Handbook IO in IE

Chapter 27

Waste Input-Output Analysis, LCA and LCC Shinichiro Nakamura and Yasushi Kondo

Introduction Any economic activity generates waste of some kind, which needs to be treated by some waste treatment method. Corresponding to any flow of goods among different sectors of the economy, there exists the associated flow of waste involving waste treatment sectors. The conventional IOA was originally developed to represent the intersectoral flow of goods and hence is not designed to take account of the flow of waste associated with it. Consequently, in its conventional form, IOA is not able to take proper account of the effects that result from the interaction between the flows of goods and wastes. The pioneering study in the field of environmental IOA (EIO) that is relevant to waste management issues is the Leontief pollution abatement model (Leontief 1970, 1972). Leontief extended the conventional IOA to take account of the emission of pollutants, their elimination activity, and the interdependence between conventional goods-producing sectors and pollution abatement sectors. With regard to their relevance to issues of waste management, the Leontief pollution abatement model and its extension by Faye Duchin (1990) can be characterized by the fact that they assume the existence of a strict one-to-one correspondence between a pollutant (waste) and its abatement (waste treatment) method. However, in waste management, the joint treatment of a wide range of different types of waste in a single treatment method is commonly observed. It is also true that a wide range of different treatment methods can be applied to a given type of waste. In short, the one-to-one correspondence between waste types and treatment methods does not hold in the empirically relevant case of waste management that involves a large number of waste types and treatment methods. The assumption in the Leontief EIO model is not consistent with the reality of waste management. S. Nakamura (!) and Y. Kondo School of Political Science and Economics, Waseda University, Tokyo, Japan e-mail: [email protected] S. Suh (ed.), Handbook of Input-Output Economics in Industrial Ecology, Eco-Efficiency c Springer Science+Business Media B.V. 2009 in Industry and Science 23, !

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S. Nakamura and Y. Kondo

The WIO (waste input-output) model (Nakamura 1999; Nakamura and Kondo 2002) generalized the Leontief EIO model to make it applicable to waste management issues. It can deal with an arbitrary combination of treatment methods applied to an arbitrary combination of waste types provided that the combinations are technically feasible. The number of waste types and treatment methods can be set arbitrarily and are not required to be equal. Furthermore, it can take account of waste generated from virtually any waste source in the economy, including municipal solid waste (MSW) from final demand sectors, industrial and commercial waste from the goods- and service-producing sectors, and treatment residues from waste treatment sectors. In this chapter we explain the basic concepts of the WIO table and model, and illustrate its application to LCA (Life Cycle Assessment) and LCC (Life Cycle Costing). Section “Waste Input-Output Table” first introduces the basic notations and explains the basic structure of the WIO table. Section “The WIO Model” is devoted to the derivation of theoretical WIO models. In the conventional IOA it is well known that corresponding to a quantity model there does exist a cost/price model which is dual to it. The duality of the conventional IOA does not apply to the WIO quantity model due to its peculiar natures except under special conditions. Still, it is possible to obtain a cost/price counterpart of the WIO model. Section “Application of WIO to LCA and LCC” illustrates the application of the WIO models to LCA and LCC for a case study of the recycling of end-of-life electric appliances. A brief mention of some recent applications and extensions of WIO closes the chapter.

