This research aims to develop a conceptual framework for a design support model for energy-efficient vertical green façade systems with a focus on their thermal and shading performance. The model applies forecasting and backcasting methods based on an extensive literature review and analysis by the authors, with a particular focus on the energy efficiency parameters of vertical green façades. The key parameters are related to the location (climate, surroundings, orientation of the façade), system type (air gap dimensions, irrigation, structure, and substrate type) and plant characteristics (leaf area index, leaf absorptivity, foliage thickness, stomatal resistance, typical leaf dimensions, leaf emissivity, transmission coefficient, radiation attenuation) determined from actual data collected from buildings. This holistic approach changes the perception of a user and an architect while facilitating the design process. The method’s limitations result from the scarcity of comparative expe... [more]

At present, the trend of all sectors and industries, especially the oil and gas industry, is towards reducing carbon dioxide emissions. Along with the modernization of technological processes, special attention has been paid to the reduction in greenhouse gas emissions from vehicles that run on gasoline and diesel. An effective solution in this field is the transition from vehicles with combustion engines to electric vehicles, similar to the use of the electric bus in public transportation. How to charge these electric buses is a challenge for researchers. By proposing a flash charging method for electric buses, the feasibility of using these buses is obtained. Due to the pulsating nature of the power demand in this charging method, the prevention of negative effects on the network by this type of load should be considered. These negative effects can include power quality problems, voltage drop, frequency instability, and overload of transmission lines and transformers. This paper pres... [more]

In normal operation, there is no significant thermal stratification phenomenon in the tube bundle area of the steam generator of the nuclear power plant. However, this phenomenon is detected in marine nuclear power plant isolation loops in the presence of feedwater leakage. Therefore, an experiment was designed to verify the presence of thermal stratification, and the influence factors were analyzed by the RELAP5/MOD3.2 program. The results show that thermal stratification is mainly influenced by the initial water level at isolation, the initial pressure at isolation, the total leakage mass, and the internal circulation of the steam generator. Leakage flow has little effect on it. This phenomenon causes the coolant temperature at the primary side of the steam generator in the isolated loop to be lower than the temperature measured in the reactor inlet pipe or outlet pipe. This study aids the operator in determining the real coolant temperature at the primary side of the steam generator... [more]

Due to the simple structure and the possibility of manual production, coin cells enable fast and, compared to larger cell formats, an inexpensive examination option in battery research. The comparability and traceability of coin cell structures in literature are only feasible to a limited extent due to the lack of a standard in manual production. Since the findings from the literature are barely building up on each other and have not been repeated, a full factorial Design of Experiments (DoE) was performed to investigate the significance of earlier findings in terms of their influence on the reproducibility of the performance. The parameters studied were the anode-to-cathode ratio, the amount of electrolyte, the spring type and the separator count. To quantify the reproducibility of coin cell assembly, the number of functional cells (here: successful formation followed by 30 cycles) and the empirical coefficient of variation for the performance parameters discharge capacity, internal r... [more]

CO2 emissions associated with hydrogen production can be reduced replacing steam methane reforming with electrolysis using renewable electricity with a trade-off of increasing energy consumption, water consumption and cost. In this research, a linear programming optimization model of a hydrogen production system that considers simultaneously energy consumption, water consumption, CO2 emissions and cost on a cradle-to-gate basis was developed. The model was used to evaluate the impact of CO2 intensity on the optimum design of a hydrogen production system for Japan considering different stakeholders’ priorities. Hydrogen is produced using steam methane reforming and electrolysis. Electricity sources include grid, wind, solar photovoltaic, geothermal and hydro. Independent of the stakeholders’ priorities, steam methane reforming dominates hydrogen production for cradle-to-gate CO2 intensities larger than 9 kg CO2/kg H2, while electrolysis using renewable electricity dominates for lower cr... [more]

The purpose of this research is to develop effective methods for the thermal calculation of an electromagnetic mill. The article deals with the structural features of the liquid cooling system of such a device, with direct channel cooling of the induction coils. By analysing the recent research in this area, I have revealed that in order to achieve this goal it is expedient to use the finite element method (FEM). I have also suggested the input data for the boundary values to calculate a three-dimensional thermal field of an electromagnetic mill with an internal diameter of the working chamber of 200 mm. I have also graphically shown the results of calculating this problem using FEM analysis. Based on the analysis of the temperature field and gradient, I have also synthesized and substantiated the structure of the thermal equivalent circuit, which approximates the active part of the mill with a complex of five bodies with internal heat release and enables an approximate estimation of i... [more]

