There are two primary ways to save energy within a building: (1) through improving building engineering structures and adopting efficient appliance ownership, and (2) through changing occupants’ energy-consuming behaviors. Unfortunately the second way suffers from many challenges and limitations. Occupant behavior is, indeed, a complex and multi-disciplinary concept depending on several human factors. Although its importance is recognized by the energy management community, it is often oversimplified and naively defined when used to study, analyze or model energy load. This paper aims at promoting the definition of occupant behavior as well as exploring the extent to which the latter is involved in research works, targeting directly or indirectly energy savings. Hence, in this work, we propose an overview of interdisciplinary research approaches that consider occupants’ energy-saving behaviors, while we present the big picture and evaluate how occupant behavior is defined, we also prop... [more]

Prediction of pollutant emissions is a key aspect of modern combustor design in energy conversion systems. In the presented work, a simple and robust model based on low-order reaction networks is applied to a FLOX® laboratory combustor at atmospheric conditions. The applied approach is computationally cheap and therefore highly suited for design studies. Steady-state CFD RANS simulations are carried out, serving as a basis for the network generation algorithm. CFD results are validated with experimental data for flow field and combustion. Different degrees of fidelity of reactor network models are taken into consideration and findings are opposed to measurements, evaluating the quality of the low-fidelity models. Validation of CO and NOx emission results of reactor network modeling provides accurate qualitative and quantitative reproduction of experimental findings, depending on the degree of heat loss applied on the combustion system. The introduced approach is therefore readily appli... [more]

In recent years climate change has emerged as a global issue directly related to quality of life. In this context, one of the key goals in the next few decades will be to transition the global economy to a sustainable system. The nature of the energy planning process dictates the application of complex models. There is no universal solution to the energy planning problem. Each territory requires a bespoke strategy aimed at utilising its specific potential. The research presented in this paper explores reaching a zero-carbon energy system at the city level. It establishes a step-by-step decarbonisation method and proposes an energy transition index (ETI). The index presented is used to evaluate different renewable energy sources (RES) deployment scenarios in the context of affordability, self-reliance, and sustainability. The main aspects and barriers of deploying sustainable energy solutions are also explored. Some of the key challenges of RES deployment are identified as capital inten... [more]

Reserves totaling ~142 BCM (5 TCF) of natural gas trapped in 306 fields and ~22 MTOE (~157 MMBOE) of crude oil in 87 fields have been discovered. The prospection, exploration, and production of hydrocarbons are licensed: an entity interested in these kinds of activities needs to have concession, which is granted by the Polish Ministry of Climate and Environment for 10 to 30 years according to one of two independent ways—international tender or open door procedure. In this review, the most prospective areas for oil and gas exploration in Poland, selected by the Polish Geological Survey, and announced as dedicated for the next 6th tender round, planned in the second half of 2022, are described. These are: Block 413−414, Block 208, Cybinka−Torzym, Zielona Góra West, and Koło areas. The main exploration target of these tender areas is related to conventional and unconventional accumulations of gas and oil in the Carpathian basement, Carpathian Foredeep, and Outer Carpathians (Block 413−414... [more]

The accurate prediction of the solar energy that can be generated using the rooftops of buildings is an essential tool for many researchers, decision makers, and investors for creating sustainable cities and societies. This study is focused on the development of an automated method to extract the useable areas of rooftops and optimize the solar PV panel layout based on the given electricity loading of a building. In this context, the authors of this article developed two crucial methods. First, a special pixel-based rooftop recognition methodology was developed to analyze detailed and complex rooftop types while avoiding the challenges associated with the nature of the particular building rooftops. Second, a multi-objective enveloped min−max optimization algorithm was developed to maximize solar energy generation and minimize energy cost in terms of payback based on the marginal price signals. This optimization algorithm facilitates the optimal integration of three controlled variables... [more]

Energy efficiency through energy saving is a key trend in the modern world. Analyses have been conducted by scientists in different fields on various target groups that influence sustainable energy consumption. The aim of the research presented in this article is to determine the association between parental attitudes and awareness of sustainable energy consumption in the perception of young people with ASD (13−17 years old). This was a pilot study. The diagnostic-survey method was used, along with The Scale of Parental Attitudes by M. Plopa and an authored survey questionnaire. Deliberate random sampling was applied. A statistical analysis showed a relationship between the acceptance attitude of both parents and the autonomy attitude of one parent—the father—and awareness of sustainable energy consumption among young people with Autistic Spectrum Disorder (ASD). In addition, a critical literature review confirmed the necessity of combining energy awareness and financial awareness, as... [more]

