472
G. Miyake et al.
The first and second terms of Eq. 31.3 represent resource inputs during the product
life cycle. A and a in the first term denote inputs of virgin material into the product
system, while B and b” in the second term indicate inputs of recycled materials.
The sum of these terms represents the resource impact of input resources. The third
term of Eq. 31.3 expresses the reduction in environmental impact arising from the
reuse of resources due to product recycling after use. Here X is the environmental
impact coefficient when the product is made from virgin raw materials and X
is the
environmental impact coefficient when the product is made from recycled materials.
X is synonymous with A, while X’ is synonymous with B. In other words, when a
certain material is generated by recycling instead of from virgin raw materials, the
corresponding reduction of raw resource use is expressed by an environmental impact
coefficient. This coefficient is derived from the difference between the corresponding
coefficients. By multiplying that result by x
, the weight of the recycled material, we
obtain the amount of reduced resource impact.
31.2.4 Comparison of Resource Impact Coefficients
Generally, two types of environmental impact coefficients represent resource impact.
One is a material footprint representing the environmental impact of land disturbance
caused by resource mining, which includes the total material requirement (TMR)
and the Ecological Rucksacks concept (Halada 2007). The other is a resource depletion characteristic coefficient that indicates exhaustion or scarcity of resources; it
includes environmental design of industrial products (EDIP), 1/R based on recoverable reserves, and abiotic depletion potential based on the ultimate resource amount
(Itsubo and Inaba and LIME 2, Japan environmental management association for
industry (JEMAI) 2010).
The viewpoints of each coefficient are totally different, and each has its advantages
and disadvantages, so it is difficult to select one for this indicator. Although one could
calculate all these coefficients and then weight each of them to create an integrated
index, for this paper we decided to evaluate resource efficiency using just one of the
possible coefficients at a time and compare the results.
31.2.5 Representation of the Purpose of This Paper Using
Indicators
Based on the resource efficiency indicator above, the evaluation items 1 through 3
as described in 2.1 can be expressed as follows:
(i) By multiplying the weight of each resource by the environmental impact
coefficient, the resource impact for each material type is expressed.
G. Miyake et al.
The first and second terms of Eq. 31.3 represent resource inputs during the product
life cycle. A and a in the first term denote inputs of virgin material into the product
system, while B and b” in the second term indicate inputs of recycled materials.
The sum of these terms represents the resource impact of input resources. The third
term of Eq. 31.3 expresses the reduction in environmental impact arising from the
reuse of resources due to product recycling after use. Here X is the environmental
impact coefficient when the product is made from virgin raw materials and X
is the
environmental impact coefficient when the product is made from recycled materials.
X is synonymous with A, while X’ is synonymous with B. In other words, when a
certain material is generated by recycling instead of from virgin raw materials, the
corresponding reduction of raw resource use is expressed by an environmental impact
coefficient. This coefficient is derived from the difference between the corresponding
coefficients. By multiplying that result by x
, the weight of the recycled material, we
obtain the amount of reduced resource impact.
31.2.4 Comparison of Resource Impact Coefficients
Generally, two types of environmental impact coefficients represent resource impact.
One is a material footprint representing the environmental impact of land disturbance
caused by resource mining, which includes the total material requirement (TMR)
and the Ecological Rucksacks concept (Halada 2007). The other is a resource depletion characteristic coefficient that indicates exhaustion or scarcity of resources; it
includes environmental design of industrial products (EDIP), 1/R based on recoverable reserves, and abiotic depletion potential based on the ultimate resource amount
(Itsubo and Inaba and LIME 2, Japan environmental management association for
industry (JEMAI) 2010).
The viewpoints of each coefficient are totally different, and each has its advantages
and disadvantages, so it is difficult to select one for this indicator. Although one could
calculate all these coefficients and then weight each of them to create an integrated
index, for this paper we decided to evaluate resource efficiency using just one of the
possible coefficients at a time and compare the results.
31.2.5 Representation of the Purpose of This Paper Using
Indicators
Based on the resource efficiency indicator above, the evaluation items 1 through 3
as described in 2.1 can be expressed as follows:
(i) By multiplying the weight of each resource by the environmental impact
coefficient, the resource impact for each material type is expressed.