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Sustainable Built Environments Senior Capstone / Climate change is gaining speed and affecting the life on earth in increasingly drastic ways. Humans are the main cause for climate change with the primary driver being amplified greenhouse gases in the atmosphere. Burning of fossil fuels and deforestation are the largest contributors of greenhouse gases, and both are done for human needs and comfort. A major source of greenhouse gases is the energy used to run buildings. Specifically, heating, cooling, and lighting are the largest users of electric; therefore, the largest contributors to climate change. This report takes an in depth look at building energy uses, how the energy used for these systems can be reduced, and how much carbon emissions can be cut by implementing appropriate design strategies and using proper materials for the climate. Computer programs COMcheck and eQUEST were used to analyze building energy performance and analyze the effect of alternate energy strategies. The results show that minimal modifications at the design stage of planning a building can decrease energy needs by up to 45% by passively using the environment as a power source. The results also display that using sensible materials can have a big impact on the long-term carbon emissions of a building. The analysis for this report was designed specifically for commercial buildings; therefore, future research would include the carbon emission analysis for residential buildings.

This thesis describes the development of a new type of sensor for nitric oxide (NO) that can be used in a variety of combustion diagnostics and control applications. The sensor utilizes the absorption of ultraviolet (UV) radiation by the NO molecule to determine the concentration via optical absorption spectroscopy. UV radiation at 226.8 nm is generated by sum frequency mixing the outputs from a 395-nm external cavity diode laser (ECDL) and a 532-nm diode-pumped, intracavity frequency doubled Nd:YAG laser in a beta-barium borate (BBO) crystal. This radiation is used to probe the (v'=0, v"=0) band of the Α*Σ+ - Χ*π electronic transition of NO. The ECDL is tuned so that the UV radiation is in resonance with a specific energy level transition, and it is then scanned across the transition to produce a fully resolved absorption spectrum. Preliminary experiments were performed in a room-temperature gas cell in the laboratory to determine the accuracy of the sensor. Results from these experiments indicated excellent agreement between theoretical and experimental absorption line shapes as well as NO concentrations. Further experiments were performed at two actual combustion facilities to demonstrate the operation of the sensors in realistic combustion environments. Tests on a gas turbine auxiliary power unit (APU) at Honeywell Engines and Systems and on a well-stirred reactor (WSR) at Wright-Patterson Air Force Base produced excellent results despite the harsh temperatures and vibrations present. Overall, the sensitivity was estimated to be 0.8 parts per million (ppm) of NO (at 1000 K) for a 1 meter path length and the measurement uncertainty was estimated to be ±10%.

Currently, four areas of Texas have been designated by the United States Environmental Protection Agency (EPA) as non-attainment areas because they exceeded the national one-hour ground-level ozone standard of 0.12 parts-per-million (ppm). Ozone is formed in the atmosphere by the reaction of Volatile Organic Compounds (VOCs) and Nitrogen Oxides (NOx) in the presence of heat and sunlight. In May 2002, The Texas State Legislature passed Senate Bill 5, the Texas Emissions Reduction Plan (TERP), to reduce the emissions of NOx by several sources. As part of the 2001 building energy performance standards program which is one of the programs in the TERP, the Texas Legislature established the 2000 International Energy Conservation Code (IECC) as the state energy code. Since September 1, 2001, the 2000 IECC has been required for newly constructed single and multifamily houses in Texas. Therefore, this study develops and applies portions of a methodology to calculate the energy savings and NOx emissions reductions from the adoption of the 2000 IECC to new single family houses in non-attainment and affected counties in Texas. To accomplish the objectives of the research, six major tasks were developed: 1) baseline data collection, 2) development of the 2000 IECC standard building simulation, 3) projection of the number of building permits in 2002, 4) comparison of energy simulations, 5) validation and, 6) NOx emissions reduction calculations. To begin, the 1999 standard residential building characteristics which are the baseline construction data were collected, and the 2000 IECC standard building characteristics were reviewed. Next, the annual and peak-day energy savings were calculated using the DOE-2 building energy simulation program. The building characteristics and the energy savings were then crosschecked using the data from previous studies, a site visit survey, and utility billing analysis. In this thesis, several case study houses are used to demonstrate the validation procedure. Finally, the calculated electricity savings (MWh/yr) were then converted into the NOx emissions reductions (tons/yr) using the EPA's eGRID database. The results of the peak-day electricity savings and NOx emissions reductions using this procedure are approximately twice the average day electricity savings and NOx emissions reductions.

This thesis consists of three essays. The first essay, "Press and Leaks: Do Newspapers Reduce Toxic Emissions?", uses data on plant-level emissions in 2001-2009 from the Toxic Release Inventory of the US Environmental Protection Agency, coupled with data on location and content of newspapers, to investigate whether media coverage induces firms to reduce toxic emissions. The results show that an increase in Newspapers Density, that is the number of newspapers nearby the plant, raises the press coverage of the plant's toxic emissions and reduces the amount of these emissions. This association is larger in industries exposed to consumer pressure and in counties subjected to extreme negative health outcomes. The second essay, "Gender Quotas, Female Politicians and Public Expenditures: Quasi-Experimental Evidence", estimates the effect of gender quotas on the election of female politicians and on public finance decisions in Spanish municipalities, using a Before-After Regression Discontinuity Design. Gender quotas have increased the percentage of female candidates and also, but to a lower extent, the percentage of female councilors. The difference between the two effects is due to the strategic positioning of candidates within lists. The effect of quotas on the election of female mayors and on the size and composition of municipal expenditures is not statistically different from zero. The third essay, "Are attitudes endogenous to political regimes? Beliefs about working women in state-socialist countries", studies whether individual beliefs about gender roles are endogenous to political regimes, using a Difference-in-Differences analysis. The results suggest a significant difference in the evolution of attitudes towards gender roles between Europeans in state-socialist countries and other Europeans during the period 1947-1991. Central and Eastern Europeans who formed their attitudes during state socialism seem more likely to hold progressive beliefs regarding working women.

