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... With the different kinds of fuel now available, modern spark ignition engines have to be adapted, owing not only to the difference between the characteristic heat of combustion of the different fuels, but also to the response of the flame to stretch. As the burning rate is a function of the laminar burning speed which is a function of the flame stretch, this parameter has to be taken into account ...
catalysts; diffusivity; electrochemistry; electrodes; energy conversion; equations; fuel cells; mass transfer; metals; model validation; models; oxygen
Abstract:
... A 3D multi-physics, multi-component and not isothermal model is developed to analyze the effects of catalyst structures on the performance of a gas diffusion electrode (GDE) cell toward the oxygen reduction reaction using dry oxygen as a reactant. The model includes Stokes–Brinkman, Maxwell–Stefan, and modified Butler–Volmer equations for simulating the performance of the GDE cell, solved by Comso ...
... Thermal energy storage (TES) systems allow concentrated solar power (CSP) producers to participate in a day-ahead market. Therefore, the optimal power scheduling problem can be posed, whose objective is the maximization of profits derived from electricity sales. The daily generation schedule has to be offered in advance, usually the previous day before a certain time, thus an electricity price and ...
algorithms; climate; energy efficiency; lighting; shade; solar radiation
Abstract:
... In this paper we address the problem of designing new energy-efficient static daylight devices that will surround the external windows of a residential building in Madrid. Shading devices can in fact largely influence solar gains in a building and improve thermal and lighting comforts by selectively intercepting the solar radiation and by reducing the undesirable glare. A proper shading device can ...
boiling; carbon dioxide; control methods; cooling systems; energy use and consumption; greenhouse gas emissions; model uncertainty; models; spark ignition engines
Abstract:
... Optimal thermal management of modern internal combustion engines (ICE) is one of the key factors for reducing fuel consumption and CO2 emissions. These are measured by using standardized driving cycles, like the New European Driving Cycle (NEDC), during which the engine does not reach thermal steady state; engine efficiency and emissions are therefore penalized. Several techniques for improving IC ...
buildings; carbon; case studies; emissions; energy; energy costs; heat; mathematical models; stakeholders
Abstract:
... This paper presents a model which simultaneously optimises the selection and operation of technologies for distributed energy systems in buildings. The Technology Selection and Operation (TSO) model enables a new approach for the optimal selection and operation of energy system technologies that encompasses whole life costing, carbon emissions as well as real-time energy prices and demands; thus, ...
electric vehicles; electricity costs; fossil fuels; planning; wind power
Abstract:
... Electric vehicle (EV) is a promising, environmental friendly technique for its potential to reduce the using of fossil fuels. Massive EVs pose both opportunities and challenges for power systems, especially with the growing amount of wind-power integration. This paper investigates the problem of collaborative optimization scheduling of generators, EVs and wind power. A novel bi-layer optimization ...
... The paper proposes a bi-level optimisation framework for Electric Vehicle (EV) fleet charging based on a realistic EV fleet model including a transport demand sub-model. The EV fleet is described by an aggregate battery model, which is parameterised by using recorded driving cycle data of a delivery vehicle fleet. The EV fleet model is used within the inner level of the bi-level optimisation frame ...
energy; income; models; power plants; prediction; uncertainty; wind power; China
Abstract:
... To reduce the uncertain influence of wind power and solar photovoltaic power on virtual power plant (VPP) operation, robust optimization theory (ROT) is introduced to build a stochastic scheduling model for VPP considering the uncertainty, price-based demand response (PBDR) and incentive-based demand response (IBDR). First, the VPP components are described including the wind power plant (WPP), pho ...
bibliometric analysis; energy; fossil fuels; fuel combustion; prices; researchers; wind power; Europe; United States
Abstract:
... With the increasing negative effects of fossil fuel combustion, many countries have paid more attention on supporting environmentally friendly energy generation, particularly renewable and sustainable energy sources (RES). However, renewables still cannot economically compete with fossil-fuels and are facing new challenges. Appropriate electricity pricing mechanism plays a vital role on mitigating ...
carbon dioxide; climate; energy; energy policy; global warming; greenhouse gas emissions; lignite; prediction; rain; solar collectors; system optimization; temperature; time series analysis; wind turbines; Greece
Abstract:
... An approach for a plan to meet the energy needs of the state of Greece in conjunction with assumed responsibilities to confront global warming is presented. Time series of climate indicators like average temperature and rain precipitation together with energy consumption and CO2 emissions are examined for stationarity and causality. Predictions of energy needs for the next 25years and CO2 emission ...
carbon dioxide; fuels; convection; mass transfer; prediction
Abstract:
... This study presents a state-of-the-art overview on heat transfer characteristics of fluids (mainly water, carbon dioxide and hydrocarbon fuels) flowing in smooth tubes and enhanced tubes at supercritical pressures and tries to obtain a fundamental understanding of the unique characteristics. Heat transfer in enhanced tubes is much better than that in smooth tubes with a larger pressure drop penalt ...
batteries; lithium; longevity; model validation; models
Abstract:
... The incremental capacity (IC) analysis method is widely used to analyze the aging origins and state of health (SOH) of lithium ion batteries. This paper analyzes the technical difficulties during the application of the IC analysis method at first. A universal capacity model based on charging curve is then proposed, which not only inherits the advantages of IC analysis method but also avoids the te ...
carbon; carbon dioxide; global warming; greenhouse gas emissions; pressure; China
Abstract:
... Given the acceleration of global warming and rising greenhouse gas emissions, all countries are facing the harsh reality of the need to reduce carbon emissions. In this study, we propose an index to quantify the pressure faced by policymakers to reduce such emissions, termed the carbon emissions reduction index. This index allows us to observe the effect of carbon emissions volume on the pressure ...
