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SMK TAMAN SERI KLUANG
PREPARED BY;
1. NAVIN PUNJ A/L SHOMDUTT SHARMA2. MUHAMMAD FAIQ FAKHRY B MUHD YAZID3. LING JIA WEN
ACCOMPANIED BY;
EN ONN AZRI BIN PUADE
TABLE OF CONTENT
Content page
1. ABSTRACT 3
2. OBJECTIVES 7
3. SCIENTIFIC THEORIES 9
4. INNOVATIONS 12
5. FABRICATIONS 17
6. COSTS 19
7. TRIAL & ERROR 20
8. APPENDIX 21
1. ABSTRACT2
1.1 OBJECTIVES
Nowadays, in the age of science and technology, the world
is facing the threat of global warming. Greenhouse gasses and
vehicle emission not only poison our air, but in the same time
causes the thinning of the ozone layer, up in the atmosphere. The
world today is indeed addicted to fossil fuels. These limited
resources need huge energy, and cost increasingly higher to
produce fuel. Fortunately, today, there are ‘green technologies’
that can help reduce and combat the effect of global warming.
One technology in particular is the solar technology. Solar is
the sun. Our closest star, which happens to be the center of our
solar system, emits radiations. Solar radiation is radiant energy
emitted by the sun, particularly electromagnetic energy. These can
be in a form of heat and light. The light can be generated into
electricity using solar panels.
Solar car has never been a hit, since it has always been
overshadowed by gas-guzzling vehicles. Fortunately, with
technology comes improvement. Solar panels today has come a
long way, enabling engineers and scientists to produce a more
stable and consistent current from each solar panels.
1.2 DESIGN INNOVATIONS
3
These pictures are from later years of solar car race
competitions. As you can see, not that many schools really got the
concept right. As the name implies, a solar car is a type of
automobile, usually with 4 wheels and at least a seat for the driver
and more for the passengers.
This raises a question. Where is the driver’s seat?
Fortunately, with a little help from our teacher, we came up with a
design that incorporates user-friendliness.
Our solar car is designed with everything a car should have.
1.3 COST
4
A simple formula in reducing cost ; mass production. The
most mass produced car, the Ford Model T is a brainchild of a
visionary, Mr. Henry Ford. He found out that early stages of car
development costs a lot of money. Then, he decided to mass
produce his car, reaching 1 million cars in only a few years. He
was successful and forever remembered as a automotive genius.
The early stage of our solar car involves building a prototype.
The main costs are material to build the body and researching for
the best possible combination of solar panel and motor. However,
there hasn’t been any monetary issue as we had full support from
our school.
1.4 MAXIMUM SPEED VS TIME OF DAY
5
After much discussing with our teachers, we came up with a
timetable, which we use to determine the maximum speed of our
solar car in relation with the time of day. We created a table which
we can monitor the results, thus improving the angle of our solar
panel.
Date \ Time 11.00 12.00 13.00 14.00
Date 1
Date 2
Date 3
Date 4
Date 5
Maximum speed (m/s)
The table above represents our trial in determining the
maximum speed in 4 different times in the afternoon/evening. At
first, we would like to do the test in 3 days, but the cloudy and rainy
weather makes our data hard to read. So, more data can lead to a
more grouped numbers and makes averaging the speed easier for
us.
6
2. OBJECTIVE2.1 PURPOSE
The objective of this competition is to motivate Malaysian
secondary schools students in science, engineering, and
technology and to learn about solar power. Teams will design,
fund, build, and run a vehicle that is powered only by solar power.
Efficient balancing of power resources and power
consumption is the key to success during the race. At any moment
in time the optimal driving speed depends on the weather
(forecast). We were very fortunate to obtain the most efficient
balance in gear ratio and weight distribution. Our car can go quite
fast as we can get the right motor.
During the early stage of our R&D, we opted the use of a
regular DC motor. It turned out to be a high speed but low torque
motor. After discussing with our teachers, we changed the motor to
a higher torque and low speed motor. As a result, our solar car can
go at the slightest sunlight.
