2016 International Seminar on Intelligent Technology and Its Application
Calculation Of Electrical Energy With Solar
Power Plant Design
Retno Aita Diantari
Isworo Pujotomo
Lecturer, School For Engineering of PLN¶V Foundation
Jakarta, Indonesia
retno_aita@yahoo.co.id
Lecturer, School For Engineering of PLN¶V Foundation
Jakarta, Indonesia
isworop@yahoo.com
Abstract- In the future, the greater of the consumption
energy, the use of diverse energy sources can not be avoided.
Therefore, assessment of the various sources of energy
technologies continue to be developed. Photovoltaic
technologies that convert solar energy directly into electrical
energy using semiconductor devices is called solar cells. Solar
energy apart easily obtained from natural, environmentally
friendly too which does not produce CO2 emissions to become a
mainstay in the world of technology. The problem is how to use
solar panels to get optimal production of electrical energy as
solar panels are generally placed at a certain position without
change.
The design of this solar cells, built at roof over an area
of 50 m2 has a power output of 6 kWp with the installation of
solar panels with a slope of 6 degrees which can produce
electrical energy about 10,006.7 kWh per year. It is connected
to the grid (grid connected) without battery. For the
manufacture of solar investment of Rp. 445.453.328, - where
the investment already include the cost of maintenance and life
cycle costs over 25 years.
reduced by half if q = 600. Therefore, the need for setting
the direction of the solar cell panel that is always
perpendicular to the direction of the sun. Setting the
direction of the solar cell panel is less effective if done
manually by humans.
Keywords : renewable energy, solar power plant design,
electrical energy
I. INTRODUCTION
Indonesia has very good conditions for the
development of photovoltaic solar power systems due
mainly to the high mean daily radiation and the high number
of sunny days in most parts of the country. For this reason,
the government and companies working in the sector are
developing policies and investing in photovoltaic solar
power systems. One of the best features of rooftop solar PV
systems is that they can be permitted and installed faster
than other types of renewable power plants. They are clean,
quiet, and visually unobtrusive.
The problem is how to use solar panels to obtain
optimal power output. The solar panels are generally placed
at a certain position with no change (Pruit, 2001), for
example, solar panels faced upwards. By positioning the
panel facing upward and if the panel considered that the
object has a flat surface, the panel will receive maximum
solar radiation when the sun is perpendicular to the second
panel area. By the time the sun is not perpendicular to the
plane makes an angle q panel or the panel will receive less
radiation by a factor of cos q. By decreasing the radiation
received by the panel will obviously reduce the electrical
energy released by the panel. In fact, this energy can be
II. PHOTOVOLTAIC
2.1. Components of Solar PV System
Solar PV system includes different components
depended on your system type, site location and
applications. The major components for solar PV system are
solar charge controller, inverter, battery bank, auxiliary
energy sources and loads (appliances).
2.1.1. Solar PV Module.
It is an assembly of photovoltaic (PV) cells, also
known as solar cells. To achieve a required voltage and
current, a group of PV modules (also called PV panels) are
wired into large array that called PV array. A PV module is
the essential component of any PV system that converts
sunlight directly into direct current (DC) electricity. PV
modules can be wired together in series and/or parallel to
deliver voltage and current in a particular system requires.
2.1.2. Solar Charge Controller.
It is charge controller that is used in the solar
application and also called solar battery charger. Its function
is to regulate the voltage and current from the solar arrays to
the battery in order to prevent overcharging and also over
discharging. There are many technologies have been
included into the design of solar charge controller. For
example, MPPT charge controller included maximum power
point tracking algorithm to optimize the production of PV
cell or module. Solar charge controller ± regulates the
voltage and current coming from the PV panels going to
battery and prevents battery overcharging and prolongs the
battery life.