... A pulse tube cryocooler (PTC) cannot work with Carnot efficiency due basically to the expansion work that has to be dissipated thermally at the warm end of the pulse tube, this dissipation is especially phenomenal with high cooling capacity or at high temperatures which reduces the COP and limits the application of PTC above 120K. Therefore, how to recover this amount of dissipated work becomes a ...
... Microfluidic fuel cell (MFC) stacking is a prerequisite to improve its power output for practical applications. Unlike the stacking of membrane-based fuel cells, MFC stacking generally involves complex fluidic management, such as anolyte and catholyte distribution, and spent electrolyte collection, which greatly increases the system’s complexity. In addition, the operational robustness of MFC stac ...
air temperature; buildings; energy; heat; heat island; heat sums; insulating materials; methodology; models; France
Abstract:
... Efficient strategies are required to reduce space heating energy demands in buildings at city scale. Models taking into account the dynamic of the Urban Heat Island (UHI) phenomenon may be useful tools to help urban planners in this task. In this paper, we propose a new methodology to assess the energy demands for space heating in buildings at city scale: a degree-day method is applied, coupled wi ...
air; entropy; friction; heat exchangers; heat transfer; models; temperature
Abstract:
... In the design of multistream plate-fin heat exchangers (MPFHEs), surface selection and layer pattern optimization have been investigated as two independent problems and still remain at the empirical stage, which becomes an obstacle for optimizing the performance of MPFHEs. A combined method of the equipartition of entropy production and the balance of local heat load is proposed in the present res ...
algorithms; case studies; electricity; industry; markets; models; seasonal variation; New South Wales; Queensland
Abstract:
... Short-term load forecasting (STLF) plays an irreplaceable role in the efficient management of electric systems. Particularly in the electricity market and industry, accurate forecasting could provide effective future plans and economic operations for operators of utilities and power systems. Hence, a more precise and stable load-forecasting model is essentially needed in the field of electricity l ...
air; air flow; combustion; energy conversion; fuels; heat recovery; internal combustion engines; methodology; models; wastes
Abstract:
... A novel intra-cycle waste heat recovery (ICWHR) methodology, applied to an internal combustion engine is presented in this study. Through a split type thermodynamic cycle design, quasi-isothermal compression of the charge air and isobaric combustion of the air/fuel mixture can be performed separately in two chambers. Within such a design, the exhaust heat can be recovered to the intake air flow be ...
... Despite the long-term benefit of battery electric vehicles (BEVs) to customers and environment, the initial cost and limited driving range present significant barriers for wide spread commercialization. The integration of multi-speed transmissions to BEVs’ powertrain systems in place of fixed ratio reduction transmissions is considered as a feasible method to improve powertrain efficiency and exte ...
... Efficient optimization algorithms are critical to the development of new engine technology. In this study, experimental investigations were carried out on optimizing the performance of a four-cylinder, turbocharged, direct-injection diesel engine running with soy biodiesel. An effective hybrid particle swarm optimization (PSO) and genetic algorithm (GA) method using a small population was develope ...
... Accurate state-of-charge (SOC) estimation is critical for the safety and reliability of battery management systems in electric vehicles. Because SOC cannot be directly measured and SOC estimation is affected by many factors, such as ambient temperature, battery aging, and current rate, a robust SOC estimation approach is necessary to be developed so as to deal with time-varying and nonlinear batte ...
lithium batteries; Monte Carlo method; experimental design; dielectric spectroscopy; temperature
Abstract:
... In order to guarantee safe and proper use of Lithium-ion batteries during operation, an accurate estimate of the battery temperature is of paramount importance. Electrochemical Impedance Spectroscopy (EIS) can be used to estimate the battery temperature and several EIS-based temperature estimation methods have been proposed in the literature. In this paper, we argue that all existing EIS-based met ...
data analysis; renewable energy sources; uncertainty analysis
Abstract:
... With increasing levels of integration of intermittent renewable energy in the power grid, it has become essential for power system planners to quantify future requirements of power systems in terms of flexibility. It is also equally important to evaluate whether the flexibility available in a given power system is adequate to meet more frequent and larger variations in the net load. In this paper, ...
