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Design and Analysis of an Embedded Pipe Network in Asphalt Pavements to Reduce the Urban Heat Island EffectCarelli, Jonathan J. 03 May 2010 (has links)
Urban areas contain significant amounts of asphalt pavement. When exposed to the sun, asphalt pavement absorbs solar radiation and stores it as thermal energy raising its temperature. According to the urban heat island effect (UHIE), the pavement releases the thermal energy back to the surrounding air resulting in a rise in local air temperature. A pipe network containing a passing fluid installed in the pavement can reduce the UHIE. The fluid captures the thermal energy stored in the pavement, reducing air and pavement temperatures as well as providing heated water for other applications. The heat transfer/harvesting system can be optimized to produce the desired cooling of the pavements. This research addresses the economic feasibility of a pipe network by design as well as structural performance through computer modeling. To design the pipe network and predict its economic feasibility an Excel spreadsheet was programmed. It requires local air temperature data to determine the yearly temperature profile within the pavement and to calculate the amount of thermal energy that could be extracted. By varying design parameters such as fluid flow rate, it produces a matrix of payback periods. Structural conditions were considered for the installation of the proposed system. To simultaneously evaluate the thermal and structural performance of the pipe network installation, a finite element model was created using COMSOL Multiphysics©. A typical value of solar radiation and a standard truck tire wheel load were applied to the model to simulate the intended application of the pipe network. The result of this thesis is a method and a tool to design and analyze with respect to economic and structural performance a pipe network used to extract the thermal energy stored in asphalt pavements and reduce the UHIE.
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An Economic Analysis of Farm Flock Sheep Production in UtahBeck, Ken 01 May 1981 (has links)
The purpose of this study was to evaluate the economic aspects of farm flock sheep production in Utah. Using 1979 as a base year, costs and returns were calculated from data obtained from twenty- six Utah farms. Characteristics that typify the states· farm flock sheep production, at this writing, with regard to: 1) the farm flock producers and 2) the farm flock enterprise, were presented.
Various models were dev eloped and examined using Multiple Regression and Linear Programming analytical techniques. Multiple Regression was us ed to estimate the effects that different variables had on the profitability of the sheep enterprise. The most significant variables were found to be: 1) the number o f years each producer has been involved in sheep production and 2) number of years rams are retained for breeding purposes. Linear Programming was used to maximize the relative net returns between : 1 ) a traditional method of farm flock sheep production in Utah. 2) an accelerated production program where three lamb crops are produced in two years, and 3) an intensive program where two lamb crops are produced in one year. The accelerated lambing program producing three lamb crops in two years consistently demonstrated the highest relative net return. Recommendations of future related research were also included.
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An Economic Analysis of Selected Livestock Enterprises in Relation to the Available Feed Supplies, Utah, 1968Woolf, Ronald Jay 01 May 1970 (has links)
A study was made to determine the relative profitability and competitive position of cattle fattening, lamb fattening, and milk production in the state of Utah for 1968.
Production costs of cattle fattening ranged from $22.10 to $32 .28 per hundred pounds of gain . Net return amounted to $19.65 per head. Lamb fattening costs ranged from $24.25 to $29.76 per hundred pounds of gain . Net return from lamb feeding operations averaged $2.06 per head . Cost of producing milk amounted to $4.90 per hundredweight while net return amounted to $.61 per hundredweight.
Measure of profitability used 1n comparison included $100 worth of feed fed, return per hour of labor, and return per $100 invested in fixed assets .
Lamb fattening was the most profitable of the selected enterprises. Return per $100 worth of feed fed amounted to $35.46, $25.35, and $21.68 for lamb fattening, cattle fattening, and milk production respectively. Based on return per hour, lamb fattening , cattle fattening, and milk production contributed $10.08, $8.50, and $2.49 per hour respectively. Labor requirement was much higher for milk production than the other enterprises.
Return per $100 invested showed lambs again to be the most profitable showing a return of $79.54. Cattle fattening was second with a return of $69.73 while milk production with its high investment per cow showed only $24 .00 return per $100 invested in fixed assets.
All three selected enterprises could pay as high as $28.00 per ton for alfalfa and $2.60 per hundredweight for barley without causing a negative return.
