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OCR for page 88
4
Examples of Electrification and
Productivity Gains
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Gross National _ :1 Electricity
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DEMAND
In the preceding chapter the past relationships between electricity and
productivity growth were examined econometrically to understand better
the ways technical change and electr ic ity use at feet our economy. In
this chapter we give some examples of gains in the efficiency of
production through particular technical change, that is, through
electr i f ication. The d iscussion bears on the shaded portions of the
above reproduction of Figure 1-1. Although considering individual
examples about specif ic users and processes may be illuminating, their
aggregate effect is hard to predict. Even so, some general
88
OCR for page 89
89
observations about past industrial technological advances, and the role
of electricity in them, suggest that electricity is an important energy
form in making technological progress. ;
The examples illustrate the general point that advanced electro-
technolog ies applied to a particular process of ten save electricity and
other inputs per unit of output. Less quantif table, but equally
important, is the fact that resulting lower costs and higher quality
can expand the market, thus increasing total electricity input.
Furthermore, in the next 10 to 20 years current processes will
incorporate new variations in technique and new products, the
competitiveness of which may depend on the new production techniques.
The flexibility of electricity will support such innovative processes.
Finally, the examples will call to mind other applications, such as the
reduction of aluminum ore, that are essentially impractical by
nonelectrical means.
The material in this chapter bears on two of the principal
conclusions of the study:
Technical change has made possible many new opportunities for
exploiting the special qualities of electricity. In the past
these changes were often associated with increased intensity of
electricity use, but in the future their net effect on that
intensity will depend on the balance between their increased
penetration and the increased efficiency of these applications.
O There is further potential for increasing the efficiency of
electricity use, particularly in the residential and commercial
sectors.
ELECTRICITY AND TECHNOLOGICAL PROGRESS
The attractiveness of electricity as an energy form, as it is
assoc iated with advances in production technology and with information
and control technology that may not be directly involved in production,
arises from two of its significant characteristics. The most important
is that electrical energy is ~ highly ordered form of energy: in the
language of physics, its entropy is low. Thus, electricity is
applicable quite efficiently to a wide variety of conversion
processes. The other attractive characteristic of electricity is that
its final form is relatively "clean." In particular, throughout the
world electrical energy is distributed at one of two common frequencies
and at a few easily changed voltages. Electrical equipment can
therefore be reliably and cheaply engineered with the confidence that
expensive adaptations will not be necessary to accommodate supply
pecularities or waste products at the point of use.
The most obvious use of electricity in many industries is in
heating. The advantages of electrical over fossil fuel heating extend
beyond environmental concerns. The main benefit is the flexibility
OCR for page 90
so
with which el ectrical energy can be delivered, controlled, and tailored
to optimal locations in space, to temperatures or energy levels for
desired processing chemistry, and to the limitations of the materials
used in that processing. Generally, such applications represent a
substitution of electrical energy for other energy forms, sometimes
with an increase in the efficiency of total energy use.
Any generalization about the implications of advanced technologies
for increased electricity use is somewhat uncertain. This uncertainty
arises because many of the newer processes carried out by advanced
technologies require less electrical energy than the processes they
displace. Concentrating heat at the deposition site--using induction
heating, microwave heating, or electron beam welding, for example--is
one general case of using the special properties of electricity to
drive novel process technologies. In the sense of electrical energy
required per unit of output, many of these technologies are less
electricity-intensive than, for example, resistance heating or arc
welding. In short, there are clear examples of enhancing productive
efficiency while using less electrical energy. Still, the enhanced
efficiency may improve competitiveness and market penetration so that
total consumption increases.
Again, although the efficiency of individual electricity-using
technologies can be analyzed, predicting the mix of technologies to be
expected in the future will at best be incomplete and at worst, wrong.
While one can anticipate the decline of some currently employed
technical processes, forecasting their future replacements is quite
uncertain. Even so, it is instructive to consider some of the diverse
forms of electrification that may accompany technical change.
