Sharif Digital Repository

Ever-increasing energy consumption and consequent extensive greenhouse gas (GHG) emissions have become two major global challenges for all human beings in the 21st century. If this trend of increasing energy consumption continues, our primary energy reserves willbe exhausted very soon.One solution is, shift of primary energy resources from fossil fuels to renewable energy could greatly reduce the current heavy dependence upon fossil fuels. Renewable energies have small share in the global energy market, therefore couldn't be a main method in the mid-term. Because of the low efficiency and consequent extensive GHG emissions of the conventional power generation that producing major amount of... 

Low effiencies of equipments and lack of forecasting heat integration in some oil regions are the reasons of primary energy losses in these regions. Also there have been difficulties in providing electric power demands in regions separate from the state electricity network which is a barrier in front of exploiting all the potentials of the region. This research introduces a model that can lead to selection of optimal configuration of equipments and units in order to establish a CCHP system that answers variable electric, heating and cooling demands ensuring a safe margin of power generation. The model simultaneously has the ability to select between existing and new installable equipments.... 

Nowadays, due to expansion of the cities, growth in population and developments in technology, energy demand has increased extremely. Therefore responding this increased demand is a great challenge in political and economical management of all countries. Thus in recent years, cogeneration has become so popular between experts in the energy field because of its great efficiency and performance. The goal of this research is to design a controller based on a model which can predict the behavior of the cogeneration system. This controler is called “Mode Based Predictive Controller”. It utilizes the system in such a manner which has the lowest operation costs. This goal is obtained via modeling... 

increasing energy demand and emission of environmental pollutant as a result of using fossil fuels and increase in waste generated due to human activities resulted in considering this source as a partial substitute for fossil resources in power application . Hence in this project biomass is considered as source of energy for heat and power application. Having low quality energy is the most important difficulty for application this resource as an energy carrier, so, gasification is applied to convert this source to gas with higher quality one. Produced gas in gasification enters to a micro turbine to meet thermal and electrical demand of the Sharif energy research institute. To investigate... 

According to the economic and environmental considerations, the use of distributed generation, both renewable and non-renewable type, in distribution networks is increasing. Their power generation is determined either by weather conditions or customers’ control due to their needs, therefore it is beyond the control of dispatcher.
In this thesis, two common technologies of distributed generations, including wind turbines and micro-CHPs, have been considered and the effects of their generations and penetrations on distribution network load and other network parameters have been evaluated.
Power generation of micro-CHP units and its side effects, is dependent on the customers’... 

In this project, a co-generation system with the operation capacity of less than 1000 kilowatts has been studied. The main purpose of this project is to help decision makers in order to choose proper combination of micro turbines and/or reciprocating engines, with certain rating capacity, as the prime movers of this co-generation system. Some factors that have been considered in the decision making process are prime mover operation in various ambient temperatures, various altitudes and part-load conditions and also operational restrictions such as power to heat ratio, maintenance cost ratio and prime movers plant factor and also economic characteristics such as investment and operating cost... 

In the present study by subject optimal structure design of a polygeneration process, has been trying to obtain an optimal structure of a simultaneous production of methanol and power with the approach of green design based on economic and environmental criteria, discussed and examined. In fact, a new approach to green design solution removes environmental pollutants, not just the final refinement rather tried from the beginning to the process, which is designed to produce less pollution. This period coincides took the idea that design engineers concluded that in order to achieve an optimum design, putting together the correct process equipment is effective as design of the individual... 

Nowadays, the reduction of crude oil quality and the growth of environmental restrictions are the main challenges in oil refineries worldwide. The high demand of lighter refinery products and the shrinking market of the heavy products, highlighted the role of heavy residues conversion technologies.Gasification technology consumes these heavy refinery residues and produces clean syngas. By this way and the integration of gasification with power generation cycles, more value added products such as electrical energy, steam and hydrogen can be provided. For this aim to be achieved, three different scenarios are developed and investigated in this project. The first scenario includes the... 

In recent years, providing sustainable water supplies in dry and low water areas in the south of country is one of the important problems in the country. In addition to advantages of using cogeneration systems (power plant and desalination unit), using hybrid technologies causes productivity and reduction in energy consumption and water supplies. The target of this thesis is studying different thermal coupling scenarios to find optimum and constraint design in specific conditions in terms of cost and production. So in this conceptual study, by using thermoflow software, the hybrid unit coupled with a back pressure and condensing combined cycle power plant was studied based on thermodynamic... 

The purpose of the current study is the thermodynamic, economic and environmental analysis of a cogeneration system capable of generating power, freshwater and/or air conditioning (AC) used in buildings. A photovoltaic-thermal system was used in conjunction with a concentrated reflector in order to generate power and heat. Photovoltaic cells and the cogeneration cycle turbine were tasked with generating electric power. In addition, a portion of the heat generated by the thermal collector was used to preheat the working fluid of the third-generation cogeneration cycle and another portion was used to produce freshwater. In order to provide the AC needed during summer, the cogeneration cycle... 

The present thesis aimed to study a novel heat pump integrated humidification-dehumidification (HDH-HP) desalination system. A theoretical outline was proposed for the first time to examine the design and off-design performance of HDH-HP cycles via the compressor characteristics method. In this regard, the variations in heat pump performance were modeled in different operating conditions for a fixed-size system. To fabricate a compact HDH-HP system, an evaporative condenser was designed and used instead of a separate humidifier, heater, and air/water-cooled condensers find in previous HDH-HP systems. Meanwhile, the air dehumidification process in this work directly occurred inside the heat... 

There is a growing potential for the use of micro-cogeneration systems in the residential sector because they have the ability to produce both useful thermal energy and electricity from a single source of fuel such as oil or natural gas. Benefits of cogeneration system will cover around 25% of internal electricity needs of ceramic, around 30 % saving in global fuel consumption, reduction of carbon dioxide. In tile factories, there is a system called a spray dryer. This system can use hot air to produce the soil needed to produce ceramic tiles. This hot air is supplied by a very large burner. In developed countries, instead of a burner, a gas turbine is used to produce hot air, with the...