The limited availability of fossil fuels such as coal and increasing air pollution levels due to the burning of coal have pushed the trend of generating electricity from fossil fuels to generating it from locally available renewable resources. It is expected that the cost of electricity will decrease when locally available renewable resources are used. In this paper, it was proposed to commission a solar PV system in a part of an academic building of SRM IST University. The present study is an effort in-line with many initiatives taken up by the Indian Government. The performance index of solar PV system was analyzed. Supporting data were obtained from the NASA PDAV tool and then techno-economical analysis was carried out on HOMER. The average performance ratio and capacity factor of the solar PV system were obtained as 64.49% and 14.90%, respectively. For the optimal configuration, the net present cost and the levelized cost of electricity are $639,981 and $0.34 per kWh, respectively.... [more]

This study aims to evaluate the trade-off between using cheaper and contaminated energy versus cleaner and more expensive energy and ultimately assess their combined effect on social externalities. We estimate the impact of air pollution and income level—mechanisms of energy consumption—on violent crimes and mortality rates. We propose an integrated causal analysis to address an endogeneity concern caused by the energy selection process by employing a difference-in-differences method (DiD) for the mechanism approach using policy changes. We explore the energy variations in neighboring counties caused by the implementation of green act policies to measure violent crimes and mortality rates using air pollution and income as the mechanisms. The results reveal that reducing fossil fuel by one terawatt hour can save 23 lives. Further, lowering nonrenewable energy use reduces 53 rapes yearly by lowering the maximum temperature, whereas decreasing fossil fuel does not negatively impact produc... [more]

In this paper, a 5.8 GHz π-stub decoupling network is proposed to improve the performance of a receiving antenna array (RAA) in microwave wireless power transmission (MWPT) systems. A set of general design formulas was derived for determining the electric parameters of the required π-stubs. To validate the new technique, a π-stub decoupling network was combined with RAAs. The simulated and measured results show that the performance of the RAA is greatly improved by loading the π-stub decoupling network. In addition, a miniaturized MWPT system was built. System-level measurements indicate that the novel decoupling network enhances the receiving power of the RAA by up to 36.4%. An extended application also shows the scalability and effectiveness of the network, implying its huge potential in large-scale receiving arrays.

In this paper, a new method is proposed to suppress the vibration caused by the modulation effect of high-order electromagnetic forces in permanent magnet (PM) motors. Firstly, the modulation effect of the radial force was investigated, which indicated that the higher-order electromagnetic force could cause modulated vibrations through the modulation effect. Then, auxiliary slots on the magnet surface and their effect on vibration reduction were investigated. The optimal shape of the auxiliary slot was found to minimize the noise of motor vibration. Finally, the method was verified experimentally.

Pulsating heat pipe is a promising two-phase heat transfer device that has many advantages such as a simple wickless structure and high thermal performance. Its thermal behavior is inherently time-dependent, and it can also be characterized by substantial spatial variations. However, there are few studies investigating the interaction or similarity of the local physical quantities, such as heat fluxes exchanged between the working fluid and the device wall in adjacent branches. In the present work, a new approach based on the application of cross-correlation analysis to local heat fluxes is proposed to deepen the understanding of the flow characteristics in pulsating heat pipes. The temperature distribution in the condenser of a seven-turn pulsating heat pipe was measured with an infrared camera, changing the power input. The local heat flux distributions were estimated by solving the inverse heat conduction problem in the tube wall. The cross-correlation of the heat fluxes at differen... [more]

Jordan was late in adopting seawater and brackish water desalination as a source until the late 1990s and early 2000s. However, ongoing studies are still discussing the technical, economic, and socio-political aspects of brackish water reverse osmosis (BWRO) desalination plants. In this study, the water−energy nexus was considered, in order to highlight the main challenges facing BWRO desalination. We discuss the use of photovoltaic (PV) technology, together with BWRO desalination, as an approach to compensate for ecological, financial, and social challenges in Jordan. For this purpose, the performance of nine existing BWRO desalination plants in the agricultural, domestic, and industrial sectors is assessed. The water performance is assessed based on water consumption, safe yield extraction, plant recovery rate (R, %), and compliance to local and international water quality standards; the Specific Energy Consumption (SEC, kWh/m3) is taken as the main evaluation criterion to assess the... [more]

Low-voltage direct current (LVDC) systems have been increasingly studied as new efficient power systems. However, existing studies have primarily focused on power conversion designs, control, and operation, and research on ground configurations of LVDC systemsis insufficient. Consideration of the installation criteria of protective equipment and grounding systems is crucial because ground configurations in general households for end users are highly associated with the risk of human electrocution. Therefore, we investigate a mid-point grounding system using capacitors to ensure electrical safety in a mono-polar LVDC system that a general end user can directly experience in a household. MATLAB/Simulink is used to analyze the fault characteristics of the mid-point grounding system using capacitors by considering the effects of DC on the human body based on the International Electrical Code (IEC). Consequently, this paper suggests the minimum required values of the capacitors and resistor... [more]

