Browsing by Author "Rezaie, Behnaz"

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    Analysis of alternative energy options for buildings
    (2009-08-01) Rezaie, Behnaz; Esmailzadeh, Ebrahim; Dincer, Ibrahim
    The importance of utilizing different types of energy and their technical application is discussed. Awareness around the globe about the world energy crisis and its critical environmental condition has put more emphasis on the use of renewable energies in every corner of life. It is a well‐known fact that global warming, inefficient use of energy and greenhouse gases are damaging the environment, species and human life drastically. These issues will be discussed in recently conducted research. To address the crucial state of our environment, two simultaneous scenarios are considered. Initially, energy conservation and the switch to a low carbon/no carbon fuel are studied. As for energy conservation in buildings, smart methods in the use of energy in buildings are discussed. Based on different research reported, humans must change their attitude toward the use of resources, and in particular, be conscientious about energy consumption. Next, renewable energy promises a suitable alternative to energy needs in this century, and the best means to overcome the environmental issue and energy crisis is discussed. The practical methods of calculation for solar technology equipment, ground source heat pumps, and wind turbines are explained. In the application part of the study, four buildings are chosen as case studies; two of them from residential sectors, one is a commercial/institutional building, and the fourth is an industrial building. A ground source heat pump for heating and cooling, a solar water heater for heating space or hot water, and a photovoltaic panel for generating electricity are designed for the case studies. Even projects under hybrid systems combined from two technologies are designed. 36 different energy options are calculated for the four case studies. Results show that if a target is reducing CO2 emissions, what systems are the best. In contrast, when decision making is based on budget, what system is the first choice? Not only are technology, environmental protection and cost the main parameters for deciding on renewable technologies, but so are reliability, installation, maintenance and ease of use. Hence, renewable energy systems are categorized based on a broad vision.
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    Assessing district energy systems performance integrated with multiple thermal energy storages.
    (2013-08-01) Rezaie, Behnaz; Rosen, Marc A.
    The goal of this study is to examine various energy resources in district energy (DE) systems and then DE system performance development by means of multiple thermal energy storages (TES) application. This study sheds light on areas not yet investigated precisely in detail. Throughout the research, major components of the heat plant, energy suppliers of the DE systems, and TES characteristics are separately examined; integration of various configurations of the multiple TESs in the DE system is then analysed. In the first part of the study, various sources of energy are compared, in a consistent manner, financially and environmentally. The TES performance is then assessed from various aspects. Then, TES(s) and DE systems with several sources of energy are integrated, and are investigated as a heat process centre. The most efficient configurations of the multiple TESs integrated with the DE system are investigated. Some of the findings of this study are applied on an actual DE system. The outcomes of this study provide insight for researchers and engineers who work in this field, as well as policy makers and project managers who are decision-makers. The accomplishments of the study are original developments TESs and DE systems. As an original development the Enviro-Economic Function, to balance the economic and environmental aspects of energy resources technologies in DE systems, is developed; various configurations of multiple TESs, including series, parallel, and general grid, are developed. The developed related functions are discharge temperature and energy of the TES, and energy and exergy efficiencies of the TES. The TES charging and discharging behavior of TES instantaneously is also investigated to obtain the charging temperature, the maximum charging temperature, the charging energy flow, maximum heat flow capacity, the discharging temperature, the minimum charging temperature, the discharging energy flow, the maximum heat flow capacity, and performance cycle time functions of the TES. Expanding to analysis of one TES integrated with the DE system, characteristics of various configurations of TES integrated with DE systems are obtained as functions of known properties, energy and exergy balances of the DE system including the TES(s); and energy and exergy efficiencies of the DE system. iv The energy, exergy, economic, and CO2 emissions of various energy options for the DE system are investigated in a consistent manner. Different sources of energy considered include natural gas, solar energy, ground source heat pump (GSHP), and municipal solid waste. The economic and environmental aspects and prioritization, and the advantages of each technology are reported. A community-based DE system is considered as a case study. For the considered case study, various existing sizing methods are applied, and then compared. The energy sources are natural gas, solar thermal, geothermal, and solid waste. The technologies are sized for each energy option, then the CO2 emissions and economic characteristics of each technology are analysed. The parallel configuration of the TESs delivers more energy to the DE system compared with other configurations, when the stored energy is the same. With increasing the number of parallel TESs results in a higher energy supply to the DE system. The efficiency of the set of the TESs is also improved by increasing the number of parallel TESs. The tax policy, including the tax benefits and carbon tax, is a strong tool which will influence the overall cost of the energy supplier’s technology for the DE systems.The Enviro-Economic Function for the TESs is proposed and is integrated with the DE system, which suggests that the number of TESs required. The energy and exergy analyses are applied to the charging and discharging stages of an actual TES in the Friedrichshafen DE system. For the Friedrichshafen DE system, the performance is analysed based on energy and exergy analyses approach. Furthermore, by using the developed functions in the present study some modifications are suggested for the Friedrichshafen DE system for better performance.