Distributed Cellulosic Ethanol: A County Level Investigation of Sustainable Production Potential
Open Access
- Author:
- Welch, Amy P
- Graduate Program:
- Geography
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- None
- Committee Members:
- Amy Glasmeier, Thesis Advisor/Co-Advisor
- Keywords:
- renewable energy
calculator
sustainability
biofuel
biomass - Abstract:
- Development of ethanol from cellulosic biomass may present significant opportunities for areas and regions not currently engaged in starch based ethanol production. The diversity in potential feedstocks for this second generation, bio-based ethanol may enable communities with significant wood based resources, biogenic wastes and agricultural residues to enter into this growing industry. Though there has been numerous efforts to characterize the nation’s cellulosic ethanol production potential, there is little information available for local communities to gauge local resource availability for fuel production. Furthermore, there have not been significant investigations into sustainable cellulosic fuel production at a local level based upon local site characteristics. This study developed a methodology for assessing cellulosic resource potential at a local level through spatial analysis of current land use patterns and agricultural practices, application of sustainability criteria based upon local conditions, and a biofuel calculator designed to accommodate this data. Five cellulosic resource categories were considered during this study and the process for determining local fuel production potential were illustrated with a case study of Centre County, Pennsylvania. Land based resources for which spatial analysis was performed included: 1) forest products; 2) agricultural residues; and 3) dedicated energy crops. Non-land based feedstocks were also considered and included: 1) primary wood industry waste; and 2) secondary wood products manufacturing waste. ArcGIS technology, current land use and land cover maps for the Commonwealth of Pennsylvania and Natural Resources Conservation Service soil maps were used to determine the total harvestable area for forest and agricultural feedstocks. Sustainability criteria based upon soil types, associated harvesting limitations and proximity to riparian areas were applied to the total land area within each of the land cover categories considered, effectively reducing the total harvestable area for cellulosic ethanol feedstock collection. Two levels of sustainability (low and high) were calculated, and differed in the level of protection applied to riparian areas as well as in the removal rates of biomass material from forest and agricultural ecosystems. A cellulosic biomass total from all five resource categories was ultimately converted into a local ethanol fuel potential and compared against local fuel demand to asses the degree to which local cellulosic resources might offset local fuel demand. The case study of Centre County, PA demonstrated that ethanol production potentials increased from a level capable of meeting just under 10 percent of the county’s fuel demand under the high sustainability scenario encompassing only forested land within 50 meters of roads up to a maximum of over 25 percent of consumption for the low sustainability scenario encompassing all harvestable forestland in the county. This thesis and calculator show that, though local biofuel potential can not fully meet total liquid fuel demand for the study site with the sustainability criteria applied in this calculator, there is a considerable resource potential present. Economic development opportunities may be realized through the sustainable collection local cellulosic resources and the production of a value added product such as ethanol. Through the creation of a calculator, this study provides a tool for local communities to better understand local resource collection potential under a sustainably paradigm for liquid fuel production. The biofuel calculator is a flexible tool which can be easily updated to keep pace with new technological specifications for the ethanol industry, as well as potential changes in biomass yields, consumption rates and land use patterns at the study site level. Moreover, the calculator may be used as a comparative analysis tool for local, regional or other scaled applications.