energy; specific energy; models; vehicles (equipment); batteries; temperature; cold; recycling
Abstract:
... Because of their numerous advantages, lithium-ion (Li-ion) batteries have recently become a focus of research interest for vehicle applications. Li-ion batteries are suitable for electric vehicles (EVs) and hybrid electric vehicles (HEVs) because of advantages such as their high specific energy, high energy density, and low self-discharge rate in comparison with other secondary batteries. Neverthe ...
absorption; drying; energy; energy recovery; engineering; heat; heat pumps; industry; oil fields; petroleum; sludge; temperature; wastewater; China
Abstract:
... An industrial heat pump can upgrade heat from a low temperature level to a high temperature level with the aid of an external energy source. It has received considerable attention as an efficient means of waste energy recovery in the recent years in China. This paper summarizes the research work done and advances in the application of industrial heat pump systems in China, including advances in re ...
centrifugal pumps; energy conservation; energy efficiency; energy policy; environmental impact; global warming; ozonosphere
Abstract:
... The energy consumption across the globe is increasing at an alarming rate. This has already shown its impact in the depletion of energy sources and environmental issues (global warming, and weakening of the ozone layer). Certainly, this escalating tendency of energy insufficiency will get aggravated in the future. Efficiency enhancement initiatives are considered to be the key solution in reducing ...
consumer surplus; consumers (people); economic incentives; electricity; energy; financial economics; game theory; heat; issues and policy; markets; models; prices; profit maximization; social benefit
Abstract:
... We model the economic incentives for market participants to cooperate in the development of a microgrid in a small electricity network served by a regulated utility. The microgrid can provide energy, ancillary services, heat and enhanced reliability to its customers. Using the framework of cooperative game theory, assuming exchangeable utility and full public information, we quantify how microgrid ...
... The economic feasibility of Biomass District Heating (BDH) networks in rural villages is largely unknown. A cost-effective evaluation tool is developed to examine the feasibility of BDH in rural communities using secondary data sources. The approach is unique in that it accounts for all the major capital expenses: energy center, distribution network, and energy transfer stations, as well as biomas ...
air; distillation; energy; heat; oxygen; temperature
Abstract:
... An advanced cryogenic air separation process for oxy-combustion is proposed, based on self-heat recuperation technology. In contrast to double columns in the conventional cryogenic air separation process, a single distillation column only is used in the proposed process. By using self-heat recuperation technology, the heat of N2 product gas from the top of the single distillation column is recircu ...
case studies; meteorological data; models; relative risk; vehicles (equipment); United Kingdom
Abstract:
... As the number of electric vehicles increases, the impact of their charging on distribution networks is being investigated using different load profiles. Due to the lack of real charging data, the majority of these load impact studies are making assumptions for the electric vehicle charging demand profiles. In this paper a two-step modelling framework was developed to extract the useful information ...
... This study investigates the feasibility of using a data-driven optimization approach to determine the coordinated control actions of wind turbines that maximize the total wind farm power production. Conventionally, for a given wind condition, an individual wind turbine maximizes its own power production without taking into consideration the conditions of other wind turbines. Under this greedy cont ...
... Despite all the acknowledged advantages in terms of environmental impact reduction, energy efficiency and noise reduction, the electric mobility market is below expectations. In fact, electric vehicles have limitations that pose several important challenges for achieving a sustainable mobility system: among them, the availability of an adequate charging infrastructure is recognized as a fundamenta ...
... Efficient operation of thermoelectric devices strongly relies on the thermal integration into the energy conversion system in which they operate. Effective thermal integration reduces the temperature differences between the thermoelectric module and its thermal reservoirs, allowing the system to operate more efficiently. This work proposes and experimentally demonstrates a topology optimization ap ...
... Biochar derived from orchid tree leaves is utilised as the fuel of a direct carbon solid oxide fuel cell (DC-SOFC), with yttrium stabilized zirconia (YSZ) as electrolyte and cermet of silver and gadolinium doped ceria (Ag-GDC) as the material of both cathode and anode, operating without any liquid medium or feeding gas. The performance of the DC-SOFC operated on the leaf char is higher than that o ...
algorithms; batteries; buildings; cost effectiveness; data collection; models; primary energy; renewable energy sources
Abstract:
... In the past few decades, extensive research has been conducted to develop operation and control strategy for smart buildings with the purpose of reducing energy consumption. Besides studying on single building, it is envisioned that the next generation buildings can freely connect with one another to share energy and exchange information in the context of smart grid. It was demonstrated that a net ...
... This paper presents a double-layer smart charging management algorithm (SCMA) for electric vehicles in working place parking lots considering smart grid concept. This model enables safe and controlled charging, which satisfies both power grid and drivers’ needs comprehensively. First level of SCMA controls each transformer power demand, transformer capacity, charging station status and the shortes ...
air conditioning; airports; energy conservation; exergy; heat; models
Abstract:
... Optimal control strategies have been increasingly developed in heating, ventilation and air conditioning (HVAC) systems. The commonly used evaluation method, which compares the system’s energy consumption under proposed strategy with that under its original control, has several limitations. A dual-benchmark based CPI (control-perfect index) evaluation method is presented to assess the operation of ...
adsorbents; adsorption; air; buildings; desiccants; durability; energy recovery; heat transfer; information exchange; mass transfer; models; molecular dynamics; silica gel; ventilation systems; wheels
Abstract:
... Desiccant wheels have been extensively used for energy recovery of ventilation air from buildings. Performance of these wheels is influenced by many factors like the material properties, wheel matrix structures, operating conditions and fluid parameters. Previous studies only involved the macro-scale heat and mass transfer in the wheels and the system performance, by neglecting the micro-scale pro ...