KINDS OF TECHNICAL CHANGE TAT ALTER ELECTRICITY USE
Technical changes that alter electricity use may be classif fed by how
they displace energy to achieve economic gain. The categories selected
here represent typical applicat ions of electric ity in cur rent use. It
is hard to make an exhaustive survey of such processes. Thus, we focus
on a few broad, qualitatively different classes:
o Technical changes in which processes using electricity as the
primary energy form displace traditional processes that depend on
fossil fuel heat, mechanical energy distribution systems, or human
labor. Generally such processes are the earliest advantageous
industrial applications of electricity, and the resulting rise in
productivity is generally accompanied by a rise in the use of
electrical energy. Choice of these processes may be encouraged by
increasingly attractive prices of electricity relative to those of oil
and gas.
o Technical changes in which advanced electrotechnolog ies d isplace
older electrotechnologies and provide more eff icient matching of energy
availability to need, resulting in a decrease in energy consumption per
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91
unit of output and often a rise in productivity with respect to other
inputs as well. These new technologies may have many of the following
attributes: high energy efficiencies; less product waste; better
precision and control in the attainment of technical objectives;
reduction of the time necessary to attain process objectives; less
severe environmental impacts; reduced labor and maintenance
requirements; better reliability and quality assurance; and overall
economic advantages.
0 Technical changes in which additional capital investment in
equipment and structures displaces some operating energy requirements.
Many conservation techniques represent this kind of substitution,
motivated by changing prices and the availability of new conservation
technolog ies and of information about such applications.
o Technical changes in which the enhanced productivity and quality
of output that depend on electricity are qualitatively clear, but are
not yet easily classified by the direction of energy displacement.
Many such applications, including computers, la sers, pla smas, and
electrophoresis, are impractical or unachievable by nonelectr ical
means.
Of course, these general classes describe only roughly any given
application. In particular, numerous modern applications for saving
energy in heating and cooling buildings depend not only on the
availability of the advanced technology, but also on the commitment of
a larger initial investment than if the technology were not adopted.
In such cases, productivity growth depends both on technical change and
on capital substitution. All these categories of technical change tend
toward higher productivity in the general economy through increases in
productive efficiency in individual f irms. The second and third
classes of change described above can be expected to show decreased
electricity use per unit of output.
The four categor ies above by no means embrace the wide range of
electrical applications, nor are they necessarily the most important
for systematic evaluation. They do, however, provide insights into the
ways technical changes in using electricity may increase productivity
and change energy consumption. An example of each category is g iven
below.
EXAMPLES OF ELECTRICITY-DEPENDENT TECHNICAL CHANGE
Arc Furnace Steelmaking
Arc furnace steelmaking is an example of the substitution of electrical
energy for more traditional energy forms, where extensive changes also
occur in other aspects of production. These changes encompass not only
the energy form used, but also the selection of raw feed materials, the
ways specific production can be tailored to the needs of individual
users, and, perhaps most importantly, the decentralization of plant
locations.
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92
The production of molten steel f rom scrap in an electric arc furnace
is the primary competitor to the conventional blast furnace-basic
oxygen f urnace (BF-BOF) steelmaking process (Burwel~ and Devine,
1984~. Figure 4-1 illustrates these two processes. In conventional
steelmaking, iron ore must be pelletized and introduced into a blast
furnace with limestone and coke to produce molten iron. The iron is
further processed in a basic oxygen furnace with pure oxygen and other
chemical additives to produce steel. Open hearth furnaces,
traditionally used to produce steel until the 1950s, have by now been
almost completely displaced by the BOF in the United States. In the
electric furnace, steel scrap is melted directly with a high-intensity
arc. The desired steel composition is controlled primarily by
ad justing the composition of the scrap charge, though some ret ining
also takes place in the furnace. Although virtually all of this steel
produced in the United States today is made from scrap, electric
furnaces can also melt direct-reduced iron generated from ore. This
process may become significant over the next decade as scrap supplies
are depleted.
Scrap can be used only in limited quantities as an added constituent
in BF-BOF steelmak~ng; combustion heat sources are not intense enough
to permit melting scrap economically. As pointed out earlier, however,
extremely high temperatures are attainable with electric arc heating;
and it is this characteristic that has made electric furnace
steelmaking relatively economical. Table 4-1 compares typical
production costs for the two processes. Although scrap is more
expensive than the feedstocks for the BF-BOF process, other costs,
notably of energy and capital, are signif icantly lower for the electric
arc furnace. Table 4-2 compares the primary energy requirements for
the two steelmaking processes. The electric furnace process requires
about one-third the primary energy ~ fuel to the power plant) as the
BF-BOF process.
