Bioalcohols, such as bioethanol and biobutanol, are suitable replacements for gasoline, while biodiesel can replace petroleum diesel. Improving biofuel engine performance requires understanding its fundamental combustion properties and the pathways of combustion. This study's contribution is experimentally validated chemical kinetic combustion mechanisms for biobutanol and biodiesel. Fundamental combustion data and chemical kinetic mechanisms are presented and discussed to improve our understanding of biofuel combustion. The net environmental impact of biobutanol (i.e., n-butanol) has not been studied extensively, so this study first assesses the sustainability of n-butanol derived from corn. The results indicate that technical advances in fuel production are required before commercializing biobutanol. The primary contribution of this research is new experimental data and a novel chemical kinetic mechanism for n-butanol combustion. The results indicate that under the given experimental conditions, n-butanol is consumed primarily via abstraction of hydrogen atoms to produce fuel radical molecules, which subsequently decompose to smaller hydrocarbon and oxygenated species. The hydroxyl moiety in n-butanol results in the direct production of the oxygenated species such as butanal, acetaldehyde, and formaldehyde. The formation of these compounds sequesters carbon from forming soot precursors, but they may introduce other adverse environmental and health effects. Biodiesel is a mixture of long chain fatty acid methyl esters derived from fats and oils. This research study presents high quality experimental data for one large fatty acid methyl ester, methyl decanoate, and models its combustion using an improved skeletal mechanism. The results indicate that methyl decanoate is consumed via abstraction of hydrogen atoms to produce fuel radicals, which ultimately lead to the production of alkenes. The ester moiety in methyl decanoate leads to the formation of low molecular weight oxygenated compounds such as carbon monoxide, formaldehyde, and ketene, thereby reducing the production of soot precursors. The study concludes that the oxygenated molecules in biofuels follow similar combustion pathways to the hydrocarbons in petroleum fuels. The oxygenated moiety's ability to sequester carbon from forming soot precursors is highlighted. However, the direct formation of oxygenated hydrocarbons warrants further investigation into the environmental and health impacts of practical biofuel combustion systems.

Bioalcohols, such as bioethanol and biobutanol, are suitable replacements for gasoline, while biodiesel can replace petroleum diesel. Improving biofuel engine performance requires understanding its fundamental combustion properties and the pathways of combustion. This study's contribution is experimentally validated chemical kinetic combustion mechanisms for biobutanol and biodiesel. Fundamental combustion data and chemical kinetic mechanisms are presented and discussed to improve our understanding of biofuel combustion. The net environmental impact of biobutanol (i.e., n-butanol) has not been studied extensively, so this study first assesses the sustainability of n-butanol derived from corn. The results indicate that technical advances in fuel production are required before commercializing biobutanol. The primary contribution of this research is new experimental data and a novel chemical kinetic mechanism for n-butanol combustion. The results indicate that under the given experimental conditions, n-butanol is consumed primarily via abstraction of hydrogen atoms to produce fuel radical molecules, which subsequently decompose to smaller hydrocarbon and oxygenated species. The hydroxyl moiety in n-butanol results in the direct production of the oxygenated species such as butanal, acetaldehyde, and formaldehyde. The formation of these compounds sequesters carbon from forming soot precursors, but they may introduce other adverse environmental and health effects. Biodiesel is a mixture of long chain fatty acid methyl esters derived from fats and oils. This research study presents high quality experimental data for one large fatty acid methyl ester, methyl decanoate, and models its combustion using an improved skeletal mechanism. The results indicate that methyl decanoate is consumed via abstraction of hydrogen atoms to produce fuel radicals, which ultimately lead to the production of alkenes. The ester moiety in methyl decanoate leads to the formation of low molecular weight oxygenated compounds such as carbon monoxide, formaldehyde, and ketene, thereby reducing the production of soot precursors. The study concludes that the oxygenated molecules in biofuels follow similar combustion pathways to the hydrocarbons in petroleum fuels. The oxygenated moiety's ability to sequester carbon from forming soot precursors is highlighted. However, the direct formation of oxygenated hydrocarbons warrants further investigation into the environmental and health impacts of practical biofuel combustion systems.

Master of Arts / Department of Landscape Architecture/Regional and Community Planning / Claude A. Keithley / In these times of high energy costs, dwindling supplies of fossil fuels, and talk of “global warming,” we must decide what we are going to do to with the abundance of wind energy available in Kansas. We can no longer afford to “drift,” not caring about the sources of our electricity, or what we are doing to the planet. We must act now to ensure a bright future for our children. Many wind turbines are being erected across Kansas, and this natural resource of wind energy is one that should be tapped, but only after careful planning. There are many factors to consider regarding wind farms; environmental concerns, economics, impacts on the health and well-being of individuals living near wind farms, and tax implications, to mention only a few. Studies are being completed on these issues, and due consideration must be given prior to construction. There are areas across the state that should be avoided when locating wind farms, and other areas in which wind turbines might be a natural “fit.” It is the latter areas which should be the focus of attention for construction, but again, only after giving careful consideration to the overall effects. Wind energy has become a part of Kansas, but future site selections should be done only after careful planning.

Carbon materials are commonly studied as the electrode material for electrochemical double layer capacitance (EDLC) due to their high surface area. The present work aimed to leverage both EDLC and pseudocapacitance through chemical modification of multi-wall carbon nanotubes (MWCNTs) and onion-like carbon (OLC) with polyoxometalates (POMs) to further enhance the performance of these electrodes. Layer-by-layer (LbL) deposition of two commercially available POMs (PMo12O403- and SiMo12O404-) and three synthesized POMs (PMo11VO404-, PMo10V2O405- and PMo9V3O406-) has been investigated. A single-layer of POMs increased the area specific capacitance by approximately three-times, while superimposing of these POMs into two-layer coatings increased the capacitance by approximately five-times. The morphology and composition of these composite materials were investigated using Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS).

