[in Japanese]

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This study evaluated greenhouse gas emission and energy consumption by producing and importing biodiesel derived from Indonesian palm oil. This study evaluated those environmental load based on the results of investigation which was carried out in oil palm plantation and palm oil mill in Lampung, Indonesia. Greenhouse gas emission was evaluated by considering biomass carbon balance. As a result, greenhouse gas emission by producing, importing and combustion of palm biodiesel was estimated to be 60% of greenhouse gas emission by those of diesel oil. However, it is possible to reduce that greenhouse gas emission by utilization of biomass residue and methane in palm oil mill. On the other hand, energy consumption by producing and importing palm biodiesel was estimated to be approximately 10.4MJ/L. If it replaces all diesel consumption in Japan, approximately 110 thousand ha of new oil palm plantation will be needed.

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We developed the AB-NET (Asia Biomass Network Model) software to evaluate the biomass utilization activities in Asian region. AB-NET consists of the following four models.
Plantation Model; The user can determine the best fertilization method including not only chemical fertilizers but also biomass residue by viewing the results of productivity, energy consumption, CO₂ emission, total cost, and furthermore, flow balance of nutrients.
Agro-Industry Model; This model aims to improve the effective utilization process of biomass energy from plantations in the Agro-Industry. Therefore, the model has functions to show process flow, material and energy consumption of each unit process, and to design an efficient process.
Region model; This model integrates the results by Agro-Industry model and the Plantation model and calculates the effect of biomass residues utilization in order to estimate the amount of greenhouse gas and energy balance.
International Transportation model; This model was developed to compare possible biofuel supply chains and assess the influence of long-distance international biofuel transport especially in the transportation of biomass fuel from tropical plantations.

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This paper discusses how efficiency and equity are treated in the indices for sustainability. Ecological Footprint (EF) is known as an index for strong sustainability, and is widely believed that it focuses on only the physical aspect of land productivity, and does not reflect any social aspects. However, the introduction of a measuring unit, global hectare, has made it possible for EF to take not just only inter-generational but also inter-regional, and hence inter-individual equity into account. Recently, Lenzen et al. (2007) has proposed a way to share environmental responsibility between producers and consumers. The way to deal with efficiency and equity in the index analysis is very important because it will crucially affect the policies that we should apply.

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In this study, the basic concept of “Indicators for EcoTopia Society (IES)” was discussed from the perspective of environmental, economic, social and human aspects by effectively utilized literature review. First, several current sustainability related indexes were collected from many documents and compared, and then the new concept of QoSL (Quality of Sustainable Life) in the IES was presented and compared with the current definition of ‘Sustainability’ and ‘QOL (Quality of Life)’ that were similar concept of QoSL by literature review from environmental policy and economics, social psychology and other related fields. Also the possibility of inclusion of environmental, economic, social and human factors to the IES was discussed. Moreover, the importance of multiple assessments was pointed out through the evaluation results of Ecological Footprint, LCA-GHG and Ecological Rucksack in the case study of Bio-Diesel Fuel made from palm oil and diesel.

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This paper aims at the estimation of the contributions of distributed power systems to CO₂ emission reduction and cost saving concretely by region of Japan. In this paper, we evaluate the contribution of heat pump(HP), cogeneration system(CGS), district heating system (DHC) and their optimal combination to reducing CO₂ emission based on micro-level data using GIS. We picked up Utsunomiya, Sapporo and Okinawa which locate middle, north and south part of Japan. We find a linear relationship between the ratio of commercial building floor area to total building floor area and potential CO₂ reduction rate in case of full option and HP case in spite of the large difference of climate conditions. Assuming that the relationship between density of residential building area and the distance from the center of the city of Utsunomiya holds in other regions, we evaluate the potential CO₂ reduction of the new energy equipments for 950 Japan cities where 18.6% CO₂ emission reduction potential in total is indicated. Although there remain many issues in our study, this provides the bridging method between the micro-level regional energy systems and the macro level potentials on CO₂ emission reduction.

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The energy consumption in urban areas accompanies the anthropogenic heat exhaust, and brings a regional warming represented by urban heat island. Such a warming has not been enough clarified to contribute a further increase of the energy consumption and the carbon dioxide emission by some feedback mechanism, though the research is advanced in Japan. Especially, the sensitivity of energy use on temperature varies on purpose of energy use and depends on the urban structure. In addition, urban warming might cause a decrease of carbon dioxide emission in winter, and the evaluation through year is not easy. Nowadays citizen's attention is attracted in maintaining an excellent urban environment including urban thermal comfort and low-carbon society. Both of them have to be considered enough in urban planning process. However, it is necessary to note the case of trade-off between countermeasures on urban heat island and actions for low-carbon society.

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