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OPERATION AND PLANNING OF COORDINATED NATURAL GAS AND ELECTRICITY INFRASTRUCTURES
Title
OPERATION AND PLANNING OF COORDINATED NATURAL GAS AND ELECTRICITY INFRASTRUCTURES
Creator
Zhang, Xiaping
Date
2015, 2015-07
Description
Natural gas is becoming rapidly the optimal choice for fueling new generating units in electric power system driven by abundant natural gas...
Show moreNatural gas is becoming rapidly the optimal choice for fueling new generating units in electric power system driven by abundant natural gas supplies and environmental regulations that are expected to cause coal-fired generation retirements. The growing reliance on natural gas as a dominant fuel for electricity generation throughout North America has brought the interaction between the natural gas and power grids into sharp focus. The primary concern and motivation of this research is to address the emerging interdependency issues faced by the electric power and natural gas industry. This thesis provides a comprehensive analysis of the interactions between the two systems regarding the short-term operation and long-term infrastructure planning. Natural gas and renewable energy appear complementary in many respects regarding fuel price and availability, environmental impact, resource distribution and dispatchability. In addition, demand response has also held the promise of making a significant contribution to enhance system operations by providing incentives to customers for a more flat load profile. We investigated the coordination between natural gas-fired generation and prevailing nontraditional resources including renewable energy, demand response so as to provide economical options for optimizing the short-term scheduling with the intense natural gas delivery constraints. As the amount and dispatch of gas-fired generation increases, the long-term interdependency issue is whether there is adequate pipeline capacity to provide sufficient gas to natural gas-fired generation during the entire planning horizon while it is widely used outside the power sector. This thesis developed a co-optimization planning model by incorporating the natural gas transportation system into the multi-year resource and transmission system planning problem.This consideration would provide a more comprehensive decision for the investment and accurate assessment for system adequacy and reliability. With the growing reliance on natural gas and widespread utilization of highly efficient combined heat and power (CHP), it is also questionable that whether the independent design of infrastructures can meet potential challenges of future energy supply. To address this issue, this thesis proposed an optimization framework for a sustainable multiple energy system expansion planning based on an energy hub model while considering the energy efficiency, emission and reliability performance. In addition, we introduced the probabilistic reliability evaluation and flow network analysis into the multiple energy system design in order to obtain an optimal and reliable network topology.
Ph.D. in Electrical and Computer Engineering, July 2015
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MODELING THE IMPACT OF NATURAL GAS VARIATION ON COMBUSTION IN A DUAL FUEL ENGINE
Title
MODELING THE IMPACT OF NATURAL GAS VARIATION ON COMBUSTION IN A DUAL FUEL ENGINE
Creator
Hulbert, Matthew Calvin
Date
2017, 2017-07
Description
The desire to meet rising energy demands while simultaneously adhering to stringent climate policies have propelled several advanced...
Show moreThe desire to meet rising energy demands while simultaneously adhering to stringent climate policies have propelled several advanced combustion technologies. The utilization of alternative fuels in internal combustion engines is a relevant solution to the immediate problems facing the transportation sector. Natural gas (NG) is an attractive alternative as it is economically and environmentally versatile, geographically diverse, and has clean-burning qualities which when coupled with dual fuel technologies has shown significant positive impacts on combustion characteristics. The present work describes the setup of an experimental test cell that contains a modern 2.0-liter 4-cylinder turbocharged direct-injected diesel engine that will be modified for dual fuel capability. The initial stages of a computationally efficient simulation model that represents the experimental engine are also presented and a discussion on the model’s development ensues. A dual fuel simulation model was created and calibrated against experimental data obtained from a heavy-duty 6-cylinder duel fuel engine. The objective of this work is to assess the affects different NG compositions have on the combustion process. Natural gas has shown to vary significantly, depending on where the fuel is acquired. The results show that methane content plays a significant role on combustion. As methane content increases, start of combustion (SOC) shifts and peak cylinder pressure decreases. The premixed combustion phase is shown to increase with decreasing methane content, while the mixing-controlled combustion phase decreases. Nitrogen oxides (NOx), carbon monoxide (CO), and carbon dioxide (CO2) emissions have demonstrated to be dependent on methane content. NG compositions with low methane content show increased amounts of CO2 emissions while high methane content shows a decrease in nitric oxide (NO) emissions.
M.S. in Mechanical and Aerospace Engineering, July 2017
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