Islands are a constrained environment due to their geographical peculiarities and their land use accounting for, especially in the touristic locations, strong variability during the year. Consequently, the variation of energy demand to be met by variable renewable energy leads to a complex issue. This study aims at investigating the PRISMI Plus approach applied to the Island of Procida to drive the transition towards low-carbon and high-renewable energy system. The toolkit involves the analysis of local renewable energy potential, their potential matching of the energy demand, and the prioritization of the technological solutions to achieve the decarbonization targets set by the energy planning strategies. Three scenarios are designed for 2030 considering low, middle, and high penetration of renewable energy in the systems, results indicate that the amount of power production in low, middle, and high penetration of renewable energy scenarios are 0.18, 14.5, 34.57 GWh/year, respectively... [more]

Integrated energy−water systems have been explored using different process integration techniques considering the energy−water−carbon nexus to minimize the carbon footprint, e.g., pinch analysis techniques (power cascade table, water cascade table, and energy planning pinch diagram). However, the power and water losses while considering the energy−water−carbon nexus have not been explored in detail in the previous works. This work focuses on the modifications of the existing pinch analysis methods for energy−water−carbon nexus study while considering power and water losses, for an optimized energy−water system. Power and water losses should not be neglected in the analysis as they have a significant impact on the carbon emissions and overall capacities of energy and water. The effect of losses on energy storage capacity, outsourced electricity, water supply volume and water storage capacity were evaluated on an industrial case study. Results from the case study demonstrate that, while... [more]

A simplified model that calculates the deflagration pressure−time curves of a hydrogen explosion was proposed. The deflagration parameters (pressure peak, duration, deflagration index, and impulse) of hydrogen−air mixtures with different hydrogen concentrations were experimentally investigated. The results show that the pressure curves calculated by the model are consistent with experimental data pertaining to a methane and hydrogen explosion. By comparison, the pressure peak and deflagration index are found to be influenced by the aspect ratio and surface area of vessels. The impulse and explosion times at fuel-lean hydrogen concentrations are greater than those at fuel-rich concentrations. When the hydrogen concentration is between 34 vol.% and 18 vol.%, the greatest explosion damage effect is formed by both the overpressure and the impulse, which should be considered for hydrogen explosion safety design in industrial production.

The paper proposes a solution to the problem of estimating the uncertainty of the output power with respect to the design parameters for an electromagnetic vibration energy harvesting converter. Due to costly utilisation of time-domain mathematical models involved in the procedure of determination of the average output power of the system, an algorithm for developing the surrogate model that enables rapid estimation of this quantity within the prescribed frequency band limits is proposed. As a result, the metamodel sensitive to the most impactful design parameters is developed using Kriging with successive refinement of the design grid for gaining the accuracy. Under operational conditions with a constant magnitude of the acceleration signal and the prescribed frequency band limits, the surrogate model enables evaluation of the average output power of the system at 105 design points in less than 2 s of computer execution time. The consistency and accuracy of the results obtained from t... [more]

The share of industry in final global energy consumption was more than 30% in 2020, of which, the hard-to-abate sectors accounted for almost 60% of total final consumption in industry. Similarly, in Europe, industry accounts for around 25% of final energy consumption. In order to reduce the impact of industry in energy consumption and greenhouse gas emissions, Europe has set many policies that support and regulate the sector, including pricing carbon emissions in a cap-and-trade scheme called the European Emission Trading Scheme (EU ETS). According to the EU ETS, in 2021 the verified emissions of all stationary installations were around 1.3 billion tons of carbon dioxide equivalent emissions. In 2021, the total allocated allowances amounted to around 1 billion tons of carbon dioxide equivalent emissions, half of which were freely allocated. After reviewing the existing modeling approaches for industrial clusters and the available datasets, and assessing the energy consumption and carbo... [more]

This paper proposes a fully analytical loss model to reduce circling currents and improve the power efficiency of a class Φ2 inverter. Firstly, analytical expression of the switching node voltage is derived by analyzing its harmonic components. Based on the result, the power switch is modeled as a voltage source, where the circuit is simplified to a linear network and analytical expressions of branch currents are solved. Secondly, root mean square (RMS) values of branch currents and component losses are calculated to form the analytical loss model for a Φ2 inverter. The influence of circuit parameters on the circling current and power efficiency are thoroughly analyzed, which derives optimal design constraints to reduce circling currents of a class Φ2 inverter. Furthermore, detailed design guidance and equations are provided to calculate circuit parameters of a class Φ2 inverter, which reduces its circling currents and improves overall power efficiency. Finally, a class Φ2 inverter pro... [more]

