Biofuels are currently derived from corn and soybeans in the US to make ethanol and biodiesel, respectively. While energy and greenhouse gas savings are realized, several significant tradeoffs have arisen including a) increase in food prices and b) a shift in environmental burden to impacts manifesting as eutrophication and hypoxia (i.e. the Dead Zone in the Gulf of Mexico). Cultivating biofuels on marginal lands may alleviate these problems and may serve to contribute additional environmental benefits in the form of soil remediation.
The goal of the proposed research is to quantify the benefits of growing bioenergy crops on marginal lands. Throughout this project they will: (i) quantify on-site phytoremediation of biofuel crops, (ii) evaluate runoff related to biofuel crops, and (iii) compare the life cycle environmental impacts of biofuels grown on marginal lands to petroleum fuels and traditional biofuels (i.e. soy biodiesel, corn ethanol).
The PIs at the University of Pittsburgh will partner with Alcoa Corp and a local nonprofit, GTECH Strategies, to form a unique collaboration. Alcoa Corp is involved in a mine reclamation demonstration at the Mather Mine site in PA. Alcoa is aiding in the evaluation of the use of alkaline clay to assist in reclamation. GTECH Strategies cultivates biofuel crops on vacant urban lands; their mission is to foster community growth in underserved communities through the creation of "egreen collar" jobs.
This project is unique not only for Pennsylvania, but for the water resources, water quality, and biofuels research community at large. The findings of the proposed research will inform the research community about the life cycle environmental benefits of alternative uses for marginal and vacant lands, and will also contribute to the literature and understanding of phytoremediation. The findings of the life cycle assessment will also contribute to the ever growing and highly debated body of LCA research on biofuels.
The proposed activities will have broad reaching impacts that serve the purpose of energy production, storm water management, nutrient management, water conservation, reclamation, and job creation in underserved communities. The impacts of the proposed research extend from contribution to the scientific study of biofuel crops to community engagement and empowerment through the collaboration with GTECH Strategies. The proposed project will directly aid in the increase of job opportunities in environmental justice communities through GTECHs green job corps program and will foster the growth of GTECH as a sustainable nonprofit. Clearly, the development of new strategies for sustainable biofuel production will aid in addressing national security issues and help the nation meet national 2010 fuel standards. In addition to the outreach inherent in the collaboration with GTECH, they also propose to continue to include a diverse set of students (REU, grad, and high school, via GTECH's green job corps) in the proposed research. They also have outlined an extensive plan for integration of the research partnership into the sustainability curriculum at Pitt.
This goal of this research project was to explore several aspects pertaining to the growth of biofuel feedstocks on marginal lands in the US. Biofuels’ sustainability has been questioned because of the food/energy/environment trilemma, thus this research sought to find alternate environmentally sound methods for production of biofuels beyond the traditional use of prime farmland and high-input agricultural practices by cultivating biofuel feedstocks on lands not fit for traditional food-based agriculture. Such land is termed marginal land and includes abandoned mine lands, closed landfills, and Brownfields, which occupy approximately 121 million hectares in the US. One part of this research investigated the use of vacant lots, or urban marginal land, located in cities to cultivate biofuel crops, namely sunflower. Three years of monitoring concentrations of Al, Fe, Zn, Ni, Pb, As, Cd, Cr and Se in soil, analysis of metal contaminants in sunflower plants, and the calculation of the net energy return of the sunflower-to-biofuel system in Pittsburgh were performed. The findings showed that phytoremediation does not take place at a significant level on these types of urban marginal lands (also known as greyfields) and that a positive energy balance can be achieved under current conditions in Pittsburgh when lots larger than 0.2 ha are used and biodiesel is processed locally. A paper was published that summarizes these findings in the journal Landscape and Urban Planning titled "The Viability of Biofuel Production on Urban Marginal Land: An Analysis of Metal Contaminants and Energy Balance for Pittsburgh's Sunflower Gardens" which summarized the findings of in situ phytoremediation studies conducted in Pennsylvania. Another part of this study evaluated the potential to use contaminated abandoned mine lands to cultivate biofuel crops. This study used as a model an approximate 25 hectare abandoned coal mine refuse pile located in Mather, PA known for its severe acid mine drainage, and local ecosystems and watershed deterioration. Results showed that production of sunflower biodiesel feedstock on treated abandoned coal mine land is feasible and environmentally benign when compared to other reclamation processes and other fuel production processes. The analysis employed life cycle assessment (LCA- which quantifies the environmental impacts of biofuels on marginal lands from raw materials extraction through use of biofuels) showed that production of biodiesel from sunflower grown on abandoned mine lands’ environmental impact is significantly lower than complete or typical land reclamation processes and only marginally larger than production of biodiesel from soybean grown on prime farmland. These results show that production of biofuel feedstocks on marginal land can be a feasible and sustainable activity. A paper detailing the LCA of this research on biofuel feedstock production on marginal lands is under review at the Journal of Cleaner production. This research also conducted "Geographic Information Systems (GIS) to Assess Potential Biofuel Crop Production on Urban Marginal Lands" (which is also the title of a paper published in Applied Energy). Essentially, GIS was used to identify what land and how much land -- from vacant urban lands to marginal lands across the US -- could be used to cultivate biofuel crops. This research combined soil classification data with urban development data to develop a GIS framework to determine the amount of urban marginal land available in Pittsburgh, Pennsylvania. A second geographic information systems study was completed which analyzed five renewable energy resources’ (i.e. soybeans, sunflowers, and algae for biodiesel, and solar and wind for electricity) potential for energy production on marginal lands for the US and is in progress for the journal Renewable and Sustainable Energy Reviews. The study found that the five renewable energy sources could contribute up to 70% of the total energy demand for diesel and electricity in the US. Ultimately, this research has shown that biofuel production on marginal lands in the US is a viable solution to the food/energy/environment dilemma that we currently face. This Project Outcomes Report for the General Public is displayed verbatim as submitted by the Principal Investigator (PI) for this award. Any opinions, findings, and conclusions or recommendations expressed in this Report are those of the PI and do not necessarily reflect the views of the National Science Foundation; NSF has not approved or endorsed its content.
