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OCR for page 110
Technological Trajectories and the Human Environment. 1997.
Pp. 110-134. Washington, DC: National Academy Press.
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.
Ezekiel 1:27 (circa 595 B.C.)
In the ancient world, electrum (Hebrew) or electron (Greek) was the material
amber. Amber, when rubbed and electrified, preferably with cat fur, moved and
lifted dust specks and small objects. The Greeks first identified electricity by its
godlike capacity for action at a distance. This capacity and its control have been
and will continue to be the trump cards in the invention and diffusion of electric
machinery.
While its power and magic are old, electricity as an applied technology is
young, with a history of barely more than a century. Two thousand five hundred
years passed between Ezekiel and Thomas Edison. Today the electrical system
can place power in precise positions in space with an immense range of capacity,
from nanowatts to gigawatts. This spatial fingering is made possible by electrical
conductors that are immersed in insulating space or solids. The conductors, which
are basically metals, are impenetrable to electric fields and can modify and draw
them into long thin threads reaching an office, home, or the memory cell in a
computer chip.
Electromagnetic waves, as well as wires, transport electrical energy into
space. Microwave guides and optical fibers resemble wires fingering into space.
Efficient interfaces between the two modes of transport have developed, greatly
extending the panoply of gadgets that transform electricity into useful actions.
110
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ELEKTR ON: ELECTRICAL SYSTEMS IN RETROSPECT AND PROSPECT
111
Electrical technology is one of the few technologies that emerged straight
from science and organized research. The lexicon of electricity ohms, amperes,
galvanometers, hertz, volts is a gallery of great scientists of the eighteenth and
nineteenth centuries. Applications of electricity were the subject of the first sys-
tematic industrial research laboratory, established in 1876 by Edison in Menlo
Park, New Jersey. There, Edison and his colleagues made the phonograph in
1877, a carbon-filament incandescent lamp in 1879, and myriad other inventions.
The earliest attempts to apply electricity came from laboratories studying
electrostatic phenomena. Medicine, always curious to test new phenomena in the
human body that promised healing or strength, led the way. Many claims sprang
from the spark, shock, and sizzle of electrostatic phenomena. Eighteenth-century
scientists reported that electric charges made plants grow faster and that electric
eels cured gout. They sent electrical charges through chains of patients to conquer
disease and, as among the clientele of Dr. James Graham's fertility bed in Lon-
don, to create life. C. J. M. Barbaroux, later a leader of the Girondist faction in the
French Revolution, enthused in 1784:
O feu subtil, ame du monde
Bienfaisante electricity
Tu remplis ['air, la terre, l'onde,
Le ciel et son immensite.i
Electricity brought to life the subject of Dr. Frankenstein's experiments in
Mary Shelley's famous novel, published in 1818. An application of electricity
also vitalized the ancient Egyptian in Edgar Allan Poe's 1845 story "Some Words
with a Mummy" (Poe, 1976~. Upon awakening, the mummy observes to the
Americans gathered round him, "I perceive you are yet in the infancy of Galva-
nism." 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 ex-
periment.
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. Volta introduced the
more subtle low-voltage, high-current game of electrodynamics. Twenty-five
years linked the flow of electric currents to the force of electric magnets. Another
twenty-five years bound the two productively into the electric dynamo and mo
tor.
Among the key figures in the electromechanical game was an American,
Joseph Henry, who, with the Englishman Michael Faraday, contributed a series
of discoveries leading to practical electric generators. Tracing a bright path back
to Benjamin Franklin, electricity was one of the first fields of research in which
the United States assumed a leading role, and one of the first technologies to
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2
JESSE H. A USUBEL AND CESARE MARCHETTI
diffuse earliest in America. As we shall see, once the interface between mechani-
cal and electrical power had been invented, the niche for expansion proved im-
mense.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. These could become sophisticated and
baroque. For example, a cable system spread 1 megawatt of mechanical power
from the falls of Schaffhausen, Switzerland, to the industrial barracks around
them. The mechanically drawn San Francisco cable cars continue to delight
visitors but only travel a distance of one or two kilometers.
Powered by water, workshops had to be riparian. "Zavod," the Russian word
for a plant, literally means "by the water." Ultimately, steam detached power
from place. Over a period of decades, steam engines overtook water wheels. In
America, steam needed one hundred years to supersede water. Though we recall
the nineteenth century as the age of steam, water did not yield first place until
1870. The primacy of steam in America would then last just fifty years (Figure 11.
At first, steam preserved the layout of the factory. It simply provided more
flexible and dependable mechanical energy. The small early steam engines usu-
ally operated individual devices. A leap forward came with the advent of the
single, efficient, central steam station to serve all the machinery inside a plant.
Pulleys rotating above the heads of the workers provided power for their diverse
machines via vibrating and clapping belts. But the network of beams, blocks,
cords, and drums for transmitting the steam power to the machinery on the floor
encumbered, endangered, and clamored.
The electric motor drive, which emerged around 1890, revolutionized the
layout of the factory. The first era of electrical systems commenced. The steam
engine now ran an electric generator that penetrated the factory with relatively
inconspicuous copper wires carrying electricity, which in turn produced me-
chanical energy at the point of consumption with an electric motor. Here was the
seed of modern manufacturing. The electric motor drive permitted the factory
machines to be moved along the production sequence, rather than the reverse.
