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The Quiet Achiever was not a conventional car!
It was engineered in
Melbourne by brothers Larry and Garry Perkins, and was designed as a
space-framed lightweight tubular steel chassis surrounded by fibreglass flaring
to give ultimate aerodynamic efficiency. It was powered by energy generated from
the sun's rays and no other form of energy, such as a bank of batteries, which
are recharged from electrical mains (as in an 'electric' car) were used.
Larry and Garry ascertained what power could be obtained from a practical size solar module and were able to determine the aerodynamic resistance, the rolling resistance, the approximate weight of the vehicle and driver, and designed the vehicle specifically for the Perth to Sydney trip.
It was 4 metres long, 2.1 metres wide and 1 metre high (13' x 6'11" x 3'3"), and ran on four wheels, and was specially designed to provide minimum rolling resistance, and also to absorb energy if the vehicle was jarred severely, This was to prevent damage to the solar modules through flexing or twisting of the chassis.
The wheels were 70cm (27") diameter, constructed with an aluminium rim and hub, with stainless steel spokes. The ran on low rolling resistance Michelin bicycle tyres. The braking mechanism was standard bicycle brakes mounted on the four wheels. The broken spokes experienced were a result of the torque produced by the electric motor, which drove one of the wheels. This torque, the low gearing and rough roads were too much for the spokes and the best solution was keep the speed down to an average of around 25km/h.
The Quiet Achiever was constructed to carry one person, the driver, who was in a reclining position and who controlled the vehicle by tiller steering. Total weight of the vehicle was approximately 150 kilograms (330 pounds).
Twenty solar modules, each 100cm by 40cm (39" x 16") in two rows of ten (holding a total of 720 cells), covered an area of 8.5 square metres (90 square feet), and were supported on an aluminium rib-sparred lid, formed the flat top of the vehicle. The suns rays striking the top were converted to electrical power which was then fed into two conventional automotive 12 volt batteries coupled to provide 24 volts, were located in the rear of the vehicle. The stored energy provided the driving force for the vehicle. The modules were some 11 per cent efficient, that is, 11% of the total energy striking the solar panels was collected.
The solar panels were 'off the shelf' and were not specially constructed for the project.
Some 70 percent of the power delivered from the batteries transferred to the driving wheel, with the remaining power lost in cabling.
The vehicle had four gears, with a high ratio of 13:1, and a low of 33:1.
A 24 volt, 1 horsepower Bosch DC electric motor, producing 4300 revolutions, drove the rear left wheel through a variable transmission, and the speed, dictated by an ammeter, was regulated by the use of a transmission lever. Total power developed from a solar module was about 600 watts (0.8hp) and of this power, 70% was used to drive the vehicle. Top speed was around 65km/h (40mph) and the average speed across Australia over the 20 days was 24km/h (15mph). The throttle was to simply to turn a switch from 'off', to '12v' or to '24v' to turn on the power current.
When stationery the vehicle could be
positioned such that its top, hinged to the chassis, could be located at
any angle to absorb the sun's rays. Each morning and afternoon, before and
after travelling, the vehicle was positioned to fully charge the
The Quiet Achiever was constructed to carry one person, the driver, who was in a reclining position and who controlled the vehicle by tiller steering.
The tub was made of fibreglass.
Twenty solar modules, each 100cm by 40cm (39" x 16") in two rows of ten (holding a total of 720 cells),
covered an area of 8.5 square metres (90 square feet), and were supported on an aluminium rib-sparred lid, formed the flat top of the vehicle.