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					           BRIEF HISTORY
During the 1990s, regulations requiring an approach to
"zero emissions" from vehicles increased interest in new
battery technology.
Battery systems that offer higher energy density became
the subject of joint research by federal and auto industry
scientists.
Solar cars were first built by universities and
manufacturers. The sun energy collector areas proved to
be too large for consumer cars, however that is
changing.
Development continues on solar cell design and car
power supply requirements such as heater or air-
conditioning fans.
  Initial steps to start a solar car
                project
Building a solar car is a very ambitious goal, but one that
is achievable through hard work and commitment.
 One of the first things to do is to organize a group of
people interested in building a car, and planning a
specific goal..
You will need a core group of fundraisers who are willing
to spend the year making presentations to businesses
and speaking to individuals at their home.
You will also need to assess what materials and tools
you need and get several people focused on building the
car itself.
It may be a difficult road the first year, but the things you
learn along the way will last a lifetime!
              Introduction

Solar cars are powered by the sun's energy.
 The main component of a solar car is its solar
array, which collect the energy from the sun and
converts it into usable electrical energy.
The solar cells collect a portion of the sun's
energy and stores it into the batteries of the
solar car.
 Before that happens, power trackers converts
the energy collected from the solar array to the
proper system voltage, so that the batteries and
the motor can use it.
             Introduction

After the energy is stored in the batteries,
it is available for use by the motor & motor
controller to drive the car.
The motor controller adjusts the amount of
energy that flows to the motor to
correspond to the throttle.
The motor uses that energy to drive the
wheels.
BASIC LAYOUT
      Components of a solar car
Solar Array and Power Trackers
• A solar array created from individual solar cells as opposed to one
  made of prefabricated solar panels.. Each solar cell should produce
  .5 volts at about 3 amps at peak sunlight.
• The number of cells to use depends on their size and the allowable
  solar area per Winston rules. Solar cells should be wired in series
  on a panel and should be divided into several zones.
• For example, if you have 750 solar cells, you might want to wire 3
  sets of 250 cells, each zone producing about 125 volts. If one zone
  fails, two other zones are still producing power.
• The solar array voltage does not need to match the system voltage
  of the motor if you use power trackers.
• Power trackers convert the solar array voltage to the system
  voltage. They are essential in a solar car.
                   Batteries

The batteries store energy from the solar array and
makes them available for the motor's use.
Flooded-cell batteries are the standard automotive
batteries filled with liquid sulfuric acid.
They are preferred because they can be overcharged
without risk of blowing up, but they weigh more than gel-
cell batteries.
Gel-cell are sealed and lightweight, but when charging
the batteries, check the battery voltage often.
The number of batteries to choose depends on the motor
(system) voltage.
         Motor & Controller

Motor and controller setups allow for
regenerative braking, which allows the solar car
to put energy back into the batteries when going
downhill.
For the beginning team, DC brush motors would
be sufficient to get a solar car up and running.
 Controllers usually drive a particular motor.
Once you choose the motor that suits your
needs, the same vendor would most likely have
a matching controller.
     Steering & Suspension

We strongly recommend front wheel steering as
it tends to be more stable and safer.
 A solar car uses energy frugally if it is to be
competitive.
 If there are two front wheels, it is therefore
advisable to work out the geometry
The only advice we can offer with respect to
suspension is that it should be soft enough to
protect the car and solar array from unnecessary
jolts and firm enough to provide a stable ride.
                 Brakes

Disc brakes are desirable as they are
predominantly hydraulic.
Having hydraulic lines running to the wheels can
be easier than mechanical brake arrangements.
 The most significant problem with disc brakes is
that the brake pads do not back away from the
brake rotors when pressure is released, they just
relieve braking pressure.
Go kart now have brake calipers that are spring
loaded to move the pads away from the rotors.
We have found these very worthwhile.
               Tires & Hubs

Tire selection will affect rolling resistance which affects
how far the solar car will travel with the energy available.
Tires with thicker rubber and wider tread tend to have
higher rolling resistance
Thinner tires with higher pressure have less rolling
resistance, but are more susceptible to flats.
Bearing resistance can be reduced by light minimal
lubrication.
 Bearing seals can be cut away at the contact lip to leave
most of the seal protection while removing most if not all
seal drag.
            Solar array

