PART I
INTRODUCTION
1.1. Background Of The Problem
This paper is deliberately written in a colloquial style that is very easy to
understand and be understood. This paper is based on the chapters, so that the reader can be
facilitated to find subject matter that has been read.
In the preparation of this paper does not intend nothing but encourage the reader to
understand the "SOLAR CELL" and the preparation of this paper fatherly fulfill the task TE
academic year 2010/2011. Hopefully we can understand about the utilization of solar energy
which Solar Cell.
1.2. Purpose
The purpose of this paper is to know about PLTS some things.
There are:
a. Meet the TE task academic year 2010/2011
b. Knowing the advantages and disadvantages of solar cell
c. Knowing how it works
1.3. Formulation Of The Problem
In the utilization of solar energy as solar power, especially Solar cell, there are some
problems. However, the authors only discuss the issue based on the following constraints:
1. Introduction Solar Cell
2. Benefits of Solar Cell
3. Excess solar cell
4. Lack of solar cell
1.4. Writing methods
The method we use in the preparation of this paper is to study methods of literature that is
taking resources related to the title of the book and the Internet.
CHAPTER II
DISCUSSION
2.1. Introduction of Solar Cell
A solar cell (photovoltaic cells) is a semiconductor equipment to convert the photon energy
into electrical energy.
The need for energy is increasing and the depletion of petroleum reserves forcing people to
look for alternative energy sources. Developed countries have also been competing and
competing to make new breakthroughs to seek and explore and create new technologies that
can replace petroleum as an energy source.
The depletion of energy supply as well as dependence on one type of energy that until now
the use of fuel oil is immense and almost every sector of life using this fuel, while fuel oil is
the dominant export commodity for state revenues.
In the search for new energy sources should qualify that produce sizeable amounts of energy,
economical cost and no negative impact on the environment. Therefore, the search is directed
at the utilization of solar energy either directly or indirectly by using solar cell panels that can
transform solar energy into electrical energy called a solar cell.
Solar cell is a panel consisting of several cells and various types. The use of solar cell has
been widely used in developing countries and developed countries where its use is not only
the small scope but is already widely used for industrial purposes so that solar energy can be
used as an alternative energy source.
Solar energy has many advantages compared with other energies. Advantages that can be
obtained is large enough, a continuous, non-polluting, found everywhere and not spend.
a. Classification of Solar Energy.
NASA's Solar Energy Panel of the National Aeronautic and Space Administration) in 1997 to
classify the use of solar energy into two systems, namely collection natural collection systems
and collection systems technology. From the above classification for natural collection:
water, wind, organic fuel and temperature differences in the ocean while for the collection of
technology, there are two main applications of solar energy is electricity production
(photovoltaic) and thermal heat production.
Photovoltaics are used to convert the intensity of solar radiation into electrical energy. Heat
energy generated from solar radiation and also can be collected or concentrated by collectors
(collector). This heat energy is usually used for solar collectors, heating pumps and others.
b. Solar radiation.
Solar radiation intensity will be reduced by absorption and reflection by the atmosphere
before reaching the earth's surface while. Ozone in the atmosphere absorbs short wavelength
radiation (ultraviolet) while carbon dioxide and water vapor absorbs most radiation with a
longer wavelength (infrared). In addition to the reduction of direct radiation from the earth
(beam) by absorption, there is still radiation emitted by molecules of gas, dust and water
vapor in the atmosphere.
2.2. Benefits of Solar Cell
Advantage of the economic side of the solar cell utilization, among others:
1. Save, because it does not have to require fuel;
2. Can be installed anywhere and can be moved as required;
2. Can be installed anywhere and can be moved as required;
3. Can be applied centralization (PLTS is set in an area and the electricity produced is
channeled through the distribution network to the place where it is needed) and decentralized
(each system stand alone / individual, does not require the distribution network);
4. Characteristically modular. The capacity of the electricity produced can be adjusted by
means of arranging the modules in series and parallel;
5. Can be operated automatically or using operations;
6. Without sound and does not pose environmental operations.
2.3. Principle Working of Solar Cell
Solar electricity using sunlight as a source of electricity. Solar energy is given by
God to us. The main tool to capture, change and generating electricity is called photovoltaic
or generally Module / Panel Solar Cell.
With these tools sunlight converted into electricity through a process of stream-flow positive
and negative electrons in the cell module due to the difference electron. Results from the flow
of electrons will be the DC power that can directly dimanfatkan to charge battery / battery
according to the voltage and amperage required.
Installation, to install solar power, actually not too difficult, can be done alone
anyway, the main component Solar panels installed facing the sun with high intensity, then
connect the Battery for energy storage media (DC current), to use we can connect the AC
current to DC to AC Converter and ready to be used for domestic purposes (lights, TV,
refrigerator, etc.). Remember amount of charged, not to overload.