... The capacity degradation of the lithium ion battery should be well predicted during battery system design. Therefore, high-fidelity capacity degradation models that are suitable for the task of capacity prediction are required. This paper proposes a novel capacity degradation model that can simulate the degradation dynamics under varying working conditions for large-format lithium ion batteries. T ...
air temperature; capital; case studies; climate; condensers; heat; power plants; summer; winter
Abstract:
... Air-cooled condensers are widely used for Organic Rankine Cycle (ORC) power plants where cooling water is unavailable or too costly, but they are then vulnerable to changing ambient air temperatures especially in continental climates, where the air temperature difference between winter and summer can be over 40°C. A conventional ORC system using a single component working fluid has to be designed ...
computer software; energy; models; power plants; prediction; probability distribution; prognosis; renewable energy sources; turbines
Abstract:
... The increase in energy demand has led to expansion of renewable energy sources and their integration into a more diverse energy mix. Consequently the operation of thermal power plants, which are spearheaded by the gas turbine technology, has been affected. Gas turbines are now required to operate more flexible in grid supporting modes that include part-load and transient operations. Therefore, con ...
case studies; coal; coal industry; decision making; dynamic programming; economic development; environmental impact; environmental models; laws and regulations; mining; pollutants; China
Abstract:
... Coal is the widespread fossil fuel on earth. It provides the necessary material foundation for economic development of a country. However, coal mining activities cause a lot of environmental impacts that are hazardous to the health of citizens in mining regions and place costs on the government. According to government laws and regulations, coal mines should invest in related pollution treatment p ...
computer software; equations; process design; simulation models; vibration
Abstract:
... This paper presents a linearization of the dynamic equation for a free-piston engine generator (FPEG), and simplifies it to a one-degree forced vibration system with viscous damping. The analogy between a mass-spring damper and a FPEG system is expressed, and the solution to the vibration system is solved. The model was successfully validated with respect to experimental data obtained from a proto ...
ammonia; electricity; energy efficiency; fuel loading; greenhouse gas emissions; greenhouse gases; heat; hydrogen; industrial applications; life cycle assessment; models; natural gas; wind; wind power; China
Abstract:
... Microgrids provide a new energy paradigm with the benefits of higher energy supply reliability, lower greenhouse gas (GHG) emissions through a higher penetration of renewable sources, higher energy efficiencies through the use of local waste heat and the avoidance of losses in transmission and distribution. This study reports a life cycle assessment (LCA) of microgrids for an industry application ...
computer software; energy; finite element analysis; life cycle costing; models; policy analysis; prediction; solar collectors; South Korea
Abstract:
... This study aims to develop the four-node-based finite element model for estimating the techno-economic performance of the building-integrated photovoltaic blind (FEM4-nodeBIPB), which can be used by decision-maker in the early design phase. In developing the proposed model, this study uses various research methodologies such as energy simulation, finite element method, life cycle cost analysis, po ...
cadmium; case studies; cost effectiveness; electricity generation; environmental impact; environmental performance; greenhouse gas emissions; greenhouse gases; learning; life cycle assessment; pollution control; solar energy; supply chain; technological change; value added
Abstract:
... Accounting for technological changes and innovation is important when assessing the implications of rapidly-developing greenhouse gas (GHG) mitigation technologies. Technological learning curves have been commonly used as a tool to understand technological change as a function of cumulative production. Traditional learning curve approaches, however, do not distinguish the direct and upstream, supp ...
El Nino; biogas; case studies; climate change; climate models; developing countries; econometric models; expert opinion; greenhouse gas emissions; greenhouse gases; land use; natural gas; power generation; primary energy; road transportation; trade; Colombia
Abstract:
... This paper presents a modeling framework to address the energy, economy, emissions and land use nexus when exploiting bioenergy in developing countries. The modeling framework combines a qualitative and a quantitative element. The qualitative element integrates two components: (1) technology roadmapping to identify long-term technology targets through expert judgment and (2) scenario analysis to i ...
... This paper presents a generalized model for wind turbine (WT) anomaly identification based on the data collected from wind farm supervisory control and data acquisition (SCADA) system. Neural networks (NNs) are used to establish prediction models of the WT condition parameters that are dependent on environmental conditions such as ambient temperature and wind speed. Input parameters of the predict ...
