Recently, increasing urban temperatures due to the Urban Heat Island (UHI) effect and Global Warming (GW) have been remarkable in some Japanese metropolises. The UHI effect and GW not only cause temperatures to rise, they also have other diverse impacts on urban dwellers. Therefore, it is important to understand the effect of temperature increase on urban dwellers to take action for preventing the occurrence of adverse impact. So, this research evaluated the temperature sensitivity in electric power supply. As for the target area, we set the whole of system power supply area and individual supply districts of mainly dominant land usage for office, commercial and residential. Temperature sensitivity for system was positioned as a standard and we compared between system and each district. In addition, the secular change of office and residential districts was examined.
The results of this research are described below.
1) As a result of calculating the temperature sensitivity by time for electric power supply for districts with different building using, only the daytime working hours are affected in the office district, whereas, it showed high figures at the morning and at nighttime in the residential distinct, also the figure gradually increased from morning to afternoon in the commercial district, and showed a remarkably high figure at night, especially at around 8PM.
2) In secular change of long-term of temperature sensitivity, focusing on the comparison between 2001 and 2015, temperature sensitivity decreases greatly in both the summer and winter in the office district, whereas in the residential district, the results that greatly increase in winter especially indicated. It is expected temperature sensitivity will decrease as a result of progress in energy saving measures, but temperature sensitivity increased because increasing in electricity share on thermal demand affected.
3) In secular change of short-term of temperature sensitivity, focusing on comparison between 2010 and 2011, temperature sensitivity in the office and commercial districts decreases greatly during the summer and winter, and the decrease continues until 2015. But the residential district, decrease can be seen only in the summer of 2011.
4) The results of estimating the annual air conditioning use time on each building using showed that the cooling use time was remarkably long in the office and commercial using, and that the period without air conditioning was remarkably long in residential using.
5) As a result of calculating the fluctuation of power consumption in each time when the temperature rose by 1 °C as a whole for Osaka Prefecture, the summer showed a peak around 8PM due to the influence of residential and commercial using. Its figure was about 750 MW. Peak was observed in the morning in addition to the nighttime in winter, but overall the fluctuation was a relatively small figure compared with the summer.
6) As a result of calculating the change amount in annual electricity consumption when the temperature rose by 1 °C as a whole for Osaka prefecture, the increase in the summer greatly exceeded the decrease in the winter in regard to office and commercial using, but compared with 2001, the budget tended to decrease in 2015. Regarding residential using as well, the increase in summer greatly exceeded the decrease in winter, but the decrease in winter remarkably increased in 2015, so the budget was almost balanced.
7) Rate of temperature sensitivity in the system power is relatively low temperature sensitivity because it contains a lot of industrial use where the temperature sensitivity is low. In contrast with, each supply district in Osaka Prefecture (office, residential, commercial district) showed figures much higher than that.