AN ECONOMICAL AND RELATIVELY
EFFICIENT IMPLEMENTATION OF THE
REAL–TIME SOLAR TRACKING SYSTEM
Sabir Ali Kalhoro
Department of Electronics Engineering NED University of
Engineering and Technology, Karachi (Pakistan)
E–mail: sabir13es66@gmail.com
Sayed Hyder Abbas Musvi
Indus University. Karachi (Pakistan)
E–mail: dean@indus.edu.pk
Sikandar Ali
Indus University. Karachi (Pakistan)
E–mail: sikandar.shah@indus.edu.pk
Saadullah Rahoojo
Department of Geography, University of Sindh. Jamshoro (Pakistan)
E–mail: rahoojosaad@gmail.com
Asim Nawaz
Department of Geography University of Karachi. Karachi (Pakistan)
E–mail: asimpmd@gmail.com
Recepción: 05/03/2019 Aceptación: 27/03/2019 Publicación: 17/05/2019
Citación sugerida:
Kalhoro, S. A., Abbas Musvi, S. H., Ali, S., Rahoojo, S. y Nawaz, A. (2019). An
economical and relatively ecient implementation of the Real–Time Solar Tracking
System. 3C Tecnología. Glosas de innovación aplicadas a la pyme. Edición Especial, Mayo 2019, pp.
68–99. doi: http://dx.doi.org/10.17993/3ctecno.2019.specialissue2.68–99
Suggested citation:
Kalhoro, S. A., Abbas Musvi, S. H., Ali, S., Rahoojo, S. & Nawaz, A. (2019). An
economical and relatively ecient implementation of the Real–Time Solar Tracking
System. 3C Tecnología. Glosas de innovación aplicadas a la pyme. Special Issue, May 2019, pp.
68–99. doi: http://dx.doi.org/10.17993/3ctecno.2019.specialissue2.68–99
3C Tecnología. Glosas de innovación aplicadas a la pyme. ISSN: 2254–4143
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ABSTRACT
The bi–facial solar system which is available in the commercial markets having a
variety of advantages and eciency but they are too much costly. Therefore there
is a dire need to design a low price solar system that overcomes the increasing
energy demand. In this research, we have designed a system which reects the
bi–facial model with an economical prize for the developing nations. However,
the eciency of the proposed solar system was checked on a sunny day and
its observation was closely related to the real–time bi–facial solar system. The
prototype has been designed by combining the two equal watts solar penal having
anti–parallel alignment with each other. The rear penal of the design system
is supported by concentrator for strengthening the eciency of the scattered
irradiation. The scattered irradiation generates extra energy due to the design
structure of the proposed system. The voltage of the system is conjoint increases
slightly as the timely increasing irradiation strength. The power of the designed
system increases with the increasing voltage proportional relationship with the
current. The design system veries the voltage, current and power measurement
from all location of the calculation.
KEYWORDS
Renewable Energy, Solar System, Ecient Design System.
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1. INTRODUCTION
Nowadays deciency of energy issues has been increasing which causes social
and environmental problems, however, the developing countries urging the
researchers to seek out alternative resources which may balance the demand for
fossil fuel.
The alternative source like solar and wind are highly available to fulll the
increasing demand (Guerrero–Lemus, Vega, Kim, Kimm & Shephard, 2016).
While freely available solar irradiation is a reliable source of solar power
generation and solar energy will be generated easily by harnessing the facility of
the radiation, this energy source is clean and environmental friendly (Jia, Gawlik,
Plentz & Andrä, 2017; Luque, Torres & Escobar, 2018). The energy from the sun
intercepted by the earth is roughly 1.8x1011MW which is several thousand times
larger than the current consumption.