Waste Input-Output Table We shall first introduce notations. Let there be nI goods- and service-producing sectors (henceforth “goods sector”), nII waste treatment sectors, nW waste types, and n WD nI C nII . We define the sets of natural numbers referring to each of these sectors and waste types by N I WD f1; : : : ; nI g, N II WD fnI C 1; : : : ; nI C nII g, N WD N I [ N II , and N W WD f1; : : : ; nW g. We then denote, for sector j (j 2 N /, its output by xj , the input from sector i (i 2 N / by Xij , and the generation and input of waste k (k 2 N W / by Wkj˚ and Wkj" , respectively. The flow of waste is net of intrasectoral recycling, and is measured in a physical unit. For a waste treatment sector, its “output” refers to the amount of waste it treated. Similarly, we denote the final demand for i (i 2 N / by XiF , the generation of waste k (k 2 N W / from the final ˚ " demand sector by WkF , and the input of waste k into the final demand sector by WkF . Table 27.1 shows a schematic representation of the waste input-output table (WIOT). Bold-faced capital letters refer to matrices and small letters to vectors. For ˚ W I instance, W˚ #;I refers to an n ! n matrix, the .k; j /-element of which is Wkj , XI;II to an nI ! nII matrix the .i; j /-element of which is Xi;nI Cj , and xI to an nI -vector of xj ’s. The generation of waste from waste treatment sectors W˚ #;II represents the outcome of waste conversion in treatment processes such as the generation of ash from an incinerating process or the generation of metals from a shredding process.

27

Waste Input-Output Analysis, LCA and LCC

563

Table 27.1 Schematic Form of Waste Input-Output Table Goodsproducing sectors

Treatment sectors

Final demand

Total

Goods input

XI;I

XI;II

XI;F

xI

Waste generation

W˚ !;I

W˚ !;II

W˚ !;F

w˚

E!;II

E!;F

e

Waste input

W" !;I

Env. load emission E!;I Value added

V!;I

W" !;II V!;II

W" !;F

w"

On the other hand, W" #;II refers to the input of waste for use in treatment processes but not to the waste feedstock to be treated. As an accounting framework, the WIOT is a special case of NAMEA (Haan and Keuning 1996), which is characterized by a detailed description of waste management. We denote by Wkj WD Wkj˚ " Wkj" the net generation of waste k from sector j . When Wkj > 0, sector j generates greater amount of waste k than it uses as input, and creates a positive demand for waste treatment. On the other hand, when Wkj < 0, sector j reduces the amount of waste k that has to be treated as waste. The sum of Wkj ’s for all j , wk D wk˚ " wk" , then gives the total amount of waste k that undergoes waste treatment. It is assumed that Wkj˚ and Wkj" are measured net of the input of waste k generated within sector j ; intra-sectoral transactions of waste are netted out. This excludes the case where Wkj˚ and Wkj" take non-zero values simultaneously; hence, we have Wkj˚ # Wkj" D 0;

.k 2 N W ; j 2 N [ fFg/:

(27.1)

The WIO Model The Quantity Model The conventional IOT is a square matrix with an equal number of columns and rows. In contrast, the WIOT is non-square because in general nW > nII holds and there is no one-to-one correspondence between waste types and treatment processes (Nakamura and Kondo 2002). The non-squareness of the WIOT does not pose any problem for merely descriptive purposes. For the purpose of developing an analytical model, however, this feature is quite inconvenient, and it is necessary to convert the matrix into a square one. The conversion is facilitated by an nII ! nW matrix, S, termed allocation matrix, the .i; j /-component of which refers to the share of waste j that is treated P by treatment method i (Nakamura and Kondo 2002). By definition sij $ 0 and i sij D 1.

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Multiplication from the left by S converts the net waste generation in Table 27.1 into the net input of waste treatment services XII;I D S W#;I and XII;II D S W#;II , and the net amount of waste treated into the nII -vector of output of waste treatment sectors xII D Sw. Denote by A the matrix of conventional input coefficients and by G the matrix of net waste generation coefficients. Adding appropriate suffixes referring to goods production and waste treatment, the flow of goods and net waste generation in Table 27.1 can then be given by "

xI w

#

"

AI;I D G#;I

AI;II G#;II

#"

xI xII

#

"

# XI;F C ; W#;F

(27.2)

As mentioned above, the matrix inside the first square brackets on the right hand side is not square because G#;II is not square. Multiplication of the lower half elements of Equation (27.2) from the left by S yields a square one, the WIO quantity model "

xI xII

#

D

"

AI;I

AI;II

SG#;I

SG#;II

#"

xI xII

#

C

"

XI;F W#;F

#

;

(27.3)

which can be solved as usual provided the inverse matrix exists: "

xI xII

#

D

"

AI;I I" S G#;I

AI;II S G#;II

# !$1 "

# XI;F : S W#;F

(27.4)

Let there be nE environment loading factors. Write R#;I and R#;II for matrices of emission of these factors per unit of goods production and waste treatment. The vector of total emissions e is then given by eD

!

