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以綠色導向政策探討低經濟價值再生材料之回收供應鏈
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can only be setup for one set of parameters, the percentage usage of recycled PVC will not
change easily.
We assume the suppliers in PVC closed-loop supply chain have
c
x
= 0.2 for the virgin
VPC and
c
y
= 0.4 for the recycled PVC. The environmental benignity factor
κ
= 0.2. There
are 3 manufacturers get
σ
i
proportion of recycled materials from the EDRM processor and
get virgin materials for the rest of inputs. If the system use virgin materials only, the 3
manufacturers will all produce quantities
q
0
= [(0.05 0.05 0.05)] because all of them have the
same
= 0.4.
Furthermore, for a market providing both virgin and recycled materials but no
government intervention, the 3 manufacturers will produce quantities
q
(2S–)
= [(0.0333 0.0267
0.0200)]. The ingredients of the 3 manufacturers are shown in the second column of Table 1.
Without the help of government, the cost of providing EDRMs is more expensive than that
of virgin materials. Therefore, containing more EDRMs causes a decrease in production and
Manufacturer 3 held the least market share.
Table 1 Parameters and Equilibrium Results for the 3 Manufacturers
Manu.
σ
i
ξ
i
c
mi
w
xi
*
w
yi
*
q
i
*
π*
mi
1
0.3
0.6
0.4
0.2814 0.0533 0.0178 0.0003
2
0.4
0.5
0.4
0.2847 0.0473 0.0412 0.0017
3
0.5
0.4
0.4
0.2880 0.0413 0.0645 0.0042
To evaluate the amount of tax and subsidy, we calculate
ξξ
= 0.2075,
σσ
= 0.1400,
ξσ
= 0.1300,
ξm
= 0.1500, and
σm
= 0.1200. The amounts
become
ϕ
= 0.2065 and
ε
= 0.6935.
We compare the profits and social welfares between policy framework (2S
–
) and (2S).
With the government intervention, both social welfare and company profit become higher,
that is,
SW
*
(2
S
–)
= 0.0320 and
SW
*
(2
S
)
= 0.0751 while
= 0.0022 and
= 0.0062.
Manufacturer 3 used the most EDRM and emitted least effluent so that Manufacturer 3 has
been encouraged to produce the most in the market.