The Automotive Road to
Technological Change: Diffusion of
the Automobile as a Process of
Technological Substitution
Nakicenovic, N.
IIASA Working Paper
WP-85-019
April 1985
Nakicenovic, N. (1985) The Automotive Road to Technological Change: Diffusion of the Automobile as a Process of
Technological Substitution. IIASA Working Paper. IIASA, Laxenburg, Austria, WP-85-019 Copyright © 1985 by the
author(s). http://pure.iiasa.ac.at/2681/
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Working Paper
THE AUTOIKIWX ROAD
TO TECHIWLOGICAL CHANGE:
DIFFUSION OF THE AUTOMOBILE AS A
TECHNOLOGICAL SUBSTITUTION PROCESS
Nebojsa Nakicenovic
April 1985
WP-85-19
International Institute for Applied Systems Analysis
A-2361 Laxenburg, Austria
NOT FOR QUOTATION
WITHOUT PERMISSION
OF THE AUTHOR
TI-IE AUTOI~~T~?~'E
ROm
TO TECHE;OLOGICAL CKANGE:
DIFFUSION OF THE AUTOMOBILE AS A
TECHNOLOGICAL SUBSTITUTION PROCESS
Nebojsa Nakicenovic
April 1985
WP-85-19
Working Papers a r e interim r e p o r t s on work of t h e International
Institute f o r Applied Systems Analysis and have received only limited review. Views o r opinions expressed h e r e i n do not necess a r i l y r e p r e s e n t those of t h e Institute or of i t s National Member
Organizations.
INTERNATIONAL INSTITUTE FOR APPLIED SYSTEMS ANALYSIS
2361 Laxenburg, Austria
Forward
This working paper describes one of t h e ongoing activities in t h e study of
t h e evolution a n d development of t h e world automotive industry within t h e
IIASA Science a n d Technology Program. The r e p o r t considers t h e evolution of
t h e automobile a s a series of i n t e r l a c e d technological substitutions t h a t
changed t h e production methods a n d vehicles with a high degree of regularity.
Boris Segerstahl
Deputy Director
The Automotive Road to Technological Change:
D i f f u s i o n o f the A u t o m o b i l e as a T e c h n o l o g i c a l S u b s t i t u t i o n P r o c e s s
ABSTRACT
Advancement of t h e motor vehicle and i t s production
methods i s analyzed as a p r o c e s s of technoiogical
change. In a b r o a d e r context, motor vehicles evoiveci
as a n i n t e g r a l component of r o a d t r a n s p o r t through a
s e r i e s of i n t e r l a c e d substitutions of old by new
technologies. Buiiding on a l a r g e number of studies t h a t
d e s c r i b e d technoiogicai substitution p r o c e s s e s , f i r s t i t
i s shown how new e n e r g y forms r e p l a c e d t h e i r
p r e d e c e s s o r s a n d how t h e oici marine t r a n s p o r t
technologies were substituaed by new ones. These
examples c o n s t i t u t e some of t h e oldest, empiricaiiy
documented technoiogical changes and show t n a t many
e v e n t s in t h e dynamics of e n e r g y substitution a n d
marine t r a n s p o r t are r e l a t e d t o technological c h a n g e s
in r o a d t r a n s p o r t .
I t i s shown t h a t t h e s e substitution p r o c e s s e s c a n b e
d e s c r i b e d by simple r u i e s and t h a t t h e replacement of
aid by new technologies in t h e e n e r g y and t r a n s p o r t
systems lasted about 80 y e a r s . The technological
c h a n g e s within r o a d t r a n s p o r t , however, were more
rapid. Replacement of h o r s e s by automobiles and o l d e r
by newer generations of motor vehicles and production
methods lasted only a f e w d e c a d e s in t h e United S t a t e s .
Thus, technological substitutions within t h e r o a d
t r a n s p o r t system were considerably s h o r t e r t h a n t h e
expansion of r a i l r o a d s , s u r f a c e d r o a d s , a l l r o a d
vehicles t o g e t h e r , a n d t h e more r e c e n t expansion of a i r
transport.
TABLE OF CONTENTS
Page
1
1 INTRODUCTION
1
2 ENERGY SUBSTLTUTION
11
3 MOTOR VEHICLE OR THE HORSELESS CARRIAGE
21
4 TECHNOLOGICAL CHANGES
31
5 AUTOMOBILES AND EMISSIONS
35
6 AUTOMOBILES AND THE TRANSPORT SYSTEM
37
7 CONCLUSIONS
39
DATA SOURCES
42
BLBLIOGRAPHY
LIST OF FIGURES
2
Figure 2 . 1
P r i m a r y E n e r g y Consumption.
4
Figure 2.2
Substitution
Energy.
5
Figure 2 . 3
P r i m a r y E n e r g y Substitution.
7
Figure 2.4
Tonnage of Merchant Vessels.
8
Figure 2.5
Substitution in Merchant Vessels by Propulsion System.
8
Figure 2.6
Substitution in Merchant Vessels by S t r u c t u r a l Material.
13
Figure 3.1
Number of C a r s , Buses, and Trucks.
Figure 3.2
Road Mileage in t h e United S t a t e s .
Figure 3.3
Substitution of Unsurfaced by S u r f a c e d Roads.
Figure 3.4
Number of Non-Farm Horses (and Mules) and Cars.
Figure 3.5
Substitution of Non-Farm Horses (and Mules) b y Cars.
Figure 3.6
Actual a n d Estimated Number of Horses (and Mules) and Cars.
Figure 3.7
Actual and Estimated Number of Road Vehicles.
Figure 3 . 8
Production of Buggies ( C a r r i a g e s a n d Sulkies) and C a r s .
Figure 3.9
Substitution in Production of Buggies ( C a r r i a g e s and Sulkies)
and C a r s .
of
Fossil,
Hydro and
Nuclear f o r Renewable
Figure 3.10 Actual and Estimated Production of Road Vehicles.
Figure 4.1
Substitution in Production of Open and Closed C a r Bodies.
Figure 4.2
Substitution in Production of Factory-Installed Transmissions.
26
Figure 4.3
Substitution in Production of Drum and Disc B r a k e s .
27
Figure 4.4
Diffusion of Factory-Installed Air Conditioning.
28
Figure 4.5
Substitution of Factory-Installed Diagonal and Radial Tires.
29
Figure 4.6
Substitution in Production of Manual and Power S t e e r i n g .
32
Figure 5.1
Substitution of C a r s with Emission Controis.
34
Figure 5.2
Substitution of Leaded by Lead-Free Gasoline.
36
Figure 6.1
I n t e r c i t y P a s s e n g e r Traffic Substitution.
The Automotive Roaci to Technoiogical Change:
D i f f u s i o n o f the A u t o m o b i l e as a T e c h n o l o g i c a l S u b s t i t u t i o n P r o c e s s
1 INTRODUCTION
Analysis of t h e h i s t o r i c a l replacement of old by new technologies h a s shown
t h a t most of t h e s e p r o c e s s e s c a n b e d e s c r i b e d by simple r u l e s t h a t are c a p t u r e d in
t h e logistic substitution model ( s e e ~ a r c h e t t i ,1977; Marchetti a n d Nakicenovic,
1979; Marchetti, 1979; a n d Nakicenovic, 1984). The evolution of motor vehicles
during t h e last 100 y e a r s c a n a l s o b e s e e n as a s e r i e s of i n t e r l a c e d technological
changes of production methods a n d vehicles. I t will b e shown t h a t t h e s e c h a n g e s c a n
b e c a p t u r e d by logistic substitution anaiysis a n d t h a t t h e y h a v e o c c u r r e d with a high
d e g r e e of r e g u l a r i t y . W e will distinguish t h e substitution p r o c e s s e s in t e r m s of
annual production of motor vehicles from equivaient p r o c e s s e s at t h e level of t h e
whole f l e e t .
In o r d e r t o i i l u s t r a t e a n d d e s c r i b e t h e p r o p e r t i e s of t h e model, w e will f i r s t
give examples of how new e n e r g y forms r e p l a c e d t h e i r p r e d e c e s s o r s , s i n c e
technoiogicai c h a n g e s in t h e e n e r g y system constitute o n e of t h e f i r s t and most
complete applications of logistic substitution analysis a n d b e c a u s e many e v e n t s in
t h e dynamics of e n e r g y substitution are r e i a t e d t o technological c h a n g e s in t h e
t r a n s p o r t system. In addition, w e show some of t h e oldest documented technological
c h a n g e s within t h e t r a n s p o r t system
t h e substitution of sailing by steamships.
Since t h e United S t a t e s h a s t h e o l d e s t r e c o r d e d h i s t o r y of t h e development a n d
expansion of t h e automobiie, \ h e examples of technological c h a n g e in production
methods a n d vehicles will b e illustrated exclusively by t h e American e x p e r i e n c e .
Thus, whiie t h e r e s u l t s may apply in o t h e r industrialized c o u n t r i e s with a similarly
long h i s t o r y of motor vehicles, i t would b e n e c e s s a r y t o d e t e r m i n e whether o r not
t h e same o r equivalent r e s u l t s c a n b e obtained f o r o t h e r c o u n t r i e s .
-
2 ENERGY SiJBSTlTUTION
Analysis h a s shown t h a t t h e competitive s t r u g g l e between v a r i o u s s o u r c e s of
p r i m a r y e n e r g y obeys a r e g u i a r substitution p r o c e s s t h a t c a n b e d e s c r i b e d by
reiatively simpie r u l e s (Marchetti, 1977; Marchetti and il'akicenovic, 1979; a n d
Nakicenovic, 1979). The dynamic c h a n g e s in t h i s p r o c e s s are c a p t u r e d by logistic
equations t h a t d e s c r i b e t h e r i s e of new e n e r g y s o u r c e s and t h e decline of t h e old
ones. Figure 2 . 1 shows t h e primary e n e r g y consumption in t h e United S t a t e s since
t h e middle of t h e l a s t c e n t u r y . In addition t o fossil and n u c l e a r e n e r g y consumption,
t h e f i g u r e shows t h e u s e of m o r e traditional forms of e n e r g y during t h e l a s t c e n t u r y ,
Figure 2.1
P r i m a r y E n e r g y Consumption.
inciuaing fuel wood, ciirect u s e s of water and wind power, a n d u s e of working animais
(calcuiated in t e r m s of e n e r g y c o n t e n t of animal feed). Data are plotted on a
logarithmic s c a i e and, show exponential growth p h a s e s in consumption of t h e most
important s o u r c e s of p r i m a r y e n e r g y by piecewise-iinear, s e c u l a r t r e n d s . Thus, i t
i s evident t h a t e n e r g y consumption grew at exponential rates during long time
p e r i o d s but no o t h e r r e g u i a r i t i e s are d i r e c t l y discernable. However, t h e evolution
of p r i m a r y e n e r g y consumption e m e r g e s as a r e g u l a r substitution p r o c e s s when i t is
assumed t h a t e n e r g y s o u r c e s are d i f f e r e n t technologies competing f o r a market.
Substitution of a n old way of satisfying a given need by a new p a t h h a s b e e n t h e
s u b j e c t of a l a r g e number of studies. One g e n e r a l finding i s t h a t substitution of a n
oid technology by a new one, e x p r e s s e d in f r a c t i o n a i t e r m s , follows c h a r a c t e r i s t i c
S-shaped c u r v e s . F i s h e r and P r y (1971) formulated a v e r y simple but powerful
model of technoiogical substitution. Their model u s e s a two-parameter logistic
function t o d e s c r i b e t h e substitution p r o c e s s between two competing c o n t e n d e r s . 1
The F i s h e r a n d P r y model cannot b e usea t o d e s c r i b e t h e evoiutibn of p r i m a r y
e n e r g y consumption, s i n c e evidently more t h a n two e n e r g y s o u r c e s compete f o r t h e
m a r k e t simuitaneousiy. iiowever, w e c a n g r o u p t h e p r i m a r y e n e r g y s o u r c e s into two
b r o a d classes: t r a a i t i o n a i ( o r renewable) and c o n t e m p o r a r y (fossil, h y d r o , a n d
n u c i e a r ) forms of e n e r g y . The traditional e n e r g y s o u r c e s include fuel wood, d i r e c t
use of water a n d wind power (i.e. water a n d wind miils a n d w a t e r flotation), and
e n e r g y inputs of work animais e x p r e s s e d as t h e e n e r g y c o n t e n t of t h e f e e d consumed
(i.e. feed equivalent). The c o n t e m p o r a r y e n e r g y s o u r c e s include c o a l , c r u d e oil,
n a t u r a i gas, h y d r o e l e c t r i c power, a n d n u c l e a r e n e r g y . Figure 2.2 Hydro f o r
Renewable E n e r g y . " shows t h e t w o c l a s s e s of e n e r g y u s e in t e r m s of t h e i r r e s p e c t i v e
f r a c t i o n a l m a r k e t s h a r e s C p ) of t o t a l primary e n e r g y consumption plotted in t e r m s
of t h e quantity 'J / ( 1 -f ). The substitution p r o c e s s i s r e m a r k a b l y r e g u l a r o v e r t h e
e n t i r e time p e r i o d ( o v e r 130 y e a r s ) . The l i n e a r , s e c u l a r t r e n d s indicate t h a t t h e
substitution of t r a d i t i o n a l e n e r g y s o u r c e s by fossil, h y d r o e l e c t r i c , a n d n u c l e a r
e n e r g y c a n b e d e s c r i b e d with r e m a r k a b l e a c c u r a c y by t h e logistic function. I t is
interesting to n o t e t h a t t h e 50 p e r c e n t mark in t h e substitution p r o c e s s w a s r e a c h e d
s h o r t l y b e f o r e t h e t u r n of t h e c e n t u r y . The time c o n s t a n t of t h e substitution
p r o c e s s i s q u i t e long - more t h a n 8 0 y e a r s were r e q u i r e d b e f o r e commercial e n e r g y
s o u r c e s could c a p t u r e 50 p e r c e n t of t h e m a r k e t a f t e r t h e i r introduction at t h e onep e r c e n t m a r k e t s h a r e level back in t h e 1820s. In f a c t , t h e e m e r g e n c e of c o a l at t h e
one-percent level ( t h e f i r s t of t h e fossil e n e r g y s o u r c e s t o find widespread use)
d a t e s back t o t h e 1820s ( s e e Figure 2.3 a n d Nakicenovic, 1984, where t h e
substitution of fuel wood a n d fossil e n e r g y s o u r c e s i s t r a c e d back t o 1800),
indicating o n c e more t h e r e m a r k a b l e r e g u l a r i t y of t h e substitution p r o c e s s .
