Sunmobile
Encyclopedia
Sunmobile was a model of a solar-powered automobile. William G. Cobb of the General Motors Corporation built and demonstrated his 15-inch long model at the 1955 General Motors car show in Chicago
on August 31, 1955. The automobile was a futuristic miniature representation to show the possibilities of solar energy. Since it was a miniature model, it could not be driven by a person.
Cobb showed and introduced the field of photovoltaics
to a car show that had over 2,000,000 visitors. At the time all automobiles were run by gasoline engines. Cobb's Sunmobile model had 12 selenium photoelectric cells on top of a balsa wood body. These solar cells were connected in series-parallel and converted the sun light directly into electricity, which in turn ran a small low-inertia electric motor. The motor rotated at 2000 r.p.m. and ran on 1.5 volts. The motor's energy in turn was transferred to the model car's drive shaft, which then in turn transferred the energy through its rear axle by a pulley
to the car's wheels which moved the car forward.
The model car balsa wood body was in five sections. It had two center sections that were hollowed out to receive a pine chassis, the electric motor, and the drive mechanism. There were precision gears from the electric motor to the wheels. They had a 3 to 1 ratio, with the smallest gear on the motor and the larger gear on the drive mechanism that propelled the rear wheels. These gears were connected with a ladder-type chain connected to their sprockets. The rubber tires, obtained at a hobby shop, were one and a half inches in diameter. The rear axle was one-eighth inch in diameter. The wiring for the solar cells to the electric motor was by standard No. 20 insulated stranded copper wire.
Chicago
Chicago is the largest city in the US state of Illinois. With nearly 2.7 million residents, it is the most populous city in the Midwestern United States and the third most populous in the US, after New York City and Los Angeles...
on August 31, 1955. The automobile was a futuristic miniature representation to show the possibilities of solar energy. Since it was a miniature model, it could not be driven by a person.
Description
The name of the 1955 General Motors Motorama car show where Cobb's model car was shown was General Motors Powerama. General Motors at the time said the car that showed futuristic capabilities was not practical because even if the solar cells ran at 100% efficiency they would only produce 12 horse-power, not enough to propel an average automobile of the time.Cobb showed and introduced the field of photovoltaics
Photovoltaics
Photovoltaics is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material...
to a car show that had over 2,000,000 visitors. At the time all automobiles were run by gasoline engines. Cobb's Sunmobile model had 12 selenium photoelectric cells on top of a balsa wood body. These solar cells were connected in series-parallel and converted the sun light directly into electricity, which in turn ran a small low-inertia electric motor. The motor rotated at 2000 r.p.m. and ran on 1.5 volts. The motor's energy in turn was transferred to the model car's drive shaft, which then in turn transferred the energy through its rear axle by a pulley
Pulley
A pulley, also called a sheave or a drum, is a mechanism composed of a wheel on an axle or shaft that may have a groove between two flanges around its circumference. A rope, cable, belt, or chain usually runs over the wheel and inside the groove, if present...
to the car's wheels which moved the car forward.
The model car balsa wood body was in five sections. It had two center sections that were hollowed out to receive a pine chassis, the electric motor, and the drive mechanism. There were precision gears from the electric motor to the wheels. They had a 3 to 1 ratio, with the smallest gear on the motor and the larger gear on the drive mechanism that propelled the rear wheels. These gears were connected with a ladder-type chain connected to their sprockets. The rubber tires, obtained at a hobby shop, were one and a half inches in diameter. The rear axle was one-eighth inch in diameter. The wiring for the solar cells to the electric motor was by standard No. 20 insulated stranded copper wire.