Capital costs of BF mills are typically about $4 50 per annual ton of
capacity, compared with about $100 per annual ton of capacity for an
electric furnace mill. Furthermore, integrated mills must be sized to
take advantage of optimal economy of scale because of the requirements
for large ore-handling, coke-making, and pollution abatement
f acilities. In the United States, the average plant capacity of BF
mills is somewhat over 3 million tons per year and that of electric
furnace mills is under 0.5 million tons per year. The economic
viability of small electric "mini~nills" close to particular markets has
introduced decentralization to the steel industry. Integrated mills
are located in only 15 states, with 75 percent of their capacity
concentrated in the eastern Ohio-western Pennsylvania and the Chicago
areas e Electric mills are located in 32 states, with no more than
about 25 percent of their capacity concentrated in any one narrow
geographical region.
The relative profitability of arc furnace steelmaking is now
accepted as axiomatic in the industry. The fact has been demonstrated
especially during times of economic decline. In such times electric
mills have generally fared much better than BF-BOF mills, partly
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93
3
b
4
lion Ore
Pellets
AL 1~
. ~
Si nter
ffl~
_t'~ .~
Limestone ~
~ Crushed
Coal
At&
Blast ~
1d ,11
. Low
Slag LO
..~.,
Coke Ovens
c' ~
Lime and Flux
0 1 i r 1 ~'. otter Steet
_
By_
I_ '.'otte~ Steed
_xu
Open Hearth Furnace
Basic Oxygen Furnace
~ _ ~
OF Reduction ~
iron Ore my
~~
i\7
~Scrap
[_~
_ r __
~Eiec~rlc Furnace
'` o't~' Steel,
FIGURE 4-1 Comparison of steelmaking processes: (a) integrated blast
furnace, (b) electric furnace.
SOURCE: Schmidt ( 1984)
.
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94
TABLE 4-1 Comparative Costs for Producing Molten Steel (1982 Dollars
per Ton)
Blast Furnace-Basic Scrap-Electric
Cost Element Oxygen Furnace Furnace
Raw mater ial
Energy (coke @ $150/ton,
electricity @ $0. 045/kWh)
Interest on capital
Labor
92.40
63.80
33.00
8.80
Maintenance and overhead 22.00
117.25
21.00
12.25
7.00
17.50
Total 220.00 175. 00
SOURCE: Adapted from Schmidt (1984~.
TABLE 4-2 Pr imary Energy Requirements for Molten Steel
Process
Blast furnace-basic oxygen furnace
Coke ovens and blast furnace
Basic oxygen furnace steelmaking
Scrap-electric furnace
Pr imary Energy
(106 Btu/net ton)
21.1
19.5
1.6
7.4
SOURCE: Adapted f ram Schmidt (1984)
.
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because the price of scrap is likely to be low and partly because of
the inherent operational flexibility of electric furnaces. The
flexibility in output batch size, feedstock, and product specifications
yields better deliverability, and therefore better coupling to market
needs,-resulting in better market penetration. The ability of
minimills to produce customized output on relatively short schedules
provides a market advantage in many applications that overcomes lower
unit costs of offshore steel. Integrating customized production with
computer-assisted design and computer-assisted manufacturing in the
future should further increase the competitiveness of such producers
relative to that of the producers of bulk steel. These observations
have led to projecting significant growth in electric steelmaking
during the rest of the century, even though only modest growth in
overall steelmaking capacity is anticipated. In 1978, U. S. electric
furnaces produced 33 million tons of steel, about one-fourth the
total . The American Iron and Steel Institute has predicted that the
U.S. figure could exceed 50 million tons in 1988, about one-third the
total. A U.S. capacity of about 70 million tons has been projected for
the year 2000. These figures should be interpreted cautiously: they
are based on hypothetical scenarios of overall demand and use of
production capacity. The figures are noted here simply to indicate the
clear relative economy of the electric furnace process.
Metals Processing by Lasers and Electron Beams
Processing metals with lasers and electron beams exemplifies the
displacement of older electrotechnologies by more advanced ones. Some
of these new techniques constitute extraordinary advances in performing
basic cutting and welding operations in metals. Before,
electrification in the form of power drives for saws and electric arc
welding was the standard technology. Introducing the advanced
technologies significantly enhances productivity and reduces electrical
energy use per unit of product. Laser and electron beam processing
both have broad applications, including cutting, welding, drilling, and
heat treating. They also affect industries ranging from aircraft and
automobi les to home appliances and electronics.