In dealing with more t h a n t w o competing technologies, w e must g e n e r a l i z e t h e
F i s h e r a n d P r y model, s i n c e in such c a s e s logistic substitution c a n n o t b e p r e s e r v e d
in all p h a s e s of t h e substitution p r o c e s s . E v e r y competitor u n d e r g o e s t h r e e distinct
substitution phases: growth, s a t u r a t i o n , a n d deciine. The growth p h a s e is similar to
t h e F i s h e r a n d P r y model of t w o competitors, but i t usually t e r m i n a t e s b e f o r e full
substitution i s r e a c h e d . I t i s followed by t h e s a t u r a t i o n p h a s e , which i s not logistic,
b u t which encompasses t h e siowing down of growth a n d t h e beginning of decline.
A f t e r t h e s a t u r a t i o n p h a s e of a technology, i t s m a r k e t s h a r e p r o c e e d s to decline
logistically.
W e assume t h a t only o n e competitor i s in t h e s a t u r a t i o n p h a s e a t a n y given time,
t h a t declining technologies f a d e away steadily at logistic rates not influenced by
competition from new competitors, a n d t h a t new c o m p e t i t o r s e n t e r t h e m a r k e t a n d
grow at logistic rates. The c u r r e n t s a t u r a t i n g competitor is t h e n l e f t with t h e
residual m a r k e t s h a r e (i.e. t h e d i f f e r e n c e between o n e a n d t h e sum of f r a c t i o n a l
m a r k e t s h a r e s of a l l o t h e r competitors) a n d i s f o r c e d to follow a nonlogistic p a t h
t h a t joins i t s p e r i o d of growth t o i t s subsequent period of decline. After t h e c u r r e n t
s a t u r a t i n g competitor h a s r e a c h e d a logistic rate of decline, t h e n e x t o l d e s t
competitor e n t e r s i t s s a t u r a t i o n p h a s e a n d t h e p r o c e s s i s r e p e a t e d until all b u t t h e
most r e c e n t competitor are in decline. In e f f e c t , o u r model assumes t h a t
1 T h e b a s i c a s s u m p t i o n p o s t u l a t e d b y F i s h e r and P r y i s t h a t once a s u b s t i t u t i o n o f t h e old b y t h e
n e w h a s p r o g r e s s e d a s f a r a s a f e w p e r c e n t , i t w i l l proceed t o c o m p l e t i o n along t h e l o g i s t i c
substitution curve:
= e x p ( a t +a)
1 -f
w h e r e t i s t h e i n d e p e n d e n t v a r i a b l e u s u a l l y r e p r e s e n t i n g s o m e u n i t o f t i m e , a and 8 a r e c o n s t a n t s ,
f i s t h e f r a c t i o n a l m a r k e t s h a r e o f t h e n e w c o m p e t i t o r , w h i l e 1 -f i s t h a t o f t h e old o n e .
f/(1-f)
Figure 2.2
fraction (f)
Substitution of Fossil, Hydro and Nuclear f o r Renewable Energy.
competitors t h a t h a v e a l r e a d y e n t e r e d t h e i r period of m a r k e t phase-out are not
influenced by t h e introduction of new ones. Deadly competition e x i s t s between t h e
s a t u r a t i n g competitor a n d all o t h e r more r e c e n t competitors ( t h e a p p r o a c h w a s
f i r s t d e s c r i b e d in Marchetti, 1977; a more comprehensive d e s c r i p t i o n of t h e model
and t h e assumptions i s given in Nakicenovic, 1979, 1984). This generalized model
o f f e r s a phenomenological description of t h e substitution p r o c e s s and h a s been
successfully applied f o r a b o u t 300 c a s e s t o d a t e , involving examples from biology,
various technological p r o c e s s e s (such as substitution of e n e r g y forms o r s t e e l
production methods), and s o on.
Figure 2.3 shows t h e p r i m a r y e n e r g y substitution f o r t h e United S t a t e s . Data
and model estimates of t h e substitution p r o c e s s a r e plotted on a logarithmic s c a l e
using t h e quantity f / (1-f) v e r s u s time (j
representing fractional market shares).
The piecewise-linear, s e c u l a r t r e n d s indicate logistic substitution phases. The
d e p a r t u r e of h i s t o r i c a i market s h a r e s from t h e i r long t e r m paths, d e s c r i b e d by t h e
logistic substitution model, sometimes l a s t s f o r o v e r two d e c a d e s only t o r e t u r n t o
t h e t r e n d a f t e r the prolonged p e r t u r b a t i o n . This i s t h e case with t h e m a r k e t s h a r e s
of coal and oil during t h e 1940s a n d 1950s, and fuel wood and animal f e e d during t h e
1860s and 1870s. This may a i s o indicate a possibie absorption of t h e d e p a r t u r e of
c o a l and n a t u r a l g a s m a r k e t s h a r e s from t h e i r iong-term p a t h s during t h e last t e n
years.
Figure 2.3
P r i m a r y E n e r g y Substitution.
The substitution p r o c e s s c l e a r l y indicates t h e dominance of c o a l as t h e major
e n e r g y s o u r c e between t h e 1870s a n d 1950s, a f t e r a long period during which fuel
wood and animai f e e a were in t h e lead. In t h e United S t a t e s , wood remaineci t h e
principal fuel for t h e r a i l r o a d s up to t h e 1870s, although r a i l r o a d s are considerod
t h e symbol of t h e c o a l a g e . The l a s t p h a s e s of r a i l r o a d expansion up to t h e 1920s,
t h e growth of s t e e l , steamships, a n d many o t h e r sectors are a s s o c i a t e d with and
based on t h e tecnnologicai o p p o r t u n i t i e s o f f e r e a by t h e m a t u r e coai economy. The
dominance of fuel wood, and l a t e r c o a l , shows a n interesting symmetry, e a c h p e r i o d
of dominance lasting 'slightly o v e r 6 0 y e a r s . After t h e 1940s, oil assumed t h e
dominant r o l e simultaneously with t h e maturing of t h e automotive, petrochemical,
and many o t h e r modern i n a u s t r i e s . I t is interesting t h a t oil r e a c h e d a one-percent
m a r k e t s h a r e a b o u t t w o d e c a d e s b e f o r e t h e f i r s t automobiles were produced in t n e
Gnited S t a t e s (actuaily f o u r were manufactured in 1895, see Epstein, 1928).
F u r t h e r , t h e f i r s t u s e of oil and n a t u r a l g a s d a t e s back to 1859, p r e c e d i n g t h e f i r s t
automobiies by aimost half a c e n t u r y .
Animal feed r e a c h e d i t s highest m a r k e t s h a r e in t h e 1880s, indicating t h a t d r a f t
animals provided t h e major form of local t r a n s p o r t a t i o n and motive power in
a g r i c u l t u r e , d e s p i t e t h e dominance of r a i l r o a d s and steamships as long-distance
t r a n s p o r t modes. H o r s e c a r r i a g e s and wagons were t h e only form of local t r a n s p o r t
in r u r a l areas a n d basically t h e only f r e i g h t t r a n s p o r t mode in cities. In addition,
t h e y moved goods and people to and from r a i l r o a d s a n d h a r b o r s . I t i s c u r i o u s t h a t
t h e feed and c r u d e oil substitution c u r v e s c r o s s in t h e 1920s, as if to suggest t h e
simultaneous substitution of t h e h o r s e c a r r i a g e a n d wagon by t h e motor vehicle t h a t
will b e d e s c r i b e d below. Figure 2.3 p r o j e c t s n a t u r a l g a s as t h e dominating e n e r g y
s o u r c e a f t e r t h e 1980s, although c r u d e oil s t i l l maintains a b o u t a 3 0 p e r c e n t m a r k e t
s h a r e by t h e end of t h e c e n t u r y . Nevertheless, t h e p r o j e c t e d dominance of n a t u r a l
g a s may imply c h a n g e s in t h e kind of automobile propulsion systems t h a t c a n b e
e x p e c t e d in t h e l o n g e r t e r m f u t u r e (beginning of t h e twenty-first c e n t u r y ) .
Certainiy enough c r u d e oil would b e available f o r gasoline distillation, but t h e
importance of n a t u r a l g a s indicates t h e possibility of e i t h e r d i r e c t u s e of n a t u r a l
g a s in t h e t r a n s p o r t sector or i t s transformation into s y n t h e t i c fuels, s u c h as
methanol.
The logistic substitution model indicates t h a t i t i s possible to d e s c r i b e t h e
b r o a d f e a t u r e s of t h e evolution of t h e e n e r g y system in t h e United S t a t e s o v e r v e r y
long p e r i o d s of time by r a t h e r simple mechanisms, d e s p i t e many t u r b u l e n t a n d
profound c h a n g e s during t h e last 1 3 0 y e a r s . More importantly, t h e s e c h a n g e s are
p a r a l l e l e d by transformations of t h e t r a n s p o r t system, from sailing s h i p s a n d animal
drawn vehicles to steamships a n d r a i l r o a d s , a n d later to motor vehicles a n d a i r
t r a n s p o r t . Before r e t u r n i n g to t h e analysis of technological c h a n g e of t h e
automobile, w e will f i r s t c o n s i d e r t h e substitution p r o c e s s in t h e m e r c h a n t f l e e t of
t h e United S t a t e s , s i n c e t h i s example i l l u s t r a t e s t h e evolution of o n e of t h e o l d e s t
modes of t r a n s p o r t . The automobile i s b a r e l y 1 0 0 y e a r s old, whereas t h e r e c o r d e d
c h a n g e s e n c o u n t e r e d in t h e evolution of t h e merchant f l e e t c o v e r a p e r i o d of 200
y e a r s a n d include a fundamental transformation of propulsion systems, i n c r e a s e d
s p e e d a n d s i z e of t h e vessels, a n d c h a n g e s in t h e construction methods a n d
materials.
The t r a d i t i o n a l s h i p propuision, in u s e e v e r s i n c e a n c i e n t times, w a s wind power
a n d t h e traditional c o n s t r u c t i o n m a t e r i a l w a s wood. With t h e development of t h e
steam engine a n d t h e r e i a t i v e i y high e n e r g y density of hign-quality coais, i t w a s
possible to slowly r e p l a c e s a i l s with steam engines. The f i r s t designs w e r e of a
h y b r i d t y p e employing both steam and wind power. With t h e i n c r e a s e in t h e s i z e of
vessels, along with t h e expansion of o v e r s e a s t r a d e , and with t h e growth of t h e i r o n
and steel industries, wood w a s increasingly substituted by i r o n a n d l a t e r by steel as
t h e basic construction material. In f a c t , t h e number of vessels remained p r a c t i c a l l y
c o n s t a n t between t h e end of t h e eighteenth c e n t u r y and t h e 1940s at a b o u t 25,000
ships, doubling to almost 50,000 d u r i n g t h e l a s t t h r e e d e c a d e s u p to 1970. During
t h e same p e r i o d of almost t w o c e n t u r i e s t h e t o t a l r e g i s t e r e d tonnage of t h e
m e r c h a n t f l e e t i n c r e a s e d by almost t w o o r d e r s of magnitude, implying t h a t t h e
a v e r a g e vessei i s a b o u t 1 0 0 times l a r g e r today t h a n in 1800. This enormous
i n c r e a s e in t h e tonnage c a p a c i t y of a n a v e r a g e vessel c a n only b e explained by
continuous improvements in propulsion systems, c o n s t r u c t i o n materials, and design.
Figure 2.4 shows t h e tonnage growth of t h e m e r c h a n t fleet in t h e United S t a t e s
s i n c e 1789 a n d Figure 2 . 5 shows t h e substitution of sailing by steamships, both coal
a n d oil f i r e d , a n d l a t e r t h e m a r k e t p e n e t r a t i o n of motor, diesel, a n d semi-diesel
s h i p s in t e r m s of t h e i r r e s p e c t i v e tonnage. Sailing s h i p s dominated t h e m e r c h a n t
fleet until t h e 1880s, although s t e a m e r s a c q u i r e d a one-percent s h a r e of t h e t o t a l
tonnage in 1819, more t h a n half a c e n t u r y e a r l i e r ( a t t h e same time a s coal r e a c h e d
a o n e - p e r c e n t s h a r e in p r i m a r y e n e r g y ) . By t h e 1920s steam vessels constituted
more t h a n 9 0 p e r c e n t of m e r c h a n t tonnage, t h u s t h e replacement of t h e traditional
sailing s h i p lasted almost LOO y e a r s . During t h e same d e c a d e motor s h i p s were
introduced a n d t h e i r s h a r e of total tonnage h a s i n c r e a s e d e v e r s i n c e , although even
today t h e y h a v e not a c q u i r e d much more t h a n o n e t e n t h of t h e fleet tonnage.
Consequently, steamships a r e s t i l l a n important t y p e of merchant vessel and a r e
nllllon Tons
Figure 2.4
Tonnage of Merchant Vessels.
Figure 2.5
Substitution in Merchant Vessels by Propulsion System.
p r o j e c t e d in Figure 2 . 5 t o remain so until t h e end of t h e twentieth c e n t u r y , although
today t h e y are fueled by oil a n d in some c a s e s use steam t u r b i n e s instead of coaif i r e d atmospheric engines. During World War, t h e s h a r e of motor s h i p s s h a r p l y
i n c r e a s e d a n d accordingiy t h e s h a r e of s t e a m e r s w a s below t i e long-term t r e n d
during t h i s period. But t h e s e p e r t u r b a t i o n s were r e a b s o r b e d d u r i n g t h e 1960s t o
r e t u r n t o t h e long-term t r e n d indicated by t h e logistic substitution model.
