Sharif Digital Repository

Limited fossil energy resources and problems with greenhouse gas emissions, has increasingly focused attentions on renewable energy as a solution to this issue. Marine energy due to the the vast amount of wind, current and wave available resources, can play a major role in providing renewable energy and reducing CO2 emissions. However, using one renewable energy, in some cases due to its high volatility and high costs is impractical. Combining different marine renewable energies, can be mentioned as a solution to increase competitiveness with fossil fuels. The aim of the current research, is to introduce a method to select the best location in terms of renewable energy farms wind, current... 

Renewable energy deployment through distributed energy resources is among the central goals of future power systems. Microgrids have proven to be an economically viable soloution for distributed energy resources integration into power system and benefit the customers with uninterrupted power supply. In this context provisional microgrids have been introduced with the main goal of rapid renewable energy sources deployment. Since a considerable portion of renewable enegy resources as well as residential loads are DC and this portion is expected to grow even further, hybrid AC/DC design of provisional microgrids can improve both efficiency and economic benefit by optimal arrangement of AC/DC... 

One of the challenges which increasing penetration of renewable energy sources with variable generation brings is the need for more flexibility in the power system. A promising way to overcome the challenge is to have local sources of the flexibility in distribution level. To this end, we present a new model for multi-stage distribution system expansion planning which jointly considers expanding the network assets and increasing the flexibility at local level by installing conventional dispatchable distributed generator units and energy storage systems. Demand response is also considered as another source of the flexibility which can be utilized by the system operator. Since deviating from... 

Increasingenergy requirements, limitedfossil resources, environmental pollutioncaused byfossilfuels, global warmingand other factorshaveled tothe approach ofscience and technologyfor renewable energies. One of the renewable energies is the energy relevant to ocean currents that is mainlydue to theinteractionbetween thetidalattraction ofthe moon,sun andearth. In our country,due tothehigh tideon the southern coast, there isgood potentialto use thistype of energy. One of themost favorableareasformarinecurrentpower plantslocated inthe northern part ofthe islandof Qeshmchannel.In this thesis,to exploitthis potential, the newidea ofHunter tidalturbine was investigated,because... 

In this project, a comprehensive methodology is developed to present the lifetime management and optimization framework for hybrid renewable energy systems. The main purpose of this work is to minimize the lifetime cost and improve the system reliability based on the interaction between different optimization levels related to different steps in the system lifetime. The proposed methodology is generally presented by providing a connection between the three specified optimization levels: 1) Planning: including design and long-term optimization models which is performed before system operation, 2) Real-time operation: By employing the receding horizon optimization which is applied from the... 

Wind energy, as a type of renewable energy resource, is clean and is rapidly growing globally. The intermittency in the production of wind energy is the most major obstacle for these producers in a competitive electricity market, to compete with thermal units. Most existing models in the literature mitigate the risk of wind power, by coordinating them with energy storages such as pumped storages power plant. Here, in this thesis, another risk mitigation approach is introduced which combines wind energy and natural gas power plant in an electricity market. In addition, as the penetration level of wind power grows, the wind power producers must be considered as a price-maker player which their... 

Nowadays, modern life needs energy resources. In the last few centuries, countries have focused on the use of fossil fuels. However, excessive use of fossil fuels, such as oil and coal, has resulted in enormous environmental hazards. Global warming and air pollution are the most visible manifestations of these hazards. In recent years, energy researchers have been looking for alternative sources. The result of this approach is to pay attention to clean and renewable resources such as wind energy.Wind turbines are used to generate electrical energy out of wind. Among the different types, floating offshore wind turbines have been mostly considered because of various benefits. However, they... 

The Cu2ZnSnS(e)4 (CZTS(e)) quaternary and Cu2SnS3 (CTS) ternary componds with suitable optical and electrical properties have been considered as an emerging semiconductors for fabrication of thin-fim solar cells. So far, two technologies based on CdTe and CuInGaS(e)2 absorbers have achived efficiencies above 20%. However, these compounds contain toxic element Cd and rare elements such as In and Ga which, limited the development of these solar cells.In this research a 3-stage method was used for fabrication of CZTS(e) thin Films. In the first stage, CTS layers were deposited by spray pyrolysis method, in the second one, ZnS layers were also deposited on CTS layers by spray pyrolysis method... 

In recent years, energy storage systems have received widespread attention from researchers to increase the reliability of the power grid. These systems have different types that compressed air system is of special importance due to its high stored energy and long life. In this system, the surplus of electricity generated from renewable energy sources or grid electricity at low power consumption is compressed and stored in a tank. When there is a need for power consumption or peak power consumption, compressed air will generate electricity by passing through the turbine and will help the network. Large-scale type of the system requires special geographical location for air storage; for this... 

Vertical ground-coupled heat pumps due to using a renewable energy stored in the ground and being away from ambient temperature fluctuations have a good coefficient of performance and very low pollution. Despite these advantages, these systems have not gained a pervasive position in the field of heating/cooling systems due to their high initial cost. Despite these advantages, these systems have not gained a pervasive position among communities due to their high initial cost. In the present project, a comprehensive study has been conducted to investigate the effect of using zeotropic refrigerant mixtures on the performance of vertical ground-coupled heat pumps and reducing its initial costs.... 

In recent years, and with the development of information technology in various aspects of life, the growth of energy consumption in this sector has accelerated. With the advent of cloud computing and the development of its users, data centers have become one of the largest consumers of energy in the world. Adverse effects of fossil fuel consumption on the one hand and the global energy crisis as a limiting factor for development, on the other hand, have doubled the importance of managing the issue and reducing energy consumption in this sector. The two main energy-related concerns in data center construction are clean energy and energy management. The use of new energy and natural facilities... 

Today, to reduce the effects of greenhouse gases on the earth, as well as reduce dependence on fossil fuels and other non-renewable sources, the international community is moving towards greater use of renewable energy. The oscillating water column device as a wave energy converter system has the ability to use and absorb energy within the waves through a chamber consisting an air and a water column. This system has the ability to move the turbine installed on the valve by expanding and compressing the air passing through the valve. Oscillating water column systems have different categories, and this high diversity makes the choice of this wave energy converter closely related to the... 

The present study aims to reduce the carbon footprint of greenhouse products to provide a decision tool for sustainable development of greenhouses. In order to provide this decision tool, the impact of four scenarios or energy-efficient technology for greenhouse heating, including: combine heat and power system(CHP), new greenhouse covering material, industrial symbiosis, and solar collector on the carbon footprint of greenhouse products has been studied because one of the main factors in the release of carbon footprints of greenhouse products is the use of fossil fuels for greenhouse heating. Energy modeling has been used to estimate the amount of heating, cooling, and artificial lighting... 

Energy production from fossil fuels such as oil and gas is one of the non-renewable energies, which causes many environmental problems such as global warming and environmental pollution. The existence of these problems has led to agreements such as the Glasgow Environmental Agreement, which obligates governments to apply methods to reduce the production of greenhouse gases, which include reducing the consumption of fossil fuels and increasing the use of renewable energy. Sea wave energy is one of the renewable energies that can be used to generate electricity. In the seas of Iran, including the Caspian Sea, Persian Gulf and Oman, there are sources of wave energy that can be used and are...