Solar cells can be used without pollution, both air and noise pollution, and in all weather.
Solar cells have also been used to provide power for all satellites orbiting the Earth nearly 30
years. Solar cells have no moving parts, yet easily moved as needed.
All the above advantages of solar cells due to the typical characteristics of solar
cells that convert sunlight directly into electricity.
Conversion process
The process of conversion or the conversion of sunlight into electricity is possible
because of the materials that make up the solar cells in the form of a semiconductor. More
precisely composed of two types of semiconductors; namely the type n and type p.
N-type semiconductor is a semiconductor that has an excess of electrons, so that the excess of
negative charge, (n = negative). While the p-type semiconductor has excess holes, so called p
(p = positive) because of excess positive charge. How, by adding another element into
semkonduktor, then we can control the type of semiconductor.
At first, the manufacture of two types of semiconductors are intended to improve the level of
conductivity or ability level electrical and thermal conductivity of semiconductor experience.
In natural semiconductors (so-called intrinsic semiconductor), the electron and hole have the
same number. Excess electrons or holes can improve the electrical and thermal conductivity
of a semikoduktor.
Suppose that mean that the intrinsic semiconductor silicon (Si). P-type semiconductor,
usually made by adding boron (B), aluminum (Al), gallium (Ga), or indium (In) to the Si.
Additional elements will increase the number of holes. While the n-type semiconductor
prepared by adding nitrogen (N), phosphorus (P) or arsenic (As) into the Si. From here, the
extra electrons can be obtained. Meanwhile, the intrinsic Si itself does not contain additional
elements. This effort adds an additional element called the doping amount is not more than
1% compared to the weight of Si to be in-doping. Two types of semiconductor n and p is
taken together will form a pn junction or pn diode (another term call connection metallurgical
/ metallurgical junction).
Shortly after these two types of semiconductors are connected, there is transfer of electrons
from the semiconductor p n towards semiconductor, and holes of semiconductor
displacement toward semiconductor p n. The displacement of electrons and holes is only up
to a certain distance from the boundary initial connection.
Electrons from the semiconductor n united with the hole in the semiconductor p which
resulted in the number of holes in semiconductor p will be reduced. This region eventually
become more positively charged. At the same time. hole of semiconductor p united with
electrons present in the semiconductor n that causes the number of electrons in this region is
reduced. This area is ultimately more positively charged.
Negative and positive area is called the depletion region (depletion region) is marked with the
letter W. Both electrons and holes that exist in the depletion region called minority carriers
(minority charge carriers) because of its presence in different types of semiconductors.
Due to differences in positive and negative charges in the depletion region, it arises by itself
the internal electric field E of the positive side to the negative side, which is trying to pull
back hole to the semiconductor p and n electrons into the semiconductor. The electric field is
inclined opposite to the hole or electron transfer at the beginning of the depletion region
(number 1 above).
The existence of an electric field resulting pn junction is at a point of equilibrium, the
moment in which the number of holes to move from the semiconductor p n compensated by
the number of holes which attracted back towards the semiconductor p due to the electric
field E. Similarly, the number of electrons that move from smikonduktor n to p, compensated
by the flow of electrons into the semiconductor back n due to the pull of the electric field E.
In other words, the electric field E prevents all electrons and holes move from one
semiconductor to another semiconduktor.
In the process of converting this pn junction solar light into electricity occurs. For the
purposes of the solar cell, semiconductor n are in the top layer of p connection is facing
towards the coming of the sun, and made much thinner than the semiconductor p, so that the
sunlight that falls onto the surface of the solar cell can continue to be absorbed and enter the
depletion region and the semiconductor p.
When the connection is exposed to sunlight semiconductor, the electrons gain energy from
sunlight to rid itself of the semiconductor n, and the semiconductor depletion region. This
release electrons leave holes in the area vacated by the electron is called the electron-hole
fotogenerasi (electron-hole Photogeneration) namely, the formation of pairs of electrons and
holes from the sun.
Solar light with a wavelength (denoted by the symbol "lambda" sbgn in the picture above) are
different, making fotogenerasi the pn junction is located at the pn junction different. Red
spectrum of sunlight that have wavelengths longer, able to penetrate the depletion region to
be absorbed in a semiconductor p is ultimately generate fotogenerasi process there. Blue
spectrum with wavelengths much shorter only absorbed in the semiconductor region n.
Furthermore, due to the pn junction there is an electric field E, the electrons results
fotogenerasi gravitate toward the semiconductor n, as well as the hole is drawn toward the
semiconductor p. If the cable is connected to two series of semiconductor parts, the electrons
will flow through the cable. If a cable is connected to a small lamp, the lamp lights up
because the received electric current, whereby an electric current arises due to the movement
of electrons.
In general, to introduce the workings of solar cells in general, the illustration below explains
everything about the process of converting sunlight into electrical energy.\
2.4. The advantages of Solar cell (using solar panels)
Solar energy, natural energy that will not run out and we can use it wherever we are.
