/m², the generator peak power is:


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International Journal of Electrical Engineering and Technology (IJEET), ISSN 0976 – 6545(Print), ISSN
0976 – 6553(Online) Volume 3, Issue 3, October – December (2012), © IAEME


                      = Panels number * panels area * peak intensity *
                          = ∗ .         ∗ .     ∗       ∗ .      =
 Six batteries (12, 110 Ah) are necessary for a three days autonomy.
The total cost of panels, batteries and regulator does not exceed 4500 $.
The use of an inverter for powering AC-components will increase highly this cost. For
heating and hot water uses, a solar thermal collector of 50 litres is sufficient.

3. MEASUREMENTS NETWORK

For the experiment we used a solar panel (TE1300, 125 Wp, 17.9 V) connected to a charge
giving an optimum efficiency. The illumination is measured with a solar sensor of 30 cm2
surface fixed near the panel with the same inclination. Radiations, current ant voltage
delivered by the solar panel are recorded using a data acquisition system connected to a
personal computer.
Using a weather station Oregon Scientific, we recorded the meteorological parameters
(ambient temperature, relative humidity, atmospheric pressure, rainfall, wind speed and wind
direction). The samples are done each 10 minutes during twelve months (January-December
2009). In figure 1 is illustrated the measurements network.



                 Solar     U                   Data
                 panel     I                   acquisition


                 Solar sensor

                 Temperature T
                                                                   PC
                 Relative Humidity
                                            Weather
                 Pression                   station
                 Wind speed                 OREGON
                 Wind direction             SCIENTIFIC
                 Rain


                                     Fig 1: Measurements network

As shown in Figure 2, the sun can vary significantly between two successive days: April 29, a
cloudy and very disturbed day and April 30 a beautiful day.




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International Journal of Electrical Engineering and Technology (IJEET), ISSN 0976 – 6545(Print), ISSN
0976 – 6553(Online) Volume 3, Issue 3, October – December (2012), © IAEME




The current delivered by solar panels is proportional to the illumination. The calculated
                               956.
correlation factor is 0.956. The voltage varies less with the radiation.
In Figure 3 is represented the power generated by the solar panel versus the illumination. It is
closely related to the illumination. The correlation factor obtained is 0.871.




                    Fig 3: Power generated by the panel versus illumination


4. METEOROLOGICAL FACTORS

        The weather station Oregon Scientific that we used save six parameters (ambient
temperature, relative humidity, atmospheric pressure, rainfall, wind speed and wind
direction). Results are used to compare variations of each parameter and correlation with
measured illumination.
                                                                                        12
Figure 4 shows the average monthly variations of temperature and relative humidity over 1
          January              2009).
months (January to December 2009 Ambient temperature T varies from 3 °C to 46 °C and
          umidity                        89     hey
relative humidity (RH) varies from 8% to 8 %. They vary in opposite directions.




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International Journal of Electrical Engineering and Technology (IJEET), ISSN 0976 – 6545(Print), ISSN
0976 – 6553(Online) Volume 3, Issue 3, October – December (2012), © IAEME




Fig. 4 : Ambient temperature and relative humidity variations from during2009.


In figure 5 are represented the variation of atmospheric pressure P and the wind speed WS
during the same period.




                     Fig. 5 : Atmospheric pressure variations during 2009

Atmospheric pressure varies from 998.8 to 1013.9 millibars.

The regression analysis between the illumination and the various meteorological parameters
gave the following correlation coefficients:


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International Journal of Electrical Engineering and Technology (IJEET), ISSN 0976 – 6545(Print), ISSN
0976 – 6553(Online) Volume 3, Issue 3, October – December (2012), © IAEME


Illumination - temperature: R = +0.66
Illumination - Relative humidity R = -0.64
Illumination - pressure R = +0.79
Illumination - wind speed R = -0.34

Generally the ambient temperature increase is related to a good sunshine except some days
when dust wind from the Sahara is present. This case and the deposit on panel will be studied
in the near future.
When the weather is sunny, the atmospheric pressure is strong. When there's a depression,
there is arrival of clouds and the illumination decreases.
The humidity is made up of water vapour which diffracts and reflects sunlight and reduces
the sun [5]. So with increase of relative humidity we remark a decrease of illumination.

Bejaia is a coastal city; the wind gets up each afternoon and evening. Its direction is North
West with an angle of approximately 110 degrees from the reference direction of south. The
correlation is negative because the wind brings the vehicle and industrial pollution of the city
[4] and increases radiation diffracts and attenuation. Wind speed can be used to make an
hybrid photovoltaic - wind system. It will be very effective [7] because the wind happens
when the sun goes away.
Illumination correlations with rain and wind direction are not presented because obtained data
are not sufficient.