... At any particular moment, the energy security of an energy system is at risk from events, both external and internal, that can affect its operation. By analyzing these risks, the state of the system’s energy security can be determined. If the method is generic, it can be applied to any energy system and the entities that support its operation. Despite the potential benefits of such a method, a rev ...
batteries; electric vehicles; energy; friction; gears; heat; renewable energy sources; roughness; vibration
Abstract:
... The energy source of vehicles is changing rapidly and significantly in recent years with the increase in renewable energy technologies especially in the case of electric vehicles (EVs). A smart solution has emerged in which the wasted energy in a vehicle’s shock absorber is converted to an alternative energy for the cars themselves, and this is called an energy regenerative shock absorber. Whereas ...
... Increasing the performance of vanadium redox flow batteries (VRFBs), especially the energy efficiency and power density, is critically important to reduce the system cost to a level for widespread commercialization. Unlike conventional VRFBs with flow-through structure, in this work we create a VRFB featuring a flow-field structure with a carbon nanoparticle-decorated graphite felt electrode for t ...
energy conversion; models; water power; water waves; wind; Red Sea
Abstract:
... This study presents an assessment of the potential for harvesting wind and wave energy from the Red Sea based on an 18-year high-resolution regional atmospheric reanalysis recently generated using the Advanced Weather Research Forecasting model. This model was initialized with ERA-Interim global data and the Red Sea reanalysis was generated using a cyclic three-dimensional variational approach ass ...
Monte Carlo method; algorithms; buildings; electricity; energy balance; issues and policy; monitoring; prediction; renewable energy sources
Abstract:
... Employing a hybrid Genetic Algorithm (GA) and Monte Carlo (MC) simulation approach, energy consumption and renewable energy generation in a cluster of Net Zero Energy Buildings (NZEBs) was thoroughly investigated with hourly simulation. Moreover, the cumulative energy consumption and generation of the whole cluster and each individual building within the simulation space were accurately monitored ...
... HEV market penetration exists in a circular loop of purchase, use, retirement, and repurchase, i.e., the consumer ownership cycle. Existing HEV market penetration models focus on a single linear process, such as purchasing, without considering other processes. Market penetration policies based on such models can facilitate a single process, but they cannot boost market penetration as planned. Comb ...
algorithms; batteries; energy; generators (equipment); models; mutation; photovoltaic cells; solar collectors; system optimization; wind turbines
Abstract:
... With constructions of demonstrative microgrids, the realistic optimal economic dispatch and energy management system are required eagerly. However, most current works usually give some simplifications on the modeling of microgrids. This paper presents an optimal day-ahead scheduling model for a microgrid system with photovoltaic cells, wind turbine units, diesel generators and battery storage syst ...
energy efficiency; heteroskedasticity; models; power plants; regression analysis; China
Abstract:
... A new hybrid methodology is introduced which is a combination of multiple regression model and generalised autoregressive conditional heteroskedasticity (GARCH) model. Comparing the new approach and the vector auto-regression (VAR) model, this paper analyses the short-term dynamics of the energy efficiency index (EEI) in response to change in the five indicator variables for thermal power plants i ...
... Because of the limited resources of micro-controller, rule-based energy management strategies are still very popular for online control of plug-in hybrid electric vehicles, however, the control results may deviate from the optimal control results. Since the city bus routes are predetermined, the speed profiles of the certain bus route do not make much difference, this indeed creates an opportunity ...
case studies; consumers (people); energy; linear programming; market prices; markets; models; renewable energy sources; Europe
Abstract:
... A linear programming framework is proposed to model distribution network characteristics, and market clearing processes for flexible load and distributed energy resources providing reserve and reactive power compensation. One shows that the Nash equilibrium solution representing the interaction between utility and customers for demand response and distributed reserve transactions can be approximat ...
... Biodiesel was synthesized from waste frying oil (WFO) using β-potassium dizirconate (β-K2Zr2O5) as a novel heterogeneous catalyst. Synthesized catalyst was characterized by X-ray diffractometry (XRD), thermogravimetric analysis (TGA), attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR), particle size analyser, scanning electron microscopy (SEM), BET surface area and bas ...
decision making; energy; energy resources; markets; models; power plants; prices; risk
Abstract:
... Within a medium-term market horizon, this research work provides a methodology that allows a commercial virtual power plant (CVPP) to form an optimal coalition of heterogeneous distributed energy resources (DERs) based on weekly bilateral contracting, futures-market involvement, and pool participation. The established model aims at composing an optimal portfolio of available DERs and jointly takes ...
case studies; data collection; heat; models; power plants; system optimization
Abstract:
... This paper presents a novel, simple method for reducing external operating condition datasets to be used in multi-generation system optimization models. The method, called the Characteristic Operating Pattern (CHOP) method, is a visually-based aggregation method that clusters reference data based on parameter values rather than time of occurrence, thereby preserving important information on short- ...
computer software; mathematics and statistics; solar collectors; urban areas
Abstract:
... The standard mathematical approach used to calculate photovoltaic (PV) array spacing contains a number of assumptions that limits its use to PV arrays installed on horizontal surfaces. This paper utilises vector analysis to develop a new method to calculate array spacing and potential system size for any combination of PV array and surface tilt and orientation. This approach is validated by compar ...