Many kinds of metal fabrication are labor-intensive, so processing
speed and number of operations are critical to overall production
economy. Although it has been shown, in fact, that laser and electron
beam processes of ten conserve energy compared with conventional metal
cutting and welding processes, this discussion focuses primarily on
labor-related parameters.
Laser Processing
The high energy deposition rates of lasers and their ability to control
the energy source precisely in location, direction, time, and intensity
together give rise to the productivity advantages illustrated here.
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96
For example, circular saw blade blanks can be laser cut to customized
specif ications, providing shorter delivery times and better quality
than convent tonal stamping processes .
Table 4-3 compares typical laser cutting speeds with those of
conventional mechanical saws for steel and titanium plates of varying
thicknesses. Titanium presents a particularly difficult sawing
operas ion because of its high hardness . Hardness i s essent tally
irrelevant- in laser cutting, since the laser beam simply vaporizes the
metal. As a result, cutting speeds with the laser are roughly 25 times
faster than with sawing . For working steel, which is not as hard as
titanium, a speed advantage of 5 to 10 times is still achievable.
Table 4-4 shows the resulting labor savings for a typical
application--cutting complex titanium shapes in manufacturing high-
performance aircraft. These figures include setup and postprocessing
time as well as actual cutting time. Employee-hour savings of 60 to 6 5
percent are typical with the laser process. Overall cutting costs for
this application are shown in Table 4-5. Cost savings for the laser
process range from about $1 to $3 per foot, depending on material
thickness. The capital cost of the laser system, however, is
significantly higher. This cost premium would typically be recovered
in producing about 2, 000 parts of 1/2-in. thickness and of 20-ft
perimeter (structural elements, for example) or about 5, 000 or 6, 000
parts of 1/8-in. thickness when the perimeter is similar (for example,
fuselage skin panels).
Electron Beam Process ing
The primary application of electron beams today is in welding thick
steel and aluminum sections, for example, in the automotive and
shipbuilding industries. Electron beams with velocities approaching
the speed of light have tremendous penetrating power and can be
magnetically focused to an area about 1 mm2. Plates rang ing f rom 1/2
to 6 in. in thickness can be welded in a single pass with an electron
beam while conventional arc or oxyacetylene welding techniques require
2 to 20 passes. The intensity and focusability of electron beam
welders provide indirect as well as direct processing speed
advantages. Figure 4-2a illustrates that the heat-affected zone in
conventional multipass weld varies from almost zero at the bottom of
the weld to approximately the plate thickness at the top. By
comparison, the electron beam weld is almost uniform in width
throughout the plate and results in a relatively small heat-affected
zone (typically the thickness of a pencil). This feature results in
high weld integrity and low transverse shrinkage; uneven shrinkage in
conventional welding distorts the plate as shown in Figure 4-2b,
requiring postprocessing heat treatments to correct that distortion.
Residual stress remains as a failure-promoting attribute even after
stress relief of conventional welds.
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TABLE 4-3 The Comparative Cutting Speeds of Lasers and Saws
Average Cutting Speed (in./min)
for Different Thicknesses
Material Process 1/50 in. 1/16 in. 1/8 in.
Titanium Saw 8.5 5.8 4.4
Laser 200 160 120
Steel Saw 8.5 5.8 4.-4
Laser 80 40 20
SOURCE: Schmidt (1984)
.
TABLE 4-4 Comparative Labor Costs for Cutting Titanium Aircraft
Components (Including Setup and Postprocessing Time), with Band Sawing
and Laser Cutting Techniques
Band Sawing Laser Cutting Savings
Component Type (man-min/ft) (man-min/ft) (percent)
Large contoured skin panels 10.4 3.65 65
Ribs and longerons 6.0 2.32 61
Small skin panels 6.25 2.38 62
SOURCE: Adapted from Schmidt (1984)
.
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Cutting Process
Capital- Investment
~ dollar s ~
98
TABLE 4-5 Titanium Cutting Cost Comparisons ~ in 1982 Dollars)
Total Cost (dollars/ft)-
Mater ial Thickness
1/8 in. 1/4 in.
