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Assessing Potential Environmental Impacts According To Probable Patterns Of Switchgrass Adoption In The Southeastern Us, Benjamin Sharp

All Dissertations

To assess the overall net impact of an emerging technology, life cycle assessment (LCA) must be accompanied by projections of adoption. Diffusion of innovation research provides tools that incorporate economic and social variables to explain and forecast integration of technologies. A switchgrass-to-ethanol case study for the southeastern U.S. is used to demonstrate methods for gauging aggregate environmental effects of an emerging energy technology. Before applying diffusion concepts, breakeven capacities are calculated for land in row crops, hay, pasture and marginal land. Breakeven curves are generated to provide upper bounds to switchgrass adoption over a range of farm-gate prices. The amount …

Direct And Indirect Greenhouse Gas Emissions From Biomass Storage: Implications For Life Cycle Assessment Of Biofuels, Isaac Robert Emery

Open Access Dissertations

Ethanol and other biofuels from cellulosic feedstocks are currently the most promising candidates to replace a large fraction of gasoline consumption in the United States and reduce greenhouse gas emissions. Gaps in current approaches to estimating the net greenhouse gas emissions from second-generation biofuels may lead to underestimation of the carbon intensity of these fuels. Current life cycle assessment models of biofuels do not sufficiently account for biomass losses and emissions associated with the harvest and storage of biomass feedstocks, which can require additional fuel and materials use on the farm as well as reducing the effective yield of a …

Miscanthus Production And Processing In Ireland: An Analysis Of Energy Requirements And Environmental Impacts, Fionnuala Murphy

Fionnuala Murphy

The environmental impact of bioenergy supply systems can be determined using life cycle assessment methodologies. This study focuses on the impact of production of Miscanthus pellets and briquettes, potentially used to satisfy renewable energy requirements in Ireland. The impact categories considered are particularly important when assessing bioenergy systems; global warming potential, acidification potential, eutrophication potential, and energy demand. The scope of the study incorporates Miscanthus cultivation, harvest, processing and transport to a biomass distributor. The aim of the research is to evaluate the effects of changes in keys variables on the overall environmental impacts of the system. The scenarios examined …

Incorporating Natural Hazard Resistance Into The Life Cycle Assessment Framework, Jeffery Plumblee

All Dissertations

Hazard resistant building materials are not adequately represented by current LCA approaches, which do not account for environmental benefits of the avoided losses (e.g. avoided waste, avoided materials for repairs) promised by hazard resistant materials. The goal of this study was to encourage a more complete understanding of materials' environmental impacts by developing a framework to include hazard related damages in LCA.
Catastrophe modeling is a well-developed tool used by the insurance industry to assess the probability of hazard and quantify related impacts. These models were studied to identify required input data as well as the format of output results. …

Biomass Gasification: An Alternative Solution To Animal Waste Management, Hanjing Wu

Department of Biological Systems Engineering: Dissertations and Theses

The overall goal of this research was to evaluate gasification of animal waste as an alternative manure management strategy, from the standpoints of syngas production and biochar application.

To meet the overall objective, the thermogravimetric characteristics of dairy manure, as a thermochemical conversion feedstock, were studied firstly. Then, gasification technology was applied to dairy manure and feedlot manure using a fluidized-bed laboratory-scale gasifier. In addition, biochar derived from the feedlot manure was examined for its effects on nutrient leaching as a soil amendment. Finally, a life cycle assessment was conducted to evaluate greenhouse gas emissions of two feedlot manure management …

Life Cycle Sustainability Assessment Framework For The U.S. Built Environment, Murat Kucukvar

Electronic Theses and Dissertations

The overall goals of this dissertation are to investigate the sustainability of the built environment, holistically, by assessing its Triple Bottom Line (TBL): environmental, economic, and social impacts, as well as propose cost-effective, socially acceptable, and environmentally benign policies using several decision support models. This research is anticipated to transform life cycle assessment (LCA) of the built environment by using a TBL framework, integrated with economic input-output analysis, simulation, and multicriteria optimization tools. The major objectives of the outlined research are to (1) build a system-based TBL sustainability assessment framework for the sustainable built environment, by (a) advancing a national …

Sustainability Assessment Of Wind Energy For Buildings, Mehdi Noori

Electronic Theses and Dissertations

Due to increasing concerns for global climate change, onshore and offshore wind energy technologies have stimulated a tremendous interest worldwide, and are considered as a viable solution to mitigate the environmental impacts related to electricity generation. Although wind energy technologies have been considered as one of the cleanest energy sources, they have a wide range of direct and indirect environmental impacts when the whole supply chain is considered. This study aims to quantify the direct and indirect environmental impacts of onshore and offshore wind power technologies by tracing all of the economy-wide supply chain requirements. To accomplish this goal, we …

Sustainable Energy Production In The United States: Life Cycle Assessment Of Biofuels And Bioenergy, Jiqing Fan

Dissertations, Master's Theses and Master's Reports - Open

The United States of America is making great efforts to transform the renewable and abundant biomass resources into cost-competitive, high-performance biofuels, bioproducts, and biopower. This is the key to increase domestic production of transportation fuels and renewable energy, and reduce greenhouse gas and other pollutant emissions.

This dissertation focuses specifically on assessing the life cycle environmental impacts of biofuels and bioenergy produced from renewable feedstocks, such as lignocellulosic biomass, renewable oils and fats. The first part of the dissertation presents the life cycle greenhouse gas (GHG) emissions and energy demands of renewable diesel (RD) and hydroprocessed jet fuels (HRJ). The …

Nutrients Recycling Strategy For Microalgae-Based Co2 Mitigation System, Xinyi E

Theses and Dissertations--Biosystems and Agricultural Engineering

Coal-fired electricity production is the major emitter of CO₂ and other greenhouse gases including NO_x and SO_x. Microalgae-based CO₂ mitigation systems have been proposed to reduce the net CO₂ emission from coal-fired power plants. This study focused on developing an optimum culture media and exploring the possibilities for recycling nutrients, which were added as commercial mineralized chemicals at the beginning of cultivation.

In order to release the nutrients embedded in the cells so that they can be used as a nutrient source for new cells, Scenedesmus biomass was digested by anaerobic bacteria. Results showed …

Socioeconomic Factors' And Water Source Features' Effect On Household Water Supply Choices In Uganda And The Associated Environmental Impacts, Christine M. Prouty

USF Tampa Graduate Theses and Dissertations

Over the last twenty years or more, Uganda has benefitted from significant strides in water and sanitation initiated by the United Nations' Millennium Development Goals. While the rapid progress towards development has been vastly beneficial, it is also important that it does not occur at the expense of the environment. The environmental impacts of these water sources must be evaluated and understood. However, to develop a robust understanding of the impact requires inclusion of the community members who use these sources and their perceptions of them. Consequently, the goal of this research is to investigate the interrelationships between socioeconomic factors, …