Figure 2.6 shows t h e s h a r e of wood a n d metal s h i p s in t h e m e r c h a n t f l e e t of t h e
United S t a t e s . The r e p l a c e m e n t of wooden s h i p s w a s a r a t h e r r a p i d p r o c e s s t h a t
s t a r t e d soon a f t e r t h e introduction of Bessemer steelmaking in 1857. The f i r s t metal
s h i p s were made o u t of i r o n , but later steel w a s a l s o used. The d a t a are not
available f o r t h e p e r i o d b e f o r e 1885, so w e c a n only e x t r a p o l a t e ("backcast"), using
t h e logistic substitution model, t h a t metal s h i p s achieved t h e one-percent s h a r e
a r o u n d t h e y e a r 1850. By 1910 half of all merchant tonnage consisted of metal s h i p s
a n d today virtually all s h i p s a r e made out of metal.
f/( 1-f)
Figure 2.6
froctlon (f)
Substitution in Merchant Vessels by S t r u c t u r a l Material.
The a b o v e applications of t h e logistic substitution model to t h e h i s t o r i c a l
replacement of o l d e r by newer f o r m s of e n e r g y a n d propulsion of m e r c h a n t vessels
indicate t h a t improvements a n d growth a r e a c h i e v e d through a r e g u l a r , b u t
discontinuous, p r o c e s s a n d t h a t new e n e r g y a n d marine propulsion technologies
needed more t h a n 8 0 y e a r s t o r e p l a c e o n e half of t h e o l d e r competing technology.
From t h e time of i t s f i r s t commercial use, e a c h new technology grows logistically
until i t r e a c h e s a s a t u r a t i o n p h a s e a n d t h e n p r o c e e d s to decline logistically while
being r e p l a c e d by a newer a n d m o r e promising technology. During e a c h p h a s e of
t h e substitution p r o c e s s t h e dominant technology a p p e a r s to b e s t r o n g and
unassailable, but with time i t d e c a y s as emerging competitors "attack" t h e newly
exposed position of t h e m a t u r e technology. I t i s i n t e r e s t i n g to n o t e t h a t t h e
s a t u r a t i o n point is not, by and l a r g e , determined by m e r e physical or r e s o u r c e
limitations, b u t r a t h e r t h r o u g h t h e dynamics of t h e introduction of new technologies.
Thus, t h e m a r k e t s h a r e s i n c r e a s e until limits are e n c o u n t e r e d t h a t a p p e a r to b e
endogenous to t h e m a r k e t ( o r system) itself. These limits are e n c o u n t e r e d b e f o r e
complete m a r k e t t a k e o v e r .
3 MOTOR YEHlCLE OR THE HORSELESS CARFUAGE
The f i r s t motor vehicles were c u r i o s a n d v e r y few p r o p o n e n t s of t h e automobile
envisaged i t s r a p i d development a n d dissemination t h r o u g h o u t t h e world during t h e
twentieth c e n t u r y . In t h e United S t a t e s t h e f i r s t h o r s e l e s s c a r r i a g e s posed a n
a l t e r n a t i v e to t h e horse-drawn buggies a n d wagons. Especialiy as a commercial
vehicle, t h e motor car o f f e r e d many potential advantages. P e r h a p s t h e most
important w a s t h e possibility to i n c r e a s e t h e r a d i u s of local t r a n s p o r t compared
with horse-drawn vehicles. In t h e 1930s t h e a v e r a g e d i s t a n c e t r a v e i e d p e r d a y by
horse-drawn vehicles w a s between 1 0 a n d 20 miles a n d t h a t b y motor vehicles w a s 3 5
a n d more miles p e r day. Because t h e automobile w a s f a s t e r i t allowed many
e n t r e p r e n e u r s to expand t h e i r c i r c l e of c u s t o m e r s a n d o f f e r e d a m o r e flexibie mode
of l e i s u r e and business t r a n s p o r t . Also, r a i l r o a d s w e r e not cnalienged by t h e
beginning of t h e automobile a g e , but r a t h e r helped t h e expansion of motor vehicles
s i n c e t h e y o f f e r e d a n efficient form of long-distance t r a n s p o r t t h a t combined w e l l
with motor vehicles as t h e local, u r b a n , a n d r u r a l r o a d t r a n s p o r t . Within a few
d e c a d e s t h e automobile became a n important form of t r a n s p o r t in t h e United S t a t e s
and s t a r t e d also to compete with r a i l r o a d s , especially f o r long-distance p a s s e n g e r
t r a v e l . S i n c e .the 1 9 3 0 s up to t h e p r e s e n t , t h e total mileage t r a v e l e d by
automobiles, a n d motor vehicles in g e n e r a l , w a s divided almost equally between
r u r a l and urban travel.
E a r l y motor vehicles resembled horse-drawn buggies a n d wagons s i n c e most of
t h e r u r a l r o a d s w e r e not paved. L a r g e spoked wheels, high r o a d c l e a r a n c e , a n d a
wooden body c h a r a c t e r i z e d both horse-drawn buggies a n d wagons a n d motor cars.
All told, o u r initial working hypothesis is t h a t in t h e United S t a t e s t h e automobile
f i r s t displaced t h e horse-drawn vehicle. Only a f t e r t h e completion of t h i s
substitution p r o c e s s did i t e m e r g e as a n important t r a n s p o r t a t i o n mode in
competition with t h e r a i l r o a d f o r long-distance movement of p e o p l e a n d goods a n d
p e r h a p s also as a competitor to u r b a n t r a n s p o r t a t i o n modes, s u c h as t h e t r a m o r
local t r a i n . T h e r e f o r e , w e will divide t h e evolution of t h e motor vehicle in t h e
United S t a t e s into t w o p h a s e s
t h e f i r s t p h a s e encompasses t h e substitution of
h o r s e s a n d animal-drawn vehicles and t h e second p h a s e m a r k s a widespread
diffusion of t h e individual t r a n s p o r t b a s e d o n t h e motor vehicle, a f t e r o t h e r
vehicles essentially d i s a p p e a r e d from American roads.
-
The automobile had a r e l a t i v e l y late start in t h e United S t a t e s compared with
E u r o p e a n c o u n t r i e s . Certainly, no single individual c a n b e c r e d i t e d with i t s
invention. Steam motor vehicles emerged in t h e e a r l y nineteenth c e n t u r y , b u t t h e
f i r s t p r o t o t y p e s with i n t e r n a l combustion engines a p p e a r e d in t h e 1880s. K a r l Benz
w a s p r o b a b l y t h e f i r s t to design and build a fully functional motor car based o n a
t u b u l a r f r a m e a n d a single-cylinder i n t e r n a l combustion engine ( r a t e d at 1.5 h o r s e
power allowing s p e e d s of up to 1 6 km/h). O t h e r designs of t h e time were limited to
transplanting engines to vehicles designed f o r o t h e r p u r p o s e s . Be t h a t as i t may,
t h e f i r s t motor vehicles t h a t a p p e a r e d in t h e United S t a t e s d u r i n g t h e 1890s
included both American a n d E u r o p e a n designs. In 1 8 9 5 f o u r motor vehicles w e r e
r e c o r d e d to b e in u s e in t h e United S t a t e s . The initial expansion of t h e automobile
w a s v e r y impressive - 1 6 vehicles were in u s e a y e a r later, 9 0 in 1897, 8000 in 1900,
almost half a million t e n y e a r s later a n d more t h a n o n e million a f t e r a n o t h e r t w o
y e a r s . Both in t e r m s of production a n d number of vehicles in use, t h e United S t a t e s
quickly s u r p a s s e d E u r o p e a n c o u n t r i e s . F o r example, Germany p r o d u c e d a b o u t 800
motor vehicles in 1900, F r a n c e a b o u t 3000, a n d t h e United S t a t e s more t h a n 4000.
By 1922 m o r e t h a n t e n million motor vehicles were in u s e o n American r o a d s a n d t h e
100 million mark w a s s u r p a s s e d in 1970. In 1 9 8 3 1 2 5 million automobiles, 0.6 million
buses, a n d 35 million t r u c k s were r e g i s t e r e d in t h e United S t a t e s . Figure 3.1 shows
t h e total r e g i s t r a t i o n s of c a r s , buses, and t r u c k s in t h e United S t a t e s since 1895.
The expansion of motor vehicle f l e e t s i s c h a r a c t e r i z e d by t w o , distinct s e c u l a r
t r e n d s with a n inflection in t h e 1930s f o r cars and t r u c k s a n d a less pronounced
inflection in t h e 1950s f o r buses. S i n c e t h e t w o s e c u l a r t r e n d s of e a c h c u r v e a p p e a r
t o b e roughly l i n e a r on t h e logarithmic s c a l e in Figure 3.1, t h e motor vehicle f l e e t s
evolved t h r o u g h t w o exponential pulses. In a c c o r d a n c e with o u r working hypothesis
w e contend t h a t t h e two exponential t r e n d s indicate t w o d i f f e r e n t p h a s e s of
dissemination of motor v e h i c l e s in t h e United S t a t e s . The f i r s t c h a r a c t e r i z e s t h e
substitution of horse-drawn r o a d vehicles and t h e second t h e a c t u a l growth of r o a d
t r a n s p o r t at l a r g e . Thus, t h e f i r s t expansion p h a s e i s more r a p i d s i n c e it
r e p r e s e n t s a "market t a k e o v e r " , w h e r e a s t h e second r e p r e s e n t s t h e a c t u a l growth
of t h e r o a d vehicle f l e e t s a n d t h e associated i n f r a s t r u c t u r e s u c h as t h e highway
system.
Sometimes i t i s s a i d t h a t t h e automobile c a u s e d t h e need f o r good r o a d s ,
sometimes t h a t t h e c o n s t r u c t i o n of good r o a d s c a u s e d t h e g r e a t development of t h e
automobile industry (see, e.g. Epstein, 1928). Actually, t h e expansion of t h e r o a d
vehicle f l e e t s is p a r a l l e l e d by t h e growth of s u r f a c e d r o a d s mileage, while t h e total
mileage of a l l r o a d s i n c r e a s e d v e r y slowly from 3.16 million miles in 1 9 2 1 to 3.85
million miles in 1981. F i g u r e 3.2 shows t h e t o t a l r o a d mileage in t h e United S t a t e s
a n d t h e mileage of u r b a n streets ( e a r l i e r defined as municipal s t r e e t s ) , r u r a l r o a d
mileage a n d mileage of all u r b a n and r u r a l s u r f a c e d r o a d s (bituminous p e n e t r a t i o n ,
a s p h a l t , c o n c r e t e , wood, s t o n e , a n d o t h e r ) . The f i g u r e i l l u s t r a t e s t h a t t h e growth of
s u r f a c e d r o a d mileage p a r a l l e l e d t h e growth of t h e motor vehicle f l e e t s a f t e r t h e
1930s. However, t h e expansion of s u r f a c e d r o a d s p r e c e d e d t h e expansion of motor
vehicles. In 1 9 0 5 e i g h t p e r c e n t of all r o a d s were s u r f a c e d , but l e s s t h a n 80,000
motor vehicles were used compared to a b o u t 3.3 million non-farm h o r s e s a n d mules
(22 million d r a f t animals were used f o r farming). Thus, e a r l y r o a d s were developed
f o r h o r s e s and not automobiles, but motor vehicles expanded quickly into t h e
growing i n f r a s t r u c t u r e of s u r f a c e d r o a d s . Figure 3.3 shows t h e substitution of
unsurfaced by s u r f a c e d r o a d s . In 1910 a b o u t 1 0 p e r c e n t of a l l r o a d s were s u r f a c e d ,
during t h e 1 9 4 0 s a b o u t o n e h a l f , a n d today a b o u t 90 p e r c e n t are s u r f a c e d , so t h a t in
This i s a b o u t t h e
r e t r o s p e c t t h e substitution p r o c e s s lasted l o n g e r t h a n 75 y e a r s .
same time c o n s t a n t as o b s e r v e d f o r t h e r e p l a c e m e n t of propulsion systems in t h e
m e r c h a n t f l e e t and p r i m a r y e n e r g y substitution in t h e United S t a t e s . P r o j e c t i n g
t h i s substitution p r o c e s s into t h e f u t u r e indicates t h a t by t h e end of t h e c e n t u r y
virtually a l l r o a d s will b e s u r f a c e d . T h e r e f o r e , w e c a n conclude t h a t t h e
introduction of s u r f a c e d r o a d s p r e c e d e d t h e introduction of motor vehicles in t h e
United S t a t e s , but t h a t t h e f i r s t rapid-growth p h a s e of motor vehicle f l e e t s
o c c u r r e d while less t h a n o n e half of American r o a d s were s u i t a b l e f o r t h e i r use. I t
i s a l s o i n t e r e s t i n g to n o t e t h a t t h e substitution p r o c e s s d o e s not r e f l e c t t h e
vigorous r o a d c o n s t r u c t i o n e f f o r t a f t e r t h e d e p r e s s i o n y e a r s in t h e United S t a t e s ,
b u t r a t h e r indicates a lack of s u c h e f f o r t during t h e 1 9 1 0 s and 1 9 2 0 s b e c a u s e t h e
a c t u a l expansion of s u r f a c e d mileage i s somewhat below t h e long-term t r e n d during
t h e s e t w o decades. A similar underexpansion o c c u r r e d during t h e e a r l y 1970s, b u t
a p p e a r s to h a v e been r e a b s o r b e d during t h e last few y e a r s .
2 The growth of s u r f a c e d r o a d s mileage can be d e s c r i b e d w e l l w i t h a l o g i s t i c growth c u r v e t h a t h a s
an i n f l e c t i o n point i n 1947, growth r a t e o f 7.63 p e r c e n t per y e a r , and a s a t u r a t i o n l e v e l o f 3 . 4 2
million m i l e s . T h i s i s i n good agreement w i t h t h e s u b s t i t u t i o n p r o c e s s of s u r f a c e d f o r o t h e r
roads, g i v e n i n F i g u r e 3.3, b e c a u s e t h e t o t a l road mileage h a s remained a l m o s t c o n s t a n t during t h e
l a s t 80 y e a r s .