2.1.3. Inverter.
Inverter converts DC output of PV panels or wind
turbine into a clean AC current for AC appliances or fed
back into grid line. Inverter is a critical component used in
any PV system where Alternative Current (AC) power
output is needed. It converts Direct Current (DC) power
output from the solar arrays or wind turbine into clean AC
978-1-5090-1709-6/16/$31.00 ©2016 IEEE
443
electricity for AC appliances. Inverter can be used in many
applications. In PV or solar applications, inverter may also
be called solar inverter. To improve the quality of inverter's
power output, many topologies are incorporated in its design
such as Pulse-width modulation is used in PWM inverter.
Under these conditions, in this study the solar system
to be built is a solar system that is connected to the unit, the
merger is done on the consumer side (after kWh meters).
Systems connected to the electricity network, consisting of
component arrays of solar panels and inverters.
2.1.4. Battery.
In stand-alone photovoltaic system, the electrical energy
produced by the PV array cannot always be used when it is
produced because the demand for energy does not always
coincide with its production. Electrical storage batteries are
commonly used in PV system.
3.4. Calculating Total Solar Panels.
Specifications Solar Panels used are:
2.1.5. Inverter.
inverter is power electronic circuits that convert a
DC voltage to a AC voltage.
2.1.6. Load.
Load is electrical appliances that connected to solar
PV system such as lights, radio, TV, computer, refrigerator,
etc.
III. RESEARCH METHOD
3.1. Design of Solar PV Power Plant.
Based on the geographic location of STT-PLN 6o11
LS 104049 BT, the angle of incidence of solar radiation the
sun with low (21 December) is 60,30.
7$%/(,63(&,),&$7,2162)62/$53$1(/6
Model
Power
Peak Voltage
Peak Current
Open Circuit Voltage
Short Circuit Current
Compaint Size
Weight
Solar Cell Efficiency
Solar Cells
SFM 130
130 W
34.56 V
3.77 A
42 V
3.92 A
1076 X 806 X 35 mm
8 kg
17%
125*83.3
Number of Cells
72 pcs
The solar panels used are the type of monocrystal
solar panel. The solar panel has a maximum output power
(Pm) of 130 Wp per panel. So based on these specifications,
the number of solar panels required for solar to be built can
be calculated by using the following formula:
Number of Solar Panels =
3.2. Calculation of Power Generated.
Roof of the building of STT-PLN has assumed 50 m2
will be used for a solar panels to supply power, then to
calculate the solar generated power (Watt Peak) can be
calculated using the following formula:
(1)
PWatt Peak $UHDDUUD\[36,[ȘPV
With the array area is 50 m2, Peak Sun Insolation
(PSI) is 1000 W/m2 and solar panel efficiency is 17% for
using solar panels type monocrystal having an efficiency of
15% - 17% at a temperature of 25 0C then:
PWatt Peak = 50 m2 x 1000 W/m2 x 0.17
= 8.750 Wp
3.3. Determining Solar PV Power Plant System.
Solar PV Power Plant which will be built on the roof
of the building STT-PLN planned to supply electrical
energy STT-PLN building within a span of 07.00 a.m until
04.00 p.m.
=
ܲ ‫݇ܽ݁݌ ݐݐܽݓ‬
ܲ݉
ͺǤ͹ͷͲ ܹ
(2)
ͳ͵Ͳ ܹ
= 67.30
§Solar Panels
However, because of the preparation of the array
with the number of solar panels by 68 panels that hard to do,
then the number of solar panels to construct the array will be
converted into 64 panels. So that the peak output solar
power plant be built with the number of solar panels 64
panels is equal to:
Pwatt peak = Pmax x Number of solar panels (3)
Pwatt peak = 130 W x 64 = 8.320 Watt peak
And the value of Pwatt peak are 8.320 Watts, require
extensive array area:
Area Solar PV Power Plant =
ܲ ܹܽ‫݇ܽ݁݌ ݐݐ‬
ܲܵ‫ݔܫ‬ʉܸܲ
ͺǤ͵ʹͲ ‫ݐݐܽݓ‬
(4)
= ͳͲͲͲ ܹ Τ݉ ʹ ‫Ͳݔ‬Ǥͳ͹
= 48.94 m2
Fig 1. Wiring diagram Solar PV Power Plant System
444
From the panel of 64 panels that make up the circuit
panel 4 series (string) which is connected in parallel with
the first series consists of 16 panels are connected in series.
