Energies, Volume 14, Issue 4

Wind power generators face risks derived from fluctuations in market prices and variability in power production, generated by their high dependence on wind speed. These risks could be hedged using weather financial instruments. In this research, we d...

Exploitation of conventional energy resources has caused a deliberate increase in the emitted carbon in the atmosphere, which catalyzes global warming trends. This is a matter of concern, especially in Qatar, where fossil fuels (oil and gas) are larg...

The paper presents a new design solution for the multi-cylinder compressed air engine, described in the PL 216801 patent. A characteristic feature of the engine is its double-piston operation with pistons working in pairs in opposition and a reciproc...

This study aims to overview the U.S. sustainable development by measuring the environmental performance of 50 states over the period of 2009–2018. To attain the objective, we employ data envelopment analysis for environmental assessment where we prio...

The purpose of the study is to assess the efficiency of cash flow management at power supply companies of the CIS (Commonwealth of Independent States) countries. A methodological approach to cash flow forecasting with the use of linear and polynomial...

The paper proposes a coordinated frequency control strategy for Virtual Power Plant (VPPs), with the inclusion of Distributed Energy Resource (DERs), e.g., Solar Photo-Voltaic Generation (SPVG), Wind Generator (WG) as well as Energy Storage System (E...

Composting is the natural, exothermic process where the huge amount of heat that is created is an issue of organic matter decomposition. However, too high temperature can reduce the microbial activity during the thermophilic composting phase. The aim...

This paper deals with energy efficiency examined through an integrated model that links energy with environment, technology, and urbanisation as related areas. Our main goal is to discover how efficiently developed countries use primary energy and el...

In this study, a holistic energy, economic and environmental assessment was performed on a prosumer-based district heating system, including scenarios with varying district size, retrofitting stages and system configurations. A modeling framework was...

Early warning of a potential rockburst risk and its area of occurrence helps to take effective and targeted measures to mitigate rockburst hazards. This study investigates the microseismic (MS) spatial-temporal precursory characteristic parameters in...

Dielectric electroactive actuators are novel and significant smart actuators. The crucial aspect of construction of these devices is the bias mechanism. The current literature presents three main types of biases used in the construction of the DEAP a...

The need to reduce energy consumption in buildings is an urgent task. Increasing the use of calibrated building energy models (BEM) could accelerate this need. The calibration process of these models is a highly under-determined problem that normally...

The development of civilization, and subsequent increase in the number of new buildings, poses engineering problems which are progressively more difficult to solve, especially in the field of geotechnics and geoengineering. When designing new facilit...

The expansion of photovoltaics in German cities has so far fallen short of expectations. The concept of ‘tenant electricity’ (‘Mieterstrom’ in German), in which tenants of a building are supplied with solar power produced on site, offers great potent...

In wind energy site assessment, one major challenge is to represent both the local characteristics as well as general representation of the wind climate on site. Micro-scale models (e.g., Reynolds-Averaged-Navier-Stokes (RANS)) excel in the former, w...

Recently, biomass application as a renewable energy source is increasing worldwide. However, its availability differs in dependence on the location and climate, therefore, agricultural residues as cow dung (CD) are being considered to supply heat and...

Certified electric vehicle power converters can inject DC current into the AC grid if they fail. Verification of DC injection by electric vehicle supply equipment can be a cost-effective extra measure to ensure power quality from a variety of plugged...

The FlexPlan Horizon2020 project aims at establishing a new grid-planning methodology which considers the opportunity to introduce new storage and flexibility resources in electricity transmission and distribution grids as an alternative to building...

Proper management of solar energy as an effective renewable source is of high importance toward sustainable energy harvesting. This paper offers a novel sophisticated method for predicting solar irradiance (SIr) from environmental conditions. To this...

A comprehensive review of different thermal energy storage materials for concentrated solar power has been conducted. Fifteen candidates were selected due to their nature, thermophysical properties, and economic impact. Three key energy performance i...

This paper presents control strategies to activate energy flexibility for zones with radiant heating systems in response to changes in electricity prices. The focus is on zones with radiant floor heating systems for which the hydronic pipes are locat...

This article presents a modified sinusoidal pulse-width modulation (SPWM) scheme for a five-phase, three-level neutral-point-clamped inverter. The modulation scheme deploys a modified min–max function to inject the zero-sequence components into the r...

The dynamic of the world’s crude oil market has drastically changed over the last decade [...]

The Green Remodeling Project under South Korea’s Green New Deal policy is a government-led project intended to strengthen the performance sector directly correlated with energy performance among various elements of improvement applicable to building...

Quality of power supply in power distribution systems requires continuous measurement using power quality analyzers installed in the grid. The paper reviews the published methods for optimal location of metering points in distribution systems in the...

In smart cities, it is expected that transport, communication as well as the movement of people and goods will take place in the shortest possible time while maintaining a high level of safety. In recent years, due to the significant increase in the...