1000 Units
Figure 3.1
Number of C a r s , Buses, and T r u c k s .
Due to t h e obvious problems a s s o c i a t e d with t h e lack of h i s t o r i c a l r e c o r d s
a b o u t t h e e x a c t number of horse-drawn vehicles in t h e United S t a t e s during t h e f i r s t
d e c a d e s a f t e r t h e introduction of t h e automobile in 1895, w e c a n only approximately
d e s c r i b e t h e assumed substitution of h o r s e drawn vehicles by t h e motor c a r during
t h e f i r s t , more r a p i d , expansion p h a s e of t h e motor vehicle f l e e t s . A s a rough
9
rural
Figure 3.2
Road Mileage in the United States.
f/( 1-f)
Figure 3.3
fraction (f)
Substitution of Unsurfaced by Surfaced Roads.
approximation of t h i s substitution p r o c e s s , we u s e t h e number of d r a f t animals and
motor vehicles given in Figure 3.4.
Figure 3.4
Number of Non-Farm Horses (and Mules) and C a r s .
Sometimes h o r s e a n d saddle were used a s a "road vehicle", but o f t e n m o r e t h a n
o n e h o r s e w a s used t o pull buggies and wagons, so t h a t Figure 3 . 4 may
overemphasize t h e number of horse-drawn vehicles if t h e number of d r a f t animals is
used as a p r o x y f o r t h e number of vehicles actually in use. N e v e r t h e l e s s , w e will
make t h i s assumption in o r d e r to analyze t h e postulated substitution p r o c e s s .
Figure 3.5 shows t h e substitution of non-farm h o r s e s a n d mules by c a r s . Thus, w e
implicitly assume t h a t t h e number of non-farm h o r s e s a n d mules c o r r e s p o n d s to t h e
number of animal-drawn r o a d vehicles. C a r s r e p r e s e n t all r e g i s t e r e d motor
vehicles, omitting t r u c k s a n d b u s e s from Figure 3.1.
The disadvantage of t h i s rough comparison of numbers of animal-drawn vehicles
a n d motor c a r s i s t h a t t h e estimates of t h e number of non-farm h o r s e s anci mules are
c e r t a i n l y n o t v e r y a c c u r a t e a n d t h a t t h e y are unevenly s p a c e d in time. Thus, annuai
fluctuations of t h e a c t u a l number of d r a f t animals cannot b e r e c o n s t r u c t e d from t h e
available h i s t o r i c a l r e c o r d s . Despite t h e s e disadvantages, Figure 3 . 5 indicates t h a t
t h e automobile r e p l a c e d h o r s e - and mule-drawn r o a d vehicles d u r i n g a r e i a t i v e l y
Figure 3.5
Substitution of Non-Farm H o r s e s (and Mules) by Cars.
s h o r t period a n d t h a t t h e substitution p r o c e s s p r o c e e d e d along a logistic p a t h .
Motor vehicles achieved a one-percent s h a r e in r o a d vehicles s h o r t l y a f t e r 1 9 0 0
and a 5 0 p e r c e n t s h a r e in 1917. The complete t a k e o v e r of t h e "market" f o r r o a d
vehicles ocs:lrred in 1 9 3 0 with 2 3 million cars in use a n d 0 . 3 million non-farm h o r s e s
a n d mules. This r e s u l t indicates t h a t t h e inflection point of t h e s e c u l a r t r e n d of
r e g i s t e r e d cars from F i g u r e s 3.1 a n d 3.4 actually coincides with t h e end of t h e
substitution of animal-drawn r o a d vehicles. This r e s u l t also explains t h e
"saturation" of motor vehicles in t h e United S t a t e s p e r c e i v e d by many a n a l y s t s
d u r i n g t h e l a t e 1920s a n d e a r l y 1930s. However, t h e p e r c e i v e d s a t u r a t i o n of cars
w a s actually t h e e n d of t h e substitution of animal-drawn vehicles a n d t h e beginning
of a new p h a s e in t h e motorization of America, with growth rates comparable t o
t h o s e of t h e expansion of h o r s e c a r r i a g e s and wagons b e f o r e t h e automobile a g e .
S e e n from t h i s p e r s p e c t i v e , t h e growth in t h e total number of r o a d vehicles is a
continuous p r o c e s s without a n y pronounced c h a n g e s o v e r t h e e n t i r e p e r i o d from
1850 to d a t e , with a n a v e r a g e annual growth rate of a b o u t 4.2 p e r c e n t . Figure 3.6
shows t h e number of non-farm h o r s e s a n d mules a n d cars from Figure 3.4, t o g e t h e r
with t h e estimates from t h e logistic substitution model based on a 4.2 p e r c e n t p e r
y e a r growth of t h e "market" f o r all r o a d vehicles, while Figure 3.7 shows t h e growth
of all r o a d vehicles by summing t h e number of h o r s e s , mules, a n d automobiles.
Although t h i s r e s u l t s t r e n g t h e n s o u r working hypothesis of t w o d i f f e r e n t p h a s e s
in t h e dissemination of t h e automobile, i t is by no means conclusive d u e to t h e r o u g h
approximation of t h e number of r o a d vehicles drawn by h o r s e s and mules. I t should
a l s o b e o b s e r v e d t h a t t h e smooth growth of all r o a d vehicles c o r r e s p o n d s well to t h e
continuous growth of s u r f a c e d r o a d s in t h e United S t a t e s during t h e last 8 0 y e a r s .
Figure 3.6
Actual a n d Estimated Number of Horses (and Mules) a n d C a r s .
By t h e time h o r s e s d i s a p p e a r e d from t h e American r o a d s o n e haif of t h e r o a d s were
s u r f a c e d and t h e r e a f t e r annual construction r a t e s of new s u r f a c e d r o a d s declined.
Thus, while t h e i n f r a s t r u c t u r a l c n a n g e of t h e American r o a d system took almost as
long as t h e substitution of m e r c h a n t f l e e t s and p r i m a r y e n e r g y , t h e substitution of
vehicle f l e e t s was a much swifter p r o c e s s lasting only t h r e e decades.
The n e x t example s e r v e s to v e r i f y t h i s r e s u l t by independent observations.
Figure 3.8 shows t h e production of buggies (including c a r r i a g e s a n d sulkies) a n d
f a c t o r y s a l e s of motor c a r s in t h e United S t a t e s . W e h a v e not e x t e n d e d t h e c u r v e s
beyond 1950 s i n c e t h e f a c t o r y s a l e s ( o r production) of motor vehicles cease to b e a
good p r o x y f o r a c t u a l vehicle s a l e s d u e to t h e emerging importance of imports.
Because of t h e s c r a p p i n g rates of r o a d vehicles, t h e two c u r v e s d o n o t e x a c t l y
r e p r e s e n t "derivatives" of t h e a c t u a l number of r o a d vehicles in use. Nevertheless,
t h e y exhibit t r e n d s similar to t h e number of non-farm h o r s e s (and mules) and
r e g i s t e r e d cars. In f a c t , t h e s e c u l a r t r e n d of motor car production shows a n
inflection during t h e 1920s p r e c e d i n g t h e similar inflection in t h e growth of t h e
automobile f l e e t by less t h a n t e n y e a r s . Figure 3.9 shows t h e substitution p r o c e s s in
production of buggies, c a r r i a g e s , and sulkies ( r e p r e s e n t i n g animal drawn r o a d
vehicles) a n d f a c t o r y s a l e s of motor c a r s . This substitution p r o c e s s confirms t h e
r e s u l t s from t h e p r e v i o u s example. Automobile manufacture achieved a one-percent
s h a r e in t h e production of r o a d vehicles s h o r t l y a f t e r 1900, a 5 0 p e r c e n t market
s h a r e in 1914, and by 1924 virtually all r o a d vehicles p r o d u c e d (i.e. sold) in t h e
United S t a t e s were automobiles. Thus, t h e m a r k e t t a k e o v e r in production p r e c e d e s
t h e t a k e o v e r in t h e vehicie f l e e t s by a b o u t six y e a r s . This may b e d u e t o t h e l o n g e r
-
Figure 3.7
- -
-
Actual and Estimated Number of Road Vehicles.
life s p a n of animal-drawn vehicles compared t o c a r s ; however t h i s is only a
speculation since t h e s t a t i s t i c s are not available. The lag of a b o u t six y e a r s
between t h e substitution of vehicle f l e e t s and vehicle production indicates t h a t t h e
a v e r a g e a g e of a l l r o a d vehicles could have been about six y e a r s by t h e 1930s,
which i s in a good a g r e e m e n t with t h e a v e r a g e a g e of 5.5 y e a r s f o r cars (and 5.6
y e a r s f o r t r u c k s ) in 1 9 4 1 ( e a r l i e s t y e a r f o r which t h e d a t a were available, see
Automobile Facts and Figures, 1971). Nevertheless, in both examples t h e major
deviations from t h e logistic substitution p a t h s o c c u r toward t h e complete
replacement of horse-drawn vehicles. In g e n e r a l , o l d e r technologies tend t o s e r v e
r e c r e a t i o n a l o r a e s t h e t i c r o l e s o n c e t h e replacement i s complete. This w a s t h e c a s e
with fuel wood, sailing snips, h o r s e s , convertible (open) c a r s , and many o t h e r
exampies. Thus, i t i s conceivable t h a t t h e d e p a r t u r e s of t h e a c t u a l m a r k e t s n a r e s
from t h e i r logistic p a t h s could b e r e d u c e d toward t h e end of t h e substitution
p r o c e s s by eliminating t h i s "non-substitutable" niche f o r o l d e r technologies from
t h e analysis.
Given t h e p o o r quality of historical r e c o r d s , i t i s obvious t h a t t h e two examples
give a consistent description of t h e introduction of t h e automobiie as a n a l t e r n a t i v e
t o o i d e r r o a d vehicles. F u r t h e r m o r e , Figure 3.10 shows t h a t t h e production of a l l
r o a d vehicles ( c a r r i a g e s , buggies, sulkies, and motor c a r s ) grew with a constant
a v e r a g e annual growth rate of a b o u t 3.1 p e r c e n t between 1900 and 1950 without a
change in t h e s e c u l a r t r e n d .
Figure 3.8
Production of Buggies ( C a r r i a g e s and Sulkies) a n d Cars.
I t i s i n t e r e s t i n g t o note t h a t by t h e time t h e automobile h a d substituted t h e
horse-drawn vehicles (during t h e 1920s), fundamental technologicai c h a n g e s in
production had o c c u r r e d as well. These c h a n g e s were p r o b a b l y a n important f a c t o r
in f u r t h e r diffusion of t h e automobile o n c e it became t h e exclusive means of r o a d
tr?.nsport, by making i t m o r e r e i i a b l e , c h e a p e r to p u r c h a s e a n d maintain, and e a s i e r
to operate.
- --
fraction (f)
Figure 3.9
Substitution in Production of Buggies ( C a r r i a g e s and Sulkies) a n d C a r s .
1 0 0 0 units
Figure 3.10 Actual and Estimated Production of Road Vehicies.
4 TECHNOLOGICAL CHANGES
It is usually v e r y difficult t o distinguish between technological cnanges in t h e
production of motor vehicles and changes in t h e vehicles themselves. These changes
went hand in hand: new design a n d performance c h a r a c t e r i s t i c s imposed changes in
production and new production p r o c e s s e s made changes in t h e vehicies possible. In
1914 when Ford introduced t h e moving assem'oly (by a n analogy t o t h e moving
"disassembly" in a Chicago slaughterhouse), a b o u t as many horse-drawn vehicles
were produced as automobiles ( s e e Figure 3.8). Abernathy (1978) points o u t t h a t
a n o t h e r t e n y e a r s went by b e f o r e techniques f o r t h e mass production of car bodies
were rapidly deveiopea. They couid not b e applied successfully, in s p i t e of moving
assembly methods, as long as wooden construction materials were used. A s if
symboiically, wooden bodies were used in almost a i l models ( e x c e p t a few high-price
vehicles) throughout t h e 1920s a n d from t h i s point of view were no d i f f e r e n t from
c a r r i a g e s . By t h e time t h e automobile became t h e main mode of r o a d t r a n s p o r t ,
major m a n u f a c t u r e r s were producing s t e e l bodies. This went hand in hand with t h e
introduction of closed bodies t h a t depended upon advances in t h e widths and s u r f a c e
finish of rolled s t e e l , t h e development of welding technology, and new paints a n d
painting methods (Abernathy, 1978).
Once t h e s e changes were introduced into t h e moving assembly, mass-production
techniques emerged a n d new methods of sheet-metal forming with p r e s s e s a n d
welding were n e c e s s a r y . A moving assembly of metal bodies w a s based not on s h e e t metal forming, but primarily on machining o r metal removal, and w a s t h u s similar t o
t h e f i r s t form of moving assembly f o r wooden bodies.
Figure 4 . 1 shows t h e substitution of o p e n by closed c a r bodies. This
substitution p r o c e s s c a n b e considered a p r o x y f o r c h a n g e s in production
techniques a n d t h e replacement of wood by s t e e l in automobiles in t h e United S t a t e s .
In 1915 closed bodies a c q u i r e d a one-percent market s h a r e in t o t a l production, only
a y e a r a f t e r Ford introduced t h e moving assembly. Ten y e a r s l a t e r 5 0 p e r c e n t of a l l
cars were sold with closed bodies and by t h e middle 1930s t h e y were universal,
leaving only a small segment of t h e m a r k e t t o convertibles. All told, t h e diffusion of
fundamental c h a n g e s in automobile manafacturing and design o c c u r r e d a f t e r most of
t h e traditional r o a d vehicles had been r e p l a c e d by automobiles a n d w a s concluded
by t h e time o n e half of American r o a d s were s u r f a c e d .
