抄録
Selected social-and electricity-saving-benefits are compared for two timechange alternatives to the existing (fixed) national time in Japan. The alternatives are: 1) daylight savings time (DST), and 2) a permanent onehour change plus DST. The purpose is to quantify passive means that can be used to better match available daylight with current living and working patterns. Three longstanding objections against DST are reviewed while potentials for improving the quality of sleep and limiting peak electricity use are advanced.
Documented records are used to evaluate the three longstanding objec-tions in the current context. These objections concern agriculture, safety for school children, and weekday evening leisure activities. Current literature meanwhile is used to support the argument for better quality sleep, especially for urban dwellers. Lastly, peak electric lighting and cooling load reductions are estimated for a prototypical office building.
It is concluded that the longstanding arguments against DST can be refuted. The benefits to improved sleep meanwhile are hypothesized but remain unproven. For the office building, it is shown that DST alone, but even moreso a two-hour delay, can effectively displace the growing sum-mer peak demand for electricity while providing available daylight later into the evening. For either case, DST would fit most neatly between the spring and fall equinox holidays, providing time for adaptation as well as celebration. Significant social and economic benefits meanwhile could be realized throughout Japan.
