Nutrient runoff from excess land application of poultry litter in the Chesapeake Bay Watershed has caused damage to the Chesapeake Bay and lead to the need for alternative poultry litter disposal methods. This study provided an economic feasibility analysis of the use of poultry litter as a partial replacement of coal at an electrical generating unit in Virginia's Chesapeake Bay Watershed. Previous research on the feasibility of converting litter to energy failed to include uncertainty in benefit-cost variables, therefore, this study used risk analysis to incorporate variable uncertainty. Project net worth in previous studies was measured under a public investment scenario with risk neutral preferences but did not take into account risk averse preferences common in private investment. This paper compared benefits under both public risk neutral and private risk averse investor preferences. NPV results showed the proposed project to be feasible but sensitive to the acquisition cost of poultry litter, the unit ash value of litter, and future coal price projections. The maximum level of risk aversion required for feasibility increased when expected returns were measured on an investment scale compared to an annual income scale. Poultry litter combustion produced lower levels of NOx and SO₂ emissions compared to coal, therefore, emission allowance trading through the EPA market based trading programs generated additional benefits to the model and increased the maximum level of risk aversion permitted for feasibility. Results suggested the potential to dispose of 110 thousand tons of poultry litter per year from the Chesapeake Bay Watershed without violating EPA emission standards. / Master of Science

Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2017-01-13T13:09:46Z No. of bitstreams: 2 Dissertação - Laura Vitória Rezende Dias - 2016.pdf: 6797582 bytes, checksum: 102b4a133abc8e93649bbe49a562dcad (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-01-16T11:03:49Z (GMT) No. of bitstreams: 2 Dissertação - Laura Vitória Rezende Dias - 2016.pdf: 6797582 bytes, checksum: 102b4a133abc8e93649bbe49a562dcad (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-01-16T11:03:49Z (GMT). No. of bitstreams: 2 Dissertação - Laura Vitória Rezende Dias - 2016.pdf: 6797582 bytes, checksum: 102b4a133abc8e93649bbe49a562dcad (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-12-05 / This work is the development of a prototype for Stirling engine which was designed with the aim of understanding the machine mainly about the component parts, construction difficulties and type of relevant parameters for its performance. Starting from geometric and thermodynamic data from the prototype, with application of the Schmidt modeling, a digital program was developed to calculate values such as power output and efficiency. The prototype was also used to carryd out bench tests using a data acquisition system implemented in electronics platform Arduino Uno. Using Hall-effect and temperature sensors, following the steps of the algorithm proposed by Conner, it was possible to raise data as temperature and revolutions per minute (rpm) for the flywheel coupled to the prototype shaft, these variables made possible to estimate the power output and operational conditions such as the gas temperature in compression and expansion spaces, etc. The comparison between results from simulations and the bench tests demonstrated the great influence of prototype construction data (volumes, source temperature, etc.) on the output power and the performance of the equipment and also how far is the constructed device from the ideal model proposed by Schmidt. The experiments have shown that the prototype can reach a rotation speed up to 1.200 rpm at 159 degrees Celsius of external engine heat source, with output power of 100 milliwatt. The prototype resulting from this research, although small, has allowed the access to important information that can open paths to the construction of larger Stirling engines and consequently with output powers closer to practical use. / Este trabalho consiste no desenvolvimento de um protótipo didático de motor Stirling, que foi concebido com o intuito de compreender a máquina principalmente em relação as partes componentes, as dificuldades construtivas e os tipos de parâmetros relevantes para o desempenho. Partindo de dados geométricos e termodinâmicos do protótipo, com aplicação da modelagem de Schmidt, elaborou-se um programa digital que permite calcular grandezas como potência de saída e rendimento. Empregando o protótipo, foram também realizados ensaios em bancada de laboratório, para os quais utilizou-se um sistema de aquisição de dados implementado na plataforma eletrônica Arduino Uno. Através do uso de sensores de efeito Hall e de temperatura, seguindo os passos do algoritmo proposto por Conner, foi possível levantar dados como temperatura e revoluções por minuto (rpm) do volante acoplado ao eixo do protótipo, o que permitiu estimar sua potência de saída e as condições operacionais, como a temperatura do gás nos espaços de compressão e expansão, etc. A comparação entre a simulação computacional e os resultados dos ensaios em bancada demonstrou a influência dos dados construtivos do protótipo (volumes, temperatura da fonte, etc.) sobre a potência de saída e o rendimento do protótipo e também o quão distante está o dispositivo construído do modelo ideal proposto por Schmidt. Os resultados obtidos pelos ensaios mostraram que o protótipo alcança velocidade de rotação de até 1.200 rpm a uma temperatura de 159 graus Celsius da fonte térmica externa ao motor, com potência de saída de 100 miliwatt. O protótipo resultante desta pesquisa, apesar de pequeno porte, permitiu a obtenção de informações importantes que podem abrir caminhos para a construção de motores Stirling de maiores dimensões e consequentemente com valores de potências de saída para utilização prática.