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An integrated approach for techno-economic and environmental analysis of energy from biomass and fossil fuelsMohan, Tanya 25 April 2007 (has links)
Biomass conversion into forms of energy is receiving current attention because of environmental, energy and agricultural concerns. The purpose of this thesis is to analyze the environmental, energy, economic, and technological aspects of using a form of biomass, switchgrass (panicum virgatum), as a partial or complete replacement for coal in power generation and cogeneration systems. To examine the effects of such a substitution, an environmental biocomplexity approach is used, wherein the agricultural, technological, economic, and environmental factors are addressed. In particular, lifecycle analysis (LCA) and a three-dimensional integrated economic, energy and environmental analysis is employed. The effectiveness of alternate technologies for switchgrass preparation, harvest and use in terms of greenhouse gas impact, cost and environmental implications is examined. Also, different scenarios of cofiring and biomass preparation pathways are investigated. Optimization of the total biomass power generation cost with minimum greenhouse gas effect is undertaken using mathematical programming for various alternate competitive biomass processing pathways. As a byproduct of this work a generic tool to optimize the cost and greenhouse gas emissions for allocation of fuel sources to the power generating sinks is developed. Further, this work discusses the sensitivity of the findings to varied cofiring ratios, coal prices, hauling distances, per acre yields, etc. Besides electricity generation in power plants, another viable alternative for reducing greenhouse gases (GHGs) is the utilization of biomass in conjunction with combined heat and power (CHP) in the process industries. This work addresses the utilization of biowaste or biomass source in a processing facility for CHP. A systematic algebraic procedure for targeting cogeneration potential ahead of detailed power generation network design is presented. The approach presented here effectively utilizes the biomass and biowaste sources as external fuel, and matches it with the use and dispatch of fuel sources within the process, heating and non-heating steam demands, and power generation. The concept of extractable energy coupled with flow balance via cascade diagram has been used as a basis to construct this approach. The work also discusses important economic factors and environmental policies required for the cost-effective utilization of biomass for electricity generation and CHP.
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Economic Analysis of Alternative Irrigation Technologies: Texas Lower Rio Grande ValleyWilbourn, Brant 1987- 14 March 2013 (has links)
The focus of this study is the economic feasibility of drip irrigation adoption using capital budgeting and quadratic programming techniques. The capital budgeting techniques used in the study are net present value (NPV) and returns above specified costs (RASC). Modified crop enterprise budgets incorporating drip irrigation are developed based on data from Texas AgriLife Extension Service crop enterprise budgets and published literature focusing on costs and returns of drip irrigation. The quadratic programming technique considers risk and incorporates the modified crop enterprise budgets to estimate a cropping pattern that maximizes the net income above specified costs for the region.
The RASC per acre for drip-irrigated crops ranged from $56.34 to $1,909.03, while the RASC per acre for flood-irrigated crops ranged from $142.51 to $1,488.12. Flood-irrigated onions, cotton, and sugarcane had higher RASCs per acre, while the RASCs were greater for drip-irrigated grapefruit and oranges. Evaluating the NPV of the crops resulted in similar results; only grapefruit and oranges were economically-feasible drip-irrigated crops.
The baseline results identified levels of drip irrigation adoption ranging from 52,000 acres to 64,497 acres as levels of risk were varied. The level of water available at the reservoir suggested minimal impacts on the level of drip-irrigation adoption, but serious implications for the agriculture economy. Several sensitivity scenarios concentrated on the implications of yield response and water savings that result from the adoption of drip irrigation. The greatest amounts of drip-irrigated crops were present when the yield responses were 130% of the flood-irrigated crops with a 20% water savings. As the amount of water available was reduced, the amount of drip-irrigated crops ranged from 46,111 acres to 59,724 acres.
Drip irrigation appears to be an economically-viable alternative in the LRGV due to the presence of drip-irrigated crops in the entire myriad of scenarios investigated in this research. If producers are only concerned with the bottom line as provided by the RASC analysis and no other variables such as water availability, risk, and crop rotations affecting the decision making process, only drip-irrigated grapefruit and oranges are economically competitive with conventional irrigation systems.
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The Economic Analysis of Public Goods with NIMBYChen, Yen-Hua 09 May 2000 (has links)
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An integrated approach for techno-economic and environmental analysis of energy from biomass and fossil fuelsMohan, Tanya 25 April 2007 (has links)
Biomass conversion into forms of energy is receiving current attention because of environmental, energy and agricultural concerns. The purpose of this thesis is to analyze the environmental, energy, economic, and technological aspects of using a form of biomass, switchgrass (panicum virgatum), as a partial or complete replacement for coal in power generation and cogeneration systems. To examine the effects of such a substitution, an environmental biocomplexity approach is used, wherein the agricultural, technological, economic, and environmental factors are addressed. In particular, lifecycle analysis (LCA) and a three-dimensional integrated economic, energy and environmental analysis is employed. The effectiveness of alternate technologies for switchgrass preparation, harvest and use in terms of greenhouse gas impact, cost and environmental implications is examined. Also, different scenarios of cofiring and biomass preparation pathways are investigated. Optimization of the total biomass power generation cost with minimum greenhouse gas effect is undertaken using mathematical programming for various alternate competitive biomass processing pathways. As a byproduct of this work a generic tool to optimize the cost and greenhouse gas emissions for allocation of fuel sources to the power generating sinks is developed. Further, this work discusses the sensitivity of the findings to varied cofiring ratios, coal prices, hauling distances, per acre yields, etc. Besides electricity generation in power plants, another viable alternative for reducing greenhouse gases (GHGs) is the utilization of biomass in conjunction with combined heat and power (CHP) in the process industries. This work addresses the utilization of biowaste or biomass source in a processing facility for CHP. A systematic algebraic procedure for targeting cogeneration potential ahead of detailed power generation network design is presented. The approach presented here effectively utilizes the biomass and biowaste sources as external fuel, and matches it with the use and dispatch of fuel sources within the process, heating and non-heating steam demands, and power generation. The concept of extractable energy coupled with flow balance via cascade diagram has been used as a basis to construct this approach. The work also discusses important economic factors and environmental policies required for the cost-effective utilization of biomass for electricity generation and CHP.