case studies; commercialization; prices; subsidies; time series analysis; traffic; vehicles (equipment)
Abstract:
... The electrification of the transportation sector through the introduction of electric vehicles (EV) has recently emerged as a remedy to environmental and economic concerns. For this reason, governments around the world have been offering subsidies and other benefits to drivers that replace their conventional vehicle with an EV in order to facilitate the commercialization of the latter. However, wh ...
business enterprises; economic indicators; electric energy consumption; gas turbine engines; generators (equipment); market analysis; markets; politics; population distribution; power generation; risk assessment; solar thermal energy; uncertainty
Abstract:
... This paper presents an innovative methodology to perform market analysis of a new solar power generation technology based on parabolic dish and micro gas turbine engines. Technical, economic, social and political parameters of influence are combined together into a single figure of merit: index of market potential. This index is an original approach enabling the identification of the potential mar ...
case studies; electricity; energy; issues and policy; linear programming; markets; models; planning; prices; Crete
Abstract:
... This paper presents a generic Mixed Integer Linear Programming (MILP) model that integrates a Mid-term Energy Planning (MEP) model, which implements generation and transmission system planning at a yearly level, with a Unit Commitment (UC) model, which performs the simulation of the Day-Ahead Electricity Market. The applicability of the proposed model is illustrated in a case study of the Greek in ...
absorption; carbon dioxide; case studies; cold treatment; electric power; energy content; energy use and consumption; greenhouse gas emissions; heat pumps; heat recovery; linear programming; models; temperature; thermal energy; utilities; wastes
Abstract:
... Thermodynamic cycles such as organic Rankine cycles, absorption chillers, absorption heat pumps, absorption heat transformers, and mechanical heat pumps are able to utilize wasted thermal energy in process sites for the generation of electrical power, chilling and heat at a higher temperature. In this work, a novel systematic framework is presented for optimal integration of these technologies in ...
... This paper presents the development of a numerical model of a hybrid cooler for transient simulation purposes as a component of a thermal energy system. The model uses a modular definition of the control volume, and is suitable for modelling any staggered coil geometry. The set of parameters required for modelling the hybrid cooler is typical of the so-called design models. A rigorous analysis of ...
air; biodiesel; carbon; compliance; credit; diesel fuel; energy policy; markets; mixing; models; prices; California
Abstract:
... Biofuel policy is under near constant review at both the federal and state level. For example, as part of on-going implementation of the California Low Carbon Fuel Standard (LCFS), the California Air Resources Board has recently designed and is implementing a new cost containment mechanism as part of the compliance credit market embedded within the LCFS. This mechanism was born out of concerns tha ...
... A major aim of Capacity Remuneration Mechanisms (CRMs) is to lead the power system expansion towards the level of security of supply that the regulator considers adequate. When introducing a capacity mechanism, therefore, regulators must ensure that the resulting mix will actually provide the firmness pursued, in such a way that both the generation and the demand resources awarded with the capacit ...
... China has set ambitious goals for the development of offshore wind energy to meet the increasing energy demand of coastal provinces. Many studies have assessed the potential offshore wind energy in Chinese territorial waters. However, few studies have focused on the climatology, variability, and extreme climate of wind speeds and wind power, especially at hub height in this area. This type of stud ...
... Reverse cycle defrosting is the most widely used standard defrosting method for air source heat pump (ASHP) units. It was suggested in previous experimental studies that downwards flowing of the melted frost over a vertical multi-circuit outdoor coil in an ASHP unit has negative effects on reverse cycle defrosting performance. To quantitatively study the negative effects, an experimental study and ...
algorithms; case studies; issues and policy; models; prices; renewable energy sources; vehicles (equipment)
Abstract:
... This paper presents a decentralized scheduling algorithm for electric vehicles charging. The charging control model follows the architecture of a Multi-Agent System (MAS). The MAS consists of an Electric Vehicle (EV)/Distributed Generation (DG) aggregator agent and “Responsive” or “Unresponsive” EV agents. The EV/DG aggregator agent is responsible to maximize the aggregator’s profit by designing t ...
automobiles; biofuels; capital; carbon dioxide; decision making; electric vehicles; electricity; electricity generation; environmental impact; gasoline; greenhouse gas emissions; mixing; natural gas; oils; operating costs; petroleum; primary energy; transportation; Brazil; China; France; Italy; United States
Abstract:
... This paper proposes an exergy-based well-to-wheels analysis to compare different passenger vehicles, based on three key indicators: petroleum energy use, CO2 emissions, and economic cost. A set of fuel pathways, including petroleum-based fuels, compressed natural gas, biofuels, and electricity are considered in five representative national energy mixes, namely Brazil, China, France, Italy, and the ...
algorithms; case studies; computer techniques; energy; linear programming; models; vehicles (equipment)
Abstract:
... In this paper, a multi-objective framework is proposed for the daily operation of a Smart Grid (SG) with high penetration of sensitive loads. The Virtual Power Player (VPP) manages the day-ahead energy resource scheduling in the smart grid, considering the intensive use of Distributed Generation (DG) and Vehicle-To-Grid (V2G), while maintaining a highly reliable power for the sensitive loads. This ...