Up t o t h e late 1920s most automobiles were literally h o r s e l e s s c a r r i a g e s a n d
probably did not need t o b e much more since, as such, t h e y were inherently s u p e r i o r
t o c a r r i a g e s . However, t o a c q u i r e new customers, o n c e t h e h o r s e had aimost
d i s a p p e a r e d from American r o a d s , t h e automobile needed t o fulfill functions besiaes
individual t r a n s p o r t in t h e c r u d e s t s e n s e of t h e word. Epstein (1928) classified t h e
p u r p o s e s f o r which automobiles were bought during t h e 1920s into f o u r main
categories: t r a n s p o r t a t i o n s e r v i c e , s p o r t , personal possession, a n d social p r e s t i g e .
The fulfillment of t h e s e f o u r a n d probably o t h e r c r i t e r i a placed on t h e automobile
implied t h e necessity f o r l a r g e improvements. Most importantly, t h e automobile had
t o become e a s i e r t o u s e and more reliable. Both of t h e s e improvements were
realized through technological changes. Reliability w a s achieved mostly through
b e t t e r materials, design, and machining. Convenience, however, necessitated
f u r t h e r changes: t h e e l e c t r i c s e l f - s t a r t e r , e l e c t r i c lights, low-pressure pneumatic
t i r e s , closed, metal bodies, and s o on. I t a p p e a r s t h a t t h e period s t a r t i n g in t h e l a t e
1920s marked a c e r t a i n tendency toward reconsolidation a n d increasing
lo"
Figure 4 . 1
Substitution in Production of Open and Closed C a r Bodies.
homogeneity in t h e industry. While automobile design and prociuction methods v a r i e d
widely during t h e p h a s e of h o r s e and c a r r i a g e substitution, during t h e 1930s most
manufacturers adopted moving assembly methods and basically similar designs. Most
of t h e "unconventional" vehicles d i s a p p e a r e d , including steam and e l e c t r i c cars. A t
t h e same time, t h e "conventional" automobile and production improvements
disseminated throughout t h e industry, making p r c d u c t differentiation n e c e s s a r y a s a
replacement f o r genuine a l t e r n a t i v e s . Another way of phrasing t h i s new f e a t u r e of
t h e automotive industry i s t h a t successful innovations disseminated r a t h e r quickly
and o n c e adopted were improved r a t h e r t h a n r e p l a c e d by most firms as if t o r e d u c e
t h e r i s k of making c h a n g e s which might not b e t o t h e customer's liking. Examples
include t h e diffusion of four-wheel b r a k e s and low-pressure balloon t i r e s . In 1923 a
little more t h a n o n e p e r c e n t of a l l new cars were o f f e r e d with four-wheel b r a k e s , by
1927 t h e y were s t a n d a r d equipment on 90 p e r c e n t of new cars. In 1924 only a t e n t h
of all t i r e production w a s of t h e low-pressure balloon design. By 1926 balloon and
traditional high-pressure t i r e s had about equal s h a r e s in t o t a l t i r e production. This
shows t h e r a p i d diffusion of two important automobile improvements throughout t h e
industry during t h e 1920s and, with a lag of a few y e a r s t o a d e c a d e , a l s o throughout
t h e automobile fleet. H e r e w e cannot analyze in d e t a i l a l l t h e c h a n g e s t h a t h a v e
been impiemented s i n c e t h e 1920s, but will r a t h e r consider t h o s e t h a t are
documented and c a n b e empirically assessed.
If w e neglect f o r t h e time being t h e r e c e n t use of e l e c t r o n i c s , most o t h e r
f e a t u r e s of t h e modern automobile (including aerodynamic styling) were introduced
soon a f t e r t h e r e p l a c e m e n t of animal-drawn vehicles. However, t h e introduction of
a new automobile component o r design c h a r a c t e r i s t i c usually p r e c e d e s by few
d e c a d e s t h e widespread adoption of t h i s innovation b y t h e whole industry. Thus,
many innovations t h a t were originally introduced d u r i n g t h e e a r l y d a y s of t h e
automobile did n o t diffuse t h r o u g h o u t t h e industry until t h e r e c e n t decades.
Figure 4.2 shows t h e substitution p r o c e s s of t h r e e major t y p e s of transmissions
in t h e United S t a t e s . The o l d e s t transmission, also used in some of t h e f i r s t vehicles,
i s t h e t h r e e - s p e e d manual g e a r box. In t h e United S t a t e s , t h e automatic
transmission w a s basically t h e only a l t e r n a t i v e to t h e t h r e e - s p e e d manual g e a r box,
mainly d u e t o t h e u s e of high t o r q u e and displacement engines. In E u r o p e , d u e to
d i f f e r e n t driving conditions a n d g e n e r a l l y smaller c a r s , four-speed g e a r boxes were
also common in t h e e a r l y d a y s of motor vehicles. Automatic transmission w a s in
many ways s u p e r i o r to manual a n d c e r t a i n l y o f f e r e d more convenience to t h e
a v e r a g e motorist by simplifying t h e o p e r a t i o n of t h e automobiie. The f i r s t designs
f o r a n automatic transmission a p p e a r e d in 1904 in t h e United S t a t e s and E u r o p e .
Frictional a n d c e n t r i f u g a l v a r i a n t s t u r n e d o u t not to b e viable a l t e r n a t i v e s and
definitely not competitive with manual transmissions.
Figure 4.2
Substitution in Production of Factory-Installed Transmissions.
Along with t h e s e less successful designs t h e f i r s t hydraulic automatic
transmissions with t o r q u e c o n v e r t e r s also a p p e a r e d . Torque c o n v e r t e r s a n d fluid
coupling designs were a d a p t e d to motor vehicles from similar German inventions of
t h e e a r l y 1900s f o r marine power a n d t o r q u e conversion systems. The f i r s t
automobiles with h y d r a u l i c automatic transmissions w e r e o f f e r e d in t h e United
S t a t e s in t h e late 1930s. In 1 9 3 7 Oldsmobiie o f f e r e d a semi-automatic transmission,
C h r y s l e r introduced "Fluid Drive" in 1938 a n d Oldsmobile "Hydra-Matic" in 1939, t h e
f i r s t fully automatic transmission with fluid coupling a n d a four-speed p l a n e t a r y
g e a r box. Thus, t h e l a t e 1 9 3 0 s mark t h e introduction of automatic transmissions as
a competitive a l t e r n a t i v e to t h e manual g e a r box.
The n e x t b r e a k t h r o u g h o c c u r r e d in 1942 when Buick introduced "Dynaflow", a n
automatic transmission utilizing a t o r q u e c o n v e r t e r . Soon a f t e r World War I1 o t h e r
m a n u f a c t u r e r s introduced similar automatic transmissions, although fluid coupling
w a s t h e typical design until t h e y were r e p l a c e d b y t o r q u e c o n v e r t e d transmissions.
By 1948, o n e t h i r d of all new cars had automatic transmissions, by 1 9 5 3 o n e half, a n d
by 1 9 6 3 t w o t h i r d s . Figure 4.2 shows t h i s r a p i d diffusion of t h e automatic
transmission in t h e United S t a t e s . By t h e late 1960s almost 9 0 p e r c e n t of new cars
w e r e equipped with a n automatic transmission a n d l e s s t h a n t e n p e r c e n t still h a d t h e
much c h e a p e r t h r e e - s p e e d g e a r box.
A t t h i s time t h e automatic w a s challenged from i t s position of dominance by t h e
introduction of t h e four-speed manual transmission a n d t h e l a t e r five-speed v a r i a n t
(in most cases basically a four-speed transmission with a n additional o v e r d r i v e
g e a r , t h e "sports" five-speed transmission being r e s t r i c t e d to a few highp e r f o r m a n c e c a r s ) . Thus, i t i s interesting to n o t e t h a t t h e t o r q u e c o n v e r t e d
automatics r e p l a c e d t h e l e s s efficient fluid coupling transmissions d u r i n g t h e s e
y e a r s as if to compensate f o r some of t h e efficiency advantage of t h e four- a n d
f ive-speed manual transmissions.
Higher fuel economy r e q u i r e m e n t s a n d t h e prolonged r e c e s s i o n of t h e l a s t
d e c a d e h a v e f a v o r e d t h e displacement of more expensive a n d l e s s efficient t h r e e s p e e d automatics, aithough more t h a n 8 0 p e r c e n t of new automobiies in t h e United
S t a t e s are s t i l l supplied with a n automatic transmission. Some of t h e s e new cars
a i r e a d y h a v e more efficient four-speed automatics; however, d u e to t h e lack of
a p p r o p r i a t e d a t a , i t i s n o t possible to analyze t h i s substitution p r o c e s s in i t s full
complexity by including t h r e e - , four-, a n d five-speed manual transmissions as w e l l as
t h r e e a n d four-speed automatics. Figure 4.2 shows t h a t automatics may i n c u r
additional losses to t h e four- a n d five-speed manual transmissions d u r i n g t h e n e x t
t w o d e c a d e s , shrinking t h e m a r k e t s h a r e of automatics in new cars to a b o u t 7 0
p e r c e n t , i.e. below t h e 1 9 5 5 level. This will p r o b a b l y not r e p r e s e n t t h e ultimate
state. of t h i s competition p r o c e s s . Instead, i t i s likely t h a t new designs will b e
introduced in t h e f u t u r e t h a t will in t u r n r e p l a c e t h e four- and five-speed manual
transmissionss.. T h e r e are a number of candidates, ranging from continuously
variable-ratio transmissions to e l e c t r i c conversion using b a t t e r i e s as intermediate
s t o r a g e in o r d e r to f l a t t e n t h e power requirements.
The continuously v a r i a b l e transmissions h a v e t h e additional a d v a n t a g e t h a t
t h e y o f f e r f a s t e r a c c e l e r a t i o n t h a n manual transmissions with t h e same vehicle
weight a n d engine performance. This means t h a t t h e y o f f e r t h e potential of
reducing fuel consumption with t h e same weight a n d a c c e l e r a t i o n p e r f o r m a n c e ,
b e c a u s e smaller engines c a n b e used. Since weight reduction i s usually v e r y costly
a n d aerodynamic improvements usually e a s i e r to implement, i t i s conceivable t h a t
t h e continuously v a r i a b l e transmission could o f f e r t h e solution to t w o conflicting
objectives, namely t o improve fuel efficiency with b e t t e r aerodynamics a n d smaller
engines without significant weight and a c c e l e r a t i o n reductions ( S e i f f e r t and Walzer,
1984). Thus, t h e continuously variable-ratio design a p p r o a c h e s t h e ideal
transmission performance, which i s basically t o allow t h e engine t o o p e r a t e in a
v e r y small i n t e r v a l with highest fuel efficiency, and b e s t power and t o r q u e
c h a r a c t e r i s t i c s . Actually, Ford and Fiat will b e introducing fully electronicallycontrolled variable-ratio
transmission i n t e g r a t e d with e l e c t r o n i c engine
management in l a t e 1986 on some Ford Fiesta and Fiat Uno models (Chilton's
Automotive Industries, 1985). However, transmissions should b e quiet, s a f e ,
efficient a n d reasonably p r i c e d s o t h a t a p r a c t i c a l design usually r e p r e s e n t s some
compromise between t h e ideal design requirements a n d t h e a c t u a l p r o d u c t
c h a r a c t e r i s t i c s . In view of t h e s e limitations, i t i s p r o b a b l e t h a t t h e next generation
of transmissions will c o n s t i t u t e a n evolutionary refinement and t h a t a revolutionary
solution, such as a continuously v a r i a b l e transmission, could b e introduced by most
manufacturers t h e r e a f t e r . An obvious candidate i s a hybrid design incorporating
t h e advantages of t h e o p e r a t i n g convenience of a n automatic with t h e efficiency of a
five-speed manual transmission. The f i r s t ' v e r s i o n s of such transmissions include
micro-processors as a replacement f o r t h e hydraulic mechanisms f o r t h e shift
operation. In addition, a micro-processor could also, in principle, r e p l a c e t h e
t o r q u e c o n v e r t e r and o p e r a t e a transmission d i r e c t l y by choosing optimai shift
i n t e r v a l s and engine o p e r a t i n g conditions. Thus, a n algorithm could c o n t r o l
everything from t h e engine t o t h e wheels (including b r a k e s ) and t h e d r i v e r would
indicate t h e c o n t r o l s by two pedals ( a c c e i e r a t o r and b r a k e ) like in a n automobiie
with a n automatic transmission. Some manufacturers a l r e a a y o f f e r similar but
simpler micro-processor controlled automatic transmissions. Assuming t h a t o n e
p e r c e n t of all new cars were o f f e r e d with such advanced automatic transmission by
1990, o n e could s p e c u l a t e on t h e basis of t h e substitution dynamics shown in Figure
4.2 t h a t i t could t a k e up t o t h r e e d e c a d e s b e f o r e such a new transmission t y p e would
b e installed in o n e half of a l l new cars. Another way of describing t h e s e
technological changes i s t h a t t h e manual clutch w a s r e p l a c e d by hydraulic
mechanism in t h e p a s t and t h a t both will be r e p l a c e d by electronically-controlled
systems in t h e f u t u r e .
Figure 4.2 i l l u s t r a t e s t h a t t h e market substitrtion of d i f f e r e n t transmission
t y p e s i s as r e g u l a r as f o r o t h e r technological changes. The interesting element
h e r e i s t h a t t h i s technological substitution p r o c e s s c a n be s e e n as t h e competition
of a given t y p e of automobile component f o r t h e s h a r e of new cars. An a b s t r a c t i o n
of t h i s substitution p r o c e s s implies t h a t a l l new c a r s constitute t h e environment o r
"ecosystem" f o r d i f f e r e n t t y p e s of transmissions, and t h a t within t h i s environment
t h e y s t r u g g l e f o r dominance o r survival in d i f f e r e n t "eco-niches". This i s in many
ways equivalent t o t h e competition in some biological environments. For example,
Marchetti (1982) h a s d e s c r i b e d a similar competition p r o c e s s between d i f f e r e n t
human diseases f o r "shares" of sick people.