Carbon materials are commonly studied as the electrode material for electrochemical double layer capacitance (EDLC) due to their high surface area. The present work aimed to leverage both EDLC and pseudocapacitance through chemical modification of multi-wall carbon nanotubes (MWCNTs) and onion-like carbon (OLC) with polyoxometalates (POMs) to further enhance the performance of these electrodes. Layer-by-layer (LbL) deposition of two commercially available POMs (PMo12O403- and SiMo12O404-) and three synthesized POMs (PMo11VO404-, PMo10V2O405- and PMo9V3O406-) has been investigated. A single-layer of POMs increased the area specific capacitance by approximately three-times, while superimposing of these POMs into two-layer coatings increased the capacitance by approximately five-times. The morphology and composition of these composite materials were investigated using Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS).

Multijunction solar cells made from a combination of CQDs of differing sizes and thus bandgaps are a promising means by which to increase the energy harvested from the Sun’s broad spectrum. In this dissertation, we first report the systematic engineering of 1.6 eV PbS CQD solar cells, optimal as the front cell responsible for visible wavelength harvesting in tandem photovoltaics. We rationally optimize each of the device’s collecting electrodes—the heterointerface with electron accepting TiO2 and the deep-work-function hole-collecting MoO3 for ohmic contact—for maximum efficiency. Room-temperature processing enables flexible substrates, and permits tandem solar cells that integrate a small-bandgap back cell atop a low thermal-budget larger-bandgap front cell. We report an electrode strategy that enables a depleted heterojunction CQD PV device to be fabricated entirely at room temperature. We develop a two-layer donor-supply electrode (DSE) in which a highly doped, shallow work function layer supplies a high density of free electrons to an ultrathin TiO2 layer via charge-transfer doping. Using the DSE we build all-room-temperature-processed small-bandgap (1 eV) colloidal quantum dot solar cells suitable for use as the back junction in tandem solar cells. We further report in this work the first efficient CQD tandem solar cells. We use a graded recombination layer (GRL) to provide a progression of work functions from the hole-accepting electrode in the bottom cell to the electron-accepting electrode in the top cell. The recombination layers must allow the hole current from one cell to recombine, with high efficiency and low voltage loss, with the electron current from the next cell. We conclude our dissertation by presenting the generalized conditions for design of efficient graded recombination layer solar devices. We demonstrate a family of new GRL designs experimentally and highlight the benefits of the progression of dopings and work functions in the interlayers.

A large Canadian financial services institution (FSI) is planning to develop a web-based application aimed at helping homeowners calculate the financial and environmental impacts of potential energy conserving upgrades to their dwellings. The algorithm for this calculator, the questions to be posed to the homeowners, and how the homeowners can access some of the scientifically-inclined energy-related information is presented. The potential upgrades considered were: furnace efficiency, heat-pump efficiency, programmable thermostats, window-efficiency, building insulation, lighting efficiency, and refrigerator efficiency. The algorithm developed was used to demonstrate that changing just one of the input variables can, in certain cases, have a drastic effect on the resulting output: upgrades with positive net present values (NPV) can drop to negative NPV, and in certain cases CO2 emissions can increase as a result of the upgrade considered. The effect of future changes in fuel prices, and the price levied on CO2 emissions is also demonstrated.

Wind power is being added to the supply mix of numerous jurisdictions, and an increasing level of uncertainties will be the new reality for many system operators. Accurately estimating these uncertainties and properly analyzing their effects will be very important to the reliable operation of the grid. A method is proposed to use historical wind speed, power, and forecast data to estimate the potential future forecast errors. The method uses the weather conditions and ramp events to improve the accuracy of the estimation. A bilevel programming technique is proposed to quantify the effects of the estimated uncertainties. It improves upon existing methods by modeling the transmission network and the re-dispatch of the generators by operators. The technique is tested with multiple systems to illustrate the feasibility of using this technique to alert system operators to potential problems during operation.

A large Canadian financial services institution (FSI) is planning to develop a web-based application aimed at helping homeowners calculate the financial and environmental impacts of potential energy conserving upgrades to their dwellings. The algorithm for this calculator, the questions to be posed to the homeowners, and how the homeowners can access some of the scientifically-inclined energy-related information is presented. The potential upgrades considered were: furnace efficiency, heat-pump efficiency, programmable thermostats, window-efficiency, building insulation, lighting efficiency, and refrigerator efficiency. The algorithm developed was used to demonstrate that changing just one of the input variables can, in certain cases, have a drastic effect on the resulting output: upgrades with positive net present values (NPV) can drop to negative NPV, and in certain cases CO2 emissions can increase as a result of the upgrade considered. The effect of future changes in fuel prices, and the price levied on CO2 emissions is also demonstrated.

Wind power is being added to the supply mix of numerous jurisdictions, and an increasing level of uncertainties will be the new reality for many system operators. Accurately estimating these uncertainties and properly analyzing their effects will be very important to the reliable operation of the grid. A method is proposed to use historical wind speed, power, and forecast data to estimate the potential future forecast errors. The method uses the weather conditions and ramp events to improve the accuracy of the estimation. A bilevel programming technique is proposed to quantify the effects of the estimated uncertainties. It improves upon existing methods by modeling the transmission network and the re-dispatch of the generators by operators. The technique is tested with multiple systems to illustrate the feasibility of using this technique to alert system operators to potential problems during operation.