Sharif Digital Repository

Despite the abundant renewable energy sources, the Iranian energy sector relies almost entirely on fossil fuel energy resources. Power sector is dominant source of CO2 emissions and responsible for about 35% of total CO2 emissions in the country. Additionally, long-term electricity demand of Iran is expected to grow quickly, which in turn requires extensive investment to meet the growing demand over the next decades. On the other hand, increasing domestic fossil fuel consumption had been a serious challenge due to high costs of oil and gas. Current study pays particular attention to the possible penetration rates of renewable electricity technologies and their implications for fossil fuel... 

Renewable energies as a solution for environmental issues have always been a key research area due to Demand Response Programs (DRPs). However, the intermittent nature of such energies may cause economic and technological challenges for Independent System Operators (ISOs) besides DRPs, since the acceptable effective solution may exceed the requirement of further investigations. Although, previous studies emphasized employing Demand Response and Renewable Energies in power systems, each problem was investigated independently, and there have been few studies which have investigated these problems simultaneously. In these recent studies, authors neither analyzed these problems simultaneously... 

Iran, as a developing country, will be confronted with a significant increase in electricity demand in future years. Being a petroleum producing country has resulted in extreme subsidies for energy production from fossilized resources such as oil and gas. This issue is one of the most important factors regarding underdevelopment of renewable energies in Iran. Expansive use of fossil resources in providing the necessary energy has resulted in Iran being among the 20 countries that have a share in the 75% spread of greenhouse gases. This issue has resulted in greater attention on behalf of the energy sectors policy makers regarding renewable energies, especially wind. Awareness regarding the... 

Tethered airborne wind energy systems are among emerging renewable energy technologies in recent years. These systems can harness greater power densities at higher altitudes with lower costs of installation and energy production in comparison with those from conventional ground-based energy harnessing technologies. A Buoyant Airborne Turbine (BAT) as a flying aerostat has a horizontal axis wind turbine within its shell and can elevate up to 600m. There are a number of pertinent parameters such as BAT configurations/component dimensions or its aerodynamic characteristics that impact the system total power performance. Identifying the optimum values of these parameters by conducting... 

Today, energy crises attracted many researchers’ attention to renewable energy technologies especially photovoltaic (PV) systems. The main challenge of PV systems is unpredictable nature of solar power generation. To overcome this challenge, a storage system is integrated which reduces demand reliance on electricity grid and uses excess energy that solar panels produce. As investment cost of the storage system is considerable, finding an optimal technology, size, and configuration are crucial. In this paper, the optimal battery system is excluded from existing PV plant installing in a commercial building located in Mashhad/Iran. Here, the sizing procedure is based on a financial evaluation... 

A deterministic energy supply model with bottom-up structure has limited capability in handling the uncertainties. To enhance the applicability of such a model in an uncertain environment two main issues have been investigated in the present paper. First, a binomial lattice is generated based on the stochastic nature of the source of uncertainty. Second, an energy system model (ESM) has been reformulated as a multistage stochastic problem. The result of the application of the modified energy model encompasses all uncertain outcomes together and enables optimal timing of capacity expansion. The performance of the model has been demonstrated with the help of a case study. The case study has... 

Increasing energy demands for pollution-free and renewable energy technologies have stimulated intense research on the development of inexpensive, highly efficient, and stable non-noble metal electrocatalysts for oxygen evolution reaction (OER). In this study, a superior OER performance was achieved using a tri-metallic (Zn, Co, Ni) high-performance electrocatalyst. We successfully fabricated a peony-flower-like hierarchical ZnCo2O4 through an additive-free hydrothermal reaction followed by heat treatment. Then NiCo-LDH (layered double hydroxides) nano-flakes was electrodeposited on the ZnCo2O4/GCE surface to prepare NiCo-LDH/ZnCo2O4/GCE which was used as electrode for OER. The structure and... 

Growing demands for clean and renewable energy technologies have sparked broad research on the development of highly efficient and stable non-noble metal electrocatalysts for oxygen evolution reaction (OER). In this regard, in the present work a three-dimensional Fe2TiO5/nitrogen-doped graphene (denoted as 3D FTO/NG) hybrid electrocatalyst was synthesized via a facile in-situ process using a hydrothermal method. Structural characterization of the prepared nanocomposite is performed by various techniques e.g. field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) analysis, Fourier transform infrared spectra (FT-IR), X-ray photoelectron spectroscopy spectra (XPS),...