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Rabu, 03 Juli 2013

Early Automobile History -- Choices Made: Competition from Steam Engines and Electric Motors

Choices Made:  Competition from Steam Engines and Electric Motors
            The early designs of the internal combustion engine were primitive to say the least, and thus these power plants were anything but reliable and smooth running. At the turn of the century steam cars dominated the automotive field. An alternative was the electric car; but they were expensive and limited in range and speed. As it turned out, there was a short window of time in which these three technological rivals were engaged in a contest that revolved around which would be the chief power source for this new form of flexible and personal transportation, the automobile. The end result would have enormous consequences for the remainder of the twentieth century, economically and environmentally. As Tom McCarthy has pointed out, during the first decade of the twentieth century, a number of experts warned of the environmental consequences of ICE-powered vehicles, including the issues of oil depletion and toxic exhausts. However, McCarthy contends that the widespread adoption of the automobile by a consuming public allayed concerns at a time when adjustments could have been far more easily made than those that we, in the early twenty-first century, are now making.21
            Steam had a long history going back to the eighteenth century as the chief power source for factories, railroad locomotives, and electrical generation. For automobiles, steam engines were quieter than internal combustion. With fewer moving parts, steam engines had been manufactured for generations, and with less exacting tolerances. In addition, a steam engine had remarkable torque, especially from a dead stop. Steam pressure could be built up and stored, to be released at full force on demand. An internal combustion engine must turn within a narrow range of revolutions per minute to operate efficiently. Additionally, as anyone who has looked at a schematic of a transmission or differential knows, gears and small parts result in a power transmission system that can only be deemed ingenious to the mechanically uninitiated. Moreover, in the cylinder of a gas engine, the greatest force is exerted at the explosive instant of ignition, with the power dissipating as the piston completes its stroke. But in the cylinder of a steam engine, the steam enters, expands and continues to push for as much as 90 percent of the stroke.
            Steam engines had both limitations and advantages.22 With its extensive piping and metalwork, a steam car was heavier than an ICE car of comparable horsepower. Steam engines ran at lower thermal efficiencies than gas engines, losing much of their heat to the atmosphere. And while the working parts of a steam engine were quite simple and durable, the ancillary equipment – boiler, burner, and all manner of pumps, valves, and gauges – were dauntingly complex, demanding constant attention and maintenance. Most critically, the popular steam cars of the early 1900s – Stanley, White, and Locomobile – took 10 to 30 minutes to work up adequate steam pressure from a cold start and then had to stop for water every 30 to 100 miles. ICE-powered cars started faster and had greater range, an advantage in rural areas where service stations were sparse.

 1902 White Steam Car
1904 White Steam Car

            After the turn of the century, steam car technology remained essentially stagnant for years until Abner Doble introduced advanced designs, while ICE-powered cars quickly improved. By the end of the first decade of the twentieth century, steam cars were technologically obsolete and economically unviable. Given these winds of change, White and Locomobile both converted to internal combustion by 1910, leaving only Stanley to fill a market with a curiosity that in recent times has been resurrected in as an interest in “buff” circles by car collector and comedian Jay Leno.

            In addition to the ICE- and steam-driven automobiles, there were also electric models at the turn of the century, partly the consequence of work by Thomas Edison and others related to improved battery designs.23 Electrics had several distinct advantages. They were especially attractive to those in the taxi business and women who wished to avoid the crank starting, noise, vibration, and pollution of ICE-powered vehicles. Low-end torque characteristics of electric motors ensured quick starts. However, in the early twentieth century any advantages were greatly outweighed by the many serious liabilities. Electrics were far more expensive than the gasoline automobile to manufacture and about three times more expensive to operate. Batteries could weigh a ton or more. There was the ever-present wire or cord that had to connect to a discharged electric car. As late as 1910, their range was only 50 to 80 miles on a battery charge, charging facilities were virtually nonexistent outside large cities, the storage batteries of the day deteriorated rapidly, and its hill climbing ability was poor due to excessive weight of the batteries for the horsepower generated.24 These relative liabilities have persisted to the present, despite recent improvement in storage batteries.




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