Disc b r a k e s are a n o t h e r example of a n automobile component t h a t w a s a l r e a d y
in use on some cars in t h e e a r l y 1900s, b u t did not r e p l a c e conventional drum
b r a k e s until half a c e n t u r y l a t e r . Another similarity t o t h e automatic transmission
i s t h a t , although both disc b r a k e s and automatics a p p e a r e d on some d a r i n g
automobile designs in t h e e a r l y 1900s, t h e y did not r e p l a c e t h e drum b r a k e and t h e
three-speed manual transmission until t h e final design w a s developed f o r a n o t h e r
p u r p o s e and applied t o t h e automobile. The hydraulic torque-converted automatic
transmission was invented f o r marine engines and t h e c a l i p e r disc b r a k e w a s used in
t h e a i r c r a f t industry during t h e 1940s. Ilowever, while diffusion of t h e automatic
transmission s t a r t e d soon a f t e r World War I1 in t h e American automobile industry,
t h e disc b r a k e w a s a l a t e starter in t h e United S t a t e s . Thus, diffusion of t h e
automatic transmission had a definite lead in t h e United S t a t e s compared t o E u r o p e ,
but d i s c b r a k e s became s t a n d a r d equipment on European cars long b e f o r e they were
common in America. Once t h e replacement of drum by disc b r a k e s on t h e f r o n t
wheels w a s initiated in t h e 1960s, a complete switch o v e r w a s accomplished within a
decade. Figure 4.3 shows t h a t soon a f t e r t h e S t u d e b a k e r Avanti w a s o f f e r e d as t h e
f i r s t American automobile with s t a n d a r d disc b r a k e s in 1963, most o t h e r
manufacturers followed and t h a t by 1970 half of all new American automobiles were
equipped with front-wheel disc b r a k e s . A d e c a d e l a t e r t h e y were s t a n d a r d on more
t h a n 90 p e r c e n t of new c a r s .
Figure 4.3
Substitution in Production of Drum and Disc Brakes.
Figure 4.4 shows t h e diffusion p r o c e s s of a i r conditioning as factory-installed
equipment in new American cars. After-market installments are not included and a l l
v a r i a n t s of climate c o n t r o l equipment are grouped t o g e t h e r , including automatic a n d
manual a i r conditioning. Although a i r conditioning i s qualitatively a d i f f e r e n t kind
of automobile component t h a n transmission o r b r a k e s , s i n c e i t d o e s not d i r e c t l y
s e r v e a function n e c e s s a r y f o r o p e r a t i n g t h e vehicle, i t i s a v e r y important f a c t o r
in contributing t o comfort. While a i r conditioning i s not such a n important
automobile component in E u r o p e compared with t h e United S t a t e s , o t h e r f a c t o r y installed, "comfort" options, such as t h e sliding sun roof o r sport-seats, may h a v e
comparable importance t o t h a t of a i r conditioning in America. Figure 4.4 shows t h a t
t h e introduction of a i r conditioning in new automobiles p o r t r a y s basically t h e same
dynamics as t h e diffusion of t h e o t h e r automobile components analyzed s o f a r transmissions a n d b r a k e s .
f r a c t lon ( f )
PAI-f)
Figure' 4.4
Diffusion of Factory-Installed Air Conditioning.
Figure 4.5 shows t h e substitution of diagonal by r a d i a l t i r e s as factory-installed
equipment on new American cars. The introduction of r a d i a l t i r e s by American
manufacturers i s analogous t o t h e dynamics of disc b r a k e diffusion. Both
components, as factory-installed equipment, were l a t e starters in t h e United S t a t e s
compared with E u r o p e , were introduced as s t a n d a r d equipment at a b o u t t h e same
time, and r e p l a c e d t h e i r p r e d e c e s s o r s in o n e half of new c a r s within o n e decade.
Unfortunately, Figure 4.5 does n o t tell t h e whole s t o r y about t h e diffusion of r a d i a l
t i r e s , s i n c e m a n u f a c t u r e r s did not r e p o r t r a d i a l t i r e installment b e f o r e t h e 1 9 7 3
model y e a r . I t i s likely t h a t t h i s may account f o r t h e relatively p o o r description of
t h e substitution p r o c e s s by t h e logistic c u r v e (compared with o t h e r examples).
The l a s t example of technological change at t h e level of factory-installed
equipment i s t h e c a s e of power s t e e r i n g . Figure 4.6 shows t h a t during t h e 1950s
more t h a n t e n p e r c e n t of all new American c a r s were delivered with power s t e e r i n g ,
but t h a t t h e 90 p e r c e n t m a r k e t s h a r e o c c u r r e d in t h e l a t e 1970s, more t h a n two
d e c a d e s l a t e r . Thus, w e have o b s e r v e d t h a t t h e diffusions of disc b r a k e s and r a d i a l
t i r e s were similar with r e s p e c t t o t h e i r initial introduction and t h e substitution
rate. Both of t h e s e substitutions improved t h e p e r f o r m a n c e and s a f e t y of t h e
vehicles. Air conditioning a n d power s t e e r i n g , on t h e o t h e r hand, primarily
improved t h e comfort of o p e r a t i n g a n automobile and are t h u s more a function of
consumer c h o i c e t h a n technical performance, although in some c a s e s t h e consumer
d o e s not h a v e a real choice s i n c e some c a r s have power s t e e r i n g and automatic
transmission as s t a n d a r d factory-installed equipment. In any case, t h e s e f o u r
f/( 1-f)
Figure 4.5
fraction (f)
Substitution of Factory-Installed Diagonal and Radial Tires.
examples indicate t h a t technological r a t h e r t h a n comfort improvements o c c u r
f a s t e r in t h e automobile industry, although i t i s c l e a r l y dangerous t o generalize on
t h e basis of such a small sample. Nevertheless, i t i s curious t o note t h a t t h e
substitution of t h e t h r e e - s p e e d manual by automatic transmission c a n b e placed
somewhere between t h e s e two g r o u p s of factory-installed equipment with r e s p e c t t o
t h e duration of t h e substitution p r o c e s s , s i n c e automatic transmission a f f e c t s , t o
some e x t e n t , both t h e comfort a n d technical performance.
Figure 4.6
Substitution in Production of Manual and Power S t e e r i n g .
5 AUTOMOBILES AND EMISSIONS
Most of t h e technological c h a n g e s d e s c r i b e d up to now s e r v e d to improve some
a s p e c t of automobile production o r p e r f o r m a n c e . A s s u c h new technologies were in
some s e n s e s u p e r i o r to t h o s e t h e y r e p l a c e d , b u t t h e y generally a l s o had some
disadvantages. The most common drawback of new technologies i s t h a t t h e y are
usually more expensive t h a n t h e o l d e r ones. However, new technologies may a l s o b e
a n a t t r a c t i v e s o u r c e of p r o f i t s in d a y s of low unit p r o f i t s , especially during p h a s e s
of intensive competition a n d m a r k e t s a t u r a t i o n .
F o r example, automatic
transmission, disc b r a k e s , r a d i a l t i r e s , a n d power s t e e r i n g are all more costly t h a n
t h e equipment t h e y r e p l a c e d . In t h i s s e n s e , emission c o n t r o l o r r e d u c t i o n equipment
c a n also b e viewed as a technological change. I t improves some c h a r a c t e r i s t i c s of
t h e vehicle - in t h i s c a s e by r e d u c i n g t h e emissions b u t i t i s a l s o associated with
disadvantages, such as h i g h e r cost. Today, almost a l l p a s s e n g e r vehicles h a v e some
equipment t h a t h e l p s r e d u c e emissions. To some e x t e n t , emission r e d u c t i o n s were
originally a "by-product" of o t h e r technological improvements of vehicles. F o r
exampie, fuel-injected engines, especially in conjunction with advanced combustion
c h a m b e r designs, are more fuel efficient a n d h a v e h i g h e r p e r f o r m a n a e t h a n t h e
equivaient c a r b u r e t e d engines. A t t h e same time, t h e y also c a n substantially lower
h y d r o c a r b o n a n d c a r b o n monoxide emissions. O t h e r emission c o n t r o l measures c a n
b e considered as m e r e add-ons t h a t d o not r e q u i r e substantial c h a n g e s to t h e rest of
t h e vehicle. One example of s u c h a measure i s t h e c r a n k c a s e emissions c o n t r o l .
-
By c o n t r a s t , vehicles with c a t a l y t i c c o n v e r t e r s r e q u i r e c h a n g e s in t h e engine,
fuel, a n d e x h a u s t systems. These cars are considerably more expensive t h a n
equivalent models without c a t a l y t i c c o n v e r t e r s a n d a l s o h a v e lower fuel efficiency,
although i t i s p r o b a b l y t r u e t h a t vehicles with c o n v e r t e r s a c h i e v e g r e a t e r fuel
efficiency t h a n vehicles with o t h e r c o n t r o l methods meeting t h e same s t a n d a r d s .
However, p e r h a p s t h e most important d i f f e r e n c e between cars with c a t a l y s t a n d
t h o s e with o t h e r emission c o n t r o l s i s t h a t c a t a l y t i c c o n v e r t e r s n e c e s s i t a t e t h e u s e
of lead-free gasoline. Thus, t h e use of c a t a l y t i c c o n v e r t e r s r e q u i r e s t h e
modification of t h e i n f r a s t r u c t u r e f o r production and distribution of motor fuels. In
t h i s s e n s e t h e introduction of lead-free c a r s i s comparable to t h e introduction of
diesel a n d o t h e r vehicles powered b y a l t e r n a t i v e fuels, although most of t h e o l d e r
cars c a n u s e unleaded gasoline, which i s n o t n e c e s s a r i l y t h e c a s e with a l t e r r a t i v e
f u e l s such as diesel o r methanol. Figure 5 . 1 shows t h e diffusion of emission c o n t r o l s
in t h e American automobile f l e e t , s e e n as t h e substitution p r o c e s s of t h r e e b r o a d
c a t e g o r i e s of vehicles. The oldest kind of automobile i s without a n y explicit
emission controls. F i g u r e 5.1 shows t h a t by 1967 only half of t h e automobiles in t h e
United S t a t e s h a d no emission c o n t r o l s whatsoever. S t a r t i n g in 1 9 6 5 c r a n k c a s e
c o n t r o l s were mandatory on a l l new vehicles in o r d e r to r e d u c e h y d r o c a r b o n
emissions. With t h e 1 9 6 8 model e x h a u s t c o n t r o l s were r e q u i r e d in o r d e r to r e d u c e
c a r b o n monoxide a n d h y d r o c a r b o n emissions. Finally, in 1 9 7 1 fuel e v a p o r a t i o n
c o n t r o l s to eliminate losses from gasoline t a n k s a n d c a r b u r e t o r s were r e q u i r e d on
all new c a r s . Although all of t h e s e emission c o n t r o l s a r e grouped t o g e t h e r u n d e r
o n e single c a t e g o r y in F i g u r e 5.1, i t i s obvious t h a t t h i s includes a whole h o s t of
d i f f e r e n t technological changes. C a r s with some o r all of t h e s e emission c o n t r o l s
slowly r e p i a c e d t h o s e with none. By 1975 almost 9 0 p e r c e n t of all cars r e g i s t e r e d in
t h e United S t a t e s had some o r all of t h e s e emission c o n t r o l s and c a r s without a n y
c o n t r o l s were r e d u c e d to a b a r e f o u r p e r c e n t of t h e f l e e t .
fraction ( f )
Figure 5.1
Substitution of C a r s with Emission Controls.
S t a r t i n g in 1 9 7 1 some models o f f e r e d n i t r o u s oxide r e d u c t i o n measures and by
1 9 7 3 lower nitrogen oxides emissions were r e q u i r e d o n a l l new c a r s . In 1975
c a t a l y t i c c o n v e r t e r s were mandatory t.o meet more s t r i n g e n t h y d r o c a r b o n , c a r b o n
monoxide, and nitrogen oxides emission s t a n d a r d s . By 1980, half of a l l automobiles
had such advanced emission r e d u c t i o n c o n t r o l s a n d , a c c o r d i n g to Figure 5.1, i t c a n
b e e x p e c t e d t h a t by 1990 s u c h emission c o n t r o l s will b e almost universal. Thus, f o r
t h e United S t a t e s i t c a n b e conciuded t h a t t h e diffusion of automobiles with c a t a l y t i c
c o n v e r t e r s i s a r e l a t i v e l y long, although r e g u l a r , p r o c e s s with a d u r a t i o n of a b o u t
t w o decades. In o t h e r words, i t took a d e c a d e from introduction to 5 0 p e r c e n t
p e n e t r a t i o n f o r both automobiles with emission c o n t r o l s and l a t e r f o r automobiles
with c a t a l y t i c c o n v e r t e r s . If t h i s time c o n s t a n t w a s a p p l i c a b l e in E u r o p e , i t c a n b e
e x p e c t e d t h a t from t h e introduction d a t e of c a t a l y t i c c o n v e r t e r s at l e a s t two
decades will b e r e q u i r e d f o r t h e i r complete diffusion.
This example of t h e diffusion of emission c o n t r o l s in American automobiles a n d
t h e e a r l i e r example of t h e replacement of h o r s e s (and mules) by automobiles
d e s c r i b e t w o substitution p r o c e s s e s at t h e level of t h e f l e e t ( o r population), while
all t h e o t h e r examples of technological c h a n g e s in automobile production and
vehicle components i l l u s t r a t e d substitution p r o c e s s e s in t e r m s of production ( o r
f a c t o r y sales). In t h e c a s e of replacement of h o r s e s a n d animal-drawn vehicles by
automobiles, t h e substitution p r o c e s s w a s a l s o d e s c r i b e d in t e r m s of production. I t
w a s shown t h a t t h e c h a n g e s at t h e level of t h e whole f l e e t lagged behind equivalent
changes, in t e r m s of production, by a b o u t six y e a r s . W e h a v e concluded t h a t t h i s l a g
i s l a r g e l y d u e to t h e a g e s t r u c t u r e of t h e vehicle f l e e t s and t h a t i t c o r r e s p o n d s to
t h e a v e r a g e a g e of a b o u t six y e a r s f o r all vehicles. Thus, a distinction always e x i s t s
between t h e market s h a r e s of a new and a n old technology a s measured by
production r a t e s and t h e market s h a r e s as measured by f l e e t composition, provided
t h a t a period of obsolescence e x i s t s f o r t h e embodiment of t h e old technology. The
lag between t h e two substitution p r o c e s s e s is usually a good p r o x y f o r t h e a v e r a g e
a g e of t h e f l e e t , but i t i s not a good indicator f o r t h e a v e r a g e life s p a n , especially in
cases of r a p i d f l e e t growth r a t e s .