The main purpose of this paper is to evaluate the overall performance of a battery energy storage system (BESS) during (I) grid-connected, (II) black start, and (III) islanded operating modes. To do so, firstly, a novel three-mode controller is proposed and developed. The proportional−integral−derivative (PID) controller is implemented, including the following three components: (1) inertia emulation, (2) frequency-active power and voltage-reactive power droops, and (3) secondary frequency and voltage controllers. Secondly, to effectively evaluate the proposed controller performance under various grid operating conditions during both black start and seamless transition to islanded operation, a set of comprehensive dynamic simulations using Matlab/Simulink is carried out. To this end, the sensitivity analyses on numerous grid operating parameters, such as pre-disturbance grid power, total installed BESS capacity, battery state of charge, unbalanced three-phase load flows, implemented pow... [more]

In this paper, the 12-slot/4-pole (12/4) synchronous reluctance motor (SynRM) with concentrated windings is proposed for low-cost hybrid vehicles. The non-linear magnetic equivalent circuit (MEC) model of the 12/4 SynRM is built to obtain the main electromagnetic characteristics such as coil flux, inductances, torque, etc. The magnetic saturation is also counted in by the MEC. Results calculated by MEC are validated by 2D finite element analysis (FEA). Then, aiming at larger average torque, lower torque ripple and lower total harmonic distortion (THD) in phase voltage, the parameter optimization method of the SynRM is proposed based on the Taguchi method and the MEC model. The proposed Taguchi-MEC method enables a fast optimization with satisfactory accuracy. Finally, the motor prototype is manufactured, and experimental validations are carried out.

A sustainable nexus between renewable energy production and plastic abatement is imperative for overall sustainable development. In this regard, this study aims to develop a cheaper and environmentally friendly nexus between plastic waste management, wastewater treatment, and renewable hydrogen production. Fluorescent carbon (FCs) were synthesized from commonly used LDPE (low-density polyethylene) by a facile hydrothermal approach. Optical absorption study revealed an absorption edge around 300 nm and two emission bands at 430 and 470 nm. The morphological analysis showed two different patterns of FCs, a thin sheet with 2D morphology and elongated particles. The sheet-shaped particles are 0.5 μm in size, while as for elongated structures, the size varies from 0.5 to 1 μm. The as-synthesized FCs were used for the detection of metal ions (reference as Cu2+ ions) in water. The fluorescence intensity of FCs versus Cu2+ ions depicts its upright analytical ability with a limit of detection (... [more]

Rule-based systems, which are the typical technology used to realize context-aware services, have been independently implemented in various smart services. The challenges of these systems are the versatility of action, looseness, and the coding that is needed to describe the conditional branches. The purpose of this study was to support the realization of service coordination and smart services using context-aware technology by converting rule-based systems into services. In the proposed method, we designed and implemented the architecture of a new service: Unified Rule-Based Message Delivery Service (Uni-messe), which is an application-neutral rule management and evaluation service for rule-based systems. The core part of the Uni-messe proposal is the combination of a Pub/Sub and a rule-based system, and the proposal of a new event−condition−route (ECR) rule-based system. We applied Uni-messe to an audio information presentation system (ALPS) and indoor location sensing technology to... [more]

The high integration of power information physical system improves the efficiency of power transmission, but it also brings new threats to power grid. False data injection attacks can use traditional bad data to detect vulnerabilities and maliciously tamper with measurement data to affect the state estimation results. In order to achieve a higher security level for power systems, we propose an earth mover distance method to detect false data injection attacks in smart grids. The proposed method is built on the dynamic correlation of measurement data between adjacent moments. Firstly, a joint-image-transformation-based scheme is proposed to preprocess the measurement data variation, so that the distribution characteristics of measurement data variation are more significant. Secondly, the deviation between the probability distribution of measurement data variation and the histogram are obtained based on the earth’s mover distance. Finally, a reasonable detection threshold is selected to... [more]

This work investigates potential cost reduction trajectories of three emerging offshore renewable energy technologies (floating offshore wind, tidal stream, and wave) with respect to meeting ambitious cost targets set out in the Strategic Energy Technology Implementation Plans (SET-Plans) for Offshore Wind and Ocean Energy. A methodology is presented which calculates target costs for current early-stage devices, starting from the 2030 SET-Plan levelised cost targets. Component-based experience curves have been applied as part of the methodology, characterised through the comparative maturity level of each technology-specific cost centre. The resultant early-stage target costs are then compared with actual costs for current devices to highlight where further cost reduction is still required. It has been found that innovation and development requirements to reach these targets vary greatly between different technologies, based on their current level of technological maturity. Future fund... [more]

Worldwide, the use of fossil fuels covers almost 80% of the entire energy needs. In the European Union (EU), 2020 represents a watershed: for the first time, renewables were the main source of electricity. In Italy, the latest surveys demonstrate an increase in the use of alternative energy sources. European legislative framework highlights the importance of these new trends encouraging (and imposing) the use of renewables. The necessity to become more proactive in the energy production−consumption process and in the achievement of sustainability targets brings people to create Energy Communities (ECs) to manage their own energy supply chain. The authors present an overview of the main legislative framework in the EU and Italy in relation to ECs, analyzing the energy consumption, the electricity and heat energy production potentiality, and the energy balance in a portion of an Italian middle-size city in the Milan metropolitan area. Moreover, they underline the technical, regulatory, a... [more]