algorithms; coal; energy; gasification; power plants; probability distribution; uncertainty
Abstract:
... Integrated Gasification Combined Cycle (IGCC) power plants provide a cleaner and more efficient way to obtain energy from coal. In order to operate an IGCC power plant in a safe and stable manner, several input and output process parameters need to be monitored. However, due to economic and operational constraints, it is infeasible to place sensors at every input and output process parameter locat ...
biodiversity; carbon; case studies; cost effectiveness; crop yield; emissions; energy industry; fuels; human health; land use; linear programming; models; planning; power generation; power plants; sustainable development; China
Abstract:
... The negative externalities apart from carbon emissions are often neglected in most power generation planning models, which will affect the human health, biodiversity, crop yield and land use greatly. To achieve a sustainable development of China’s power industry, this paper develops a deterministic linear programming model with consideration of the non-carbon externalities. This model has been app ...
energy; models; new markets; operating costs; pollution
Abstract:
... The increased presence of variable renewable generation drives a greater need for authorities to procure more ancillary services (AS) for grid balance. One of these services is contingency reserve (CR), which is used to regulate the grid frequency in contingencies. Many Independent System Operators (ISO) are structuring the rules of AS markets such that demand response (DR) can participate along s ...
anaerobic digestion; decision making; embodied energy; energy efficiency; energy requirements; environmental impact; life cycle assessment; material flow analysis; models; planning; production technology; renewable energy sources; temporal variation
Abstract:
... A transparent and comparable understanding of the energy efficiency, carbon footprint, and environmental impacts of renewable resources are required in the decision making and planning process towards a more sustainable energy system. Therefore, a new approach is proposed for measuring the environmental sustainability of anaerobic digestion green gas production pathways. The approach is based on t ...
filters; fuzzy logic; model validation; neural networks; solar radiation; wavelet
Abstract:
... The performance of solar radiation models is evaluated based on time domain statistical metrics. These metrics include root mean square error (RMSE), mean absolute percentage error (MAPE) and coefficient of determination (R2). However, this study adopts a new approach to model validation in phase and frequency domains. The study proposes frequency coherence and phase synchronization methods quanti ...
energy balance; heat exchangers; models; seasonal variation; soil density; soil temperature; specific heat; summer; winter
Abstract:
... This paper presents a new approach to considering the effect of seasonal changes in soil temperature on the performance of a horizontal geo heat exchanger. It is different from extant models which consider the seasonal changes in soil temperature by applying a real energy balance on the ground surface. In the new model, the seasonal changes in soil temperature, which are affected by the thermal in ...
batch systems; distillation; energy; energy conservation; entropy; heat; heat pumps; issues and policy
Abstract:
... This work introduces a new heat integrated distillation column (HIDiC) for batch processing. Under this scheme, the entire cylindrical shell is proposed to divide vertically by a metal wall into two closed semi-cylinders. Aiming to generate an internal heat source, a heat pump system is employed over the left hand division to elevate the pressure of the right hand part with the application of HIDi ...
... Passive solar houses are effective solutions for minimizing the operating energy of buildings. The building envelopes of passive solar houses exert a significant influence on the degree of indoor thermal comfort. The focus of this study was the construction of high-performance opaque envelopes, i.e., the roof and walls, for a passive solar house, and a new conception of the envelopes from the pers ...
calcium; calcium oxide; carbon dioxide; carbonation; coal; energy costs; energy efficiency; limestone; models; power plants; temperature; toxicity
Abstract:
... The Ca-Looping (CaL) process is at the root of a promising 2nd generation technology for post-combustion CO2 capture at coal fired power plants. The process is based on the reversible and quick carbonation/calcination reaction of CaO/CaCO3 at high temperatures and allows using low cost, widely available and non toxic CaO precursors such as natural limestone. In this work, the efficiency penalty c ...
algorithms; energy; infrastructure; linear programming; wind farms; wind turbines
Abstract:
... Internal electrical networks of large wind farms constitute complex and dispersed grid structures. Wind turbines are scattered over vast areas and the total length of cabling infrastructure might reach several dozens of kilometers. Outlays related to cable laying significantly contribute to the entire project budget. Therefore the design process should minimize these expenses considering also oper ...
electric power; energy; markets; models; system optimization
Abstract:
... Transmission congestion management plays a key role in deregulated energy markets. To correctly model and solve this problem, power system voltage and transient stability limits should be considered to avoid obtaining a vulnerable power system with low stability margins. Congestion management is modeled as a multi-objective optimization problem in this paper. The proposed scheme includes the cost ...