Fisher (1985) o b s e r v e d t h a t t h e introduction of emission c o n t r o l s into t h e
American automobile f l e e t , given in Figure 5.1, i l l u s t r a t e s v e r y vividly t h e
d i f f e r e n c e between t h e m a r k e t s h a r e s of a new and a n old technology as measured
by production ( o r s a l e s ) r a t e s and by f l e e t composition, b e c a u s e t h e emission
c o n t r o l s were mandated by law as of a specific d a t e . The p r o p o r t i o n of new
automobiles incorporating emission c o n t r o l s as a function of time r i s e s rapidly from
n e a r z e r o p r i o r t o t h e legally mandated d a t e t o n e a r 100 p e r c e n t just a f t e r , while
t h e logistic substitution t a k e s a b o u t ten y e a r s from o n e p e r c e n t of t h e f l e e t until
o n e half of t h e automobiles are r e p l a c e d (Fi'gure 5.1). H e r e t h e time constant of t h e
logistic c u r v e is not r e l a t e d t o competition ,between t h e new and t h e old
technologies, b e c a u s e replacement in t e r m s of new cars w a s almost instantaneous.
The substitution depends on t h e rate of obsolescence of old automobiles without
emission c o n t r o l s and t h e i r replacement by new o n e s with c o n t r o l s and on t h e growth
of t h e whole f l e e t in addition t o t h e replacement level. Actually, t h e a v e r a g e a g e of
automobiles in use in t h e United S t a t e s h a s v a r i e d considerably during t h e l a s t 45
years.
The l a s t decline in t h e a v e r a g e a g e during t h e l a t e 1960s and t h e
subsequent i n c r e a s e could b e a n explanation f o r t h e somewhat more r a p i d d e c r e a s e
of market s h a r e s of automobiles without any emission c o n t r o l s t h a n t h e logistic
t r e n d line until 1969 (Figure 5.1) and f o r t h e somewhat slower d e c r e a s e t h e r e a f t e r .
Each p h a s e of d e c r e a s i n g a v e r a g e a g e was accompanied by a more r a p i d growth of
t h e whole f l e e t and e a c h p h a s e of prolongation of a v e r a g e a g e by a slower growth
(see Figure 3.1). Thus, t h e a c t u a l life expectancy of automobiles is difficult t o
a s s e s s , s i n c e fluctuations of t h e f l e e t growth rate a p p e a r t o b e a n important f a c t o r
in determining t h e a v e r a g e a g e of t h e fleet. Unfortunately, explicit s t a t i s t i c s on t h e
survival r a t e of automobiles by model y e a r a n d t y p e o v e r l o n g e r periods are
generally lacking. A good approximation f o r t h e life span of automobiles in t h e
United S t a t e s i s about t e n y e a r s . Marchetti (1983) showed t h a t t h e s u r v i v o r s c u r v e
f o r t h e 1967 "cohort" of American automobiles a p p e a r s t o follow a logistic t r e n d
with o n e half of t h e vehicles surviving 9.2 y e a r s . Nevertheless, it is possible t h a t
t h e life e x p e c t a n c y of automobiles changed in t h e p a s t , converging toward t e n y e a r s
during t h e l a s t two decades. A b e t t e r understanding of t h e "demographic" a s p e c t s
of t h e a g e s t r u c t u r e a n d mortality rates t o g e t h e r with t h e growth rates of t h e whole
f l e e t would b e v e r y useful in determining t h e duration of f u t u r e technological
changes, o n c e a substitution p r o c e s s h a s been initiated in new cars.
The f a c t t h a t automobiles with c a t a l y t i c c o n v e r t e r s must b e fueled with leadf r e e gasoline in o r d e r t o avoid c a t a l y s t damage c a n b e used as verification f o r t h e
a c c u r a c y of t h e projection and substitution dynamics of emission c o n t r o l s in
automobiles. Figure 5.2 shows t h e substitution of leaded by lead-free gasoline in t h e
United S t a t e s . I t is r e a s s u r i n g t h a t t h e 5 0 p e r c e n t substitution mark in 1980
c o r r e s p o n d s e x a c t l y t o t h e same penetration level of cars with a cataiyst.
Nevertheless, unleaded gasoline r e p l a c e s t h e leaded v a r i a n t somewhat slower t h a n
-
-
-
-
-
3 The average age of t h e f l e e t increased from 5.5 y e a r s in 1941 t o 9 y e a r s by t h e end of the war and
decreased again t o 5.5 y e a r s by 1958, then ft r o s e s l i g h t l y t o 6 y e a r s during t h e early 1960s and
decreased again t o 5.55 y e a r s by 1970, and finally i t r o s e again t o 7.81 y e a r s by 1982 (Automobile
F a c t s and Figures, 1971; and U. S. Department of Commerce, 1984).
-
-
-
fraction (f)
Figure 5.2
Substitution of Leaded by Lead-Free Gasoline.
catalyst-equipped c a r s r e p l a c e o t h e r ones. This somewhat slower diffusion could b e
d u e t o t h e f a c t t h a t new c a r s are more fuel efficient t h a n t h e old ones (although
t h e y may b e d r i v e n more) and a l s o d u e t o t h e p r a c t i c e of some owners of automobiles
with c a t a l y t i c c o n v e r t e r s t o u s e leaded gasoline d u e t o lower c o s t , in s p i t e of
d e t r i r e n t a l environmental consequences - such vehicles pollute more t h a n d o
efficient automobiles without a catalyst. In f a c t , up t o 40 p e r c e n t of a l l automobiles
with c o n v e r t e r equipment in t h e United S t a t e s are claimed t o h a v e a defective
c a t a l y s t , usually d u e t o t h e u s e of leaded gasoline ( F r a n k f i r t e r ALLgemeine
Z e i t u n g , 1985). If t h i s t r e n d should continue, i t could b e e x p e c t e d t h a t t h e
p r o j e c t e d i n c r e a s e in m a r k e t s h a r e of unleaded gasoline may b e overestimated in
Figure 5.2.
6 A U T O M O B U S AND THE TRANSPORT SYSTEM
The examples given above indicate t h a t i t is possible t o consistently d e s c r i b e
t h e evolution of motor vehicles in t h e United S t a t e s as a s e r i e s of technological
substitution p r o c e s s e s . F i r s t , t h e automobile r e p l a c e d t h e h o r s e and t h e c a r r i a g e
and t h e n new g e n e r a t i o n e s of motor vehicles r e p l a c e d old ones. Through t h i s
replacement p r o c e s s t h e automobile f l e e t itself underwent fundamental changes with
r e s p e c t t o t h e c h a r a c t e r i s t i c s and s t r u c t u r e of t h e vehicles. New technologies were
introduced and t h e i r s h a r e s in new cars i n c r e a s e d , in g e n e r a l aiong a logistic
growth p a t h , but with d i f f e r e n t rates. Substitution of old technologies r a n g e d
between almost instantaneous t a k e o v e r , as mandated by t h e law f o r c a t a l y t i c
c o n v e r t e r s , t o between o n e t o t h r e e decades until new technologies and automobile
equipment were embodied in o n e half of t h e new cars. The corresponding diffusion
throughout t h e f l e e t lagged by about five t o t e n y e a r s , in a c c o r d a n c e with t h e
changing a g e s t r u c t u r e of t h e vehicles in use w a s , at l e a s t in t h e p a s t , largely due t o
t h e short-term fluctuations in t h e growth rates of t h e whole f l e e t . However, t h e
long-term growth of t h e vehicle f l e e t followed a r a t h e r s t a b l e s e c u l a r t r e n d once
animal-drawn vehicles were r e p l a c e d (see Figures 3.1 and 3.4). This long-term
growth t r e n d d e s c r i b e s t h e expansion of r o a d vehicles in g e n e r a l ; and p a r a l l e l s t h e
growth of s u r f a c e d r o a d s mileage since t h e 1930s (see Figure 3.3). In a b r o a d e r
c o n t e x t t h e expansion of r o a d vehicles as a p a r t of t h e o v e r a l l t r a n s p o r t system
must b e compared with t h e development of o t h e r competing t r a n s p o r t modes.
Obvious competitors are p a s s e n g e r t r a i n s , buses, airlines, subways, a n d o t h e r forms
of u r b a n t r a n s p o r t . S h i p s h a v e been r e d u c e d t o a small f r a c t i o n of t o t a l p a s s e n g e r
t r a f f i c s o t h a t t h e y need not b e considered as a viable a l t e r n a t i v e t o t h e automobile.
By excluding u r b a n a n d metropolitan t r a n s p o r t because explicit s t a t i s t i c s are
generally lacking, t h e competition f o r i n t e r c i t y p a s s e n g e r t r a f f i c i s reduced t o f o u r
significant t r a n s p o r t modes. Figure 6.1 shows t h e substitution of railways, buses,
cars, a n d airways as long-distance t r a v e l a l t e r n a t i v e s in t h e United S t a t e s . The
s h a r e s of e a c h mode of t r a n s p o r t are calculated in t e r m s of passenger-miles
t r a v e l e d in a given y e a r . According t o t h e market substitution analysis in Figure
6.1, t h e p a s s e n g e r c a r i s still t h e main choice f o r t h e majority of Americans a n d will
remain dominantly s o well into t h e next c e n t u r y . The l o s e r s are t h e railways and
buses.
During t h e l a s t c e n t u r y animal-drawn vehicles and railways were t h e two
principal modes of long-distance t r a v e l with t h e exception of p a s s e n g e r ships.
However, s h i p s provided connections between v e r y few c i t i e s in t h e United S t a t e s .
After successfully replacing t h e horse-drawn c a r r i a g e , t h e automobile proceeded t o
compete with t h e railways. Figure 6.1 does not indicate t h e full drama of t h i s
replacement p r o c e s s because d a t a are available only f o r t h e period a f t e r 1950.
During t h e 1930s t h e automobile became t h e dominant form of r o a d t r a n s p o r t and, as
Figure 6 . 1 shows, only 20 y e a r s l a t e r a l s o t h e dominant and almost exclusive form of
i n t e r c i t y t r a v e l . Buses were t h e latecomers in t h e United S t a t e s and a f t e r t h e y had
a c q u i r e d a few p e r c e n t of t h e t r a f f i c t h e y a p p e a r e d t o b e l e f t with t h e residual of
t h e market. Their s h a r e did n o t decline as rapidly as t h a t of t h e by now almost
e x t i n c t p a s s e n g e r r a i l r o a d s , but according t o Figure 6.1 t h e y will a l s o b e reduced t o
l e s s t h a n a one-percent s h a r e by t h e 1990s. Airplanes are t h e shining stars in t h e
competition f o r long-distance t r a v e l . During t h e n e x t two d e c a d e s t h i s t r e n d will
expand t h e s h a r e of airways in i n t e r c i t y t r a v e l t o almost 40 p e r c e n t , reducing t h e
automobiles t o little more t h a n 60 p e r c e n t and virtually eliminating railways and
buses. Thus, automobiles will remain t h e most important, although declining, form of
long-distance t r a v e l throughout t h i s c e n t u r y in t h e United S t a t e s , while a i r c r a f t will
f r a c t i o n (PI
lo-'
Figure 6.1
I n t e r c i t y P a s s e n g e r Traffic Substitution.
continue t h e i r r a p i d expansion by increasing t h e m a r k e t s h a r e s t h e y c u r r e n t l y
control.
7 CONCLUSIONS
The expansion and evolution of t h e automobile in t h e United S t a t e s e m e r g e s as a
r e g u l a r p r o c e s s when s e e n t h r o u g h t h e paradigm of technological substitution. A t
t h e highest level of a b s t r a c t i o n t h e automobile itself diffused within t h e c o n t e x t of a
b r o a d e r substitution p r o c e s s . The replacement of h o r s e s a n d animal-drawn r o a d
vehicles by antomobiles w a s completed by 1930 and from t h e n on t h e expansion of
t h e automobile f l e e t followed t h e same s e c u l a r t r e n d as did t h e horse-drawn vehicles
e a r l i e r . Thus, t h e growth of s u r f a c e d mileage and r o a d vehicles, animal-drawn a n d
motor powered, a p p e a r s as t h e expansion of t h e same t r a n s p o r t a t i o n s e r v i c e t h a t
evolved o v e r time as i t s h i f t e d to t h e h o r s e i e s s c a r r i a g e . Concurrently, r o a d
vehicles themselves competed with o t h e r modes of t r a n s p o r t a t i o n , as w a s i l l u s t r a t e d
in t h e case of i n t e r c i t y p a s s e n g e r t r a n s p o r t . The dynamics of t h i s substitution
p r o c e s s indicate t h a t t h e automobile will r e t a i n i t s p l a c e of dominance throughout
t h e c e n t u r y , although i t s position f o r long-distance t r a v e l i n g i s slowly being e r o d e d
by t h e a i r p l a n e .