Nuclear power plants are required to maintain operation after an earthquake, leading to a safe shutdown if necessary. In the case of a loss of offsite power, the onsite emergency diesel generator is critical to ensure procedural operations of the nuclear power plant. As a means to reduce the overall seismic risk, a three-dimensional seismic protection system is proposed to enhance the seismic performance of the emergency diesel generator. The proposed seismic isolation system decouples the horizontal and vertical components of shaking and considers available hardware to achieve an effective isolation solution over the range of excitation frequencies considered. Numerical analysis of the proposed system demonstrates a reduction in seismic demands on the emergency diesel generator and provides a higher safety margin than conventional base installation procedures. Umbilical lines that cross the isolation plane are considered and impose additional constraints on the displacement capacity o... [more]

Recent years have seen an increase in the role of social media in the communication of energy sector companies (ESCs) with consumers. Currently, consumers look for information, create it themselves, and share it with other Internet users. eWOM communication means that energy companies, firstly, must be present in social media so that consumers can get to know them better, and secondly, they must consciously shape their image according to the expectations of their customers. One-way communication, such as customer satisfaction measurements, is no longer enough to know their preferences. Market trends indicate that for current buyers—both consumer and non-consumer products—the image of a “green product” or a “green company” is expected. Only a few companies report that they are harmful for environment. All companies report that they are generally community friendly. The consumer would like to know, in particular, about the harmfulness to the environment. Thus, there is a knowledge gap th... [more]

Bulk materials are necessary for hydropower construction. The bulk materials transportation (BMT) scheme is a guiding document for material supply, and its selection has a significant influence on hydropower construction. Since the BMT problem includes transportation planning and scheme selection issues simultaneously, only a small number of studies have focused on it. This paper presents a theoretical two-stage decision-making method (TDM), which innovatively combines the path optimization method and the multi-criteria decision-making (MCDM) method to solve the BMT problem. In the first stage, a multi-source path optimization model is established to optimize the transportation network and obtain a set of alternatives from each supply point to the construction site. In the second stage, considering the factors of economy, risk and construction progress, the MCDM method is adopted to select the optimal scheme from the alternatives. In addition, web crawler technology is used to obtain t... [more]

Wax deposition and gelation of waxy crude oil in production pipelines are detrimental to crude oil transportation from offshore fields. A waxy crude oil forms intra-gel voids in pipelines under cooling mode, particularly below the pour point temperature. Consequently, intrusion of non-reacting gas into production pipelines has become a promising method to lessen the restart pressure required and clear the clogged gel. A trial-and-error method is currently employed to determine the required restart pressure and restart time in response to injected gas volume. However, this method is not always accurate and requires expert knowledge. In this study, predictive models based on an Artificial Neural Network (ANN) and multilinear regression are developed to predict restart pressure and time as a function of seabed temperature and non-reacting gas injected volume. The models’ outcomes are compared against experimental results available from the literature. The empirical models predicted the re... [more]

It is imperative to use clean energy in order to achieve “carbon neutrality” and “carbon peaking”. This research aims to explore the impact of the agricultural mechanization level, the rural infrastructure construction level, and the rural economic development level on the utilization of high-quality straw energy, and, resultingly, this study aims to help provide suggestions for promoting high-quality straw energy utilization, develop the potential of high-quality straw energy, and alleviate China’s energy shortage problem. This paper develops a measurement model using the ridge regression model with panel fixed effects, which overcomes the multi-collinearity problem among the various factors influencing the utilization of high-quality energy from straw. Panel data from 24 provinces and cities, from 2009 to 2017, are used. The results show that the improvements of the agricultural mechanization level, the rural infrastructure construction level, and the rural economic development level... [more]

Permanent magnet (PM) excited vernier machines capable of high torque density have good potential for electric vehicles while requiring high rare earth PM consumption. To achieve a high torque density at a reasonable material cost, hybrid PM excited vernier machines incorporating both expensive rare earth and low-cost ferrite magnets are investigated in this paper. Various combinations of PM arrangements for the hybrid permanent magnet excited vernier machine are investigated to acquire low cost and superior torque density. The best solution obtained is that the PM on the stator adopts rare earth material while the rotor uses ferrite. Furthermore, the PMs on the stator are arranged in an iron-cored Halbach array, which can reduce leakage flux and enhance flux density effectively and the ferrite PMs are used in the rotor, therefore, high-temperature demagnetization is avoided. Then, the reluctance torque and the cogging torque can offset each other effectively, which is beneficial to re... [more]