The Conservative Power Theory (CPT) emerged in recent decades as a theoretical framework for coping with harmonically distorted and unbalanced electric networks of ac power systems with a high participation of converter interfaced loads and generatio...

The degradation of lithium-ion cells with respect to increases of internal resistance (IR) has negative implications for rapid charging protocols, thermal management and power output of cells. Despite this, IR receives much less attention than capaci...

Modern electric vehicle heating, ventilation, and air-conditioning (HVAC) systems operate in more efficient heat pump mode, thus, improving the driving range under cold ambient conditions. Coupling those HVAC systems with novel heating technologies s...

Photovoltaic-thermal (PV/T) collectors have gained a lot of attention in recent years due to their substantial advantages as compared to ST or PV systems alone and even to other non-solar technologies. However, PV/Ts are still not as popular in indus...

Conventional constant speed turbo air centrifugal compressor systems (TACCSs) consist of an electric motor driven at the constant speed and an inlet guide vane (IGV) for pressure control. TACCSs with an inverter for a variable speed drive (VSD) of th...

This paper presents the first systematic comparison between south-facing monofacial and bifacial photovoltaic (PV) modules, as well as between south-facing bifacial and vertical east-west facing bifacial PV modules in Alaska. The state’s solar indust...

Due to problems related to environmental pollution and fossil fuels consumption that have not infinite availability, the automotive sector is increasingly moving towards electric powertrains. The most limiting aspect of this category of vehicles is c...

Ethiopia is a low-income country, with low electricity access (45%) and an inefficient power transmission network. The government aims to achieve universal access and become an electricity exporter in the region by 2025. This study provides an invalu...

Calculating Repeating Thermal Bridges (RTBs) for Timber Frame (TF) closed panels that could occur in Offsite Manufactured (OSM) Modern Methods of Construction (MMC), such as exterior walls for nearly-to-zero operational energy dwellings to be constru...

The process of reactant transportation greatly affects the performance of solid oxide fuel cells (SOFCs). Therefore, a three-dimension numerical SOFC model was built to evaluate mainly the effect of the reactant transportation coupling of heat and ma...

Hourly global solar irradiance (GSR) data are required for sizing, planning, and modeling of solar photovoltaic farms. However, operating and controlling such farms exposed to varying environmental conditions, such as fast passing clouds, necessitate...

Power quality and neutral section are two technical problems that hinder the development of electrified railway to high-speed and heavy railway. The co-phase power supply technology is one of the best ways to solve these two technical problems. At pr...

In this study, we evaluate the usefulness of mature landfill leachate (MLL) as a carrier allowing hydrodynamic cavitation (HD) of brewery spent grain (BSG). The HD experiments were conducted using an orifice plate with a conical concentric hole of 3/...

The article presents an analysis of the maximum efficiency and maximum load power, which are available to obtain in periodic wireless power transfer (WPT) systems. The numerical computations of the proposed WPT structures are performed using the fini...

Furfural is only derived from lignocellulosic biomass and is an important chemical used in the plastics, agrochemical, and pharmaceutical industries. The existing industrial furfural production process, involving reaction and purification steps, suff...

Nitrogen dioxide (N₂O) is a greenhouse gas that is harmful to the ozone layer and contributes to global warming. Many other nitrogen oxide emissions are controlled using the selective non-catalytic reaction (SNCR) process, but N₂O reduction methods a...

In this study, oil production and retention were observed and compared in 72 reservoir simulation cases, after which an economic analysis for various CO₂ and oil prices was performed. Reservoir simulation cases comprise different combinations of wate...

Aiming at the problems emerging in a pulse width modulation (PWM) drive system with long cables, the accurate modeling of power cables is the premise for predicting and analyzing these relevant phenomena, and a proper filter design is the key solutio...

Charge transporting materials (CTMs) in perovskite solar cells (PSCs) have played an important role in improving the stability by replacing the liquid electrolyte with solid state electron or hole conductors and enhancing the photovoltaic efficiency...

Ceramic outdoor insulators play an important role in electrical insulation and mechanical support because of good chemical and thermal stability, which have been widely used in power systems. However, the brittleness and surface discharge of ceramic...

For the first time in dye-sensitized solar cell (DSSC) technology, a di-carbazole-based dye was synthesized and evaluated for its usage as a potential sensitizer for the development of wavelength selective semi-transparent DSSCs for greenhouses-orien...

In this paper, the virtual synchronous generator (VSG) concept is utilized in the controller of the grid-connected dual two-level voltage source inverter (DTL VSI). First, the topology of the VSG and the DTL VSI are presented. Then, the state-space e...

The pulp and paper (P&P) sector is a dynamic manufacturing industry and plays an essential role in the Austrian economy. However, the sector, which consumes about 20 TWh of final energy, is responsible for 7% of Austria’s industrial CO₂ emissions...

Scroll compressors are widely adopted machines in both refrigeration systems and heat pumps. However, their efficiency is basically poor and constitutes the main bottleneck for improving the overall system performance. In fact, due to the complex mac...