The most drawbacks with solar power are its dilute nature. Even within the
hottest regions on the planet, the irradiation ux available nearly is inadequate for
technological utilization. This drawback may be corrected by many techniques
which ensure the greatest intensity of sun rays striking the surface of the panel
from sunrise to sunset (Kim, Kim & Hwang, 2018; Duan, Zhao, He & Tang,
2018). This drawback can be overcome by the advanced design system, which is
a bifacial solar system, it may generate electricity from either front or rear face, it
will consider as the advanced photovoltaic system. This system is the noticeably
exaggerated physical phenomenon of advance conversion system (Lamers, et al.,
2018). We tend to gift here such type of model which associates in the alternating
deposition technique such as bi–facial solar cells (Liu, Zhao, Duana, He, Zheng
& Tang, 2018). Such type of photovoltaic unit maximizes the output power by
utilizing both sides of the PV cell to capture the maximum irradiation. The bi–
facial solar device yields and maximizes the eciency of available system and this
strategy provides new opportunities for fabricating high performance (Lo, Lim &
Rahman, 2015; Sun, Khan, Deline & Alam, 2018). Bi–facial solar system which
harvests the incident light irradiation from the front face and collects scattering
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light irradiation with the help of concentrator to facilitate the rear surface for the
maximum utilization of light irradiation, therefore, system gain the best power
outputs.
The rear face uses to increase the eciency of the solar system as well as support
the name bi–facial. The traditional aluminum metal is used to collect the scattered
irradiation to get advantage from the useless irradiation and provide support to
the rear pedal. The rear penal adds its power to increase the eciency of the
overall solar system. The scattered irradiation plays a signicant rule for the rear
side of the solar penal. The rear penal gets the advantage from the scattered
irradiation to extract the maximum power from the bi–facial solar system (Pan,
Cardoso, & Reis, 2018). This system has a relatively little bit less photoelectrical
conversion potency of the rear penal as compare to the front penal. The proposed
system provides a signicantly attainable application in the existing solar system.
Generally, the designed system organized in well–observed alignments, thus
partial sunlight is mirrored by the concentrator and throw toward the rear penal,
so that requires energy might convert into thermal energy with the high eciency
by using the advanced bi–facial solar system (Zhu, Wang, Wang, Sun, He & Tang,
2017).
The concentration of scattered irradiation in rear surface increases the overall
eciency of the designed system. All solar panels are in a much–maligned
arrangement in a real application of electrical phenomenon power stations. The
high–eciency solar system expected to gain the scatter irradiation with the
help of concentrator (Rodriguez, et al., 2018). The metallic portion encompasses
a well–made reection to the incident irradiation resulting in comparatively
eective implementation of the system eciency. A major motivation for the
proposed system with a concentrator that is a program by the microcontroller
known as Raspberry Pi for tracking the system to yield the additional energy.
The mono facial panels are not so much reliable due to the light sensitivity as
compare to the bifacial solar system. Most of the panel is using single access
tracking system but we are motivated to design the bi–facial solar tracking system
having two sides for the power extraction sides X at the front and Y for the
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rear penal to collect the scattered irradiation (Wang & Lu, 2013; Patil & Asokan,
2016). The potential of this improved module power output and energy yield
was repeatedly commendable from all measurements through installations in
numerous orientations. However, uncertainties regarding the particular output
of this projected system still deter attainable investors. Even within the solar
community, the important quantitative prot thanks to the bifacial system to suited
technical ideas square measure still below discussion. The bi–facial solar system
will dramatically improve the condition of generation compared to the existing
solar system, so this type of advance model will gain a lot of attention in the future.
This advanced solar model has been investigated intensively and characterized
largely in the eld with completely high gain. The proposed systems will provide
the lump sum output power gain of the front and rear penal measurement. Such
measurements were very reliable, so typically the dierent installation angles and
backgrounds were terribly support to the eective measurement (Khalil, Asif,
Anwar, Haq & Illahi, 2017). Basically, the performance of this bidirectional
solar system originates from the strength and angle of each location, and the
scattered irradiation from the background at the rear penal. The precise nature
of the bidirectional solar system would be more characterize at the well–dened
research laboratory. Signicantly the irradiation intensity level and the angle
dependence area unit are highly important. The strength and angle dependences
are individually investigated; no systematical collaborative investigations are
performed on bidirectional solar system module.