1/2 in
.
Saw
Laser
2,000
96, 000
1.52 2.18 4.15
0.71 1.19 1.28
aIncludes operating and secondary f inishing costs
SOURCE: Adapted f rom Schmidt ( 19 8 4 ) .
.
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99
a
CONVENTIONAL WE LDI NG
Molten mesai
~ ..
'~/~/~/~
b
E LECTRON B EAM WE LDI NG
High-speed stream _ I ~ Molten metal
c,! electrons ~ ,:
~/~///,~/~//~
Fusion zone (heat-affected area)
1
WELDS SUPERIMPOSED
Conventional weld zone
..
Electron beam weld zone
Angular distortion caused
by uneven shrinkage at top
and bottom surfaces
Parallel sides of Reid zone
produce uniform linear shrink;aae,
causing no angular distortion
FIGURE 4-2 (a) Comparison of hea~-affected zones for conventional and
electron beam welding, (b) distortion of parts from shrinkage. The
lower residual stresses in the parallel weld minimize regions
susceptible to cracking and failure.
Source: Schmidt ( 19 ~ 4 ~ .
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Table 4-6 shows the overall speed and cost advantages of electron
beam welding over conventional inert-gas arc welding. Although energy
use is not the primary factor in welding production costs, the electron
beam process is extremely energy-efficient, typically requiring less
than one-tenth the energy of arc welding. More significantly, complete
welding time, including setup and postprocessing, is typically reduced
by the electron beam processing by about five times. The resulting
cost differentials per inch of weld range from 400 to 450 percent. As
in using lasers, however, the initial investment in electron beam
equipment is high; thus the process is best suited to high-production
applications, such as welding automobile bodies and chassis components.
Investments in Energy Efficiency of Buildings
Capital investment in a wide variety of passive or active energy
conservation systems can reduce the energy requirements necessary for
acceptable environments in commercial buildings and residences. Many
of these measures are equally relevant to electric and nonelectric
means of space conditioning. However, to the extent that such
investments affect electricity use for heating, ventilation, air
conditioning, and lighting, they exemplify the third category of
technical change described above. The following approaches are among
those already well known and practiced:
o Using insulation, double glazing, and tinted and reflected
glazings
o Using heat pumps and other more efficient heating, ventilation,
and air-conditioning equipment
o Using advanced lighting technologies
o Using energy storage systems to reduce peak demand
o Improving controls for more efficient energy management
o Improving building design.
Some of these features can be retrofitted, but with less effect on
energy use. Applying these techniques in new construction, however,
can provide dramatic annual reductions in total energy requirements.
The potential of implementing such measures is captured in Figure
4-3, which presents past trends and future possibilities in the energy
intensities of office buildings. Energy use in typical new commercial
buildings is estimated to have risen from about 300 thousand British
thermal units per square foot per year (kBtu/ft~-year) in 1952 to
about 480 kBtu/ft2-year in 1975. The U.S. office building stock in
1960 is estimated to have used about 350 kBtu/ft2-year. Evolving
standards suggest that lower office building resource energy
intensities are attainable in new construction, for example, about 10
kBtu/ft2-year in the early 1980s. A still lower value of about 70
kBtu/ft2-year for new construction is seen for 1990, presuming such
operations are economical. Average of f ice building resource energy
intensity for the existing stock will Gradually fall as ~ result of
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TABLE 4-6 Comparison of Electron Beam (EB) and Metal Inert Gas
(MIG) Welding
Maraging Steel
( 1-in. Thickness)
Titanium
~ l-in. Thickness)
Feature EB MIG EBMIG
Number of passes 1 10 110
Welding speed 40 10 IS20
~ in. /min/pass)
Total welding time 0.3 12 0.86
(min/ft)
Total setup, weld, 49 280 55243
and clean time,
typical job (min)
Re let ive C05t
(operating and labor)
1.0 4.1
1.0 4.5
SOURCE: Schmidt (1983~.
