Browsing by Author "Tiffany, Douglas"

Now showing 1 - 7 of 7
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    Cash Rent: How much in 1983; Crop Share Rent: Is Our Lease Fair?
    (University of Minnesota Extension Service, 1983-04) Hasbargen, Paul R.; Thomas, Kenneth; Tiffany, Douglas
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    Distillate Usage Patterns in Minnesota: Development of Data and Tools To Analyze Policies Affecting Biodiesel Usage
    (2005-01-01) Tiffany, Douglas
    Biodiesel is a renewable fuel derived from vegetable oils or animal fats that can substitute for diesel fuel in engines or fuel oil in furnaces. Biodiesel is produced by the process of transesterification, a simple chemical process that breaks individual triglyceride molecules into three molecules of methyl esters consisting of long chain fatty acids, similar to diesel derived from petroleum. Biodiesel has proven lubricity benefits at low blends, which will be important when sulfur levels are reduced in the U.S. supply of diesel in 2006. In addition, blends of biodiesel and its usage in a pure form reduce particulate matter (PM), volatile organic compounds (VOC), as well as other toxic gases and Greenhouse Gases (GHG). Reduced emissions from biodiesel blends result from its zero sulfur content and higher oxygen content versus petro-diesel. Federal standards established by the U.S. Environmental Protection Agency (EPA) may force local authorities to implement a variety of policies to reduce VOC's, one of the precursors of ground level ozone formation, and other toxic emissions. There is also substantial concern among public health professionals concerning the formation of particulate matter (PM) from diesel engines, especially when originating from school buses, transit buses, and diesel-powered electrical generators.
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    Economic analysis : co-generation using wind and biodiesel-powered generators
    (2005-10) Tiffany, Douglas
    This study was undertaken to determine the economic feasibility of complementing electricity generated by wind with electricity generated by diesel gensets using various blends of biodiesel. An investment model was developed to estimate whether adding a genset, which increases the investment, revenue and operating costs will enhance the economic viability of generating electricity with a wind turbine. The investment model provides a tool that can be used to answer this question for sites with various wind characteristics and with alternative sources of revenue.
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    Energy and chemicals from native grasses : production, transportation, and processing technologies considered in the Northern Great Plains
    (2006-06) Tiffany, Douglas; Jordan, Brendan; Dietrich, Erin; Vargo-Daggett, Becca
    Production of biomass from native prairie species offers the opportunity to produce energy and chemicals while providing substantial ecological services in the Northern Great Plains. This paper analyzes the application of rapid pyrolysis to produce biooil, which has the potential for use as a low-grade fuel oil or as a source for extraction of valuable chemicals. Yields of bio-oil, the quantities of extractable chemicals, and chemical prices drive the economics of this concept, which has a more extensive track record utilizing wood chips. A spreadsheet model was developed to determine gross margins available to defray costs to extract and refine such chemical products as hydroxyacetaldehyde, phenol, formic acid, acetic acid and various resins. Although efforts to hydrolyze anhydroglucose were successful, efforts to produce ethanol from the resulting six-carbon sugars were unsuccessful in a related trial. To understand the overall project economics, it was necessary to consider the availability and productivity of lands in the Northern Great Plains that can provide low cost native prairie grasses including Big Bluestem and Switchgrass. Production economics and transportation economics were analyzed to determine the costs of native prairie grasses delivered to a plant capable of pyrolyzing the biomass. Competing technologies that could also use native prairie grasses are considered as well as policy alternatives important for production of energy and chemicals from native prairie grasses.
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    Factors associated with success of fuel ethanol producers
    (2003-08) Tiffany, Douglas; Eidman, Vernon R.
    Economic factors associated with success or failure of dry-mill ethanol plants utilizing corn as a feedstock are analyzed and discussed. A spreadsheet model is used to conduct the analysis based on the assumptions and interactions of various factors. Plant managers and bankers were interviewed in the process of establishing baseline conditions of operation including capital cost per gallon of capacity, ethanol yield per bushel of corn ground, percentage of debt capital, operating expenses of natural gas, electricity, enzymes, chemicals, repairs, labor, and management. Sensitivities were determined and graphed to demonstrate the respective influence of corn price, ethanol price, natural gas price, ethanol yield, capacity factor, and interest rate-debt percent interactions. The model was used to predict the financial performance of a modern, well-sized, dry-mill plants if the prices that occurred over the past decade with respect to corn prices, ethanol prices, prices of DDGS and CO2, natural gas prices, and interest rates were to re-play. Rates of returns on equity of dry-mill ethanol plants were compared to rates compiled in the last decade for a group of 200 farmers in southwestern Minnesota. Patterns of loan repayment, influence of technological changes, and the role of government subsidies are discussed.
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    Roll Press Compaction of Corn Stover and Perennial Grasses
    (2011-11) Kaliyan, Nalladurai; Morey, Vance; Schmidt, David; Tiffany, Douglas
    Increasing the bulk density of biomass materials to at least 240 kg/m3 (15 lb/ft3) is important for efficient handling and truck transport from the field to an end user. Roll press compaction increased the bulk density of coarsely ground biomass materials to 265 to 365 kg/m3 (16 to 23 lb/ft3).
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    Where Does Minnesota's Grain Crop Go? An Analysis of Minnesota's Elevator Grain Shipments for the Period, 7/99-6/00
    (2002-02-01) Fruin, Jerry; Tiffany, Douglas
    This study describes the movement of grain shipments from Minnesota to their final destinations. A sample of approximately 100 (or 20 percent) of Minnesota's grain elevators reported their monthly grain shipments by mode to each of nine destinations from July 1999 to June 2000. The researchers used this data to project grain shipments from Minnesota and each of six crop reporting districts by grain and by transportation mode to final destination. Minneapolis and Mississippi River ports were the most important destinations, receiving 28.4 percent of all shipments. Pacific Northwest export ports received 17.9 percent. Minnesota-based corn, soybean, and wheat processors received 16.6 percent of shipments. Duluth-Superior received 10.5 percent and Mexico received 7 percent. Rail was used for 494 million bushels (14.1 million tons) or 64 percent of all grains. Rail shipments of 50 or more cars accounted for 47 percent of all elevator shipments. Both destination and modal percentages varied substantially by grain and by crop report.