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Dynamic Simulation and Economic Analysis of an Isolated Hybrid Wind Diesel SystemSelony, Wilson 24 June 2008 (has links)
An isolated hybrid system comprised of a dispatchable and a non-dispatchable power generation sources, is proposed to supply the load of a remote village in the west region of Haiti. The wind speed data and load data of this remote village are used to study the system. The non-dispatchable generation comes from a nature-dependent wind turbine, and the dispatchable one is a diesel generator. Using MATLAB/Simulink, dynamic simulations are performed to investigate the interaction between these two power sources for the load management, and the voltage and frequency behaviors during wind speed and load variations. Economic analyses of the
system are also conducted. The cost of energy (COE), energy payback time (PBT), internal rate of return (IRR) and avoided cost (AC) of CO2¬, NOx and PM (Particles Materials) of the hybrid system are computed, and results are compared with those of the baseline diesel only case. Simulation results show that the wind turbine and the diesel generator can be operated suitably in parallel, and the economic analyses show the positive benefits of wind generation in reducing COE and increasing the avoided
cost (AC) of emitted pollutions.
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Techno-economic assessment of solar technologies and integration strategies for the Canadian housing stockNikoofard, Sara 29 August 2012 (has links)
Energy security is probably one of the most challenging issues around the world. Therefore, the focus on methods of decreasing energy consumption and consequently its associated greenhouse gas (GHG) emissions is intensified by policy decision makers. Residential buildings are one of the potential sectors that can reduce its energy consumption in various ways, such as: improving thermal characteristics of the building, using more energy efficient appliances and using renewable energy resources. Among these methods, integration of solar technologies to buildings provides one of the substantial opportunities for reducing energy consumption and the associated GHG emissions in Canada’s residential sector. Therefore, this research work was conducted to assess the impact of solar technologies and solar technology integration strategies on the end-use energy consumption and the associated greenhouse gas (GHG) emissions in Canadian residential sector by using a new state-of-the-art end-use energy and GHG emissions model of the Canadian residential housing stock.
The new Canadian residential end-use energy and emissions model that is used in this project incorporates a 17,000 house database developed using the latest data available from the Energuide for Houses database, Statistics Canada housing surveys, and other available housing databases, and utilizes an advanced building energy simulation program as its simulation engine. A new neural network methodology is incorporated into the model to estimate the socio-economic and demographic dependencies of the energy consumption of discretionary end-uses such as appliances, lighting and domestic hot water, while a new approach is used to incorporate occupancy, appliance, lighting and domestic hot water load profiles into the model. A new method is used to calculate the GHG emissions from electricity consumption used in the residential sector based on the actual electrical generation fuel mix and the marginal fuel used in each province as a function of time of the year.
Each solar technology is added to the eligible houses to examine the interrelated effects of integrated solar technologies and practices on the housing stock. The objective is to conduct realistic assessments of the cost effectiveness, energy savings and GHG emission reduction benefits of integrated solar technologies for the entire Canadian housing stock (CHS) as well as for different regions, house type, and fuel types. The integrated solar technologies and practices that are assessed include passive solar with added thermal storage and motorized blinds, solar DHW system, and photovoltaic electricity and heat generation systems.
This project provides a comprehensive techno-economic and emissions assessment of integrated solar technologies and practices, and will be useful for developing national and regional policies and strategies related with integrating solar energy into the residential sector.
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Thermo-economic Analysis of Retrofitting an Existing Coal-Fired Power Plant with Solar HeatShimeles, Surafel January 2014 (has links)
At a time when global environmental change is posing a growing challenge to the world’s economy and creating uncertainties to livelihood of its inhabitants, Coal thermal power plants are under pressure to meet stringent environmental regulations into achieving worldwide set millennial goals for mitigating the effect of emission gases on the atmosphere. Owing to its abundance, it is unlikely to see the use of coal completely missing from the global energy mix within the next hundred years to come. While innovative emission reduction technologies are evolving for the better, trendy technological solutions which require reintegration of these coal plants with alternative greener fuels are growing at the moment. Among these solutions, the following paper investigates possible means for repowering a coal steam power plant with indirect solar heating solutions to boost its annual outputs. Two widely deployable solar thermal technologies, parabolic trough and Central tower receiver systems, are introduced at different locations in the steam plant to heat working fluid thereby enhancing the thermodynamic quality of steam being generated. Potential annual energy output was estimated using commercially available TRNSYS software upon mass and heat balance to every component of solar and steam plant. The annual energy outputs are weighed against their plant erecting and running costs to evaluate the economic vitality of the proposed repowering options. The results show that parabolic trough heating method could serve as the most cost effective method generating electricity at competitive prices than solar only powered SEGS plants. While cost may be acceptable in the unit of energy sense, the scale of implementation has been proven to be technically limited. / Kriel Power Plant
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