One might suppose that the superior electric transmission, with a generator at
one end and motors at each machine, would quickly supplant the old mechanical
system. In fact, as Figure 1 shows, the process required fifty years. Resistance
was more mental than economic or technical. In 1905 the influential American
historian and journalist Henry Adams chose the images of the Virgin and the
dynamo around which to write his autobiography (Adams, 1918~. The dynamo
symbolized the dangerous, inhuman, and mindless acceleration of social change.
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ELEKTR ON: ELECTRICAL SYSTEMS IN RETROSPECT AND PROSPECT
1~
107
5 1 o6
to
o 1 05
I
104
103
1o1
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~ = ,~ ~rrh
- Water .7
-- Electric//`lnternal
~ Combustion
1880 1900 19201940
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·~\
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1900 1920 1940
1 880
90%
50%
o
._
_
U
10% ~5
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113
FIGURE 1 Sources of power for mechanical drives in the United States. NOTE: The
upper panel shows the absolute horsepower delivered by each type and their sum. The
lower panel shows the fraction (F) of the total horsepower provided by each type, accord-
ing to a logistic substitution model. DATA SOURCE: Devine (1983, Table 3, p. 351~.
POWER FOR THE REGION
By the time arcs and lamps emerged from Mr. Edison's workshops, the
generator could illuminate as well as grind, cut, and stamp. But the paradigm of
the single generator for the single factory was soon superseded by the idea of a
generator, or, better yet, a power plant, serving an entire community.
At first, electric companies were necessarily small. Technology for the trans-
port of electricity particularly limited the scale of operations. The original Edison
systems were based on low-voltage direct current (dc), which suffered drastic
energy losses over distance. Each piece of territory thus required its own com-
pany, and founding a new company meant filling a piece of territory or market
niche.
Consider eastern Pennsylvania, a coal-and-steel region where some of the
earliest Edison utilities began (Figure 2~. Entrepreneurs swarmed the area to
spread the successful innovation. About 125 power-and-light companies were
established between the middle 1880s and early 1920s, with 1897 being the year
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4
JESSE H. A USUBEL AND CESARE MARCHETTI
1o2
1o1
ilk
~ 10°
LL
10-1
10-2
l
125 - -
Am /
100 J f
_ 75 - ·t ~-
50 J ~
25 ,
A.
o . , ..~ ,
- 1850 1875 1900 1925 1950
7~ .Y
1 1 · 1 1
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· / /124
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1 897~/
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/ 1914
'/~=25y
1850 1875 1900 1925 1950
Year
99%
90%
-
50% °
IL
10%
1%
FIGURE 2 Founding and consolidation of electric companies in the United States.
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.
Of peak corporate fertility. The rush to form companies was a cultural pulse,
diffused by imitation.3
The evolution of technology to transport electricity, combined with the in-
crease in the density of consumption (kW/km2), made higher transmission volt-
ages economical and progressively coalesced companies. The key technology,
first explored in the 1880s by the inventor Nikola Tesla, was alternating current
fact, which could be raised in voltage through transformers and then transmitted
long distances with low losses. The merger wave crested in 1914. By 1940 the
resulting process left only Pennsylvania Power and Light in operation.
When companies cover a geographical space, their natural tendency is to
coalesce, like soap bubbles, especially if a technology permits the larger scale
physically and encourages it economically. Several non-technical factors, includ-
ing government and consumer fears about monopoly, can set limits on scale.
Early in the century, Samuel Insull's "electricity empire," centered in Chicago,
evoked public regulation, which became normal for the industry. Rapid growth
and change usually elicit external regulation. Still, the systems grow in the long
run, as we shall see.
In the provision of electric power, the overriding independent variable is
spatial energy consumption. Its increase leads to higher-capacity transport lines
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ELEKTR ON: ELECTRICAL SYSTEMS IN RETROSPECT AND PROSPECT
1o2
1o1
10°
1 o 1
1o2
1 1 1 1
/88 1400(~88)
· 192 ~Starr Wave
/ Steinmetz Wave ~9/ ~
~ 1975
/ At=26y / At=27y
1900 1920 1940 1960 1980 2000
Year
115
99%
90%
-
IL
-
50% .°
10%
1%
FIGURE 3 Capacity of top US power lines. NOTE: The units are kV2/l,OOO a rough
measure of power capacity. This figure as well as Figures 4, 6, and 8 show a two-phase
process analyzed as a "bi-logistic" normalized with a linear transform. In essence, one S-
shaped growth curve surmounts another. The actual values are the sum of the two waves,
once the second wave is under way (see Meyer, 1994~. DATA SOURCE: Edison Elec-
tr~c Institute, Washington, D.C.
using higher voltage, making it possible to transport energy over longer distances
with generators having higher power. This "higher and higher" game led the
United States from the 10-kilowatt generator of Edison to the 1-gigawatt genera-
tors of today, one hundred thousand times larger.4
In fact, the expansion divides into two eras, as we see in Figure 3, which
shows the evolution of the maximum line capacity of the US electric system. For
the line-capacity indicator, we take over time the square of the highest voltage
that is operational. Although various factors lower actual line capacity in prac-
tice, 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) and a symbol of the fruitful interaction of mathematical physics and electri-
cal technology (Hammond, 19243. Following the pioneering work of Tesla,
Steinmetz began investigating the problems of long-distance transmission and
high-voltage discharges around 1905. The spectacular success of GE in subse-
quent decades testifies to the timeliness of Steinmetz's innovations. New alter
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6
JESSE H. AUSUBEL AND CESARE MARCHEITI
nating-current systems and related gadgets made huge profits for GE and the
other leading equipment supplier, Westinghouse, and incidentally killed many
small-scale utilities, as in Pennsylvania.