5. VARIATION MODEL

The basic model of Angstrom [8] is given as (2):
    = +           (2)
where H is the monthly average global daily radiation on horizontal surface, H0 is the
monthly average daily extraterrestrial radiation, S is the length of the day, S0 is the maximum
possible sunshine duration; a and b are empirical coefficients. We have added the radiation
variation with meteorological factors.
Data used are that registered each 10 minutes from January to November 2009. The
extraterrestrial solar radiation H0 is calculated from (3) [9]
     =      ∗          ∗   + .                        ∗                      +
Where n is the number of the day, φ is the latitude, δ is the solar declination and ω is the
sunrise hour angle.
With the multiple regressions, the established model is given in (4) :



                =− .       + .         + .         − .           +          − .
This model is similar to that obtained by Abdullah [10].
In Figure6 are represented daily measured solar radiations from 1th to 29th December and the
estimated radiation with the model (4).
The mean relative deviation MRD between measured values in December and calculated with
this model in (5):
      =                             = − . % (5)


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International Journal of Electrical Engineering and Technology (IJEET), ISSN 0976 – 6545(Print), ISSN
0976 – 6553(Online) Volume 3, Issue 3, October – December (2012), © IAEME




        The deviation is more important in cloudy days and smaller in sunshine days.


6. CONCLUSION

Solar house with all components power supplied in DC (12 V or 24 V) can be a real and
economic solution for isolated construction in Bejaia province or everywhere.
  he
The installation of a photovoltaic system is more accessible and more reliable with a DC
power supply.
Solar panel efficiency is considerably influenced by meteorological parameters. Solar
                                                                temperature
radiation intercepted by the panel increases with ambient temperature and atmospheric
pressure and decrease with relative humidity and wind speed.
From the measures recorded during twelve months and with a multiple linear regression a
global radiation model is established. Comparison between measured and calculated values
                                                     28.1%.
with the model shows a mean relative deviation of 28.1%. It will be performed and used to
forecast photovoltaic energy in relation with meteorological parameters.
                                                                                    wind
In Bejaia the wind speed in the evening can be exploited to produce an efficient wind-
photovoltaic hybrid system. Effects of marine pollution, Saharan dust and vehicle exhausts
will be a future study.

REFERENCES
    1. Skeiker, K. ‘Correlation of global solar radiation with common geographical and
                                                            Syria’,
       meteorological parameters for Damascus province, Syria’, Energy Conversion and
                                     331
       Management, Vol. 47 (4), pp. 331-345, 2006.
    2. Maghrabi, A.H., ‘Parametrisation of a simple model to estimate monthly global solar
       radiation based on meteorological variables, and evaluation of existingsolar radiation
                      bouk,
       models for Tabouk, Saudi Arabia’, Energy Conversion and Management (2009)doi
       10.1016/jenconman.2009.06.024
                                                     Graw Hill,
    3. Buresh,” photovoltaic energy systems”, Mac Graw-Hill, New York 1983.
    4. http://eosweb.larc.nasa.gov/sse available on september 9th 2009



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International Journal of Electrical Engineering and Technology (IJEET), ISSN 0976 – 6545(Print), ISSN
0976 – 6553(Online) Volume 3, Issue 3, October – December (2012), © IAEME


    5. Gwandu B.A.L. and Creasy D.J. « Humidity : afactor in the appropriate positionning
        of a photovoltaic power station”, Renewable Energy, Vol. 6 Issue 3, 1995, PP313-
        316.
    6. R. Alkama, F. Ait idir & Z. Slimani « Estimation and measurement of the automobile
        pollution : application to Bejaia case », Global NEST Journal Volume 8 N°3 Nov.
        2006, pp 277-281.
    7. A.N Celik, ‘Optimisation and techno-economic analysis of autonomous photovoltaic-
        wind hybrid energy system’ Energy Conversion and Management, Vol. 43, pp. 2453-
        2468, 2002.
    8. Angstrom A. Solar and terrestrial radiation. Quart J Roy Met Soc , Vol. 50, pp 121-
        125, 1924
    9. Tadros MTY. “uses of sunshine duration to estimate the global solar radiation over
        eight meteorological stations in Egypt” Renew Energy, vol.21,2000, pp.231-246
    10. Abdalla YAG.’New correlation of global solar radiation with meteorological
        parameters for Bahrain”. Int J Sol Energy VOl. 16, 1994, pp. 111-120.




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