Sharif Digital Repository

Due to the energy crisis in recent years, much of which is due to excessive energy consumption in the air conditioning of buildings, many studies have been conducted from the perspective of engineering sciences on the subject of insulation and optimization of buildings. This study aims to investigate the conditions of thermal comfort from the mental and psychological perspective of human beings, which is the basis of the individual's decision to accept thermal adaptation behavior in the standard temperature range. In this study, the thermal adaptation model was designed on the theory of programmed behavior, which can explain the adaptation of individuals to the comfort temperature region.... 

Today, financial exchanges have taken on a new form and cryptocurrencies were able to have a special place in these exchanges. Cryptocurrencies have attracted a lot of attention due to their decentralized nature. One of these cryptocurrencies is called Bitcoin and has the largest share of cryptocurrency exchanges. Due to the high volume of Bitcoin exchanges, a lot of energy is needed to supply this decentralized network to confirm transactions and extract it. In order for people in this industry to continue mining Bitcoin, they need to maintain their profitability. Therefore, choosing low consumption and profitable miners is one of the requirements of this industry. The aim of the thesis is... 

In the past due to the lack of mechanical systems for air conditioning in the interior spaces, the buildings were designed to be able to maximize the use of natural forces such as solar and wind power. Natural ventilation is an old method of using natural forces. For example, wind tower is one of the traditional elements for using natural ventilation in the warm seasons for benefiting from wind and sun energy. In our country, Iran, in cities like Yazd, which are located in a warm and dry climate, the use of wind towers is very common and our predecessors were pioneer in this field. With the passage of time and the development of mechanical air conditioning systems, the use of natural... 

Increase in electricity demands and expansion cost of the power system as well as raising more concerns on environmental issues have led to increasing attraction towards Distributed Generation (DG) application in power systems. DG is generally defined as small generation units, ranging from several KW to several MW, that are installed on the distribution network. In Iran, the energy generated by DG units is purchased by Tavanir or distribution companies through guaranteed fixed-price purchase contract. The contract price imposes substantial effects on the cost and benefit of DG owners as well as those of the distribution company (DisCo). A logical and fair pricing model can provide more... 

In this thesis, the problem of building energy prediction modeling is investigated using system identification method. Since system identification method has lower error and high accuracy than other methods of building energy prediction. This method was used to model the energy prediction of the building of the Faculty of Energy Engineering.In this method, the different thermal areas of the building are divided into two groups: central and surrounding areas for modeling purposes. The sunscreens are not used in the model but are added to other system inputs in the thermal areas around these two inlets.Given that it is difficult to obtain planning for the presence of persons and the use of... 

By increasing the penetration of distributed generation (DG) technologies such as photovoltaiec, μCHP etc, power generation system is moving from a centralized network to a distributed scheme with different generation units at lower level of voltage.This trend will provide the opportunity for cosumers to make decision when and which source of energy to use, due to the owner’s objectives. Here, to investigate these aspects, we use the energy hub framework, considering different energy carrier networks, DGs and storage devices. In this thesis, we model and simulate an energy system containing three interconnected energy hubs, which serve as interface between suppliers and consummers. In an... 

One of the issues that today is considered by planners and system operators in power systems, especially the Iranian power grid, is the high variation and the lack of uniformity of load curves in different hours of the day. This has led to the use of all installed capacity of the country's production only in peak hours, and in the low and intermediate times, a large amount of installed capacity is out of the circuit, which means Unused capital. This problem is more or less seen in world power networks with high load variation curves. Also, the production of renewable energies has always been fluctuating, and the production of power control to improve this fluctuation is very important. This... 

The rapid increasment of energy carriers and investment expenses in recent years, has increased the costs of energy demand and attracted those interested in consume reduction and efficiency using modern cutting-edge technologies. This research intends to design a general framework for optimization and energy and water demanding management studies in a sample region, regarding the new concept, energy hub.Thus as the first step, the existing industries and technologies with their thermal and electrical demands is considered as the first hub and wastewater treatment plant with its other equipments and thermal and electrical demands is considered as the second hub. The main issue in the modeling... 

The importance of optimizing the extraction process of available resources increases each day due to the increasing energy consumption and the lack of energy resources. Oil and gas are one of the most important sources of energy. Although existing oil and gas resources are thought to be sufficient to meet the growing energy demand for the next few decades, given the non-renewable nature of these resources and the growing demand for oil and gas, it will become much harder to meet the future energy demand. Many existing oil fields are now in the process of maturing, and the discovery of large new oil fields is rare. As a result, new technologies must be used in the future to meet this demand,... 

Mass production of Plug-in Hybrid Electric Vehicle (PHEV) and requests for long trip capability necessisated development of fast charging station that can charge PHEV in a feuling time of a conventional vehicle. Fast charging station design requires a systematic approach to consider various related issues.
The aim of this thesis is to design a fast charging station. First, the daly demand for PHEV charging is modeled considering number and type of PHEV as well as level and pattern of daily driving of PHEV. Uncertainty in daily driving and in PHEV state of charge in the start of charging are also considered in modeling charging demand. An approach, then, is proposed for optimal design of... 