Thus, t h e expansion a n d use of t h e automobile e m e r g e s as a. s e r i e s of
substitution p r o c e s s e s from o l d e r t o newer modes of t r a n s p o r t a t i o n . However, t h e
automobile itself developed and evolved t h r o u g h many i n t e r l a c e d technological
c h a n g e s t h a t profoundly improved t h e production p r o c e s s a n d t h e vehicles
themselves. These technological c h a n g e s are also d e s c r i b e d as substitution
p r o c e s s e s . The c h a n g e s in t h e production methods a n d t h e components of t h e
vehicles are much m o r e dynamic and on a f a s t e r time-scale t h a n t h e substitution
p r o c e s s e s in t h e o v e r a l l t r a n s p o r t a t i o n o r e n e r g y system t h a t l a s t e d up to 8 0 y e a r s
from t h e introduction d a t e to t h e p e r i o d when o n e half of t h e o l d e r technology was
r e p l a c e d . Sometimes, new automobile components o r production methods were
introduced almost instantaneously, b u t more o f t e n t h e p r o c e s s l a s t e d 1 0 to 3 0 y e a r s
b e f o r e t h e new technology was embodied in o n e half of new c a r s .
The c o r r e s p o n d i n g dissemination of t h e new automotive technologies throughout
t h e f l e e t s Lasted up to a d e c a d e l o n g e r , spanning from t h e time of introduction a few
a u t o z o b i l e generations. F o r obvious r e a s o n s such c h a n g e s cannot diffuse within a
s h o r t e r time i n t e r v a l t h a n t h e s p a n of a single automobile generation. Thus, t h e s e
substitution p r o c e s s e s c a n b e c h a r a c t e r i z e d as dynamic s i n c e t h c y o c c u r almost as
f a s t as t h e model changes. This i l l u s t r a t e s t h e point t h a t t h e volatile n a t u r e of t h e
automotive industry i s l a r g e l y d u e to r a p i d c h a n g e s in production p r o c e s s e s a n d
consumer demands - usually less t h a n two d e c a d e s are available f o r fundamental
c h a n g e s (Casti a n d Nakicenovic, 1983). T h e r e f o r e , we c a n e x p e c t t h a t a r o u n d t h e
y e a r 2000, almost all c a r s will h a v e as s t a n d a r d equipment some of t h e successful
innovations introduced d u r i n g t h e last t e n y e a r s , such a s electronically controlled
b r a k e s (anti-skid), f u e l a n d ignition system, suspension, a n d p e r h a p s also
transmission (indication of optimal s h i f t times f o r manual versions, a n d full c o n t r o l
f o r automatics), on-board c a l c u l a t o r a n d diagnostic system, t u r b o c h a r g i n g a n d / o r
four-valve engine, a n d a h i g h e r s h a r e of light weight m a t e r i a l s , s u c h as composites,
plastics, alloys, a n d ceramics, to name just a few f e a t u r e s a l r e a d y available in some
automobiles.
During t h e same p e r i o d a b o u t o n e half of t h e f l e e t could also i n c o r p o r a t e
a d v a n c e s t h a t a r e being developed today b u t not y e t p e r f e c t e d , s u c h as a g a s
t u r b i n e or a h y b r i d propulsion system with a n internal-combustion engine, e l e c t r i c
g e n e r a t o r , a n d motor with o r without s t o r a g e , continuously v a r i a b l e transmission,
e l e c t r o n i c guidance and information system, and p e r h a p s also a fully automated
vehicle with autopilot and navigation system. Some of t h e s e a d v a n c e s seem v e r y
likely today and will c e r t a i n l y b e soon available on s p e c i a l t y automobiles; some are
a l r e a d y i n c o r p o r a t e d in experimental c a r s , utility, and military vehicles (such as
t h e hybrid diesel-electric propulsion, variable-ratio transmission and gas t u r b i n e ) ;
o t h e r are more speculativeand may n e v e r b e introduced.
A g e n e r a l conclusion i s t h a t changes in t h e c h a r a c t e r i s t i c s of t h e automobile
itself and i t s production p r o c e s s o p e r a t e o v e r a period of a f e w d e c a d e s , while
c h a n g e s in t h e t r a n s p o r t system of which motor vehicles are b u t a p a r t r e q u i r e
much l o n g e r , spanning almost 80 y e a r s b e f o r e o n e half of t h e old technologies or
i n f r a s t r u c t u r e are r e p l a c e d . Thus, t h e automobile will remain t h e dominant form of
p e r s o n a l t r a n s p o r t t h r o u g h o u t t h i s c e n t u r y , but c o n c u r r e n t r a p i d changes will
a f f e c t both vehicle production and design, implying t h a t t h e r e will b e l o s e r s and
winners in t h e industry, depending on who s e l e c t s t h e "right" c h a n g e s f o r t h e
evolving markets.
DATA SOURCES
Primary E n e r g y C o n s u m p t i o n
All p r i m a r y e n e r g y consumption s e r i e s w e r e c o n v e r t e d from original units into
GWyr/yr.
C o n s u m p t i o n of Commercial P r i m a r y E n e r g y Sources:
E n e r g y consumption i s given in GWyr/yr. Fuel wood consumption is from Putnam
(1953) for t h e period 1 8 0 0 to 1849 and from t h e U. S . Department of Commerce
(1970) for t h e p e r i o d 1 8 5 0 to 1970. Both time s e r i e s a r e based on t h e
r e c o n s t r u c t i o n of fuel wood use in t h e United S t a t e s in Reynolds and P i e r s o n (1942)
and F o r e s t S e r v i c e R e p o r t (1946). Putnam's s e r i e s w a s a d j u s t e d t o t h e same
conversion from physical t o e n e r g y units as in t h e U. S. Department of Commerce
(1970).
Consumption of bituminous, a n t h r a c i t e , a n d t o t a l coal are from Putnam (1953)
f o r t h e period 1800 to 1899, from S h u r r and N e t s c h e r t (1960) a n d t h e U. S.
Department of Commerce (1970) f o r t h e p e r i o d 1950 to 1970, from t h e U. S .
Department of E n e r g y (1980) for t h e period 1 9 7 1 t o 1978, a n d from t h e U. S .
Department of E n e r g y (1982) f o r t h e period 1 9 7 9 to 1982.
Crude oil a n d n a t u r a l g a s consumption i s from Putnam (1953) f o r t h e p e r i o d
1850 to 1899, from t h e U. S. Department of Commerce (1970) f o r t h e p e r i o d 1900 to
1965, from t h e U. S . Department of E n e r g y (1980) f o r t h e period 1966 t o 1978, and
from t h e U. S. Department of E n e r g y (1982) f o r t h e p e r i o d 1979 to 1982.
D i r e c t (mechanical) water power use i s from Putnam (1953).
Hydropower i s from t h e U. S . Department of Commerce (1970) f o r t h e p e r i o d
1885 to 1965, from t h e U. S. Department of Energy (1980) f o r t h e p e r i o d 1966 t o
1978, a n d from t h e U. S . Department of E n e r g y (1982) for t h e p e r i o d 1 9 7 9 t o 1982.
Hydro-electricity consumption w a s calculated as both fossil e n e r g y equivalent a n d
as d i r e c t e l e c t r i c i t y inputs.
Nuclear e n e r g y consumption is from t h e U. S . Department of E n e r g y (1980) f o r
t h e p e r i o d 1960 to 1 9 7 8 a n d from t h e U. S . Department of E n e r g y (1982) f o r t h e
period 1979 to 1982.
C o n s u m p t i o n of ALL P r i m a r y E n e r g y Sources:
Consumption of fuel wood, d r a f t animal f e e d , d i r e c t (mechanical) wind a n d water
power, hydropower, coal, oil, n a t u r a l g a s , a n d n u c l e a r e n e r g y was t a k e n from Fisher
(1974) f o r t h e p e r i o d 1 8 5 0 to 1 9 5 0 in five-year i n t e r v a l s and annually from 1950 to
1970. W e h a v e extended t h e time s e r i e s of commercial e n e r g y s o u r c e s (coal, oil,
n a t u r a l g a s , hydropower, a n d n u c l e a r e n e r g y ) from 1970 to 1982 from t h e
consumption s e r i e s given a b o v e (Consumption of Commercial P r i m a r y E n e r g y
Sources). Hydropower i s given as both fossil e n e r g y equivalent a n d as d i r e c t
e l e c t r i c i t y inputs. D i r e c t wind a n d water power i s also given as both animal f e e d
equivalent (by taking a v e r a g e efficiency of d r a f t h o r s e s a n d mules to b e f o u r
p e r c e n t , i.e., by multiplying wind a n d water power s e r i e s by t h e f a c t o r 25) and as
d i r e c t mechanical e n e r g y inputs.
Merchant Vessels
Tonnage of m e r c h a n t v e s s e l s disaggregated by propulsion system into sailing,
s t e a m e r s , a n d motor s h i p s a n d by s t r u c t u r a l material into wood a n d metal i s from t h e
U. S . Department of Commerce (1970) f o r t h e p e r i o d 1789 to 1970. Total tonnage of
t h e f l e e t is from t h e U. S . Department of Commerce (1981) f o r t h e p e r i o d 1 9 7 1 to
1980.
Number of Cars. Buses and Trucks
Number of c a r s , buses, and t r u c k s in u s e in t h e United S t a t e s are r e p r e s e n t e d
by t h e motor vehicle r e g i s t r a t i o n s . Registrations are from Epstein (1928) for t h e
p e r i o d 1 8 9 5 to 1900, from Ward's Automotive Yearbook (1974, 1984) f o r t h e p e r i o d
1900 to 1982.
Mileage of Roads
The mileage of u r b a n , r u r a l , a n d s u r f a c e d r o a d s i s from t h e U. S . Department of
Commerce (1970, 1975, 1980, 1981, 1983, 1984). The mileage of s u r f a c e d r o a d s is
calculated as t h e sum of s u r f a c e d r u r a l r o a d s a n d all u r b a n ( e a r l i e r municipal)
streets. Total mileage of all r o a d s is t h e sum of r u r a l r o a d s a n d u r b a n s t r e e t s .
Number of Non-Farm Horses (and Mules) and Cars
Number of h o r s e s a n d mules d i s a g g r e g a t e d by t y p e of u s e are from F i s h e r
(1974). Only non-farm h o r s e s a n d mules (those used f o r t r a n s p o r t ) are included in
t h e d a t a set. Number of cars in u s e are from Ward's Automotive Yearbook (1974,
1984) as above.
Production of Buggies, Camages. Sulkies, and Cars
Production of buggies, c a r r i a g e s , a n d sulkies a n d f a c t o r y sales of cars are
from t h e U. S . Department of Commerce (1970). F a c t o r y sales of horse-drawn
"chicles were n o t available, b u t in t h i s case t h e inventories of new vehicles are
p r o b a b l y small so t h a t t h e d i f f e r e n c e between sales a n d production i s not v e r y
large.
Substitution of Open b y Closed Car Bodies
P e r c e n t a g e of closed car production t o t o t a l p a s s e n g e r car output f o r t h e
period 1 9 1 5 t o 1926 is from Epstein (1928).
Factory-Installed Equipment
Factory-installed equipment t r e n d s , including transmissions, d i s c b r a k e s , a i r
conditioning, r a d i a l t i r e s , and power s t e e r i n g , f o r t h e whole p e r i o d 1948 t o 1982 a r e
from Ward's Automotive Yearbook (1974 and 1984). The p e r c e n t a g e of three-speed
transmissions was r e c o n s t r u c t e d from t h e s h a r e s of automatic and o t h e r manual
transmissions.
Automatics include semi-automatics f o r e a r l i e r y e a r s .
Air
conditioning includes both manual and automatic. Radial t i r e s were not r e p o r t e d
p r i o r t o 1 9 7 3 e x c e p t f o r 4649 r a d i a l t i r e installations on 1972 Eldorados r e p o r t e d
by t h e Cadillac Division of General Motors. Power s t e e r i n g installations were not
r e p o r t e d p r i o r t o 1952.
Emission Controls
Number of p a s s e n g e r cars with emission c o n t r o l s (whether o r not t h e c o n t r o l s
are in o p e r a t i o n ) are from t h e U. S. Department of Commerce (1983). Altogether,
d a t a were grouped into f o u r b r o a d classes: c a r s without explicit emission controls,
c a r s with some emission c o n t r o l s [having some o r a l l of t h e following controls:
c r a n k c a s e , e x h a u s t (hydrocarbon and c a r b o n monoxide emissions), fuel evaporation
from t a n k s and c a r b u r e t o r s , and lower nitrogen oxide emissions controls], and c a r s
with catalysts.
Cons~unptionof Gasoline
Consumption of gasoline, both leaded and unleaded, r e p r e s e n t s domestic motor
gasoline supply (production plus imports less net i n c r e a s e in primary stocks) i s
given in bbls p e r day and i s from t h e U. S. Department of Commerce (1983).
Intercity Passenger Traffic
Volume of domestic i n t e r c i t y p a s s e n g e r t r a f f i c disaggregated by p r i v a t e c a r s ,
buses, domestic airways, r a i l r o a d s , and inland waterways (ships) i s given in
passenger-miles p e r y e a r a n d i s from t h e U.S. Department of Commerce (1970, 1975,
1980, 1981, 1983).
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Marchetti, C., 1979, E n e r g y Systems - The B r o a d e r Context, Technological
Forecasting and Social Change, 14:191-203.
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Analysis.
Marchetti, C., 1983, The Automobile in a System Context, The P a s t 8 0 Years and t h e
Next 20 Years, Technological Forecasting and Social Change, 23:3-23.
Nakicenovic, N., 1979, Software P a c k a g e f o r t h e Logistic Substitution Model, RR79-12, Laxenburg, Austria: International Institute f o r Applied Systems
Analysis.
Nakicenovic, N., 1984, Growth t o Limits, Long Waves a n d t h e Dynamics of
Technology, Vienna.
Putnam, P . C., 1953, Energy in t h e F u t u r e , N e w York: D. Van Nostrand Co.
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S c h u r r , S. a n d B. N e t s c h e r t , 1960, Energy in t h e American Economy, 1850-1975, An
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R e s o u r c e s f o r t h e F u t u r e , Inc. by The Johns Hopkins P r e s s .
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Colonial Times to 1970, Bureau of t h e Census, Washington D. C.
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Automotive Yearbook,
Communications Inc.
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Thirty-Sixth
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Detroit:
Ward's
Ward's
Automotive Yearbook,
Communications Inc.
1984,
Forty-Sixth
Edition,
Detroit:
Ward's