The moment a sunny day, the sun is shining on the earth's energy to produce an average of 1
kW / m ² area of the earth, meaning within 1 hour of energy required worldwide to 1 year.
If the solar energy can be absorbed over 1% of the surface area of the earth, it will
cover the consumption of electrical energy needed for the entire world. Earth's surface
illuminated by the sun with a number of very large volumes. Solar panel technology has been
developed extensively and potential. Having developed a thickness dimension of solar panels
become thinner and without losing its function to obtain an efficient solar energy. In addition,
do not cause pollution or greenhouse gas emissions so as to reduce global warming.
Can be built in remote areas because it does not require energy transmission and
transportation of energy resources. Indonesia is a country that has a lot of the remoteness of
the area. This happens because Indonesia is too large, then the Solar cell development is very
beneficial for the village.
2.5. The disadvantages of Solar Cell
Some disadvantages of solar cell are:
1. Solar cell development is still a great need of investment. Some components ranging from
solar panels, batteries, until the LED light remains to be imported from lluar country;
2. Just for comparison, the cost structure of solar power until now dominated by the price of
solar panels are still expensive. The greater the size and capacity of the solar panels also the
more expensive the price of solar power systems;
3. Inefficient if developed in a polluted area. Pollution is also a factor that inhibits the
development of this technology, because it can reduce the intensity of light that can be
accepted by the panel / solar cell. So in other words the energy produced is relatively small.
CHAPTER III
MAKING SOLAR CELL
3.1. Tools and materials
Tools and materials required to make solar cells, among others:
1. A shiny copper sheet;
2. Two alligator claws;
3. A Micro ammeter that can read currents between 10 to 50 micro amperes;
4. An electric stove or gas stove;
5. A bottle pelastik clear, with a cut off the top;
6. Table salt, we use 2 tablespoons of table salt;
7. Water Faucet;
8. Sandpaper or can also use a wire brush;
9. Scissors (for cutting copper wire).
3.2. How to make.
1. Prepare tools and materials;
2. Wash your hands first so that no oil or grease that sticks to the copper;
3. cut the size of the copper wire with the heater panel on electric stoves;
4. Clean copper that has been cut with a wire brush or sandpaper so that no dirt or anything
else that blocks the sun's energy is absorbed;
5. Once the copper is clean and dry, place the above-mentioned copper electric stove, then
burn with the highest voltage;
6. When the copper starts to heat up you will see a pattern starting to form oxidation with
beautiful color blend of yellow and orange. Most of the copper gets hotter and display black;
7. After burning for 30 minutes, turn off the stove. Leave copper above the stove and let cool.
Allow to cool naturally because it cools too quickly would remain a black oxide coating will
stick to copper;
8. Once cooled copper (takes about 20 minutes) the majority of the black oxide will
disappear. Wash and rub gently with hands in running water to clean the small granules.
Wash gently and do not stretch as it will damage the copper oxide layer of red corpus we
need to produce energy;
9. Cut the other copper sheet size of the first copper we have had fuel. Bend both pieces
gently then input into a plastic bottle without touching each other. Copper that had been
burned is the best side to face out the bottle because the surface is smooth and clean .;
10. Attach the two alligator claws, one to the new copper and one to the copper that has been
burned. Connect the lead from the clean copper plate to the positive terminal of the meter and
copper that has been burned to the negative terminal of the meter;
11. Then, mix 2 tablespoons of table salt into the water that has been heated, stirring until the
salt dissolves in water. Put salt water into the bottle carefully, lest wet alligator claws that we
post. Salt water entered must not drown the whole copper plate, you leave at least 1 inch of
copper that is not submerged in water, it is to reduce the risk of alligator claws exposed to
water when moving the solar cell;
12. And behold the power generated.
CHAPTER IV
CLOSING
4.1. Conclusion
Solar cell capable supplied electricity to locations not served the electricity network, such as:
1. The potential use of solar energy is spread evenly so that it can be used for remote areas.
2. Solar Electricity is a quick solution, because the installation process is relatively quick to
produce electricity lighting.
3. Solar energy is very clean, because it is physically unable Meng-absorption of UV
radiation (from the sun), produces no emissions at all, does not create noise and does not
require fuel that needs to be purchased every day.
4. Solar power system has proven reliable over 50 years to support the space program, where
no other energy sources, nuclear is not too well, which can survive in extreme circumstances
in outer space.
5. Solar Panels is one tool that can harness the energy potential of solar radiation of 4.8 kWh /
m2 / day (* Data BPPT 2005) which is a large enough power potential is not maximized and
utilized in Indonesia.
6. Solar Panels have the impression of a modern and futuristic, but also has a caring
environment and a clean impression. It is suitable for the world of modern architecture that
combines the essential elements.