R#;I R#;II

"

I"

"

AI;I

AI;II

S G#;I

S G#;II

# !$1 "

XI;F S W#;F

#

C E#;F :

(27.5)

The environmental IO (EIO) model of Leontief (1970, 1972) and Duchin (1990) corresponds to a special case of the WIO model where S is an identity matrix of order nII . Implicit in the EIO model is the assumption that there exists for each pollutant (waste) one and only one abatement (treatment) method that treats no other pollutant (waste) but that pollutant (waste). This condition is hardly applicable to the reality of waste management because, in general, there is no one-to-one correspondence between a waste and its treatment method. It is usually the case that a multiplicity of treatment methods can be applied to a given solid waste, either separately or jointly. For instance, garbage can be composted, gasified, incinerated, and/or landfilled. Any of these methods can be applied separately or in combination. On the other hand, any solid waste can be landfilled.

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565

The WIO represents a significant generalization over the EIO as regards its implications for waste management. First, because the allocation matrix S is not required to be square, the condition nII D nW is no longer necessary. The number of waste types and that of treatment methods can be arbitrary. Secondly, it can handle the case where a single treatment method is applied to multiple types of waste, because each row of S can contain more than one non-zero element. Third, it can handle the case where several treatment methods are jointly applied to a single type of waste, because each column can contain more than one non-zero element. These cases were excluded in the EIO model (see Nakamura and Kondo 2002 for further details of the WIO quantity model).

The Price Model We now turn to the aspect of cost and price of the WIO model. Let pj be the price of output of sector j .j 2 N /; pkw be the price of waste k 2 N w , Vj be the cost for primary factors of production that includes depreciations as well as taxes less subsidies, and Ukj > 0 be the portion of Wkj˚ that was used as input in sectors other than sector j . This explicit consideration of the sale and purchase of recovered waste materials distinguishes the definition of costs in the WIO from that of the conventional IOA. The sale of recovered waste materials is an important source of revenue for waste recyclers. A typical example is the disassembly of discarded automobiles, the major revenue source of which has been the sale of scrap metal to steel makers operating electric arc furnaces. There are, however, cases where the price of waste materials is negative, that is, waste materials are “accepted” with a charge by the user. For instance, some Japanese steel makers operating blast furnaces accept waste plastics with a charge and use them as reduction agents together with pulverized coal. The price of waste can thus become negative. Based on its sign condition, three cases can be distinguished: the waste is valuable when pkw > 0; it has no value but can be accepted by other sectors as input with no charge when pkw D 0; and it has no value and its acceptance needs a positive charge when pkw < 0. Henceforth, Ukj is called “sale of waste” regardless of whether the price of waste k is positive, zero, or negative. In the input-output account system we have the identity that equates the value of output to the total cost. Considering the trade of waste, this identity can be given for sector j .j 2 N / by: # $ X X X X ˚ " pi aij xj C pl slk gkj xj " Ukj C pkw gkj xj pj xj D i2N I

"

„

X

ƒ‚ .a/

…

l2N II

„

pkw Ukj C Vj : „ƒ‚… k2N w .e/ „ ƒ‚ … .d/

k2N w

ƒ‚ .b/

…

k2N w

„

ƒ‚ .c/

…

(27.6)

