Massachusetts Institute of Technology
Life cycle analysis of hybrid poplar trees for cellulosic ethanol
Abstract
dc:description.abstractThe main purpose of this paper is to assess the energy and environmental benefits of cultivating hybrid poplars as a biomass crop for cellulosic ethanol. A "Life Cycle Assessment" (LCA) methodology is used to systematically evaluate the hybrid poplar's energy input and output as well as greenhouse gas (GHG) emissions. The system boundary is divided into three sections, agriculture, transportation, and ethanol processing. In this LCA, only energy from fossil fuels is accounted for, and only energy yield from ethanol yield is considered. Energy demands and associated emissions for all operations are divided equally over the total biomass harvested over a 10 year timeline. Ultimately, the net energy ratio, the amount of clean energy produced over the amount of fossil fuels consumed, and the amount of carbon dioxide emitted during the cultivation process is compared to those of current forms of fuel and other renewable resources. The net energy ratio was calculated to be in the range of 5.82 to 8.55, which was found to be higher than both gasoline and corn ethanol.
Degree
thesis:*- Department dc:contributor.department
- Massachusetts Institute of Technology. Department of Mechanical Engineering
- Grantor dc:publisher
- Massachusetts Institute of Technology
- Year dc:date.issued
- 2007
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Huang, Jessica J
- Advisor dc:contributor.advisor
-
- Yang Shao-Horn.
Subjects
dc:subject × 1Rights
dc:rights- Statement dc:rights
-
- M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.
- Licence dc:rights.uri
- Language dc:language.iso
- eng
Identifiers
dc:identifier.*- Handle dc:identifier.uri
- http://hdl.handle.net/1721.1/40429
- OAI identifier oai:identifier
- oai:dspace.mit.edu:1721.1/40429