Publications by authors named "Wallace E Tyner"

Sustainable aviation fuels (SAFs) are expected to play an essential role in achieving the aviation industries' goal of carbon-neutral growth. However, producing biomass-based SAFs may induce changes in global land use and the associated carbon stock. The induced land use change (ILUC) emissions, as a part of the full life-cycle emissions for SAF pathways, will affect whether and to what extent SAFs reduce emissions compared with petroleum-based jet fuels.

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Background: It has been argued that the US biofuel policy is responsible for the land use changes in Malaysia and Indonesia (M&I). In this paper, following a short literature review that highlights the relevant topics and issues, we develop analytical and numerical analyses to evaluate the extent to which production of biofuels in the US alters land use in M&I. The analytical analyses make it clear that market-mediated responses may generate some land use change in M&I due to biofuel production in the US.

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This study assesses the potential economic and environmental impacts that would arise if restrictions on glyphosate use resulted in the world no longer planting genetically modified herbicide tolerant (GM HT) crops. 'First round' impacts are the loss of farm level and aggregate impacts associated with the widespread use of GM HT crops (tolerant to glyphosate). There would be an annual loss of global farm income gains of $6.

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Background: The GTAP model has been used to estimate biofuel policy induced land use changes and consequent GHG emissions for more than a decade. This paper reviews the history of the model and database modifications and improvements that have occurred over that period. In particular, the paper covers in greater detail the move from the 2004 to the 2011 database, and the inclusion of cropland intensification in the modeling structure.

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Given the potential for genetic modification (GM) to impact human health, via food and health mechanisms, a greater understanding of the social acceptance of GM is necessary to facilitate improved health outcomes. This analysis sought to quantify U.S.

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Tourists consider many factors, including health, when choosing travel destinations. The potential for exposure to novel or foreign diseases alone can deter travelers from selecting high-risk locations for disease transmission. The 2015-2016 Zika Virus (ZIKV) outbreak in the Americas and Caribbean prompted the World Health Organization (WHO) to declare a Public Health Emergency of International Concern.

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Background: Alcohol-to-jet (ATJ) is one of the technical feasible biofuel technologies. It produces jet fuel from sugary, starchy, and lignocellulosic biomass, such as sugarcane, corn grain, and switchgrass, via fermentation of sugars to ethanol or other alcohols. This study assesses the ATJ biofuel production pathway for these three biomass feedstocks, and advances existing techno-economic analyses of biofuels in three ways.

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This study quantifies and compares the costs of production for six alternative jet fuel pathways using consistent financial and technical assumptions. Uncertainty was propagated through the analysis using Monte Carlo simulations. The six processes assessed were HEFA, advanced fermentation, Fischer-Tropsch, aqueous phase processing, hydrothermal liquefaction, and fast pyrolysis.

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This study evaluates the economic feasibility and stochastic dominance rank of eight cellulosic biofuel production pathways (including gasification, pyrolysis, liquefaction, and fermentation) under technological and economic uncertainty. A techno-economic assessment based financial analysis is employed to derive net present values and breakeven prices for each pathway. Uncertainty is investigated and incorporated into fuel prices and techno-economic variables: capital cost, conversion technology yield, hydrogen cost, natural gas price and feedstock cost using @Risk, a Palisade Corporation software.

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