0
0e+00 1e+05 2e+05
Certified solar power generation facilities (kW)
3e+05 4e+05 5e+05 6e+05 7e+05
50000 100000 150000 200000
Average land price (kWh/m
2 /day)
250000 300000 350000
Fig. 21.4 Relationship between average land price and certified solar power generation facilities
using local regression smoothing (loess) (horizontal axis, JPY/m
2
; vertical axis, kW)
Table 21.1 Variables entered into regression analysis model by stepwise method
Insolation (x)
Land price (z)
Cross terms
x
z
x  z
x
2
z
2
x  z
2
exp(x)
z
3
x  z
3
log(z)
x  log(z)
x
2 Â z
x
2 Â z
2
x
2 Â z
3
x
2 Â log(z)
exp(x) Â z
exp(x) Â z
2
exp(x) Â z
3
exp(x) Â log(z)
21 Opportunities for Renewable Energy Introduction Through Feed-in Tariff (FIT). . .
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