The second pulse of growth in line voltage reaches a temporary ceiling at
about 1.S megavolts. Interestingly, the stretches of innovative activity, as mea-
sured by the interval to achieve 10 to 90 percent of the system development,
cover only about half the time of electncity's waves of growth. Two to three
decades of rapid expansion are digested in a comparably long period of stability
and consolidation, a frustrating cycle for engineers. Again the limit may not be
technical or economic, but social. Society tailors the expanded system to fit its
norms for safety and harmony. One constraint is available nghts-of-way, which
are very limited at present.
Because the area of the United States is constant and filled by the electrical
network, total generating capacity approximates the spatial density of consump-
tion. The growth in installed generating capacity also splits into two pulses,
centered around 1923 and 1971 (Figure 4~. 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. The system in the
Northeast blacked out one day in November 1965, prompting regional power
pooling arrangements. To address concerns about the reliability of the entire
network, the industry consorted to form the Electnc Power Research Institute,
1o2
-
~101
._
-
~.
_ ~ 10°
_
~ I,
25
~5 1 0-1
In
-
_ 1 1 1 1 ~1 1 1 1
35GW ~;
.Y
·/
- ~ 1923
/
- . /
~1 , 1
1o2
1900 1920 1940
on/
TV
99%
730 ~ ~ 35) GW/
A/
GO/
/
An_
A/
Ha
~ 1971
go%
so%
in
10%
1 1 1 11%
1960 1980 2000
Year
FIGURE 4 Installed electric generating capacity in the United States. DATA SOURCES:
US Bureau of the Census (1978a, b; 1981; 1984; 1986; 1989; 1991; 1992; 19941.
OCR for page 117
ELEKTR ON: ELECTRICAL SYSTEMS IN RETROSPECT AND PROSPECT
117
which opened its doors in 1973 under the leadership of Chauncey Starr, for whom
we name electricity's second wave (Starr, 1995~.
The current pulse of growth in US generating capacity reaches a ceiling
around 765 gigawatts. The actual system growth has exceeded 90 percent of the
niche, which in our view explains the recent slowdown in the building of power
plants, nuclear or other, in the United States. The system anticipated the growth
in demand that is tuned to economic development and technological diffusion,
boxed into the long, roughly fifty-year economic cycles that have characterized
the last two hundred years (Marchetti, 1986~. At the end of the cycles, demand
lags and overcapacity tends to appear.
Will the higher-and-higher game resume? In both line voltage and generat-
ing capacity, the growth in the second electrical wave exceeded the first by more
than an order of magnitude. If the pattern repeats, the increase in electricity
consumption will lead to ultra-high voltage lines (for example, + 2 megavolts)
with higher capacity (for example, 5 or 10 gigawatts) and continental range. The
great advantage of continental and intercontinental connections is that standby
reserves and peak capacity can be globalized. The worldwide load would be
smoothed over the complete and immanent solar cycle. Generators could also
become very large, with according economies of scale.
If the system evolves to continental scale, the much-discussed superconduc-
tivity at room temperature might not revolutionize transmission after all. Energy
lost in transport and distribution is a stable 10 percent, a huge amount in absolute
terms, but too small to change the basic economics if 2-megavolt lines cover the
continents. Superconductivity could, however, bring about a revolutionary drop
in the size of machinery, thereby permitting the construction of units of larger
capacity.
Continental scale surely means increased international trade in electricity.
All territory looks the same to electricity. If available technology is employed,
electricity will stream across borders despite the political barriers that typically
impede the easy flow of goods and ideas. Today Europe exchanges electricity
almost freely. Italy buys from France the equivalent production of six 1-gigawatt
nuclear reactors either via direct high-voltage lines or through Switzerland. Elec-
tricity trade could form a significant component of international payments over
the next fifty to one hundred years, requiring reorganization and joint interna-
tional ownership of the generating capacity. Electricity trade between Canada
and the northeastern United States already elicits attention.
UTILIZATION AND CAPACITY
The utilization factor of generation plants counts heavily in the economy of
the system and indicates the quality of its organization. The US electric industry
searched successfully between 1910 and 1940 for efficient organization, notwith-
standing the Great Crash of 1929, as the average annual utilization climbed from
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118
JESSE H. A USUBEL AND CESARE MAR CHETTI
two thousand to above four thousand hours, a utilization rate of about 50 percent
(Figure 5~. The rise owed to spatial integration and the reduction of reserves
consequent to the introduction of high-capacity transport lines with increasing
operating voltage as well as the coordination of network dispatch to use plants
more effectively.
