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Energy
Use, Efficiency, and the Future
Garrett
Hardin who originated the idea of the Tragedy of the Commons, summarizes
the two laws of Thermodynamics in terms of human significance as:
"You
can't win, you are sure to lose;
and - you can't get out of the game."1
Whether
we can get more "out of the game" is the central question of
energy production. The examples above show what a small fraction of the
input potential energy is actually used as output work. Designing for
energy efficiency means in order to get a higher ratio of output, the
input needs to become a central concern of intelligence design and practice.
Most of
the energy planning is done by looking at the supply side. We examine
how we can increase the supply of the resource in question, rather than
by asking how the demand side (all our uses of energy) can be managed.
Energy availability and use are good indicators of the standard of living
in our technological world. In the U.S. the "average consumption
per capita" is 55 barrels of oil. In the poorer countries, the consumption
is 6 barrels per year. Figure 20 shows the projections of world energy
supplies from 1970-2020. The increased coal supply is based on mining
coal that is harder (and hence more costly) to extract.
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Figure
20: World Energy Consumption by Fuel Type, 1970-2020.
Sources: History: Energy Information Administration (EIA),
Office of Energy Markets and End Use, International Statistics
Database and International Energy Annual 1997, DOE/EIA-0219 (97)
(Washington, DC, April 1999). Projections: EIA, World Energy Projection
System (2000).
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Demand-side
management instead of or in addition to supply side management would mean
a focus on increasing efficiency of use and considerations of how to reduce
the demand. The CAFE (Corporate Average Fuel Economy) standards legislated
in the U.S. in 1980's required a certain level of fuel efficiency of U.S.
automobiles. By demanding that the corporations figure out an overall
fuel rating for all their fleets, the decisions on design and distribution
of big and small cars in the total fleet were left to the industry, as
long as the total corporate fuel economy goals were met.
There are
also some efforts to recapture some of the "waste energy" from
the processes of energy generation. Co-generation described in Figure
21 is an example of industries working together to see how exchanges of
energy and materials could minimize waste.
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Figure
21: Co-generation.
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An Example
of "Waste Power" Use
An unusual example of such a partnership network in Denmark is show in
Figure 22. It is the result of 10 years of planning, and involves exchange
of water, steam, gas, and gypsum.
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Figure
22: Industrial Ecosystem.
Source: Allenby and Graedel, "Defining the Environmentally
Responsible Facility."
Measures of Environmental Performance and Ecosystem Condition. National
Academy Press: Washington, D.C.
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Four companies
(a power plant, a refinery, a gypsum facility for producing wall board,
and a pharmaceutical plant) effect the exchange shown in Figure 22. The
"waste" products from the power station (including heat in the
form of warm water) are used to warm the greenhouse and other facilities.
Such a co-generation system provides an industrial ecosystem with a much
higher efficiency for overall energy use than if any of the organizations
had organized independently for their material and energy needs. The ten
years of planning required shows that such processes take time to explore
the possibilities, develop the relationships, then plan and execute.
[1] Hardin, Garret. Filters Against Folly: How
to Survive Despite Economists, Ecologists, and the Merely Eloquent.
Viking Press, 1985. (p. 173)
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