Dematerialization of Production
"The Dematerialization angle
In the recent period we have been “relatively dematerializing”
“Dematerialization” is not the complete elimination of a particular material, but a substantial reduction of material used, be it a finished item, a service rendered (per unit of power delivered by a prime mover, per unit of computer performance) or a unit of national economic product. This relative dematerialization, has been one of the key trends in modern manufacturing whose quest for higher productivity and lower prices has brought reduced use of materials (be they traditional and inexpensive, or modern and costly) for products ranging from beverage cans to jetliners, and from simple structural elements in buildings to computers.
There are still other categories of dematerialization to consider. Herman et al. (1990, p. 334) argued that from an environmental point of view it is not the reduced unit mass of products that matters (as smaller and lighter items could be of inferior quality and their more frequent replacement could generate more waste) but that dematerialization “should perhaps be defined as the change in the amount of waste generated per unit of industrial products.” This might be a desirable and revealing choice, but collecting the necessary information about all possible waste-streams and coming up with relative valuations of different emissions or effluents (as mass reduction of one waste-stream can be replaced by a much smaller mass release of a compound that is more harmful or more durable) is obviously challenging. LCA's (life-cycle analysis) goal is to provide precisely that kind of information but, as shown in the preceding chapter, such assessments should be used with caution.
Similarly, two other measures of dematerialization – declining consumption of goods or lower use of energy per unit of economic product – face a number of intractable data challenges relating to the accounting for overall economic output; while adjustments for inflation can be done fairly easily and with acceptable uncertainty, conversions to purchasing power parities (PPPs) are far more questionable.
Moreover, energy use per unit of GDP may be a common measure of an economy's overall energy intensity but (even when setting aside the uncertainties inherent in converting various energies to a common denominator) a closer look shows that it is fundamentally flawed, that its narrow interpretation gives very limited insights and that it is only a poor proxy for tracing both historical and recent changes of material consumption in growing economies. I will review, deconstruct, and assess all of these dematerialization measures.
Examples of airplane engines, computers, etc…
Relative Dematerializations: Specific Weight Reductions. Reduction of material inputs in production can be accomplished in 4 principal ways:
1. by gradual improvements that do not involve new materials;
2. by substitutions (often relatively rapid) of constituent materials with lighter or more durable alternatives;
3. by intensified recycling, particularly effective in those cases where reusing brings major energy savings;
4. by the introduction of entirely new devices that perform the desired functions with only a fraction of the mass needed for their predecessors.
We can list examples: aluminum cans, prime mover engines, etc...
Relative dematerialization has been a key reason for falling costs, greater affordability, and mass diffusion of successive generations of products, as well as for preventing significant levels of environmental pollution and degradation
In an overwhelming majority of cases, these complex, dynamic interactions of cheaper energy, less expensive raw materials, and cheaper manufacture have resulted in such ubiquitous ownership of an increasing range of products and more frequent use of a widening array of services that even the most impressive relative weight reductions accompanying these consumption increases could not be translated into any absolute cuts in the overall use of materials. Indeed, there can be no doubt that relative dematerialization has been a key (and not infrequently the dominant) factor promoting often massive expansion of total material consumption. Less has thus been an enabling agent of more.
This counterintuitive phenomenon was first described in relation to energy consumption by English economist William Stanley Jevons (cfr the Jevons Paradox:
“It is wholly a confusion of ideas to suppose that the economical use of fuels is equivalent to a diminished consumption. The very contrary is the truth. As a rule, new modes of economy will lead to an increase of consumption according to a principle recognised in many parallel instances” (Jevons, 1865).
Savings arising from the increasing efficiency of energy conversions have been a factor in promoting their more frequent use and in driving up the overall use of fuels and electricity.
Examples abound: just compare the number of lights and electronic gadgets in an average household in 2010 with the total of their much less efficient predecessors in 1930. In 1930, even in the richest countries, a typical household had just a few (six to eight) lights, a radio, and perhaps a small electric stove; 80 years later it has more than two dozen lights, an array of electrical appliances (including such major energy consumers as refrigerators, stoves, toasters, washing machines, dishwashers, clothes dryers, and air conditioners) and a still growing range of electronic gadgets ranging from TVs and CD players to game boxes, personal computers, and cellphones. Clearly, relative dematerialization is decidedly one of those “many parallel instances” noted by Jevons as less means more.
This failure to reduce car mass is even worse when assessed in per capita terms, because between 1920 and 2010 the rate of vehicle ownership increased from fewer than 8 cars/100 people in 1920 to 27/100 people cars in 1950. After this, it became common for a family to own two or more vehicles: in 1950 only about 3% of US households had a second car, by 1965 that share reached 24%, and by 2011 it was nearly 40%, with about 20% of all families having three or more cars at just over 80 vehicles/100 people. Between 1920 and 2011 relative registrations thus increased almost exactly 10-fold, and even after completely eliminating the effects of the intervening population growth (from 106 to 308 million people) which would have, everything else being equal, resulted in nearly three times as many vehicles on the road, the combined effect of additional power, higher weights, and higher rate of ownership had increased the average per capita mass of materials deployed in passenger cars registered in 2011 nearly 35-fold when compared to their mass in 1920." (Google doc)
The evolution of American passenger cars provides another well-documented example of an impressive relative dematerialization