The high number of large-scale solar power generation installations is related to
the setting of fixed purchase prices in Japan. The purchase price of solar power
generation is high and differentiated at two scales: less than 10 kW and more than
10 kW. However, as the scale of installation increases, the average cost of solar
power generation tends to decrease, yet the purchase price is set at the same level.
Thus, introduction of large-scale equipment leads to higher profits than for smallscale facilities, so large-scale solar power generation becomes more popular.
When a facility reaches 50 kW, an enormous amount of additional cost is
involved, so the number of installations drops after 50 kW and increases again for
much larger facilities. In order to promote local production for local consumption,
rooftop space should be better utilized (especially in large cities with high power
demand)
5 than under the current system.
In Germany, small- to medium-sized (>0.01 and <0.04 MW) rooftop installations have the highest total capacity (Fig. 21.9). Overall, equipment with a capacity
of 1 MW or less accounts for 74% of the total. By installation type, rooftop solar
power generation facilities account for 73%. Purchase price is subdivided according
to the five scales and installation configurations (rooftop and ground) shown in
Fig. 21.9. The smaller the scale, and the higher the purchase price for rooftop
installation, the larger the amount of small-scale, rooftop solar power generation
installed.
There are merits to introducing mainly large-scale power generation facilities.
Large-scale facilities have lower selling prices than small-scale installations. For
example, the original purchase price for solar power generation of less than 10 kW
was 42 JPY/kWh, whereas the purchase price for solar power generation of 10 kW or
more was 40 JPY/kWh. With the generation of tens of billions of kWh of solar
power annually and a purchase period of 20 years, it is possible to avoid enormous
costs by introducing large-scale solar power generation. However, if the amount of
0.01MW 0.01-0.04MW 0.04-1MW
1-10MW
>10MW
kW
12,000,000
10,000,000
8,000,000
6,000,000
4,000,000
2,000,000
0
rooftop
ground
Fig. 21.9 Amount of certified solar power generation in Germany in 2014. (Source: German New
Energy Agency 2017)
5 When installing rooftop photovoltaic panels, an area of 5–10 m
2 is required per 1 kW.
404
W. Zhou et al.
the setting of fixed purchase prices in Japan. The purchase price of solar power
generation is high and differentiated at two scales: less than 10 kW and more than
10 kW. However, as the scale of installation increases, the average cost of solar
power generation tends to decrease, yet the purchase price is set at the same level.
Thus, introduction of large-scale equipment leads to higher profits than for smallscale facilities, so large-scale solar power generation becomes more popular.
When a facility reaches 50 kW, an enormous amount of additional cost is
involved, so the number of installations drops after 50 kW and increases again for
much larger facilities. In order to promote local production for local consumption,
rooftop space should be better utilized (especially in large cities with high power
demand)
5 than under the current system.
In Germany, small- to medium-sized (>0.01 and <0.04 MW) rooftop installations have the highest total capacity (Fig. 21.9). Overall, equipment with a capacity
of 1 MW or less accounts for 74% of the total. By installation type, rooftop solar
power generation facilities account for 73%. Purchase price is subdivided according
to the five scales and installation configurations (rooftop and ground) shown in
Fig. 21.9. The smaller the scale, and the higher the purchase price for rooftop
installation, the larger the amount of small-scale, rooftop solar power generation
installed.
There are merits to introducing mainly large-scale power generation facilities.
Large-scale facilities have lower selling prices than small-scale installations. For
example, the original purchase price for solar power generation of less than 10 kW
was 42 JPY/kWh, whereas the purchase price for solar power generation of 10 kW or
more was 40 JPY/kWh. With the generation of tens of billions of kWh of solar
power annually and a purchase period of 20 years, it is possible to avoid enormous
costs by introducing large-scale solar power generation. However, if the amount of
0.01MW 0.01-0.04MW 0.04-1MW
1-10MW
>10MW
kW
12,000,000
10,000,000
8,000,000
6,000,000
4,000,000
2,000,000
0
rooftop
ground
Fig. 21.9 Amount of certified solar power generation in Germany in 2014. (Source: German New
Energy Agency 2017)
5 When installing rooftop photovoltaic panels, an area of 5–10 m
2 is required per 1 kW.
404
W. Zhou et al.