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The cost can be decomposed into five parts: (a) the cost for the input of goods, (b) the cost for waste treatment, (c) the cost for the input of waste materials, (d) the revenue from the sale of waste materials, and (e) the cost for the input of primary factors. The terms (b), (c), and (d) are unique to the WIO price model. When there is no recycling, Ukj D 0 holds for all k and j , and the terms (c) and (d) vanish, while the term (b) reduces to the treatment cost of wastes generated in the sector. The term (b) indicates that the amount of waste for treatment is reduced by the amount of Ukj . The sale of waste materials at positive prices can reduce the cost of production or treatment in two ways. First, it can reduce the cost directly by creating a new source of revenue other than the sale of “main” output. The term (d) refers to this component. Secondly, it can reduce the waste treatment cost that would have been necessary if the waste materials were not sold but had to be treated at a positive charge. The term (b) refers to this component. On the other hand, the sale of waste at negative prices reduces the production cost of the sectors that use the waste as input. Rearranging the terms yields the following expression, which shows the contribution of the sale of waste materials to the cost in a more explicit way. pj x j D

"

X

i2N I

pi aij xj C

„

ƒ‚ .a/

X

pkw

k2N W

„

…

C pl

X

pl

l2N II

„

X

k2N W

ƒ‚

X

k2N w

˚ slk gkj xj C

ƒ‚

…

.f/

!

slk Ukj CVj ;

.g/

X

k2N w

„

" pkw gkj xj

ƒ‚ .c/

…

(27.7)

…

Here, the term (f) refers to the waste treatment cost that would have been necessary if no waste materials were sold. When waste is sold to other sectors, it can affect the cost via the term (g). The extent to which the cost can be reduced by the sale of waste depends on the sign condition of the expression inside the parentheses of (g). When pkw > 0, the sale of waste certainly reduces the cost of production. It is important to note that even if pkw % 0, the sale of waste could reduce the cost as long as the following condition is satisfied: pkw C

X

l2N II

pl slk > 0

,

X ˇ wˇ ˇp ˇ D "p w < pl slk : k k

(27.8)

l2N II

This refers to the case where the sale of waste to other sectors at negative prices costs less than submitting it to waste treatment. The term Ukj plays a vital role in “the cost equation (27.7)”. It does not, however, occur in the systems of Equations (27.3) and (27.4) for the quantity model. It is necessary to establish the relationship between Ukj and the elements occurring in

27


567

the quantity model. For this purpose, let rk be the average rate of recycling of waste k defined as follows, , , X X X X " ˚ Wkl Wkl D Ukl Wkl˚ ; (27.9) rk WD l2N [fFg

l2N [fFg

l2N [fFg

l2N [fFg

where the second equality follows from Equation (27.1), which implies Wkj" D 0 when Ukj > 0. We now assume that for a given waste its rate of recycling is the same across the sectors in N : Ukj =Wkj˚ D rk ;

.Wkj˚ > 0; k 2 N W ; j 2 N /:

(27.10)

˚ , we obtain Recalling the definition of gkj ˚ xj rk : Ukj D Wkj˚ rk D gkj

(27.11)

Insertion of Equation (27.11) into (27.7) yields the following expression of the cost equation: pj x j D "

X

i2N I

pi aij xj C

X

pkw

k2N w

C

X

k2N w

l2N II

X

X

pl

pl slk

l2N II

!

˚ slk gkj xj C

˚ xj rk gkj

X

" pkw gkj xj

k2N w

(27.12)

C Vj :

Division of both the sides by xj yields the following price equation: pj D

X

i2N I

" D

X

i2N I

pi aij C

X

k2N w

X

k2N W

X

l2N II

X

l2N II

X

pl

l2N II

pkw C

k2N w

X

C

pi aij C

˚ slk gkj C

!

