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The growing interest in e-mobility and the increasing installation of renewable energy-based systems are leading to rapid improvements in lithium-ion batteries. In this context, battery manufacturers and engineers require advanced models in order to study battery performance accurately. A number of Li-ion battery models are based on the representation of physical phenomena by electrochemical equations...
We study the difference between urban and rural elasticities for electricity residential consumption in Portugal. Our sample covers the period from 1989 to 2010 and consists of five independent surveys. We adopt the pseudo-panel methodology creating 350 cohorts based on the size of the household, the type of location (rural or urban), the region, and the income quintile. Our results indicate that...
This paper aims to solve wind energy integrated electric power dispatch (EPD) problem from the perspectives of stochastic modelling and multiobjective optimization. At first, the competing objectives in modern electric power and energy system is analyzed and a new interval optimization model for each objective is proposed based on the uncertainties with respect to wind power. Then, a novel strength...
When photovoltaic (PV) array is operated under partially shaded condition (PSC), power-voltage curve will show multiply peaks. This causes the inability of conventional maximum power point tracking (MPPT) methods such as hill climbing (HC). To deal with this problem, this paper proposes a new MPPT method based on a modified cat swarm optimization (MCSO) to achieve global maximum power point (GMPP)...
Concentrated photovoltaic (CPV) technology as a typical PV application is becoming popular due to its advantages of high conversion efficiency and low cost etc. However an important issue for CPV technology is the non-uniformity on the illumination and the temperature which can finally influence the overall electrical efficiency of solar cells. This study presents the feature of the non-uniform illumination...
The paper describes the impact of different measures to improve the thermal performance of a solar heating plant for district heating applications. The impact of the different measures was evaluated through a validated TRNSYS-Matlab model. The model included details such as effect of the flow regime in the absorber pipes on the collector efficiency, flow distribution in the collector field, thermal...
Salt-gradient solar ponds are energy collectors and storage systems that provide continuous heat supply. Although many studies have investigated the thermal behavior of solar ponds, few researches have investigated how heat lost to the ground beneath a pond can be recovered. Here, a one-dimensional transient model is used to study the thermal interaction between a solar pond with constant heat demand...
Electricity demands are steadily increasing every year because of continued improvements to the quality of life and extreme hot and cold weather conditions. Therefore, the electric demand response management (DRM) system was introduced to prevent unstable electricity supply both domestically and globally. Unlike power generation in power plants, DRM regulates the demand and supply by reducing building...
In the present study, 14 existing temperature–based empirical models for daily horizontal global solar radiation estimation were comprehensively reviewed, and six new temperature–based models (P1P6) were developed for solar radiation estimation in humid regions. The accuracy and suitability of these models were further evaluated for the humid subtropical and tropical regions of China as a case study...
A combined cooling, heating, and power system based on biomass gasification is modeled via experiment and its performance is evaluated. The system operation is simulated using load data of small offices located in different climate zones in the U.S. The operation strategy comprises following the electric load (FEL) and following the thermal load (FTL). Based on the operation data, energetic, economic,...
The high variability of solar and wind energy sources makes their integration into power systems complicated and in some cases unnecessarily delays their transition from centralised to dispersed energy sources. In this paper, a mixed-integer non-linear mathematical model has been developed for simulating the integrated operation of a novel hybrid involving wind- and solar power and a hydroelectric...
This research presents the modelling and simulation of an innovative small-scale power system composed of a downdraft gasifier, an externally fired gas turbine (EFGT) and an Organic Rankine Cycle (ORC) as a bottoming unit for increasing the electrical energy generation. Olive tree pruning (217 kg/h) was the biomass used, producing more than 200 kWe and an electrical efficiency of 20.7%. The producer...
Different from gases separation technology using membranes and solvent, solvent-free gas separation technology is more economically and energy efficient. Due to its inherent low permeance of the membrane, the means using sweeping or vacuum are two main options to increase the mass flow rate of the fast gas (with higher selectivity) on the permeate side. This study models a typical membrane for CO2...
When planning a neighborhood-scale distributed energy system (NDES), enough attention should be paid to the urban spatial structure, which may affect not only the system configuration on the supply side but also the load profiles on the demand side as well as their interactions. In this study, a novel nonlinear optimization model is developed for the determination of neighborhood design and NDES arrangement...
This article presented a simplified method for quick estimating exergy destruction and irreversibility distribution ratio (φ) in a complex Heat Exchanger Network (HEN) of a large natural gas refinery in South Pars Gas Field located in the Persian Gulf. By the presented method, the designing of the HEN isn't required and the only necessary data are the temperatures and thermo-physical properties of...
Objective of this study is to elucidate relationship with aerodynamic properties and vortex shedding from suction surface and wake of wind turbine blade at low Reynolds numbers. Force measurement of NACA 4412 airfoil was conducted at various angles of attack and Reynolds numbers. Furthermore, smoke-wire experiment was performed to clearly visualize flow patterns such as flow separation or laminar...
Since the invention of the pulse tube refrigerator, improvements have mainly focused on developing new phase shifters, while the basic structure of the cold head is not changed much. With the combining of step piston pulse tube refrigerator with thermoacoustic refrigerator, a new concept called resonator pulse tube machine is proposed. It is investigated by a numerical simulation, which shows that...
Power output limitation is one of the main challenges that needs to be addressed for full-scale applications of the Microbial Fuel Cell (MFC) technology. Previous studies have examined electrochemical performance of different cathode electrodes including the development of novel iron based electrocatalysts, however the long-term investigation into continuously operating systems is rare. This work...
This paper focuses on realistically predicting the power outputs of wave energy converters operating in shallow water nonlinear waves. An oscillating surge wave energy converter (OSWEC) is utilized as a specific calculation example, and the generated power of the OSWEC has been predicted by using a new method (a nonlinear simulation method) that incorporates a second order random wave model into a...
This paper presents a rigorous investigation for efficiency, thrust, and fuel consumption optimization of a subsonic/sonic turbojet engine. A thermal model of the turbojet engine is developed for optimization investigation. A many-objective optimization problem is formed by considering maximization of thermal efficiency, propulsive efficiency, specific thrust and minimization of thrust-specific fuel...
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