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102
500
400
300
-
En:
LL
a
LL
LL
~200
o
u'
LL
100
o
U.S. office building:
/ `\ Trend of various
I U.S. office building stock standards:
ASHRAE 9~75
/ vo luntary standard
0\'
_ \, ASHRAE 90-75R
Swedish office building stock ~ /
/ ~'~ ~BEPS
Swedish office buildings\\~4 farsta ~ ~
\ ~ Folksam an
Embargo \
.Swedish SBN-75
1 1 1 1 ' ~ 1 1 1 1 1
1952 1960 1 970 1980 1990
YEAR B U I LT
FIGURE 4-3 ()f' ice building resource energy intensity,
40-year trends.
NOTE: Trends in annual energy use per unit floor area per year of new
U. S. . and Swedish off ice buildings. Seven recent energy-ef f icient
office buildings are represented by "*". ASHBAE, American Society for
Heating, Refrigerating, and Air-Conditioning Engineers; BEPS, Building
Energy Performance Standards; LCC, life cycle cost. Electricity is
counted in resource energy units at 11, 500 Btu per Koch.
SOURCE: Adapted f rom Kelly and Gawell (1981)
.
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improved standards for new construction, but the average will lag the
standard because of the slow pace of stock turnover and retrofit.
Efficient lighting and energy storage are of particular interest for
energy conservation in buildings. Lighting in commercial buildings
contributes a significant f raction of the air-conditioning load and
also contributes to a reduction in heating load during cold weather.
Potent ial improvements are atta inable in at least two ways . Improved
more daylighting will cut lighting heat loads
1.5 watts per square foot (W/ft2) to the
., _ _ With new technologies for highly eff icient
lighting, the typical f luorescent lamp ~ 80 lumens/W) may lead to to
more advanced types of lighting:
designs that allow for
f rom a typical value of
lower value cuff 1 W/ft2,
o Isotopically enhanced lamps (110 lumens/W) by 1985
o Magnetically loaded lamps ~ 135 lumens/W), by 1990
0 Two-photon phosphor lamps (200 lumens/W), by 1995.
The technology and applications of energy storage for cooling have
gained significant popularity. Their main contribution is through
reducing peak loads. In addition, since cooling storage takes place at
night at relatively lower ambient temperatures, energy can be saved
because of the resulting higher efficiencies of the heating,
ventilating, and air-conditioning system. Typical storage media
include chilled water and ice. Phase-change polyalcohols are being
researched and may be used. All these methods require separate storage
facilities, which pose a special challenge in retrofitting buildings.
In new buildings, the thermodeck hollow-core floor slab integrates
heating and cooling storage into the structure of the building. This
design requires no visible structure for storage. Many such
applications are only marginally productive, and their effectiveness
must be determined by analysis of the specific situation. However,
penetration of storage-augmented systems is increasing.
Automation
Automation is an example of technical change involving electricity
where the promise of enhanced productivity is already clear but the
impact on ultimate energy use is not. Such applications of electricity
have a direct bearing on efficiently using time, space, capital, labor,
energy, and materials, particularly in the commerc ial and industr ial
sectors. However, corresponding biases of productivity growth, as
discussed in Chapter 3, are not yet established. We have not yet
measured whether automation is capital using, electricity using, labor
saving, materials saving, or anything else.
Computer-aided technical analyses, communications systems,
miniaturization of office equipment, and electronic storage of data are
some applications now receiving wide attention. Nevertheless, the full
range of applications cannot be foreseen at this time. In addition to
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end-use applications, growth in the use of automation equipment will
positively affect the economy by encouraging the growth and development
of new industries.
In manufacturing, terminal equipment is used for data entry and data
access. Mainframe computers manage data bases and electronic messages
and perform scientific and engineering calculations. The more
effective handling of information is essential to optimizing overall
productivity of a firm or an economic sector. Automated information
systems can effectively match and synchronize the flow of materials,
equipment, designs, labor market, and delivery data, for example.
In retail trade, the primary application is point-of-sale terminals
tied to minicomputers. This use not only simplifies individual
transactions but also introduces real-time inventory control, thereby
reducing invested capital.
In education, electronic tools are also becoming widespread.
Elementary and secondary schools increasingly are making microcomputers
available to students, together with courses in their use. Colleges
and universities are integrating computers into their curricula.
Although this discussion focuses on automation in the commercial and
industrial sectors, there will probably be significant use of
microcomputers and videotext equipment in individual residences also.
Few data are available to estimate the potential relationship
between office automation and electricity use. The Electric Power
Research Institute (EPRI) has attempted to quantify this relationship
(Roach, 1985~. Table 4-7 lists various types of electronic equipment
and their typical power requirements. These values have been used in
the preliminary estimate of electricity use discussed below.