The solar array consists of hundreds of
photovoltaic solar cells converting sunlight
into electricity.
In order to construct an array, PV cells are
placed together to form modules which are
placed together to form an array.
The larger arrays in use can produce over
2 kilowatts (2.6 hp).
Solar array
        HOW SOLAR ARRAY ARE
             MOUNTED
The solar array can be mounted in several ways:
• horizontal.
• vertical..
• adjustable. Free solar arrays can often be tilted around the axis of
  travel in order to increase power when the sun is low and well to the
  side.
• integrated. Some vehicles cover every available surface with solar
  cells. Some of the cells will be at an optimal angle whereas others
  will be shaded.
• trailer. Solar trailers are especially useful for retrofitting existing
  vehicles with little stability, e.g. bicycles. Some trailers also include
  the batteries and others also the drive motor.
• remote. By mounting the solar array at a stationary location instead
  of the vehicle, power can be maximised and resistance minimized.
  The virtual grid-connection however involves more electrical losses
  than with true solar vehicles and the battery must be larger.
How can solar panels power a car?
 Solar cars can accomplish power through
 photovoltaic cells (PVC).
 PVCs are the components in solar paneling that
 convert the sun's energy to electricity.
 They're made up of semiconductors, usually
 made of silicon, that absorb the light.
 The sunlight's energy then frees electrons in the
 semiconductors, creating a flow of electrons.
 That flow generates the electricity that powers
 the battery or the specialized car motor in solar
 cars
How can solar panels power a car?
How can solar panels power a car?
    Pros and Cons of Solar-powered
                Cars
•
    While they are still a possibility, solar-powered cars are a long way off.
    There are a number of practical problems with solar-powered cars.
    Most importantly, it's difficult for the car's solar array to gather enough
    power to move the car. That's why most solar race cars only carry one
    person -- the extra weight of a passenger would tax the car's power.
•   The way solar cars gather and store power is also a big issue. Solar
    power makes sense for buildings, the space station and even satellites
    because those structures are regularly exposed to the sun. These
    applications also have the ability to use batteries to store the energy
    the sun generates. A large battery pack -- with enough storage to
    power the car from sunset to sunrise -- would make an electric car far
    too heavy, so a solar-powered car must be in the sun at nearly all
    times to be effective. That means solar-powered cars aren't very
    practical if you're in a tunnel, a covered parking garage or even if it's
    cloudy. Building rooftops, the space station and satellites also have
    the space for much bigger, more powerful solar arrays that allow them
    to gather more energy. For a car to harness the equivalent amount of
    energy, the vehicle proportions would have to be huge.
  Pros and Cons of Solar-powered
              Cars
• Beyond that, there's the high cost of the solar panels. The type
  of solar panels used on solar-powered cars is very expensive.
  In fact, a competitive solar-powered race car can cost hundreds
  of thousands of dollars -- and as we've already mentioned,
  currently, there's not a very good way to make the car useable
  when the sun isn't out.
• With that said, all of the hard work that's gone into solar-
  powered cars hasn't been a waste. The information that
  engineers have learned from building solar-powered cars has
  guided their work in other areas. This includes aiding in the
  development of smaller, more efficient solar arrays, as well as
  the development of solar panels that can be attached to
  gasoline-powered cars to increase their efficiency and
  decrease their fuel consumption. While solar-powered cars
  really aren't a possibility in the near future, there's no reason to
  completely write off the idea. With continued research, they
  may eventually become a more practical solution
             Practical Panels

• You may not have to wait too long to get your
  hands on a car that's at least partially solar-
  powered. There's speculation that the 2009
  Toyota Prius will have a solar panel on the
  rooftop that could help power the vehicle's air
  conditioner and other electrical accessories.
  General Motor's Cadillac Provoq concept, which
  debuted at the Consumer Electronics Show in
  Las Vegas, Nev., also has a rooftop solar panel.
  This type of sparingly applied solar technology
  may not be too far from the showroom floor.
PROTOTYPE OF SOLARCAR
          Rising funds

Public Presentations
From big industries

From government organisations
From International research agencies
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posted:5/12/2011
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