Can Bio-Ethanol be Regarded as Carbon Neutral? Assessment of the Effect of Reducing Oil Use

The present study examined the efficacy of the use of bio-ethanol as an environmental protection measure by conducting quantitative assessment of the amount of CO2 emitted in its lifecycle, including the process of growing plants used as materials for bio-ethanol production. As a conclusion, it was suggested that the use of bio-ethanol does not reduce CO2 emissions, as it stands now, because a large amount of energy is required to produce it, i.e., bio-ethanol production consumes fossil fuels in a large quantity and emits a massive amount of CO2. Actually, the use of bio-ethanol varieties made from corn or wood as an alternative fuel to gasoline increased CO2 emissions. Furthermore, the production and use of bio-ethanol was less cost-effective than other CO2 reduction measures. This means that, in terms of both its effectiveness and economic efficiency, bio-ethanol would not contribute to promoting Japan's "Biomass Nippon Strategy" and accomplishing its primary goal, the "prevention of global warming".