Since 1940 the system appears to have fluctuated around a utilization rate of
50 percent. 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.
Breaking the 50-percent barrier must be a top priority for the next era of the
industry. Otherwise, immense capital sits on its hands. One attractive way to
make electric capital work around the clock would be to use plants at night. The
mismatched timing of energy supply and demand existed when water power
dominated. Pricing, automation, and other factors might encourage many power-
consuming activities, such as electric steel-making, to go on the night shift.
Nuclear heat, generating electricity by day, could of course help to make hydro-
gen at night. The ability to store hydrogen would make the night shift productive.
The nearness of overcapacity in the electrical system also creates suspicion
that forecasting within the sector has not been reliable. Analyses of projections of
total electricity use made by the US Department of Energy and others fuel the
suspicion. Reflecting a period when electricity consumption had doubled in spans
8,000
6,000
2,000
50% Utilization
W~, :'
1900 1920 1940 1960 1980 2000
Year
FIGURE 5 The rate of utilization of US electric generating plants. DATA SOURCE:
US Bureau of the Census (1978a, b; 1981; 1984; 1986; 1989; 1991; 1992; 19941.
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ELEKTR ON: ELECTRICAL SYSTEMS IN RETROSPECT AND PROSPECT
1o2
-
o
._
Q
^
o _ ~ O
IL
v
._
-
-
it
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99%
I ~ ~ i ~ - i
- 190 TWhr/ 2730
- / (~190)TWhr /
/ /
~ /O°°O° ~
1929 ~^ OOOo 197~:
/ ~
/ ~..~
/o°
10-2 1 1 , ~, I , 1 , 1%
1900 1920 1940 1960 1980 2000
Year
1960 1 980
90%
50% 0
_
"n
1 non
FIGURE 6 Total US electric consumption. NOTE: Here and in Figure 8 the empty
circles indicate periods of overlap in the sequential growth waves. Assigning the exact
values to each wave during the periods of overlap is somewhat arbitrary. DATA
SOURCE: US Bureau of the Census (1978a, b; 1981; 1984; 1986; 1989; 1991; 1992;
19941.
Of ten years, in 1978 federal officials projected an increase by 1990 from 2,124
terawatt hours to 4,142 terawatt hours.6 The actual level for 1990 was 2,807
terawatt hours.
Can we do better? Fitting the data for total utility electric use to our model
with data through 1977 yields an estimated level of about 2,920 terawatt hours for
the growth pulse now ending (Figure 64. Net generation in 1993 was 2,883
terawatt hours. Projecting electricity demand matters because it influences in-
vestments in capacity. Accurate projections might have lessened the pain for the
utilities, which ordered and then canceled plants; the equipment suppliers, who
lost the orders; and consumers, who ultimately pay for all the mistakes.
POWER FOR THE HOME
As suggested earlier, electricity is a spatial technology. Conquering a terri-
tory means connecting with potential users. We tend to think that almost every-
one was connected soon after the first bulb was lit, but in fact the process ex-
tended gradually over fifty years and culminated even in the United States only in
mid-century (Figure 7~. Although slowed by the Great Depression, non-rural
hookups reached 90 percent of the market by 1940. Rural areas joined the grid
about one generation later than cities, reaching a midpoint of the process in 1943
versus 1920 for the townsfolk. This interval measures the clout of rural politi
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120
JESSE H. AUSUBEL AND CESARE MARCHETTI
100%
a,
._
a,
~ 80%
._
c)
111 60%
._
In
4,
o
I
o
40%
20%
a,
AL
Urban
.~
.
/ Farms
1920 1925 1930 1935 1940 1945 1950 1955
Year
FIGURE 7 Percentage of US homes with electne service.
Bureau of the Census (1978a).
DATA SOURCE: US
clans, who secured subsidies for the costly extension of power lines to areas of
low population density, as well as the conservatism of the countryside.
The data further confirm that electricity's first century has encompassed two
eras. During the developmental spread of the system until about 1940, most
electricity went for industry and light, substituting for other energy carriers in
already existing market niches. In the second era, electricity powered new de-
vices, many of which could not have performed without it, such as televisions
and computers. Most of the new demand came in the residential and commercial
sectors.
Average residential consumption has increased by a factor of ten since 1940
and appears in our analyses to saturate in the 1990s at about 10,000 kilowatt
hours per year. One might say that the customer is the home, not the human.
Home appliances have increased by the tens and hundreds of millions: refrigera-
tors, video-cassette recorders, vacuum cleaners, toasters and ovens, clothes wash-
ers and dryers, dishwashers, air conditioners, space heaters, and, more recently,
personal computers, printers, and fax machines.
