Technological Trajectories and the Human Environment (1997) / Chapter Skim
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Elecktron: Electrical Systems in Retrospect and Prospect
Elecktron: Electrical Systems in Retrospect and Prospect
Pages 110-134
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From page 110... ...
Elektron: Electrical Systems in Retrospect and Prospect JESSE H AUSUBEL AND CESARE MARCHETTI And I saw something like the color of amber, like the appearance of fire round about enclosing it; from what appeared" to be his loins upward, andfrom what appeared to be his loins downwards, I saw what appeared" to be fire, and there was a brightness round about him.
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From page 111... ...
Upon awakening, the mummy observes to the Americans gathered round him, "I perceive you are yet in the infancy of Galvanism." Later in the nineteenth century the Swedish playwright August Strindberg wrapped himself in currents to elevate his moods and even gave up writing to pursue electrical research until he badly burned his hands in an ill-planned experiment. Popular imagery notwithstanding, the high-voltage, low-current electrostatic phenomena were at the core of electric research until only about 1800, when Alessandro Volta announced his invention of the battery.
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From page 112... ...
As we shall see, once the interface between mechanical and electrical power had been invented, the niche for expansion proved immense.2 POWER FOR THE WORKSHOP Since the Middle Ages, water wheels had provided the primary drive for grinding grain, fulling cloth, working metal, and sawing wood. But mechanical power drawn from water or wind did not permit action at a distance, except through even more mechanical devices.
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From page 113... ...
The original Edison systems were based on low-voltage direct current (dc) , which suffered drastic energy losses over distance.
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From page 114... ...
NOTE: The main figure presents the two sets of data shown in the inset panel fitted to a linear transform of the logistic curve that normalizes each process to 100 percent, with estimates for the duration of the process, its midpoint, and saturation level indicated. DATA SOURCE: Pennsylvania Power and Light (19401.
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From page 115... ...
Although various factors lower actual line capacity in practice, this indicator provides a consistent measure of power capacity for analysis of long-term trends.5 The maximum line capacity grows in two waves, one centered in 1921 and the second fifty-four years later in 1975. We label the first wave "Steinmetz," for Charles Proteus Steinmetz, the founding leader of the engineering department of the General Electric Company (GE)
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From page 116... ...
At peak times operators experience the most rapid change and customers suspect the operators' ability to handle it. Dunng the second wave, annual growth in consumption peaked in the 1950s and 1960s at more than 10 percent per year for many US utilities.
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From page 117... ...
Italy buys from France the equivalent production of six 1-gigawatt nuclear reactors either via direct high-voltage lines or through Switzerland. Electricity trade could form a significant component of international payments over the next fifty to one hundred years, requiring reorganization and joint international ownership of the generating capacity.
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From page 118... ...
Generators with low capital cost and high variable cost combine with base-loads plants with high capital cost and low variable cost to determine the current usage level. Although the utilization factor surely has a logical upper limit quite below 100 percent, even with high-voltage lines having continental reach, a 50-percent national average appears low, notwithstanding scorching August afternoons that demand extra peak capacity.
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From page 119... ...
Net generation in 1993 was 2,883 terawatt hours. Projecting electricity demand matters because it influences investments in capacity.
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From page 120... ...
AUSUBEL AND CESARE MARCHETTI 100% a, ._ a, ~ 80% ._ c) 111 60% ._ In 4, o I o 40% 20% a, AL Urban .~ .
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From page 121... ...
The most wanted environmental culprit is carbon, and so the main environmental challenge for electricity may be summarized by the measure of the carbon intensity of electricity production, for example, the ratio of carbon by weight to kilowatt hours generated.7 In the United States, this ratio fell by half between 1920 and 1940, from about 500 metric tons of carbon per gigawatt hour produced to about 250. Since the 1940s, the US ratio has fallen below only about 200 metric tons per gigawatt hour and has remained rather flat in recent decades because coal has gained markets in electric power plants, offsetting efficiency gains in the operations of the plants as well as gains in terms of reductions that oil and especially gas would have contributed.
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From page 122... ...
In this regard, direct current, now ultra-high, may have a second life as a bulk carrier aided by relatively cheap electronics, such as thyr~stors, which are capable of transforming all types of units of electricity into all others. Burying power lines might beautify the landscape, as well as lessen fears about the health effects of electromagnetic fields.
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From page 123... ...
Electrical energy is glorified as the purest form of free energy. In fact, the heat value of other fuels when they burn also corresponds to free energy.
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From page 124... ...
Supercon ductivity, when it permits high magnetic fields, can lead to compactly designed motors with broad applications and very low energy losses. The proliferation of numerous micro-machines will of course tend to raise electricity demand, partially offsetting the efficiency gains they offer.
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From page 125... ...
One attraction is that the final user immediately pays the capital cost. In any case, the breakthroughs may come instead on the side of the consumers.
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From page 126... ...
Amusement parks such as Luna Park and Dreamland at Coney Island in New York drew millions of paying visitors to admire the architectural sculptures of light. Edison's 1879 incandescent lamp was a trifle inferior to the arc in light quality and efficiency but was immensely more practical.
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From page 127... ...
Toward the end of the last century electric motors for vehicle engines attracted much inventive action. Edison and Ferdinand Porsche produced sophisti
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From page 128... ...
To go to very high passenger fluxes over longer distances, one would need to go to aerial configurations of which even the most daring air-transport planners do not chance to dream: flocks of airplanes of five thousand passengers each taking off and landing together like migrating birds. For intense connections linking large cities with peak fluxes around ten thousand passengers per hour, a solution is emerging that matches system requirements: the magnetically levitated (maglev)
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From page 129... ...
Power demand is proportional to train speed and moves into the gigawatt range in the central section; however, with local storage (a few kilowatt hours per meter) the external electric power networks would see only the need to make up losses.
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From page 130... ...
In the first, the United States attained system saturation in the 1930s at about 1,000 kilowatt hours annual consumption per residential customer, 200 gigawatt hours of total annual use, 40 gigawatts of installed capacity, and 20 percent of primary fuels producing electricity. In the second wave, we have reached 10,000 kilowatt hours per residential customer, 3,000 gigawatt hours of total use, 800 gigawatts of installed capacity, and about 40 percent of fuels producing electricity.
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From page 131... ...
Introducing electricity into production raised the rank of workers from sweating robots to robot controllers. The process can be generalized, with humanity at leisure or at work giving orders to its machines by voice or a wink of the eye.
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From page 132... ...
A train of 200 metric tons accelerating at 0.5 g has a pull force (drag) of 1,000 kilonewtons, which over a stretch of 500 kilometers corresponds to 5 x 101 l joules, or approximately 140,000 kilowatt hours.
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From page 133... ...
Technological Forecasting and Social Change 18:267-282. Marchetti, C
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From page 134... ...
1994. Statistical Abstract of the United States.
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