The article presents the Power Hardware-In-the-Loop (PHIL) dynamic model of a synchronous generator of 125 kVA for autonomous power generation system analysis. This type of system is typically composed of electrical energy sources in the form of several diesel generator units with synchronous machines, the main distribution switchboard and different loads. In modern power distribution systems, the proposed power management strategies are typically aimed at the minimization of fuel consumption by maintaining the operation of diesel generator units at peak efficiency. In order to design and test such a system in conditions as close as possible to the real operating conditions, without constructing an actual power distribution system, a PHIL model in the form of a power inverter that emulates the behaviour of a real synchronous generator is proposed. The PHIL model was prepared in the MATLAB/Simulink environment, compiled to the C language and fed into a 150 kVA bidirectional DC/AC commer... [more]

A compound energy management strategy is proposed to improve the fuel cell’s durability and the economy of fuel cell hybrid electric vehicles (FCHEV). A control strategy that combines fuzzy control and switching control is proposed, taking into account factors that affect the fuel cell’s durability and the supercapacitor park’s safety. To smooth the output power of fuel cells under frequent variable load conditions, a moving average filtering algorithm has been added. Finally, co-simulation using Advisor and Matlab/Simulink under the World Light Vehicle Test Cycle (WLTC) compares the proposed strategy with fuzzy control and power following strategies. The experimental results show that the proposed strategy ensures the safety of the supercapacitor park and improves the durability of the fuel cell while improving the economy of the whole vehicle.

Series connection is an attractive approach to increase the blocking voltage of SiC power MOSFETs. Currently, the voltage balancing design of the series connection of the SiC MOSFETs highly relies on offline calibration and is challenging in the complex field operation. In this paper, a quantitative model to assess the voltage balancing performance is proposed to achieve a clear mathematical interpretation of the dynamic response of the voltage imbalance control loop. To begin with, an analytical model of the drain-source voltage rising time during the turn-off transient concerning the non-constant Miller plateau is proposed. Based on the turn-off model of the single device, the voltage imbalance sensitivity (VIS) is proposed to describe the influence of the parameters on the gate driving signals on the voltage imbalance. The VIS parameter can be easily achieved from the behavior of single devices, abandoning the complex variables in series connection. Further, for the typical case, ac... [more]

We investigated the shear banding phenomena in the non-isothermal simple-shear flow of a viscoelastic-fluid-based nanofluid (VFBN) subject to exothermic reactions. The polymeric (viscoelastic) behavior of the VFBN was modeled via the Giesekus constitutive equation, with appropriate adjustments to incorporate both the non-isothermal and nanoparticle effects. Nahme-type laws were employed to describe the temperature dependence of the VFBN viscosities and relaxation times. The Arrhenius theory was used for the modeling and incorporation of exothermic reactions. The VFBN was modeled as a single-phase homogeneous-mixture and, hence, the effects of the nanoparticles were based on the volume fraction parameter. Efficient numerical schemes based on semi-implicit finite-difference-methods were employed in MATLAB for the computational solution of the governing systems of partial differential equations. The fundamental fluid-dynamical and thermodynamical phenomena, such as shear banding, thermal... [more]

The global need to transition to renewable and decentralized systems entails agricultural systems as producers of residual biomass. Avocado trees (Persea americana Mill.) are one of the main woody crops cultivated in Mexico, with over 150,000 hectares grown in the country. The aim of the present study is to evaluate the use of avocado pruning residues as an energy input, focusing on the revalorization of biomass and the generation of economic benefits for small producers in the region. For that purpose, we developed allometric equations to calculate biomass availability from pruning residues, evaluated their thermochemical properties, and proposed technological alternatives for their energy use. Two allometric equations for pruning residues as a function of tree height and crown diameter were obtained: one for light and minor maintenance pruning (R2 = 0.63) and one for rejuvenation pruning (R2 = 0.86). From these equations, we estimate the mean amount of biomass generated from light an... [more]

Empirical-statistical downscaling (ESD) can be a computationally advantageous alternative to dynamical downscaling in representing a high-resolution regional climate. Two distinct strategies of ESD are employed here to reconstruct near-surface winds in a region of rugged terrain. ESD is used to reconstruct the innermost grid of a multiply nested mesoscale model framework for regional climate downscaling. An analog ensemble (AnEn) and a convolutional neural network (CNN) are compared in their ability to represent near-surface winds in the innermost grid in lieu of dynamical downscaling. Downscaling for a 30 year climatology of 10 m April winds is performed for southern MO, USA. Five years of training suffices for producing low mean absolute error and bias for both ESD techniques. However, root-mean-squared error is not significantly reduced by either scheme. In the case of the AnEn, this is due to a minority of cases not producing a satisfactory representation of high-resolution wind, a... [more]