We emphasize the residential because it is becoming the number-one con-
sumer. Residential consumption has grown faster than other major sectors over
the past decades and in 1993 overtook industrial consumption in the United
States. The number of housing units has grown sevenfold in the United States
since 1900, while the number of people has tripled, as residents per unit have
declined and second homes increased (see Schipper, this volume). As the second
wave of electrification reaches its culmination, the residential share appears des-
tined to plateau at about 35 percent of the total use of electricity, more than twice
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124
JESSE H. AUSUBEL AND CESARE MAR CHERRY
10°
-
~ 1 0-1
-
1o2
10
1 1 1 1
Gas
Turbine (a)
Steam Turbine -
Charles Parsons - ~ GaAs
Triple Expansional Hi/ Diode (b)
Cornish- ~Sodium Mercury
Steam Engines - a/ /
. ~Tungsten PI I am ent
Ames Watt ~
~/~ Cellulose Filament
Thomas Newcomen /
Thomas Savery /. Edison's First Lamp
/ Lam ps
/. Paraffi n Candl e
~..' ~ ~
1700 1750 1800 1850 1900 1950 2000
50%
-
IL
-
10% O
1%
0.1%
FIGURE 9 Improvement in the efficiency of motors and lamps analyzed as a sigmoid
(logistic) growth process. NOTE: Shown in a linear transform that normalizes the ceil-
ing of each process to 100 percent. MAIN DATA SOURCES: for lamps, Encyclopaedia
Britannica (1964~; for motors, Thimng (1958~.
their nightlife, nocturnal energy demand is only one-third of the daytime require-
ment. The ratio of day to night activity does not seem to have changed much. The
ancients actually spent considerable time awake at night, despite miserable illu-
mination. The fine old word "elucubrate" means to work by the light of the
midnight oil, according to the Oxford English Dictionary.
Even if most humans continue to sleep at night, we have pointed out earlier
that their energy-consuming machines can work nocturnally. In fact, remote con-
trol and the shrinking work force required to operate heavy industry ease the
problem. So, too, will linking parts of the globe in sun and shade, summer and
winter.
Still, we should clearly look further for efficiency gains. Much large electri-
cal machinery is already so efficient that little or no gain is to be expected there.
But a discontinuous step could yet come in the progress of machinery. 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, par-
tially offsetting the efficiency gains they offer. The miniaturization of circuits
and other aspects of computing systems in the past two decades shows how
powerfully reducing the size of objects can increase their applications and num-
bers.
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ELEKTR ON: ELECTRICAL SYSTEMS IN RETROSPECT AND PROSPECT
The Splicer
125
In proposing a more general solution we need to introduce another consider-
ation, namely, reliability. The main drawback of an electrical system is that it
permeates the web of social services, so that a breakdown, even for a few hours,
can bring tragedy. A defense against this vulnerability, as well as a means of
addressing cyclical loads, could come with the diffusion of multipurpose mini-
generators at the level of individual consumers. In effect, we would delegate base
load to the global system, leaving peaking and standby to a new multipurpose
household appliance. Multipurpose means the device could produce heat, elec-
tricity, and cold on demand.
Such combined thermal, electric, and cooling systems, which we will call
"splicers," are under development. Attempts so far, such as the FIAT TOTEM,
have been unsuccessful, in part because the marketed models lack the basic
characteristic of zero maintenance required by household gadgets. Still, the
scheme is appealing, both functionally and economically. The Japanese are doing
a sizable amount of research and development in what appears to be a promising
direction: stirring engines with free-floating pistons and a power output of a few
kilowatts. The machines are maintenance-free, silent, and can compress fluids for
the heating and cooling cycles on top of producing electricity with linear oscillat-
ing generators. The models described in the literature are powered by natural gas.
In conjunction with a clean gas distribution system, the penetration of the
splicer as a home appliance over the next fifty years could revolutionize the
organization of the electrical system. The central control could become the switch-
board of millions of tiny generators of perhaps 5 kilowatts. Electric utilities might
initially abhor the technology that brings such functional change, but already
some plan to use it. 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 consum-
ers. A number of well-known machines and appliances need technological reju-
venation, as efficiencies are systematically low. And new machines need to be
invented. At a high level of abstraction, human needs are invariant: food, cloth-
ing, shelter, social rank, mobility, and communication (a form of mobility where
symbols move instead of persons or objects). Let us guess the shape of the new
machines in the areas of vision and warmth.
Efficient Vision
Illumination, the first brilliant success of electricity beyond powering the
workshop, provides a good example. Breaking the rule of the night is an old
magical dream. The traditional tools oil lamps, torches, and candles were
based on a flame with relatively low temperature and small amounts of incandes-
cent soot to emit the light. They performed the task poorly (see Figure 9~.9 The
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JESSE H. A USUBEL AND CESARE MARCHE1TI
typical power of a candle is 100 watts, but the light efficiency is less than 0.1
percent.
Electricity fulfilled the dream, almost from the beginning, with arc lights,
whose emitting source was solid carbon at temperatures of thousands of degrees
centigrade.~° The light was as white as the sun, and efficiency reached about 10
percent. The technical jump was enormous. Theaters, malls, and monuments
were lavishly illuminated. People were seduced by the magic. 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. Symbolically, in 1882
the New York Stock Exchange installed three large "electro-liers," new chande-
liers with sixty-six electric lamps each, above the main trading floor. The exhibi-
tion of the power to break the night came first and dramatically. Penetration of
the technology came later and, as usual, slowly. US cities, as shown earlier,
achieved full illumination only about 1940.
The period from 1940 to 1995 can be called a period of consolidated light.
Lamps became brighter and efficiency rose. To the human eye, the quality of the
light may actually have worsened with the spread of fluorescents. With laser
light, which has terrible visual quality now, we may approach theoretical effi-
ciency, though actual lasers remain inefficient. Will that be the light at the end of
the tunnel?