Solar panels are used as a reference is the solar panel
to the specifications Vm = 34.56 V, Im = 3.77 A and Pm =
130 W per panel (specifications can be seen in Table 1).
With these specifications, the large V m, Im, and Pm in the
array can be calculated as follows: V m array is 34.56 x 16 =
552.96 V, Im array is 3.77 A x 4 = 15.08 A and P m array is
522.96 V x 15.08 = 8338.63 Watt.
3.5. Calculation of Capacity Inverter.
In the selection of inverters, pursued his capacity
approaching capacity serviced power / load. This is so the
efficiency of the inverter becomes maximum. Solar array
which will be built on the roof of the building STT-PLN has
Pm at 8.320 Watt solar panels. In this system uses a
centralized three-phase inverter configuration (central
inverter).
7$%/(,,7(&+1,&$/'$7$,19(57(560&7/
Technical Data SMC 8000TL
Input Values
Output Values
Pdc max
8250 W
Vac nom
230 V
Vdc max
700 V
fac nom
50/60 Hz
Vdc Mpp
333-500 V
Pac nom
8000 W
Idc max
25 A
Iac max
35 A
Source : SMA,2011
By considering the losses in the system where the
loss occurred solar panels, inverters and solar panel
installations that include losses due to radiation levels of
2.5%, the losses due to the panel temperature of 16.3%, the
losses due to the quality of the panel 1.6%, unfortunate-loss
due to mismatch of 2%, the losses due to wiring 1.2%, the
losses at 3.5%, the inverter output power that can be
generated system are:
Losses = Output Power panel x 27.1%
= 8320 Watt x 27.1% = 2254.72 Watt
So the output power of the system is:
POut = Total Power panels installed - (Losses) = 8320 Watt ±
2254.72 Watt = 6065.28 Watt peak
3.6. Solar Panel Installation
3.6.1. Support Rack.
Solar Panel which will be built on the roof of the
building STT-PLN planned consists of 4 arrays. Where the
installation of one array consists of 16 panels which will be
divided into two parts rack buffer, with one rack buffer will
consist of 8 panels as shown below. Buffer rack is made of
steel UNP size of 80.40, size angle iron of 50.50.5, and iron
plate size of 150 x 150 with a thickness of 10 mm.
3.6.2. Preparation of Panel.
Preparation of solar panels on the rack support is
very important to avoid shading by constructing solar panels
horizontally (landscape). A large number of rows in the
preparation of 2-5 rows of solar panels due consideration of
the factors of wind and shadow. So the length and width of a
buffer shelf with 2 rows of solar panels are as follows:
= (N x Ppanel) + (N-1) x C (5)
Parray
= (R x Lpanel) + (R-1) x C (6)
Larray
If the above formula is converted to the data obtained
in the above then:
= (8 x 1.076m) + (8-1) x 0.02 m
Parray
= 8.748 m
= (2 x 0.806m) + (2 ± 1) x 0.02m
Larray
= 1.632 m
3.6.3 Installation of Distance Between Array Solar Panel.
To avoid shadow effects that can be caused by the
panel, then the installation of the array should be spaced.
The distance between the array can be calculated by :
•‹ ߚ
൅ ‘• ߚቃ
d=Wx
–ƒ ߙ
(7)
•‹ ͸
൅ ‘• ͸ቃ = 1.72 m
= 1.632x
–ƒ ͸ͲǤ͵
Solar panels installed on the roof of the building STTPLN facing north because of the geographical location of
the building STT-PLN is in the southern hemisphere with a
slope of panels 60 (Foster et al, 2010) that the power output
can be maximized throughout the year. The number of
arrays that will be built on the roof of the building STT-PLN
by 4 array with the number of panels per array 16 and the
minimum distance of 1.72 m each array.
IV. RESULTS AND DISCUSSION
4.1. Analysis of Cost Solar PV Power Plant.
The cost of solar energy is different from the
energy costs for conventional plants. This is because the
cost of solar energy is influenced by the high initial
investment costs with the costs of maintenance and low
operating.
