Biotechnology Letters

, Volume 34, Issue 12, pp 2259–2263 | Cite as

Energy consumption and greenhouse gas emissions from enzyme and yeast manufacture for corn and cellulosic ethanol production

  • Jennifer B. Dunn
  • Steffen Mueller
  • Michael Wang
  • Jeongwoo Han
Original Research Paper

Abstract

Enzymes and yeast are important ingredients in the production of ethanol, yet the energy consumption and emissions associated with their production are often excluded from life-cycle analyses of ethanol. We provide new estimates for the energy consumed and greenhouse gases (GHGs) emitted during enzyme and yeast manufacture, including contributions from key ingredients such as starch, glucose, and molasses. We incorporated these data into Argonne National Laboratory’s Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation model and observed that enzymes and yeast together contribute 1.4 and 27 % of farm-to-pump GHG emissions for corn and cellulosic ethanol, respectively. Over the course of the entire corn ethanol life cycle, yeast and enzymes contribute a negligible amount of GHG emissions, but increase GHG emissions from the cellulosic ethanol life cycle by 5.6 g CO2e/MJ.

Keywords

Enzymes Ethanol Life-cycle analysis Yeast 

Supplementary material

10529_2012_1057_MOESM1_ESM.docx (329 kb)
Supplementary material 1 (DOCX 329 kb)

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Copyright information

© Springer Science+Business Media Dordrecht (outside the USA) 2012

Authors and Affiliations

  • Jennifer B. Dunn
    • 1
  • Steffen Mueller
    • 2
  • Michael Wang
    • 1
  • Jeongwoo Han
    • 1
  1. 1.Argonne National LaboratoryCenter for Transportation ResearchArgonneUSA
  2. 2.Energy Resources CenterUniversity of Illinois at ChicagoChicagoUSA

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