To return to basics, we illuminate in order to see in the dark. Illumination has
no value if nobody looks. Arriving in a town at night, we always see the roads
brightly lit and empty, so we know of waste. The marvels of the 1980s, electronic
sensors and computer chips, can already scan rooms and streets and switch the
lights off if no one is present. The watt-watch can help, but we can go further.
Sophisticated weapons systems those mounted in helicopters, for ex-
ample feel the thumb of the pilot, observe his eyes, and shoot where he looks. A
camera-computer in a room can watch the eyes of people present and illuminate
only what they watch. Phased arrays, familiar in sonars and radars and developed
now for infrared emitters, are certainly transportable into the visible range and
can create sets of beams that are each directed to a chosen point or following a
calculated track. The apparatus might now look baroque, but with miniaturization
it could be concealed in a disk hanging from the ceiling of a room. Such a gadget
appears to be the supreme fulfillment, illuminating an object only if a human
gazes upon it.
But recall again that the objective is not to illuminate but to see. We illumi-
nate because the eye has a lower limit of light sensitivity and, in any case,
operating near such a limit is unpleasant. The military has developed complicated
gadgets by which scanty photons from a poorly illuminated target are multiplied
electronically to produce an image of sufficient luminosity. The principle is
good; the machine is primitive. If photons flowing in an energized medium (such
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127
as an excited laser crystal) multiplied in a cascade along the way while keeping
frequency and direction, we would have invented nightglasses, the mirror image
of sunglasses. We could throw away all sorts of illuminating devices. A few
milliwatts of power would be enough to brighten the night.
Efficient Warmth
The largest part of energy consumed in the home is used for temperature
control. Space heating accounts for 60 percent or more of total residential energy
use in many developed countries. Heating a home is a notably inelegant process
from a thermodynamic point of view. We use pure free energy (electricity or
fossil fuels) to compensate for a flow of energy from inside to outside having an
efficiency according to the Second Law of Thermodynamics of about 3 percent if
the difference in temperature is 10°C. Heat pumps solve the problem conceptu-
ally, but they see temperatures inside their heat exchangers and consequently
overwork. i2 Moreover, operating on electricity generated upstream, they already
invite inefficiency into the endeavor.
Consider a radically different proposal. Windows are the big leaks, even
when the glazing is sophisticated and expensive. Why not use window panes as
thermoelectric devices, not to carry heat uphill but to stop heat from sledding
downhill, that is, as heat-flux stopping devices?
Thermoelectric generators are usually seen as machines to make electricity
by using the principle of the thermocouple. However, the device is reversible: by
passing electricity through the machine, heat can be moved uphill. Several de-
cades ago refrigerators were proposed using this principle on the basis of its great
simplicity, although efficiencies are low. The old scheme for refrigerators could
be revised in view of new thermoelectric materials and given suitably competi-
tive objectives.
The basic idea is that electrodes on the inner and outer surfaces of the
windowpanes can be made of conductive, transparent glasses. Glass made of zinc
oxide might be sufficiently conductive. Voltages across the glass would be very
low volts or fractions of volts. Holding a temperature differential with zero flux
would be more efficient energetically than putting heat (electrically!) into a house
to balance the outgoing flux.
Electric Motion
So far we have looked at examples where efficiency wins, and net demand
for power grows, only if the human population and its use of devices increase
faster than efficiency. Now let us look at one example where a large new market
might emerge, matching the ultra-high voltage lines and continental connections.
Toward the end of the last century electric motors for vehicle engines at-
tracted much inventive action. Edison and Ferdinand Porsche produced sophisti
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JESSE H. A USUBEL AND CESARE MARCHETTI
cased prototypes. The idea flopped on the roads but succeeded on the rails.
Electric trams clamored through American and European cities, helped create
suburbs, and in some cases connected cities. After 1940 most of the system was
rapidly dismantled, largely because the trams could not match buses and cars in
flexibility or speed. The mean velocity of transport keeps increasing through the
progressive substitution of old technologies with new, faster ones. For France,
the increase in the average speed of all machine transport has been about 3
percent per year during the last two centuries. Urban and suburban railways have
a mean speed of only about 25 kilometers per hour, including stops. Cars have a
mean speed on short distance trips of about 40 kilometers per hour. The latest in
the series are airplanes, with a mean speed of 600 kilometers per hour. Airplanes
will provide most of the increase in mean speed over the next fifty years.
Electric trains succeeded in Europe and Japan for the densely trafficked lines
and still operate today. They have decent acceleration and speed compared with
diesels. But most trains are not fast; the inclusive travel time on intercity rail
journeys is only about 60 kilometers per hour. The fastest trains, the French
trains a grande vitesse (TGVs), are electric. The question for trains is how to
compete with cars on one side and with airplanes on the other. Electricity prob-
ably cannot compete with hydrogen for propulsion of cars and other light ve
hicles.
The great market challenge for the current generation of fast trains, with top
speeds of 400 kilometers per hour, is the short distances of less than 100 kilome-
ters along which cars congest and airplanes cannot compete. The present configu-
ration of airports and airplanes are high-speed but low-flux machines. TGVs
could prove extremely competitive in the intense shuffling of commuters and
shoppers within these distances. A cursory review of Europe reveals about 5,000
kilometers of intercity links fitting the constraints of a 100-kilometer distance and
high potential passenger flux.