4.2. Cost of Investment.
Initial investment costs for solar to be built on the
roof of the building STT-PLN includes costs such as costs
for solar components, the cost of solar panels and shelves
buffer solar installation costs. The totally cost for this Solar
PV Power Plant components consist of fees for the purchase
of solar panels and inverters : Rp.410.845.000,4.3. Cost of Maintenance and Operations.
Maintenance and operational costs per year for
generally accounted for 1-2% of the total cost of investment
(Lazou and Papatsoris, 2000; Abdel-Ghani, 2008). As for
the cost of maintenance and operations (M) per year for
solar to be constructed as follows:
M
= 1% x investment cost
(8)
= 0.01 x Rp. 410.845.000,= Rp.` 4.108.450,- / year
4.4. Calculation of Life Cycle Costs
Life Cycle Cost which will be built on top of the
building STT-PLN, determined by the present value of the
current of the total cost of solar systems consisting of initial
investment costs (C) and long-term costs for maintenance
445
and operasional (MPW). So that the life cycle costs in this
study can be calculated with the following formula:
LCC = C + MPW
(9)
Solar PV Power Plant on this research, it is assumed
to operate for 25 years. The amount of the discount rate (i)
that is used to calculate the present value in this study was
11%. The determination of the discount rate refers to the
interest rate bank loans as of June 2011, ie an average of
10.77% (Vibiznews, 2011). Large current value (present
value) for the maintenance and operational costs (MPW)
PLTS during the project life of 25 years with a discount rate
of 11% is calculated by the following formula:
ሺͳ൅݅ሻ݊ െͳ
P
= Mቂ
(10)
݅ሺͳ൅݅ሻ݊
MPW (A11%, 20)
= Rp. 4.108.450,- ቂ
= Rp. 4.108.450,- ቂ
ሺͳ൅ͲǤͳͳሻʹͷ െͳ
ͲǤͳͳሺͳ൅ͲǤͳͳሻʹͷ
ͳʹǡͷͺͷ
ͳǡͶͻͶ
= Rp. 34.608.328,Based on the initial investment cost (C) and the
calculation of the MPW life cycle costs for solar to be built
during the project life of 25 years is:
= C + MPW
LCC
= Rp. 410.845.000,- + Rp 34.608.328,= Rp. 445.453.328,4.5. Calculating kWh Solar Production.
Based on the radiation data for the Jakarta area, the
annual energy that can be produced Solar PV Power Plant
are:
Energy = maximum output power system x
daily radiation x 365
= 6.078,86 Wp x 4.51 kWh/m2/day x 365
§N:K\HDU
Proceeds from sale of electricity =
10006,76 kWh/year x 25 year x Rp. 3.000,-/kWh = Rp.
750.507.000,-**
**assumed price of solar electricity $ 0.25 / kWh with
exchange rate of $ 1 = Rp 12,000, V. CONCLUSION
1. The optimal design of solar power plant can be done on
the roof at STT-3/1¶VEXLOGLQJ
2.The solar cells used in photovoltaic plants convert
sunlight directly into electrical energy. Planning large
facilities is a very complex process, however. This causes
a problem, however, because increasing the distance
between modules means fewer installed modules and thus
less overall output. Planning engineers therefore have to
make technical and economic compromises for a large
number of parameters, while still meeting customer
446
requirements regarding aspects such as minimum output
or cost limits.
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PV Power Station Access´(/6(9,(5 [4]. Imran Hamid, M dan Anwari Makbul, 2010, Single Phase
Photovoltaic Inverter Operation Characteristic in Disributed
Generation System.
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[6]. Mevin Chandel, G. D. Agrawal, Sanjay Mathur, Anuj Mathur,
³7HFKQR-Economic Analysis of Solar Photovoltaic power plant for
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6\VWHP)RU393RZHU3ODQWV´$FWD3RO\WHFKQLFD+XQJDULFD [11].Yuan, Xiaoming and Zhang, Yinggi, 2012, Status and Opportunities
of Photovoltaic Inverters in Grid-Tied and Micro-Grid Systems.