DC electric motor
7
2.2 SPECIFIC OBJECTIVES
The main objective of any solar car manufacturer is to build
an efficient, "winning" vehicle. Design considerations included
hundreds of tradeoffs, but certain elements are essential.
Reliability is an important design factor. A vehicle which
performed well without any major breakdowns would cover the
race distance in less time.
The overall shape of a solar car is another important design
factor. Teams had to determine how and where they would mount
the solar cells for maximum energy grain. They also had to decide
how to maintain low weight and minimize aerodynamic drag.
8
3. SCIENTIFIC THEORIES3.1 HOW DOES A SOLAR CELL WORKS?
A solar cell (also called photovoltaic cell or photoelectric cell)
is a solid state electrical device that converts the energy of sunlight
directly into electricity by the photovoltaic effect. Assemblies of
cells are used to make solar modules, also known as solar panels.
The energy generated from these solar modules, referred to as
solar power, is an example of solar energy.
Photovoltaic is the field of technology and research related to
the practical application of photovoltaic cells in producing electricity
from light, though it is often used specifically to refer to the
generation of electricity from sunlight.
Cells are described as photovoltaic cells when the light
source is not necessarily sunlight. These are used for detecting
light or other electromagnetic radiation near the visible range, for
example infrared detectors, or measurement of light intensity.
9
The solar cell works in three steps:
1. Photons in sunlight hit the solar panel and are absorbed by
semi conducting materials, such as silicon.
2. Electrons (negatively charged) are knocked loose from their
atoms, allowing them to flow through the material to produce
electricity. Due to the special composition of solar cells, the
electrons are only allowed to move in a single direction.
3. An array of solar cells converts solar energy into a usable
amount of direct current (DC) electricity.
4. The current produced turned the motor, which in turn drives
a set of gears to run the car.
10
The power of our solar panel is;
*Tests are done under maximum sunlight;
Voltage = 2.5V
The current calculation must be done in a complete circuit,
since current doesn’t flow in a load-less circuit.
According to our experiment under maximum sunlight, the
current for our solar car is; 0.075A
P = I x V
2.5V x 0.075A
P = 0.1875W
= +- 0.2Watt
→P = 0.2W, lower than the 1W regulation.#
11
V
Solar panel
Voltmeter
Sunlight
Current
4. INNOVATIONS4.1 SOLAR CELL SELECTION
Our solar car project uses a common commercially available
solar panel, which retails at RM15.00. The low cost and high
efficiency solar cell is modified. We do without the panel holder,
which further lighten our final product.
The solar panel is efficient that we need only one unit to
power up our DC motor.
4.2 SOLAR CELL CIRCUIT
The solar panel, according to the shop salesman, are 2 solar
panel in a serial connection. Serial connection limits the voltage
output, but combines the current from each of the panel. As a
result, in theory the combined solar cell voltage output is only
about 3V, but the current can go as high as 0.1amp.
A famous misconception of voltage-current
12
4.3 AERODYNAMICS
Aerodynamic is the key in designing any vehicle, especially a
vehicle built for speed. Slipstream design can helps reduce air
resistance, an archenemy of speed. A sloping nose section not
only directs air upwards, it can also provides down force, which
can helps to stabilize the vehicle in high speed.
A bubble canopy, made from high grade polyglass can also
give the car a slipstream design, thus further improving the
aerodynamics of the car.
One section which we haven’t missed is the floor. A lot of
high-performance cars, such as Ferrari and Porsche have a flat
underside of the car. This enables air to pass through and
generates negative lift. Negative lift can helps the car sticks firmly
to the ground during high speed run. We incorporated the flat
underside concept for our prototype.
Wind tunnel image of an F1 car
13
4.4 DRIVE GEAR SELECTION
The image above is our drive train. Unlike many competitors,
we used gear instead of belts. Gears are a vital piece of
engineering, and unlike belting system, slippage is not a problem
in gear systems. Power transfers efficiently, to up to 98%.
The gearing in our solar car is calculated by counting the
number of teeth on both the pinion gear and the secondary gear.