X

" pkw gkj

k2N w

˚ pl slk rk gkj C vj

pl

X

k2N w

slk .1 "

(27.13)

˚ rk /gkj

" ˚ pkw .gkj " rk gkj / C vj ;

where vj refers to the unit cost of primary inputs used in sector j . Using obvious matrix notations, Equation (27.13) can be rewritten as ! pI

pII

"

! D pI

pII

"

"

AI;I S.I " D/G˚ I

! ˚ C p G" I " DGI w

AI;II S.I " D/G˚ II " ! " ˚ GII " DGII C vI

#

"

vII ;

(27.14)

568


or in a more compact way as " pDp

AI;# ˚

S.I " D/G

#

C pW .G" " DG˚ / C v;

(27.15)

where p D .pI ; pII / D .p1 ; : : : ; pn /, v D .vI ; vII / D .v1 ; : : : ; vn /, pW D .p1W ; : : : ; pnWW /, D is a diagonal matrix whose k-th diagonal component is rk , i.e., D D diag.r1 ; : : : ; rnW /, and I is an identity matrix of an appropriate order. Provided it is possible to solve Equation (27.15) for p, this solution can be given by ˚

W

"

˚

p D p .G " DG / C v

%

&

I"

'

AI;# S.I " D/G˚

( )$1

:

(27.16)

Comparing the inverse matrices occurring in Equation (27.16) and the quantity model Equation (27.4), we find that the former reduces to the latter if G" D 0 (and hence D D 0/, that is, when there is no recycling of waste.

Application of WIO to LCA and LCC WIO-LCA LCA is concerned with the comparison of the level of environmental loading that results from alternative scenarios for a given functional unit. Elements of scenarios may include alternative waste treatment or recycling technologies, alternative institutional regulations, and alternative lifestyles with regard to the use of appliances. In the WIO model, the introduction of a new treatment and/or recycling technology occurs as a change in the coefficient matrices (A, G, R/, the introduction of a new regulation occurs as a change in S, and a change in lifestyle occurs as a change in final demand vectors (XI;F , W#;F /. For instance, let !aij , !gij and !rij be the incremental changes in input, waste generation, and emission coefficients associated with the introduction of a certain scenario (for simplicity, we ignore the suffixes “I” and “II”). The new set of corresponding input, waste generation, and emission coefficients matrices A0 , G0 and R0 are then given by A0 D Œaij C !aij ", G0 D Œgij C !gij " and R0 D Œrij C !rij ". Furthermore, let S0 be the allocation matrix corresponding to the scenario. We can evaluate the impact associated with the scenario by comparing the new solution for Equation (27.5) based on A0 , G0 , S0 and R0 with the reference solution based on the coefficients before the change. Kondo and Nakamura (2004) conducted, among others, a WIO-LCA of the recycling of end-of-life electric home appliances (EoL-EHA), namely, TV sets, air conditioners, refrigerators, and washing machines, in Japan under the following three scenarios:

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569

Table 27.2 Environmental Effects of EoL-EHA Recycling (Kondo and Nakamura 2004 with updated data) Scenarios GWP Abiotic mineral resources Landfill (weight) Landfill (area)

Recycling

Recycling + DfD

$0.715 $0.184 $1.139 $1.520

$0.721 $0.187 $1.214 $1.677

Rate of change (%) relative to the case where all appliances are landfilled.

1. Landfilling (Lf): EoL-EHA are directly landfilled without any pretreatment, except for recovery and decomposition of chlorofluorocarbon (CFC) 12. 2. Recycling (Rc): EoL-EHA are subjected to an intensive material recovery process where aside from iron, plastics, glass, copper and aluminum are also recovered. Furthermore, the CFC11 contained in the urethane foam of refrigerators for insulation is also recovered and decomposed. Recovered iron, copper, aluminum, and glass are used respectively for electric arc steel making, copper elongation, aluminum rolling, and glass making as substitutes for virgin materials. Plastics are used as a reduction agent in blast furnaces in the iron and steel industry. 3. Recycling with design for disassembly (DfD): (Rc) is supplemented with additional implementation of DfD. This increases the efficiency of disassembling and the quality of recovered materials (plastics) as well, which makes possible a closed-loop recycling of some plastics. Based on detailed technical information, alternative sets of A, G and R were obtained that correspond to each of these scenarios. For instance, material recovery under (Rc) refers to elements of G˚ of the EoL-EHA disassembling process, and the recycling of recovered materials refers to elements of G" and A of the corresponding goods-producing sectors. The allocation of EoL-EHA to alternative treatment scenarios is formulated by alternative sets of S. Table 27.2 gives the major results obtained by use of the Japanese WIO table for 1995 (Nakamura 2003). It is found that the recycling of EoL-EHA is effective in reducing environmental load, and that the implementation of DfD works to augment this tendency.

