Much attention is focused on biodiesel fuel (BDF) alternative to diesel oil to mitigate global warming and oil dependence. In Kyoto city, BDF produced from waste food oil is utilized as fuel of refuse trucks and city buses. LCA method was applied to evaluate the utilization system of BDF derived from waste food oil for Kyoto city bus through the lifecycle that covered discharge, collection/transportation, plant construction, BDF production and usage in terms of CO₂, NOx, SOx and energy consumption. We have confirmed that usage stage was dominant and environmental load except NOx was reduced compared to diesel bus system. The largest reduction rate was about 60% for SOx and an advantage of BDF over diesel fuel was demonstrated. Considering BDF burning as carbon-neutral remarkably increased the reduction rate of CO₂ for utilization system of industrial food waste oil. Lifecycle impact assessment indicated that urban air pollution was the key contributor to environmental impact as external cost and the reduction of the external cost due to global warming accounted for over 95% of the total reduction cost by introducing the BDF utilization system.

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Many studies about ethanol production technologies have been reported. However there are few studies about feedstock collection. This paper presents cost of collecting and transporting rice straw. Upon investigation of the contractor, which collects rice straw for feed, the costs of collection and transportation prove to be 20.0 and 6.8¥/kg, respectively. Therefore actual cost of rice straw for feed is 26.8¥/kg. On the other hand, the rice straw cost for ethanol feedstock should be less than 11.8¥/kg. Under the condition of small-scale system that is manual labor and local transportation, the rice straw cost is 8.4¥/kg, so it can fall below target cost. In case of large-scale system, if winter crop that is barley straw or Italian Ryegrass is combined, the target cost will be realized. It is important to construct flexible system using not only rice straw but also winter crop.

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