The ratio is as stated below;
Primary gear : secondary gear
8 : 30
Gear ratio 1 : 3.75
These numbers translate as ‘each rotation of the primary
(pinion) gear is equal to 3.75 rotation of the secondary gear’. This
configuration gives us the most efficient speed and torque needed
in the race.
Drive shaft
Secondary gear (30 teeth)
Pinion gear (8 teeth)
14
4.5 MATERIAL SELECTION
Thin high density polystyrene sheets.
UHU tube glue
We use the lightest material possible in order to achieve the
maximum power to weight ratio. Sir Isaac Newton famous
Newton's second law stated that the formula F = ma establishes
that as m is more, the force needed to produce the same
acceleration will also be higher. Heavy means more weight. More
weight due to more mass.
We believe by stripping down our car’s weight, we will be
able to leave the competitors in the dust.
15
4.6 TYRE SELECTION
The tyres of our solar car is salvaged from a cheap toy which
belongs to Navin’s younger brother. It is very light, made of plastic
and looks nice. Chrome wheels are always a head turner, and the
diameter is excellent for high speed. The wheels, drivetrain and
motor in our solar car are a match made in heaven.
16
5. FabricationsOur solar car begins as a sketch (refer appendix). A credit
goes to Ling Jia Wen, the artist of our group. She was able to draw
her ideas, presented and approved by our teachers.
Firstly, we cut the polystyrene sheet using a sharp knife.
Then we glued all the pieces together using UHU tube glue. The
first problem that we encounter is the wheel shaft got stuck on the
polystyrene hole. Our solution is to use a small straw to go
between the shaft and the body.
The solar panel is the last thing that we assemble on the
solar car. Our teacher, Mr Onn Azri raised a question weather to
put the panel on the back or on the front. As a proof of concept, we
run a few tests, with the panel on the front and on the rear. It
turned out that putting the panel directly on the motor makes the
car at least 1 second slower than on the front.
The next problem we face is the steering. At first, the car
tends to swerve to the right on the 3 meter mark. The solution is
simple, just like the rear wheels, we use a small straw, which we
can adjust to steer the car, and thus making the car go straight.
All the calculations and measurement are done with our
teacher. Along the way, we learned the proper way to measure
voltage and current, as well as meter connection to the circuit.
17
Voltage measurement
Current measurement
18
6. COST
Building a solar car today is quite inexpensive. The main
reason is that the technology has been duplicated by smaller
companies in China. A ‘made in China’ DIY kit can cost as low as
RM15, and can be obtained easily over the internet.
For our project car, we use the lightest material. As our
school cannot support the cost of using of carbon fibers, we use
thin polystyrene sheet. The material is very easy to cut and shape,
plus it is lightweight, perfect for making our prototype.
The total cost of our prototype is as follows;
Solar cell - RM 15.00
DC motor - RM 6.50
Wheels - RM free
Polystyrene - RM 8.00
Stationeries - RM 7.30
Total cost - RM 36.80 #
*winning the 1st place = priceless :p
19
7. Trial & errorThese results are collected in the stated date and time.
Date \ Time
In order to calculate the average speed, we take the 3
fastest times and divided them by three. All experiments are done
during hot sunny days.
Fastest speed 1 ;
Fastest speed 2 ;
Fastest speed 3 ;
Average speed ;
Fastest speed is obtained at ____________(time)
20
8. Appendix
Early stage of development
Flat underside of the car
21
Gear
Solar panel placement, optimum weight balance
22
Our solar car
23
I. FOREWORD
Tn Hj Abd Sukor Bin Salikin
The Principal
SMK Taman Seri Kluang
86000 Kluang, Johore.
First and foremost, I would like to congratulate our school’s
student for making it to the state’s level of the competition. This is
the first time ever that our students qualify to the state level in the
Science and Technology Carnival.
The solar car race competition is a part of science carnival.
These students show high interest and appreciation towards the
usage of alternative energy source, which is solar. According to
the skills and knowledge provided by our teachers, students are
able to explore science in a way they could not just by studying
theories. The competition allows our student to do practical works.
Finally, it is a hope that our school representatives are able
to go further, up to the national’s final. This will definitely do our
school proud.
______________________.
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