Roach assumed that 3.5 million terminals and 13,000 mainframe
computers would be installed in off ices in the manufactur ing sector.
Point-of-sale terminals would be installed at all stores with f ive or
more employees, store growth would be 34 percent by the early l990s,
and 43 percent of the terminals would replace electronic cash registers
in the retail sector. Each college student and one in five elementary
and high school students would have microcomputers. All homes with
incomes of greater than $25,000 would install a microcomputer.
The capacity required, based on these assumptions, is about 30,000
MW. The electric energy requirement, similarly, is about 100, 000, 000
h per year. Such calculations are of course preliminary. In
addition, how much other energy-using technology may be displaced is
not well understood. EPRI is continuing the study of electricity use
and will extend it to include the many nonmanufacturing offices, health
care facilities, and financial institutions.
However, the impact of using such equipment on productivity and
eff iciency is not really measured by the electricity consumption of
office machines and computers. Rather, the proper measure is the
improved handling of information to make the most efficient and
coordinated use of production facilities, labor, and materials. To
take a single example, the inventory control for replacement parts for
computers is itself a large, though largely invisible, industry.
Without this k, nd of system, the worldwide penetration of U.S.-made
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TABLE 4-7 Estimated Power Requirements for Electronic Office Equipment
Technology Brand Features
power
Requirement
(watts)
Microcomputer IBM PC 512-kilobyte memory, two disk340
drives, monochrome screen,
dot-matrix printer
Microcomputer IBM PC/XT 512-kilobyte memory, 10-mega- 614
byte hard disk drive, color
screen, dot-matrix printer
Microcomputer Apple 128-kilobyte memory, one disk 60
Macintosh drive, screen
Microcomputer AT&T System unit only 230
Minicomputer IBM System Up to 8 million characters of 8,500
38/Model memory, IBM 3370 for storage,
8 IBM 3262 for printing, tape
drive, and five terminals
Minicomputer DEC VAX DEC RA81 for storage, LP06 7,310
11/750 for printing, and five
LA120 terminals
Minicomputer
DEC VAX
11/780
Mainframe IBM 3084
Up to 4 megawords of memory,9,110
DEC RA81 for storage, LP06
for printing, and five
LA120 terminals
Up to 96 million characters22,800
of memory, IBM 4248 printer,31,300
IBM 3380 for disk storage
Computer IBM 3279 With mainframe 300
terminal
Computer IBM With system 38 200
terminal
POS terminal! IBM 365 320
POS terminal NCR 280 400
POS terminal IBM 3684 360
Large video RCA PJR 50-in. screen 235
screen
Video cassette RCA 300
recorder
Microfiche Minolta 250
reader and RP401e
printer
Phone recorder Panasonic
20
TYPOS: Point-of-sale.
SOURCE: Roach (1985).
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computers would be impractical, since the parts availability and
replacement channels would become much more costly and much less
responsive to need.
A ful 1 discussion of automation in the industrial sector is not
necessary for the purposes of this section. However, the technology
should at least be cited as a primary tool for higher process
efficiency, higher quality, and the conduct of operations not practical
by manual means. Essentially all advances in automation depend on
electrical sensors, actuators, and computerized control systems. There
are already products, such as automobile bodies, for which the market
share of nonautomated production is rapidy declining. For these
products, automation is perceived as the most practical route to
consistently high quality and thus competitiveness.
OTHER INDUSTRIAL TECHNOLOGIES
Many other examples of electricity-dependent change, particularly in
the industrial sector, are pertinent. They range from plasma processes
for metals reduction, melting, and chemical processing through
electroytic processes for separating and refining metals and chemicals
to infrared and ultraviolet radiation curing. More complete lists of
industrial opportunities are given in Table 4-8 and Table D-1 of
Appendix D. Examples drawn from commercial, residential, and
transportation sectors are given in Tables D-2, D-3, and D-4,
respectively, of Appendix D.