WIO-LCC However excellent a product is environmentally, its potential for reducing environmental loading remains unexploited unless it is widely used in the economy. An important prerequisite for this is that the product be economically affordable as well. Life-cycle costing (LCC) is a means for evaluating the cost aspect of a product from the point of view of its whole life cycle including the use and EoL phases in addition to the manufacturing and distribution phases. In the following, the WIO

570


price model is applied to an LCC of the recycling of EoL-EHA, which was found environmentally sound. Under the current Japanese EHA recycling law, consumers are to bear the EoL cost when they discard appliances. In view of this, our major concern consists in evaluating the effects of internalizing the EoL cost on the unit cost of appliances. Compared with LCA, which is internationally standardized, there is no uniform understanding of the term life-cycle costing nor is there a standardized methodological framework that is commonly used in business (Rebitzer 2002). Because of its simplicity and close relationship to LCA, we have chosen to use the following definition of LCC (Rebitzer 2002): LCC WD R&D C MAT C TRNS C MANF C USE C EoL C TC;

(27.17)

where R&D, MAT, TRNS, MANF, USE, EoL, and TC refer to the costs for research and development, materials, transport/logistics, manufacturing, use, end-of-life, and transaction costs. An IO table depicts all monetary flows of inputs and outputs including the items MAT, TRNS, MANF, and TC so far as they refer to current expenditures, that is the term (a) of Equation (27.7). In the Japanese IO table, the current expenditure for research and development is also recorded as an input item. To the extent that the current expenditure for research and development recorded in the IO table (including WIO) corresponds to the above concept of R&D, implementation of the above LCC concept within an IO model is rather straightforward except for the terms USE and EoL. Because the use pattern of EHA remained the same for each of the scenarios considered, only EoL (to be more specific, EoL per unit of appliance i , eol i / needs to be additionally considered. In the following, the cost at the use phase is not considered. It is important to note that because Equation (27.16) encompasses the price (unit cost) of all the sectors including waste treatment, the price vector p actually includes eol i as one of its elements. Inclusion of eol i as an additional term to the right hand side of Equation (27.13) for appliance i then gives its life cycle cost per unit of output. Some remarks on the characteristics of WIO-LCC may be due. Its functional unit is a unit of appliance from its production to the end of its life. As for the treatment of time, it is static, and the comparison among alternative scenarios is based on the method of comparative statics. The cost refers to static or average annual cost: discounting is not considered. As for space, it is limited to the territory of Japan, though the cost of import is taken into account. Table 27.3 shows the results for two types of appliances for which detailed data were available (Nakamura and Kondo 2004). It is found that while internalization of the EoL cost in the manufacturing cost increases the unit cost of appliances by 4–5%, implementation of DfD can be effective to reduce the extent of cost increase. Recalling that DfD improves the environmental performance of recycling (Table 27.2), our results seem to indicate the effectiveness of an EcoDesign (DfD) strategy toward the realization of sustainable EHA manufacturing.

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571

Table 27.3 Effects of Internalizing the EoL Cost on the Unit Cost of Appliances Recycling Television sets Refrigerators

3.61 4.77

Recycling C DfD 3.07 3.86

The figures refer to the rate of change (%) in the unit cost of appliances that results from internalizing the end-of-life cost of EHA relative to the case where the cost is external and borne by consumers. The cost at the use phase is not included.