The ever-growing demand for energy has raised concerns on sustainability of energy supplies and their environmental impact. Energy efficiency in buildings has gained special interest due to its energy consumption share in national scale. One of the most promising approaches for reducing building’s energy consumption is using an intelligent building management system (BMS). These systems have proved to reduce energy consumption while increasing comfort, and hence have gained global, and more recently national, recognition. This research has been devoted to the development of an intelligent building management system for the building of Sharif Energy Research Institute (SERI). The proposed... 

Advancements in smart grid technologies have made it possible for consumers to play an effective role in electricity markets. One of the prominent options for consumers is participating in Demand Response (DR) programs. DR offers incentives designed to induce lower electricity use at times of high market prices or when grid reliability is jeopardized. Large industrial consumers who are potentially capable of directly participating into the wholesale day-ahead electricity markets, can make financial benefits by choosing appropriate strategies to take part in hourly DR programs. As well as participating in DR programs which can be used to manage electricity costs, minimizing electricity... 

As a long-established approach, the electricity and natural gas networks have been operated and planned independently. Nevertheless, in recent years there has been a significant progress in energy conversion technologies in microgrids, thus making the electricity and gas networks more connected on the costumers’ side and also enabling users to utilize each of the carriers interchangeably. This increasing correlation between the two networks has led us to a new approach called co-planning of electricity and natural gas networks.This thesis aimed to take a closer look at this new approach and tried to study different aspects of it. Based on the concept of useful energy, a new approach has been... 

In conventional planning methods for an isolated microgrid, loads’s performance is taken into account in a constant power factor. Also, Motor loads dynamics which might results in absorbing a reactive power up to a few times more than the load’s capacity isn’t considered in this methods. Another important issue in the microgrid’s stability is the microgrid’s spinning reserve. Due to the isolated microgrid’s disconnectivity and not considering these problems in small isolated microgrids, the possibility of an instability event in microgrid’s performance would rise enourmously. In this thesis, an isolated microgrid’s planning has been carried out based on a solar resource while taking into... 

Occurrence of natural disasters such as flood, windstorms, tsunamis and earthquakes has caused striking effects on critical infrastructures like power systems in recent decades. There are some examples of high-impact low-possibility (HILP) events which causes catastrophic effects on power systems. Traditionally, planning and operational studies of power system have been run taking into account some reliability metrics. Although, the reliability indices can represent the ability of a system in confronting with possible failures of components, they are unable to efficiently consider the effects of severe events such as earthquake and other HILP events. Moreover, traditional power systems were... 

Considering the increasing importance of energy conservation in recent decades, different technologies regarding energy system have been developed to satisfy this goal. Building section is responsible for a big portion of final energy consumption and greenhouse gasses emission around the globe. Utilizing energy consumption reduction techniques in the building sector is among the foremost solutions to achieve the energy conservation potentials in this sector which would be followed by a decline in greenhouse emissions. Considering the contribution of heating and coling systems in a building’s energy use, optimizing these systems could have a huge effect on a building’s final energy... 

Gasoline is the major fuel used in transportation sector, even though it's environmental associated concerns and energy security problems receive, and continue to receive, much debate. On the other hand, growth in Iran's population and economy might cause an increase in the amount of cars in the market, consequently, in the transportation sector. The proposed phenomenon will bring a degree of rising in consumption of gasoline together with air pollution, especially in the big cities. Energy policy has acknowledged to be significant step in developing long-term plans across the globe. In this regard, developing policy-based methods and models are of a great importance toward forecasting the... 

In order to actualize the development of sustainable and smart cities, load disaggregation plays such an important role for energy consumption optimization, load response, and distributed energy production network optimization. Researchers have observed that non-intrusive load monitoring is a low-cost method because it doesn't require multiple sensors, but it has issues with algorithm complexity, algorithm variety, and algorithm accuracy dependence on factors like data collection frequency and the type of energy-consuming equipment. In this research, an effort has been made to evaluate how sensitive certain algorithms are to adjustments in the frequency of data collection and the duration of... 

Many of today’s energy infrastructures need to be restructured to accompany the changes in the needs of humankind. On the one hand, more human activitie’s dependency on different energy carriers, and on the other hand, reduction of fossil fuels as the main energy resources, have caused that policies in many countries to be faced with fundamental changes in the area of energy. Optimal use of different types of energy carriers as an integrated system, is one of the main strategies that have been proposed to enhance energy efficiency. Using the concept of energy hub as the main key of integrated energy systems, this project intends to design a general framework for optimization and management... 

Traditionally, different energy carriers are operated and planned independently. In recent years, with the growth of technology, communication has increased between different energy carrier-systems, in particular within electricity and natural gas networks. The attention to the links between various energy carriers has led to the formation of a new concept called the Energy Hub (EH). In this research, the problem of capacity development planning for gas power plant, CHP and boiler has been studied in a specified time horizon for several energy hubs, so as to meet the demand for electrical and thermal energy. It is worthy to note that the development of electricity and natural gas...