Fast trains consume more or less the same amount of primary energy per
seat-kilometer as a turboprop planets or a compact car. From the power point of
view, a running TGV absorbs about 10 kilowatts per seat. The mean power
demand of the proposed 5,000-kilometer system of TGV trains for commuters
and shoppers would be around 6 gigawatts, with a peak of probably 10 gigawatts.
If the concept is successful, this form of transport will be an important consumer
of electricity, but it will take at least fifty years to become fully implemented.
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 re-
quirements: the magnetically levitated (maglev) train operating in a partially
evacuated tube or tunnel. In fact, Swiss engineers have developed the concept of
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129
a vacuum version of maglevs in part to reduce drastically the tunnel boring
expenses, which in Switzerland would account for at least 90 percent of the cost
in a conventional layout (Nieth et al., 1991~. To handle the shock wave from a
high-speed train, a tunnel normally needs a cross section about ten times that of
the train. In addition to narrowing greatly the tunneling requirement, the partial
vacuum greatly reduces friction, making speed cheap and thus expanding the
operational range of the train.
When operated at constant acceleration- for example, 5 meters per second
or 0.5 g (the force of gravity), about what one experiences in a Ferrari sports
car maglevs could link any pair of cities up to 2,000 kilometers apart in fewer
than twenty minutes. Consequently, daily commuting and shopping become fea-
sible. Such daily trips account for 90 percent of all travel and are controlled by the
total human time budget for travel of about one hour per day. With fast, short
trips cities can coalesce in functional clusters of continental size. City pairs
spaced less than 500 kilometers or ten minutes apart by maglevs, such as Bonn-
Berlin, Milan-Rome, Tokyo-Osaka, and New York-Washington, would espe-
cially benefit.
Part of the energy consumption of vacuum maglevs overcomes residual fric-
tion; an economic balance must be struck between the friction losses and the
pumping power to keep the vacuum. Part regenerates the electromagnetic system
that pushes and pulls the trains.~4 The power per passenger could roughly corre-
spond to that of a large car, although these trains may travel at a mean speed of
3,000 kilometers per hour.
The great advantage of the constant acceleration configuration for maglevs is
that the energy required for each length of track is constant and could be stored,
perhaps magnetically, in the track itself. 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 net-
works would see only the need to make up losses. Even assuming 90-percent
efficiency, these would not be negligible. One hundred trains per hour would
demand 1 gigawatt for the single line on which they operated. ~5 The Swiss system
has a final potential of five hundred trains per hour, which would require 5
gigawatts about one-third of current installed Swiss generating capacity.
The first long-distance maglev will probably run in about five to ten years.
Berlin-Hamburg is under construction. The penetration of the technology will be
gradual, as major infrastructural technologies always are. In fact, the next fifty
years will probably be used largely to establish the feasibility, chart the maglev
map, and prepare for the big push in the second half of the twenty-first century. In
the long run, maglevs may establish several thousand kilometers of lines and
become one of the most important users of electricity. A maglev trip per day
becomes a few thousand kilowatt hours per year per person. If India and Eastern
China join life in this superfast lane, the picture of a globally integrated, high-
capacity electrical system begins to cohere.
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JESSE H. A USUBEL AND CESARE MARCHETTI
CONCLUSIONS
The long economic cycles that seem to affect all parts of social and economic
life constitute a good frame of reference for the development of the electrical
system in terms of technology, territorial penetration, birth and death of enter-
prises, and intensity of use. Our examples suggest this is true for the United States
and globally.
Two waves of electrification have passed through our societies. 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.
The fact that the patterns of temporal diffusion and growth are followed
makes it possible to fit dynamic equations to the time series of facts and then
compare them for consistency. This operation indicates that the 1990s are the
season of saturation, which includes the experience of overcapacity or, alter-
nately, underconsumption. Such phases are not uncommon for various branches
of the industrial system, as managers tend to assume that growth characteristics
of boom periods will extend into recessions, while consumers cut corners.
In the short term, total energy and electric energy consumption may continue
to grow at a slower rate than overall economic activity. One interpretation is that
during the expansion period of the long cycles the objective is growth, while
during the recessive period the objective is to compete, shaving costs here and
there and streamlining production. The savings include energy. Meeting goals
pertaining to environmental quality and safety further tighten the system.
A new cycle formally beginning in 1995 started the game again, although the
effects of the restart will not be particularly visible for a few years. Minima are
flat. Looking at the cycles from a distance to grasp the general features, one sees
the periods around their ends as revolutionary, that is, periods of reorganiza-
tion-political, social, industrial, and institutional. We are evidently at this con-
junction, and the electrical system will not escape it.
When the electrical system served the village, a complete vertical integration
was inevitable. Regional coverage, the preferred scale of the past fifty years, also
favored such integration. With the expansion to continental dimensions, a shift in
responsibilities may make the system more efficient, agile, and manageable. The
typical division is production, trunk-line transport, and retailing, with different
organizations taking care of the pieces and the market joining them. The experi-
ments in this sense now running in Great Britain, Australia, and other countries
can be used as a test bed to develop the winning ideas.