In the old era mono–facial, solar cells were used without any tracking system.
These systems were useful but with respect to time technology continuously
changing by the research and technology by Scientist and demand by the
consumers. They used mono–facial solar cells in combination with single access
tracking system to increase the eciency of the solar tracking system (Khan, et
al., 2017). The rule of a bidirectional module is similar to it of a mono–facial
one. In a mono–facial module, light radiation enters through the front side that
absorbed by the solar PV and reborn into electrons that give electrical power. In
this bidirectional module, an equivalent front side light irradiation assortment
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method happens and, additionally, light radiation is absorbed from the backside
of the module (Rajshree, Jaiswal, Chaudhary & Jayswal, 2016). This rear penal
gets the solar irradiation source from the reected collection of the irradiations
by the concentrator from the ground or a neighboring row of PV modules. The
extra light radiation generates a lot of electrons within the cells that primarily
will increase the module eciency. The voltage of the cell conjointly will increase
slightly as the timely increasing irradiation strength so the power is increased
because of the increasing voltage proportional relationship with the current.
The most typical, bidirectional modules conguration is economical and
viable reliable for the local as well as commercial usage. Bi–facial PV systems
are highly compatible with already existing PV systems and generally achieve a
markedly higher energy yield than mono–facial systems (Brady, Wang, Steenho
& Brolo, 2019). At the same time, bifacial systems are competitive because the
manufacturing costs for the solar cells are slightly lower and the modern cell types
are inherently bifacial and do not involve additional costs. Certied production
technologies for the large–scale manufacture of bifacial cells and modules are
already available on the market. The bifacial systems can be planned in exactly
the same way as mono–facial systems, with a few factors demanding the extra
attention, for example, the properties of the reective ground. This attention will,
however, be rewarded with a higher energy yield. Bifacial modules are opening
up new application possibilities, often arising from the dual use of the installation
area. All in all, bifacial modules can be employed to good advantage for most
applications in terms of energy yield (Ooshaksaraei, Sopian, Zulkii, Alghoul &
Zaidi, 2013). The single access tracking system is to work only one direction with
the help of dierent microcontrollers. The proposed bifacial modules produce
solar power from both sides front and rear side. Whereas the traditional panels
are only designed to convert solar irradiance from one side of the module into dc
power, the bifacial modules are manufactured with clear plates on both the front
and back side of the solar cells. They are designed to convert solar irradiance
from both sides into dc power (Solarworld, in google). Similar to mono–facial
modules, bifacial modules come in a variety of types including framed and
frameless. The reason for this growth in engagement with bifacial technology is
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the capacity to extract maximum power by utilizing the scattered irradiation. It
has been calculated from the experiment that this model is able to increase the
power output compared to the available solar conguration (Sengupta, 2016).
The bi–facial with the tracking system has been made an eort to track the motion
of the sun for collecting maximum energy. The power generation with the help of
a bi–facial solar tracking system is much more as compared to the single axis solar
tracking system. In two several places, the require generation of the electricity is
through the pricy fossil fuels. The user subjected to implies the restriction and
pollutant environment that accompanies by fossil fuels (Renewables 2017 Global
Status Report, 2017). The value intensive system should be placed in the way to
protect the infrastructure and environment pollution. This implies the renewable
energy to fulll the growing demand. Today demand requires an easy plug and
play electricity setup which provides an abundant solution in the way of power
generation and consumption. This system involves in the autonomous frequent
maintenance which will allow the alternative energy generation in an exceeding
system which will be carried out in the form of the solar system (Livingston,
Sivaram, Freeman & Fiege, 2018).
2. MODEL AND METHODS
The bi–facial solar system model provides an eective measurement of power. The
solar radiation such as global, diuse and direct irradiation is fallen on the design
solar system. These models are representing the principal climate phenomena
to attain solar electricity. We analyze the output power of the proposed design
system which is highly depending upon the Global Horizontal Irradiation (GHI)
as well as Global Tilted Irradiation (GTI). The power of the system depends
upon solar irradiation received by the surface of photovoltaic modules and the
GHI is the sums of the direct and diuse solar radiation [kWh/m2]. The GHI is
considered as a climate reference as it is an important parameter to check for the
solar PV installation.
