Abstract
The purpose of this study is to develop a technology assessment model coupled with impacts of shifting compact city, and to analyze contribution of distributed energy system, such as renewables and cogenerations, on reduction of CO2 emissions through applying to a local city.
In the research, the developed model has been applied to Koriyama city, Fukushima Prefecture. The analysis has been made based on two scenarios, Business as usual (BAU) scenario and compact city scenario. In the compact city scenario, we assumed that residential houses and commercial facilities will be gradually relocated to 13 city cores selected by the city. On the other hand, in the BAU scenario, there is no relocation over the analysis period.
It is found from the result that, in the compact city scenario, 270 kilo-ton of CO2 emissions could be reduced from the BAU scenario, which corresponds to 22.7% of CO2 emissions in the residential and commercial sectors in 2010. The improvement of energy efficiency contributes reduction on 70 ktCO2, and the rest of the reduction (200 ktCO2) comes from installation of distributed energy system in the city. Based on the analysis, it is suggested that future land use change should be included into design of low carbon city scenario as well as assessing the suitability of distributed energy system for the city and region.
Considering current trend in population decrease, many cities will face an issue of relocation and/or redesign of urban structure except for large cities such as Tokyo and Osaka. Under these circumstances, the study shows that shifting compact city might enhance the convenience of residents and companies but also could encouraging further greenhouse gas reductions.
