Download Solar Energy

Solar Energy
What is Solar Energy?
-Concepts behind solar energy
- How solar energy is used in solar cars
What is It? (solar energy)
Renewable energy source that converts
heat & light into energy
More common than we realize
Just how common is it?
The food we eat to give us energy comes
from plants that use sunlight
(photosynthesis)
We hang laundry out to dry in the sun
(using sun’s heat to do work)
Sun is responsible for making other forms
of renewable energy (biomass, wind, fossil
fuels)
How is Solar Energy used to run
a Solar Race Car?
The Basics
 The photovoltaic cell
• Building block of
solar-electric system
Let’s look at what’s happening
 Sun’s rays knock
electrons off of Atoms
 Electrons are pulled
from bottom material
to top material
 Electrons flow
through the motor
producing power
Looks a little like this…
Let’s build one…shall we?
5 components of Solar Race Car;
•
•
•
•
•
Chassis
Wheels & Bearings
Power Source
Transmission
Body/Shell
1. Chassis…
How to build the frame of the car?
-Holds all of the main parts
together
Some Possible Chassis…
 Designing & building
will involve trade-offs
 There is no one ideal
design
What to consider?
 Is your car to heavy?
 In solar cars,
efficiency is very
important
 Don’t want to waste
energy
Materials
 For solar cars,
stiffness is very
important
 E.g.. Stiff, light
materials include
styrofoam, balsa
wood and cardboard
Shape
 Paper is not stiff
 Redesigning it’s
shape, you can make
paper stiffer
Orientation
 Take an ordinary
wood/plastic ruler
• Try to bend it in both
directions
 Stiffen you chassis by
adding strips?
2. Wheels & Bearings
How to make wheels that turn
- support the chassis and allow
the car to roll forward
Wheels can be large, small,
narrow or wide…
What to consider?
 Weight Distribution
and Traction
Bearings
 Components that
allow relative motion
between the axel and
the chassis
 Holds axel and wheels
to the chassis but
reduces their friction
3. The Power Source
How the solar panel and motor work
- solar power
How does a solar panel create
power?
 The solar panel
captures energy from
the sun and turns this
energy into electrical
energy
 Electric motor uses
this energy to power
the wheels of the car
Let’s look at a mechanical
example
 Water wheel:
–
Power coming out
depends on 2 things
1. How high the water
falls
2. How much water
(how many buckets)
is poured over the
wheel
Back to the solar thing…
 Solar panel
– Very similar to water
wheel concept;
• Instead of height we
have voltage
• Instead of buckets of
water we have an
electric current
 Power = voltage x
current
Maximizing Power…
 Which car will have
more power?
 Tilt the panel towards
the sun? Add
reflectors?
4. Transmission
How to transfer power from the
motor to the wheels
There are different ways to
transfer power to the wheels
Selecting the proper gear
ratio…
 Each rotation of the
front sprocket will
make the back wheel
rotate;
– Once in combo 1
– Twice in combo 2
– 4 times in combo 3
5. Body/Shell
How the Shell effects car
performance?
& - protects passengers
- safety in case of crash
- looks
Some ideas for the Shell…
Main concept….. Aerodynamics
How much force does air have?
How about when bicycling?
Think about these for your own
design…
Fast cars shaped
to move easily
through the air
Tractor-trailer
trucks with big
air deflectors
Your Task…
 Design & Construct a
solar vehicle
 Remember to give careful
consideration to your
choice of:
Chassis
Wheels & Bearings
Power Source
Transmission
Body/Shell