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The elevation angle measured relative to the sea level (ELE), also determines the
optimum choice of a site and performance for the solar energy system. Elevation
Angle can be measured by applying Eq. 1
Eq. 1
The zenith angle is the angle between the sun and the vertical. Thus making the
zenith angle = 90° – elevation as under Eq. 2.
Eq. 2
DNI (Direct Normal Irradiation): Solar radiation component that directly reaches
the surface kWh per m square. It is signicant for the proposed system as Eq. 3.
Eq. 3
DIF (Diuse Horizontal Irradiation): Solar radiation component that is scattered
by the atmosphere in kWh/m2 Eq. 4.
Eq. 4
GHI (Global Horizontal Irradiation): The GHI is the Sum of direct and diuse
solar radiation, kWh/m2. It is considered as a climate reference as it is an
important parameter to check for the solar PV installation which can be seen in
Eq. 5.
Eq. 5
Atmospheric temperature, known as the air temperature is another most
important variable determining the ecient performance of solar power systems.
The air temperature degrees or degrees determines the temperature of PV cells
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and modules and has a direct impact on PV energy conversion eciency and
resulting energy losses. Air temperature also some other weather parameters
are the main part of each solar project assessment as they regulate the eective
conditions and operation eciency of the solar power plant (Please refer Eq. 6).
Eq. 6
The solar module is the most widely applied and also the most versatile technology
for the power generation. The solar electricity simulation algorithm, incorporated
in the atlas always provides an approximate estimate of the potential photovoltaic
energy, which can be produced at any location covered by the interactive map, as
shown in Eq. 7.
Eq. 7
Air temperature determines the temperature of PV cells and modules and has
a direct impact on PV energy conversion eciency and resulting energy losses.
The operating conditions and operation eciency of the solar power plant can be
related to the air temperature model is given to nd out the eecting temperature
on the system as Eq. 8.
Eq. 8
The solar radiation model, air temperature model and PV power simulation
model. These models provide location–specic solar radiation and temperature
data. In order to calculate an on–demand utility by assessing the possible PV
system type and conguration, the PV power simulation models are employed.
The air temperature model and another PV power simulation model are given
to nd out the eecting temperature on the system as below Equations Eq. 9–11.
Eq. 9
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.
Eq. 10
Eq. 11
The long–term yearly solar resource estimates by satellite–based models can be
characterized by calculating the bias (systematic deviation) at the validation sites,
where high-quality solar measurement are available. Also the World Bank choose
the same as Eq.1-11 for solar potential calculation in the in the solar atlas so here
these Eq.1-11 reect the same model in this design system.
The polynomial function expresses the estimated best t of the designed solar
model at the available irradiation for the eciency dierence measurement of
front and rear penal of the proposed solar system on any day of the month line
by general polynomial function model, represented as Eq. 12.
Eq. 12
or
The voltage measurement of the proposed design solar system for the front and
rear penal is tted for the eciency dierence checking as shown in Figure 7. We
have selected the dates from 08 to 10 of the Feb 2019 by using the polynomial
regression of 6 degrees as, The quality of the best t for the design system with
the measured voltage data is determined by the value of R2 being close by 1. In
the case of voltage data the R² = 0.993 for the front penal and R² = 0.9754 for
the rear panel. With the application, the polynomial of six degrees seems to be
the best t on the available data. The best t in the case of front penal as shown
in the Eq. 13.
y = –0.0002x6 + 0.0102x5 – 0.1795x4 + 1.6129x3 – 7.9224x2 + 21.999x – 15.328
Eq. 13
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And in the case of rear penal shown in the Eq. 14.
y = 0.0003x6 – 0.0135x5 + 0.2317x4 – 1.9128x3 + 7.4858x2 – 9.0814x + 3.4818
Eq. 14
The measurement of current for front and rear solar penal is tted for the
eciency dierence checking of the designed solar system as shown in Figure 10.
