エタノールは,エネルギーと環境の目標に貢献することができます
Alexander E Farrell1, Richard J Plevin, Brian T Turner
1Energy and Resources Group, University of California, Berkeley, CA 94720-3050, USA. aef@berkeley.edu
Science (New York, N.Y.)
|January 28, 2006
まとめ
燃料エタノールを評価したこの研究では,現在のトウモロコシエタノールはガソリンよりも石油密度が低いが,同様の温室効果ガスの排出量があることがわかりました. 大規模なバイオ燃料の使用は,より良い環境効果のために,先端のセルロース技術を必要とする可能性が高い.
科学分野:
- エネルギー科学 エネルギー科学
- 環境科学 環境科学
- 農業科学 農業科学とは
背景:
- 石油依存を軽減するために,バイオ燃料の使用を増やすことが提案されています.
- 燃料エタノール,特にトウモロコシからの燃料は,重要なバイオ燃料です.
- バイオ燃料生産による環境とエネルギーの影響は,徹底的な評価を必要とします.
研究 の 目的:
- 燃料エタノール生産によるエネルギーバランスと環境への影響を評価する.
- 燃料エタノールの既存の分析を批判的に見直す.
- 現在のバイオ燃料評価方法の限界を特定する.
主な方法:
- 6つの代表的な燃料エタノール分析の評価.
- 以前の研究における方法論的欠陥を特定する (例えば,共産物を無視し,時代遅れのデータを使用する).
- 特定の資源投入のための新しいメトリックの開発.
主要な成果:
- トウモロコシエタノール技術は,ガソリンよりも石油密度が低い.
- トウモロコシエタノールからの温室効果ガスの排出量は,ガソリンに匹敵します.
- ネガティブな純エネルギー結果を持つ以前の研究は欠陥がありました.
結論:
- 現在のトウモロコシエタノール生産は環境上の欠点があります.
- 持続可能な大規模な実施には,セルロースエタノールなどのバイオ燃料技術の重要な進歩が必要である.
- バイオ燃料に関する包括的な環境指標に関するさらなる研究は不可欠です.
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