This thesis pertains to development of preliminary combustor design tools for prediction of NOx emissions from aircraft gas turbine combustors. These tools are developed in the form of chemical reactor models and their objective is to predict the formation of NOx based on combustor geometry and engine input parameters such as inlet pressure, inlet temperature, fuel flow and air flow. The construction of the reactor networks follow from cold flow computational fluid dynamics results as it provides a way for allocating volumes to each reactor in the network. The ability of the model to predict NOx has been analysed by comparing predictions with measured data and theoretical trends. The model predictions for different combustors satisfy theoretical trends across various thrust levels in that the model correctly captures the effect of various input parameters on NOx formation and predicts most power conditions for various combustors within 15% of the measured value.

Biogas as a fuel is attractive from a greenhouse standpoint, since biogas is carbon neutral. To be used as such, increasingly stringent emission standards must be met. Current low-emission technologies meet said standards by precisely controlling the air-fuel ratio. Biogas composition can vary substantially, making air-fuel ratio control difficult. This research was conducted as part of a larger project to develop a sensor that accurately measures biogas composition. Biogas was simulated by fuel mixtures consisting of natural gas and CO2; the effects that fuel composition has on emissions and catalyst performance were investigated. Engine-out THC and NOx increased and decreased, respectively, with increasing CO2 in the fuel mixture. Doubling the catalyst residence time doubled the conversion of THC and CO emissions. The effectiveness of the catalyst at converting THC emissions was found to be dependent on the relative proportions of engine-out THC, NOx and CO emissions.

This thesis pertains to development of preliminary combustor design tools for prediction of NOx emissions from aircraft gas turbine combustors. These tools are developed in the form of chemical reactor models and their objective is to predict the formation of NOx based on combustor geometry and engine input parameters such as inlet pressure, inlet temperature, fuel flow and air flow. The construction of the reactor networks follow from cold flow computational fluid dynamics results as it provides a way for allocating volumes to each reactor in the network. The ability of the model to predict NOx has been analysed by comparing predictions with measured data and theoretical trends. The model predictions for different combustors satisfy theoretical trends across various thrust levels in that the model correctly captures the effect of various input parameters on NOx formation and predicts most power conditions for various combustors within 15% of the measured value.

Biogas as a fuel is attractive from a greenhouse standpoint, since biogas is carbon neutral. To be used as such, increasingly stringent emission standards must be met. Current low-emission technologies meet said standards by precisely controlling the air-fuel ratio. Biogas composition can vary substantially, making air-fuel ratio control difficult. This research was conducted as part of a larger project to develop a sensor that accurately measures biogas composition. Biogas was simulated by fuel mixtures consisting of natural gas and CO2; the effects that fuel composition has on emissions and catalyst performance were investigated. Engine-out THC and NOx increased and decreased, respectively, with increasing CO2 in the fuel mixture. Doubling the catalyst residence time doubled the conversion of THC and CO emissions. The effectiveness of the catalyst at converting THC emissions was found to be dependent on the relative proportions of engine-out THC, NOx and CO emissions.

Traditional measures used in the composting industry for ammonia and odor emissions control are those involving collection and treatment such as thermal oxidation, adsorption, wet scrubbing and biofiltration. However, these methods do not address the source of the odor generation problem. The primary objective of this thesis research was to develop preventive means to minimize ammonia and odor emissions, and maximize nitrogen conservation to increase the agronomic value of compost. Laboratory-scale experiments were performed to examine the effectiveness of various technologies to minimize these emissions during the active phase of composting. These techniques included precipitating ammonium into struvite in composting matrix before it release to outside environment; the use of chemical and biological additives in the form of yeast, zeolite and alum; and the manipulation of key operational parameters during the composting process. The fact that struvite crystals were formed in manure composting media, as verified by both XRD and SEM-EDS analyses, represents novel findings from this study. This technique was able to reduce ammonia emission by 40-84%, while nitrogen content in the finished compost was increased by 37-105%. The application of yeast and zeolite with dosages of 5-10% enhanced the thermal performance of composting and the degree of degradation, and ammonia emission was reduced by up to 50%. Alum was found to be the most effective additive for both ammonia and odor emission control; ammonia emission decreased by 45-90% depending on the dosage, and odor emission assessed via an dynamic dilution olfactometer was reduced by 44% with dosages above 2.5%. This study reaffirmed that aeration is the most influential factor to odor emission. An optimal airflow rate for odor control would be 0.6 L/min.kg dry matter with an intermittent aeration system. Quantitative relationships between odor emission and key operational parameters were determined, which would enable “best management practices” to be devised and implemented for composting. An empirical odor predictive model was developed to provide a simple and direct means for simulation of composting odor emissions. The effects of operating conditions were incorporated into the model with multiplicative algorithm and linearization approximation approach. The model was validated with experimental observations.