We have selected the dates from 08 to 10 of the Feb 2019 with the polynomial
regression of 6 degrees as, The quality of the best t with the irradiation data
is determined by the value of R2 being close by 1. In this case R² = 0.9595 for
the front penal and R² = 0.9509 for the rear penal. With the application of the
polynomial to 6th degree seems to be the best t on the available data. The best
t in the case of front penal as shown in the Eq.15.
y = 6E–05x6 – 0.0029x5 + 0.0508x4 – 0.4443x3 + 1.9444x2 – 3.3536x + 1.8066
Eq. 15
And in the case of rear penal as shown in the Eq. 16.
y = 7E–05x6 – 0.003x5 + 0.0513x4 – 0.4341x3 + 1.849x2 – 3.1683x + 1.7129
Eq. 16
The power measurement of front and rear solar penal is tted for the eciency
dierence checking as shown in Figure 13. We have selected the dates from 08
to 10 of the Feb 2019 with the polynomial regression of 6th degree as, The
quality of the best t for the designed bi–facial solar system with the irradiation
is determined by the value of R2 being close by 1. In this case R² = 0.9677
for the front penal and R² = 0.9676 for the rear penal. With the application
of the polynomial 6th degree seems to be the best t on the available power
measurement data. The best t in the case of front penal as shown in the Eq. 17.
y = 0.0007x6 – 0.0323x5 + 0.5627x4 – 5.0022x3 + 23.254x2 – 43.174x + 24.743
Eq. 17
And for the case of rear penal as shown in the Eq. 18.
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y = 0.0007x6 – 0.0276x5 + 0.4603x4 – 3.9598x3 + 18.306x2 – 34.732x + 20.41
Eq. 18
3. SYSTEM DESIGN AND IMPLEMENTATION
The proposed design solar system have Light dependent resistors (LDR) that use
the light sensing element. We are using two 12 volts to a gear dc motor. The dc volt
geared the motor so it is used for east–west tracking and other geared dc motor
with a threaded rod for the linear up–down motion for north–south movement.
The LDR’s are sensing the light intensity as shown in Figure 2. The tracking of
sun movement, in that way we can get optimum power of the solar system. The
main object of the design system is to gain maximum power from the sun. The
design system supports the tracking strategy as the annual motion of sun at 23.5o
degree in east–west direction is occurred. In this project, the relay module is used
for converting binary data to electrical output. The design system is controlled by
the microcontroller known as raspberry pi. The raspberry pi is the main control
unit of the design system. The raspberry pi microcontroller gets a signal from the
sensor that decides the direction of the movement of the motors in the required
axis. The python is used to program the raspberry pi for the tracking and control
purpose. The Python is associated with the interpreter, interactive programming
language. It incorporates modules, exceptions, dynamic writing, and terribly high
level of dynamic knowledge.
3.1. BLOCK DIAGRAM
The basic blocks diagram consisting of Solar PV Panel, light dependent resistor
(LDR), raspberry pi, relay module, analog to digital converter (ADC), power
supply, and battery. The panel gets the irradiation and converts it into electricity
or electrical signal. This generated electricity hold in the battery for upcoming
use. The power will be ow from solar panels to store in the battery. The battery
will be charged fully and get alarms for disconnection within the event of a fault.
The microcontroller is placed in between the solar penal and battery for the
tracking and the system control. The microcontroller has been used to generate
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the control commands from the LDR sensor. The microcontroller oers the
motion to the motor to rotate the parabolic dish. The design system accuracy
depends upon sensor and its accuracy is important for the successful performance
of the algorithm. The last block is load, we are able to use any kind of dc load
here as we have not inserted electrical converter block within the design system.
The ac appliances on solar panels we need to feature electrical converter block
in on top of the diagram in order that it can convert dc power provided by the
solar battery into ac.
Figure 1. Flow Diagram of the Design Solar System.
3.2. EXPERIMENTATION
The potency of a mono–facial solar module is expected to decrease considerably
as compared to the availability of the irradiation thanks to the bi–facial solar