Concluding Remarks We close this chapter by introducing three recent applications/extensions of WIO. The analysis above has been static, and no aspect of the dynamic process, where goods are accumulated and then transformed into waste, was considered. Proper consideration of this dynamic aspect is of great importance for analyzing issues of durable waste such as buildings, structures, automobiles, and appliances. The issue of dynamics has been considered by Kazuyo Yokoyama (2004), who developed a dynamic version of the WIO quantity model and applied it to the life cycle of office buildings. Her major concern has been the effects on long-term recyclability of concretes which contain recycled materials. The conventional IOA does not consider the issue of the choice of technology from among a set of alternatives. This applies to the above description of WIO as well. Kondo and Nakamura (2005) have proposed a decision analytic extension of the WIO model based on linear programming, and applied it to explore the extent to which a given measure of eco-efficiency can be maximized by an appropriate combination of existing (technological and resource) potentials. Their results indicate the presence of a substantial potential for reducing the volume of landfill in Japan that remains unutilized. The final example of extension is concerned with our lifestyle, or the volume and composition of final demand, an issue which so far has been regarded as given. Our lifestyle (consumption pattern) is a major driving force of economic activity, and hence a major determinant of the associated environmental loading. In an attempt to evaluate the relationship between consumption patterns and waste generation, Koji Takase and Ayu Washizu 2004) have proposed a “Waste Score” for each consumer good, which refers to the ultimate landfill volume induced by the consumption per unit of the good.

References Duchin, F. (1990). The conversion of biological materials and waste to useful products. Structural Change and Economic Dynamics, 1(2), 243–262. Haan, M., & Keuning, S. (1996). Taking the environment into account: The NAMEA approach. Review of Income and Wealth, 42(2), 131–148.

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Kondo, Y., & Nakamura, S. (2004a). Evaluating alternative life-cycle strategies for electrical appliances by the waste input-output model. International Journal of Life Cycle Assessment, 9(4), 236–246. Kondo Y., & Nakamura, S. (2005). Waste input-output linear programming model with its application to eco-efficiency analysis. Economic Systems Research, 17(4), 393–408. Leontief, W. (1970). Environmental repercussions and the economic structure: An input output approach. Review of Economics and Statistics, 52(3), 262–271. Leontief, W. (1972). Air pollution and the economic structure: Empirical results of input-output computations. In A. Brody & A. P. Cater (Eds.), Input-output techniques. Amsterdam: NorthHolland. Nakamura, S. (1999). Input-output analysis of waste cycles. In First international symposium on environmentally conscious design and inverse manufacturing, Proceedings (pp. 475–480). Los Alamitos, CA: IEEE Computer Society . Nakamura, S. (2003). The waste input-output table for Japan 1995, version 2.2, http://www.f. waseda.jp/nakashin/research.html, January 2003 (accessed December 2004). Nakamura, S., & Kondo, Y. (2002). Input-output analysis of waste management. Journal of Industrial Ecology, 6(1), 39–64. Nakamura, S., & Kondo, Y. (2004). A hybrid LCC of electric home appliances based on WIO. In Proceedings of the International Conference on EcoBalance 2004, S2-2-3. Rebitzer, G. (2002). Integrating life cycle costing and life cycle assessment for managing costs and environmental impacts in supply chains. In S. Seuring & M. Goldbach (Eds.), Cost management in supply chains (pp. 128–146). Heidelberg, Germany: Physica-Verlag. Takase, K., & Washizu, A. (2004). An environmental housekeeping book by the waste input-output model. In Proceedings of the International Conference on EcoBalance 2004, S3-5-1. Yokoyama, K. (2004). Dynamic extension of waste input-output analysis. Journal of the Japan Society of Waste Management Experts, 15(5), 372–380, in Japanese with English summary.