... This work introduces a new predictive multi-zone model for the description of combustion in Homogeneous Charge Compression Ignition (HCCI) engines. The model exploits the existing OpenSMOKE++ computational suite to handle detailed kinetic mechanisms, providing reliable predictions of the in-cylinder auto-ignition processes. All the elements with a significant impact on the combustion performances ...
air; carbon dioxide; cold; cooling; energy; evaporation; humidity; natural gas; power plants; temperature
Abstract:
... A novel liquefied natural gas (LNG) cryogenic energy utilization method for gas turbine inlet air cooling is proposed in this work. In this method, the temperature difference potential between LNG and cooling medium is utilized step by step. The novel cold production process consists of a CO2 Rankine cycle subsystem and a CO2 compression–refrigeration subsystem. A sensitivity analysis is performed ...
batteries; decision making; electricity; energy; equations; renewable energy sources; solar collectors; wind; wind turbines
Abstract:
... A new approach for optimal combinations of Hybrid Renewable Energy Systems (HRESs) is proposed, for diesel-free remote communities and related decision-making problems. The objective of the design is to satisfy the load with total cost’s minimization considering related constraints, where all analytical equations are given. The proposed system is a DC configuration for renewable energy integration ...
... With the increasing presence of intermittent renewable energy generation sources, variable control over loads and energy storage devices on the grid become even more important to maintain this balance. Increasing renewable energy penetration depends on both technical and economic factors. Distribution system consumers can contribute to grid stability by controlling residential electrical device po ...
algorithms; models; time series analysis; wind farms; wind power
Abstract:
... A novel bidirectional mechanism and a backward forecasting model based on extreme learning machine (ELM) are proposed to address the issue of ultra-short term wind power time series forecasting. The backward forecasting model consists of a backward ELM network and an optimization algorithm. The reverse time series is generated to train backward ELM, assuming that the value to be forecasted is alre ...
air; air conditioning; air flow; blowers; desiccants; desorption; heat; models; relative humidity; silica gel; surface area; temperature; wheels; United Kingdom
Abstract:
... Rotary desiccant wheels are used to regulate the relative humidity of airstreams. These are commonly integrated into Heating, Ventilation and Air-Conditioning units to reduce the relative humidity of incoming ventilation air. To maximise the surface area, desiccant materials are arranged in a honeycomb matrix structure which results in a high pressure drop across the device requiring fans and blow ...
deformation; electricity; electrons; energy conversion; harvesting; hydrocolloids; power generation; vibration
Abstract:
... In this paper, a novel energy conversion method based on hydrogel material for self-powered sensor system applications is proposed, which can harvest energy from environment vibrations and supply power to sensors without any external power source. In this approach, hemispherical hydrogel arrays are positioned between two parallel-arranged conductive plates. The deformation of hydrogel arrays cause ...
... Smart grid is a platform that enables the participants of electricity market to adjust their bidding strategies based on Demand-Side Management (DSM) models. Responsiveness of the market participants can improve reliability of system operation as well as capital cost investments. In this regard, the accurate forecast of electricity price and demand in smart grids is an important challenge as their ...
air; air temperature; ambient temperature; axial flow fans; condensers; mass flow; power plants; wind; wind power
Abstract:
... Ambient winds are generally unfavorable to the thermo-flow performances of air-cooled condensers in power plants. More emphases are placed to weaken the negative effects of ambient winds, but no layout alternative of air-cooled condensers is considered. In this work, a novel vertical arrangement of air-cooled condensers is proposed on the basis of a 2×600MW direct dry cooling power plant, which ca ...
air; case studies; combustion; compressors; computer software; energy; energy use and consumption; mathematical models; turbines
Abstract:
... In this work, a novel detailed mathematical model for the performance assessment of diabatic compressed air energy storage (D-CAES) systems with underground storage site is proposed. The model was implemented in Matlab environment and it was validated using the D-CAES Huntorf plant data, demonstrating a close agreement with the data reported in literature. The analysis of some case studies of the ...
European Union; Monte Carlo method; artificial intelligence; case studies; data collection; energy conservation; energy efficiency; health services; normal values; statistical models; Italy
Abstract:
... The current EU energy efficiency directive 2012/27/EU defines the existing building stocks as one of the most promising potential sector for achieving energy saving. Robust methodologies aimed to quantify the potential reduction of energy consumption for large building stocks need to be developed. To this purpose, a benchmarking analysis is necessary in order to support public planners in determin ...
Chuan Zhang; Li Zhou; Pulkit Chhabra; Sushant S. Garud; Kevin Aditya; Alessandro Romagnoli; Gabriele Comodi; Fabio Dal Magro; Antonella Meneghetti; Markus Kraft
case studies; energy efficiency; greenhouse gas emissions; heat; industry; information sources; system optimization; transportation; Singapore
Abstract:
... Based on share of energy, materials, resources and information, Eco Industrial Park (EIP) has become a popular form of industry cluster. Waste Heat Recovery (WHR) in EIP can significantly increase the total energy efficiency of the whole park, meanwhile reducing its greenhouse gas emission. The current paper proposes a methodology to assess the opportunities of WHR in EIP at park level. Four diffe ...
... Due to the strong nonlinearity and complex time-variant property of batteries, the existing state of charge (SOC) estimation approaches based on a single equivalent circuit model (ECM) cannot provide the accurate SOC for the entire discharging period. This paper aims to present a novel SOC estimation approach based on a multiple ECMs fusion method for improving the practical application performanc ...