Apart from various economic advantages and organizational complications,
the use of splicers on a large scale untried to date may bring an almost abso
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ELEKTR ON: ELECTRICAL SYSTEMS IN RETROSPECT AND PROSPECT
131
lute resiliency, as every subset of the system may become self-sufficient, if
temporarily. The electrical system should also become cleaner, as it intertwines
more closely with natural gas and probably nuclear energy, thus furthering
decarbonization. A sequence of technical barriers will appear, and thus the pro-
cess of systematic research and innovation will continue to be needed; it will
produce timely results.
In fact, our analyses suggest that rates of growth of technology tend to be
self-consistent more than bound to population dynamics. Population, however,
defines the size of the niche in the final instance. Thus a key question is, how long
will it take to diffuse Western electric gadgetry to the 90 percent of the world that
is not already imbued with it? The gadgetry keeps increasing. Followers keep
following, if more closely. Based on historical experience, diffusion to distant
corners requires fifty to one hundred years. Even within America or Europe, as
we have seen, pervasive diffusion takes that long for major technologies. So most
people may have to wait for most of the next century to experience nightglasses,
splicers, and maglevs. These devices may be largely features of a fourth wave of
electrification, while the spread of the profusion of information-handling devices
dominates the third wave that is now beginning.
Considered over centuries and millennia, the electrical adventure is deeper
than a quest for gadgets. In 1794 Volta demonstrated that the electric force
observed by Luigi Galvani in twitching frog legs was not connected with living
creatures, but could be obtained whenever two different metals are placed in a
conducting fluid. Today we use electricity to dissolve the difference between
inanimate and living objects and to control and inspire the inanimate with more
delicacy than Dr. Frankenstein. 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. This ancient aspiration for action at a distance and
direct command over the inanimate will drive invention, innovation, and diffu-
sion for hundreds of years more; we come full circle to the electron of the ancient
Hebrews and Greeks.
ACKNOWLEDGMENTS
We thank Perrin Meyer, for research assistance and figure preparation, as
well as Arnulf Grubler, John Helm, Eduard Loeser, Neboj~a Nakicenovic, and
Chauncey Starr.
NOTES
1. "Oh subtle fire, soul of the world, / beneficent electricity / You fill the air, the earth, the sea,
/ The sky and its immensity." Quoted in Darnton (1968, p. 29).
2. For general histories of electrification, see Hirsch (1989), Hughes (1983), Nye (1990),
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32
JESSE H. A USUBEL AND CESARE MAR CHEITI
Schivelbusch (1988), and Shurr et al. (1990). For data and information on the early history of energy
and electricity, see Schilling and Hildebrandt (1977).
3. Such diffusive processes are well fit by the logistic equation, which represents simply and
effectively the path of a population growing to a limit that is some function of the population itself.
For discussion of applications of logistics, see Nakicenovid and Grubler (1991). On the basic
model, see Kingsland (1982).
4. A kilowatt (kW) is 1,000 watts; a megawatt (MOO) is 1,000,000 W; a gigawatt (GW) is 1,000
MW; a terawatt (TOO) is 1,000 GW. US generating capacity was 735 GW in 1990.
5. Power is equal to V2/R, where V is voltage and R is resistance.
6. For an analysis of electricity projections, see Nelson et al. (1989).
7. Sulfur and other emissions from power plants also cause ills, but these have proven to be
largely tractable (see Nakicenovic, this volume).
8. While Carnot efficiency (now about 60 percent) limits heat cycles, fuel cells do not face such
a limitation, as they are not based on heat cycles.
9. Gaslight, with a mantle with rare-earth elements, was a superior source of bright light for a
period.
10. The plasma struck between the two carbon electrodes also emits.
11. Sticking to monochromatic light, a ray proceeding in a resonantly excited medium stimulates
emission and becomes amplified. Amplification is relatively small with present devices; hence the
ray must travel up and down between mirrors. But no physical law limits amplification to such low
levels. Semiconductor lasers, pumped by electric voltage, might hold the solution. In a second
stage, they should also operate for a number of colors.
12. The equivalent free energy of treat flowing out of a building is measured through the tempera-
tures inside (T1) and outside (T2) in kelvin and is (T1-T2)/Tl. In the case of a heat pump, due to
temperature drops in the heat exchanger, it pumps heat from a temperature lower than T2 into a
temperature higher than T1.
13. For example, airplanes of the type ATR-42 or Dash.
14. We can calculate the amount of energy circulating in the system for a maglev with constant
acceleration operating over a distance of 500 kilometers. 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 corre-
sponds to 5 x 101 l joules, or approximately 140,000 kilowatt hours. A mean loss of 10 percent
would require 14,000 kWh for one thousand seats, or 14 kWh per seat over 500 km. This would
correspond to 84 kW per passenger at a typical trip time of 10 minutes (e.g., Bonn to Berlin).
15. For example, fifty trains might operate in each direction, spaced one minute apart. They can
start from different stations or lanes. One per minute would be the frequency in the neck of the
tunnel.
1996).
16. For discussions of models of organizational change in the electricity industry, see Sack (1995,
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Representative terms from entire chapter:
kilowatt hours