THE S IGNIF ICANCE OF ELECTRIF ICAT ION
As noted at the beginning of this chapter, its purpose has been to
describe some of the technologies that will shape the future
relationship between electrification and gains in production
efficiency. More specifically, various new electrotechnologies promise
to increase national productivity through new applications of
electricity. Chapter 3 showed that the relationship of electricity to
sectoral production is dual: (1) for many industries technical change
is electricity using in the sense that it increases the share, relative
to those of other inputs to production, that a given change in
electricity input value contributes to change in output-value and (2)
for the same industries a drop in the price of electricity, in
association with technical change, increases their productivity
growth.
The examples here allow us to conclude that electricity has unique
properties that make it an attractive form of energy, namely:
~ Constituting a highly organized form of energy, virtually
completely convertible into other forms, such as motion, heat, light,
or chemical potential
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TABLE 4-8 Industrial Electrotechnologies and Their Applications
Technology
Major Applications
Arc furnace steelmaking
Plasma-based metals reduction
Plasma-arc production of
chem icals
Bigh-temperature electrolytic
reduction
Induction melting
Plasma melting, cutting,
and spraying
Induction heating
Electroslag remelting and
casting
Laser materials processing
Electron beam heating
Other high-temperature
technologies (resistance
melting, resistance heating,
vacuum melting, homopolar
pulsed heating, etc. )
Beat pumps and mechanical
vapor recompression
Electrolytic separation
and electrochemical
synthesis
Dielectric heating with
mic rowaves and high-
f requency red fat ion
Ultraviolet and electron
beam radiation curing
Othe r med ium- and low
temperature technologies
Wide range of steelmaking processes
Extractive metallurgy and ferrous
metals processing
Production of acetylene and ethylene,
use of coal to produce teas lo
chemicals, etc.
Improving productivity in producing
aluminum and magnesium
Improving productivity in many
varied applications in metals
production
Large-scale melting of basic metals
Forg ing industry and potent ial
large-scale applications
Production of high-alloy ingots of
simple geometry and potentially those
of complex geometry
Metal cutting, drilling, welding, and
heat treating
Welding and heat treating in
automotive, shipbuilding, and
related industries
Materials production and fabrication
Bigh-temperature heat recovery
(e.g., in pulp and paper
industries), distillation, and drying
Production of inorganic chemicals,
water treatment, trace metal removal,
etc.
Food processing and drying
applications
Improving productivity in the
coatings industries
Surface coatings, various industrial
operations, uranium. separation, etc.
SOURCE: Adapted from Schmidt (1984).
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fuels
o Permitting previously unattainable precision, control, and speed
o Providing temperatures greater than those available using fossil
0 Flexibly operating process equipment on power generated f ram
many fuels
o Leading to few, if any, waste products and environmental hazards
at its point of use, compared with fossil fuels
0 Requ ir ing no inventory .
These properties of electricity underscore its importance as an energy
source in high-technology, information-based activities.
Electrification is also an industrial process that can change not
only the form of energy used but also the amount and kind of labor,
capital, and materials inputs; product quality; and the location of
manufacture. These changes may result in increased efficiency of
production, in the form of equivalent output at lower input cost, and
hence, lower prices.
The foregoing examples illustrate the strong relationship between
technological improvements, the use of electricity, and increases in
the eff iciency of production. The question remains whether this
relationship will continue, and what its net effect will be on
electricity consumption. This is the subject of Chapter 5.
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REFERENCES
Burwell, C. C., and W. D. Devine, Jr. 1984. Industrial
Electrification: Early Beginnings and Current Trends. Technical
Report. Oak Ridge, Tenn.: Institute for Energy Analysis, Oak Ridge
Associated Universities.
Kelly, H., and K. Gawell. 1981. A New Prosperity: Building a
Sustainable Energy Future. Andover, Mass. : Brick House Publishing
Roach, C. 1985.
Office Productivity Tools for the Information
Economy: Possible Effects on Electricity Consumption. Unpublished
f irst draft presented to Electric Power Research Institute. April.
Schmidt, P. S. 1983. The Form Value of Electricity: Some
Observations and Cases. Paper presented at the Workshop on
Electricity Use, Productive Efficiency, and Economic Growth, the
Brookings Institution, Washington, D. C. December 8-9.
Schmidt, P. S. 1984. Electricity and Industrial Productivity--A
Technical and Economic Perspective. Electric Power Research
Institute Report EM-3460. Elmsford, N.Y.: Pergamon Press.
1 ~
Representative terms from entire chapter:
technical change