Process heating represents about two-thirds of the energy that the industry sector consumes worldwide; this energy comes primarily from burning fossil fuels. There is a wide variety of processes for which solar technologies can supply energy. Within these technologies, the CSPth Central Tower produces heat at temperatures about 600 °C, making it suitable for high-temperature processes. A CSPth Central Tower can be combined with a fuel-based system to form a CSPth Hybrid Central Tower system, which results in a high-reliable energy source with low rates of CO2 emissions. In this work, the levelized cost of heat (LCOH) of the CSPth Hybrid Central Tower technology was calculated. SolarPILOT was used to design and evaluate the CSPth Central Tower; fuel consumption was calculated using a steady-state energy balance. The LCOH was evaluated considering the CO2 prices recommended by the High-Level Commission on Carbon Pricing. The analysis shows that this technology can be highly competitive a... [more]

The impact of single-slope solar still with and without flat-plate collector was evaluated experimentally and numerically. Experimental analysis was conducted for four different water depths (3, 6, 9, 12 cm) in on-sunshine hours between 11 AM to 5 PM in Bhopal (23.2599° N, 77.4126° E), India. The thermo efficiency was 51.31% for 3 cm water depth while 24.29% for 12 cm water depth in an active mode of operation. In the case of passive mode, the thermo efficiency was 17.02% for 3 cm water depth and 6.77% for 12 cm water depth. The average exergy efficiency of single-slope solar still is 66.60% for 3 cm depth which is higher than 12 cm depth, i.e., 23.14%. The hourly variation parameters of solar still were also calculated and analyzed. The overall results obtained in the analysis state that solar still performs effectively when coupled with a flat-plate solar collector. According to econometric evaluation, the fabrication expense of a single-slope solar-basin-still is 126.43$ whereas the... [more]

According to the requirements of weak current measurement in power grid, a weak current sensor with anti-low frequency interference ability is developed. The sensor adopts the principle of fluxgate detection and adds a magnetic ring on the original basis. The structure of the magnetic ring is simulated using comsol to further improve detection sensitivity. In order to solve the problem that the electromagnetic current sensor is vulnerable to the interference of geomagnetic field and power frequency magnetic field in weak current measurement, a magnetic shielding method with low cost is selected, and the shielding shell structure is designed using a finite element analysis method. The experimental results show that the minimum measurable current is 1 mA, the measurement range is 1 mA−1 A, and the bandwidth is DC-16 kHz. The designed magnetic shielding shell can effectively reduce 97.3% of the DC magnetic field interference and 95.7% of the power frequency magnetic field interference. Th... [more]

Morocco is a country with a lack of fossil fuel resources and an increasing demand for energy. This inspired the country to increase the use of renewable energy in the energy mix. The objective of this study was to conduct an optimization and techno-economic appraisal of a concentrated solar power plant (CSP) using different scenarios that took Ouarzazate city in the south of Morocco as a case study. To achieve this, several parameters were assessed, including the impacts of solar collector assemblies (SCAs), receiver types, heat transfer fluids, cooling systems, solar multiples, and thermal storage hours, with regard to the profitability of the CSP plant. Then, performance and sensitivity analyses were conducted to select the best integration scenarios based on different economic indicators, including levelized cost of electricity (LCOE) and net present value (NPV). The findings revealed that the use of the Luz LS-3 as the collector/SCA, Solel UVAC 3 as receiver, and Dowtherm Q as hea... [more]

Although the energy change field in the centrifugal pump has been investigated under quasi-steady conditions (QSC), equivalent information is not yet known during the rapid starting period (RSP). A centrifugal pump loop system is constructed to investigate the energy change field in the centrifugal pump during RSP. The RSP is selected as a linear rotational speed from 0 rev/min to 2900 rev/min (design rotational speed) and a constant valve opening of 0.569. Results show that the flow rate lags behind the pump head value with the linear increase in rotational speed. The large values of partial derivations of mechanical energy in normal and tangential components are mainly concentrated at the impeller outlet, whose position is insensitive to rotational speed. The region of dominant energy loss is negatively correlated with rotational speed, and an opposite phenomenon is observed in the region of dominant energy increase. With the rotational speed increasing, the mean energy gradient func... [more]

The application of microgrids (MG) is more and more extensive, therefore it is important to improve the system management method of microgrids. The intended costs can be further minimized when the energy management system is unified with demand side response (DSR) strategies. In this work, we propose a generic method of modeling the equipment in a microgrid including multiple stochastic loads. The microgrid model can be generated on a computer by converting the energy circuit diagram into a signal flow diagram. Then, a demand side response method based on binomial distribution is introduced, and loads are set to different probabilities according to importance. By applying the probability of loads and changing the return coefficient of loads, the problem of individual differences in demand side responses is solved, so as to improve consumer satisfaction. The proposed model is constructed as a mixed-integer linear program (MILP). Cases studies demonstrate feasibility of the proposed mode... [more]