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This research introduces an innovative analytical framework for studying the behavior of electric vehicles (EVs) in power grids. The approach primarily examines the dynamic State of Charge (SOC) and energy reserves of EV batteries. By thoroughly examining patterns of EV charging demand and operational states (charging, discharging, idling, and waiting) across various time intervals, including day and night periods, this study aims to provide a comprehensive understanding of EV dynamic behavior in power networks. The proposed model goes beyond traditional assessments by incorporating human behavioral patterns and responsiveness to economic signals, specifically investigating the impact of electricity pricing on user behavior. The core analysis centers on exploring the Vehicle-to-Grid (V2G) concept, viewing EVs not only as energy consumers but also as potential contributors to grid stability and efficiency. The study delves into how the interplay of dynamic EV behavioral characteristics and owner responses to pricing influences the overall energy consumption curve of the grid, thereby shaping the capability of EVs in providing grid support services. To quantitatively validate the effectiveness of the model, a detailed case study is conducted, offering empirical evidence of its practical utility. The research findings are quantified, highlighting the significant implications for decision-makers, grid managers, and stakeholders in the energy sector. The paper emphasizes the main outcomes, demonstrating how the proposed analytical framework can empower stakeholders in making informed decisions about policy and infrastructure development. The robust methodological approach presented in this paper serves as a valuable tool for evaluating the impacts of adopting V2G, providing strategic insights for a more sustainable and economically viable paradigm [ABSTRACT FROM AUTHOR]

This research study presents a novel approach to enhance the efficiency and performance of Battery Energy Storage Systems (BESSs) within microgrids, focusing particularly on the integration of wind energy. The inherent inconsistency and unpredictability of Renewable Energy Resources (RERs) necessitate the development of effective integration solutions to accommodate them. Our article provides a customized iteration of the metaheuristic algorithm referred to as the Contracted fitness-dependent optimizer. The proposed methodology involves the adaptive adjustment of migration rates based on habitat suitability indices, while also considering variations in perturbations. The incorporation of Lévy flight and an elimination phase significantly enhances the algorithm’s efficacy in problem-solving. In order to establish the superiority of our strategy over alternative optimization approaches, we conduct simulations across diverse conditions and subsequently compare the outcomes. It was calculated that the daily scheduling cost was 235.2$ and the daily operational cost was USD 268$. In Scenario 3, the total operating expenses and arranging costs for 1 day, respectively, were determined to be 165$ and 115$. Further, the highest depth of discharge level was around 77%. Moreover, a −9.18 kW and 23.02 kW maximum charging and discharging power adjustment was made. The findings of our study emphasize the economic and operational benefits associated with appropriately sized BESSs within microgrid contexts. These advantages have the potential to enhance battery longevity and promote the development of more sustainable energy systems. [ABSTRACT FROM AUTHOR]

A thermodynamic analysis was performed on a newly developed concentrated solar power (CSP) technology known as the Cross-Linear (CL), which addresses the issue of cosine loss in conventional CSP technology. The analytical model has been developed and validated using experimental data collected at the experimental site situated in Bhopal, India. The analysis was performed under direct normal irradiance of 775 W/m2 with the key objective to determine the optimum inlet condition of the heat transfer fluid (HTF) considering three optimization parameters: HTF outlet temperature, energy, and exergy efficiency of the receiver. Also, the exergy of the solar field is investigated depending on the available solar irradiation throughout the day for three different configurations of the heliostat field. After a comprehensive analysis of the results, the optimal air inlet temperature range was observed to be between 373 and 423 K, and the optimal air mass flow rate was overserved to be 0.0925 kg/s (333 kg/h), which provides energy and exergy efficiency values within 50% to 60% and 28% to 34%, respectively. The maximum electrical exergy efficiency for 30 kW plant capacity is observed to be around 70% at solar noon with a cosine factor of around 0.9 for 4-hour duration. [ABSTRACT FROM AUTHOR]

In this article, titania with silver nanoparticles is synthesized in composite form and suspended in water to prepare TiO2-Ag/water hybrid nanofluid. The thermal conductivity and dynamic viscosity of titania-silver/water for 0.1 vol.% and 0.2 vol.% are measured, and their regression models are used in simulation. Using ANSYS version 19, the CFD simulation of the flat plate solar collector model is conducted at different mass flow rates (0.01–0.025 kg/s) and at reduced temperatures (0–0.025 m2K/W). From the analysis, the performance of water and TiO2-Ag/water is compared for both energetic and exergetic aspects. The maximum enhancement of the heat transfer coefficient is about 13% and 16.1% for hybrid nanofluids of 0.1 vol.% and 0.2 vol.%, respectively, at 0.01 kg/s, compared with water. The maximum energy efficiency enhancement is around 0.85% and 1.03%, whereas the exergy efficiency enhancement is around 1.4% and 3.52% for 0.1 vol.% and 0.2 vol.% nanofluid, respectively, in comparison with water. [ABSTRACT FROM AUTHOR]

In order to study the feasibility of a liquid working medium working in a solid heat storage body, this paper experimentally studied a novel pilot-scale sensible thermal energy storage unit (STESU) with a channel-embedded solid thermal energy storage body (STESB). The material of the body with fluid channels is corundum castable, and the heat-conducting oil works as a heat-transfer medium. While working, the heat-conducting oil flows through the fluid channels of the solid thermal energy storage body, and the oil submerges the body for convection heat exchange in the unit. The charging experiments under different flow rates were carried out to evaluate the thermal performance of the heat storage unit, including temperature, power, and efficiency. The results indicate that the unit's thermal energy storage capacity is about 1.054 × 106 kJ. When the flow rate increases from 2.0 kg · s−1 to 2.8 kg · s−1, the heat storage power increases from 71.90 kW to 90.58 kW, the total heat transfer area and heat transfer coefficient increases from 3.29 to 3.60 W/K, and the working efficiency of the charge-discharge cycle is 95.6%, which indicates that the thermal performance of the unit is better than that of heat storage unit which uses air as the heat transfer working medium. [ABSTRACT FROM AUTHOR]

Thanks to top-notch vehicle testing and internationally standardized inspections, the modes of transportation are cleaner and more efficient today. Though the development for conventional internal combustion engine vehicles (ICEVs) has almost saturated today, yet it retains the commercial/heavy-duty (trucks and buses) automobile market. Thus, it becomes of utmost importance to analyze the well-to-wheel efficiency for determining the overall energy consumption and greenhouse gas (GHG) emissions while transitioning toward sustainable transportation. Electric vehicles (EVs) do have environmental impacts that are directly related to the country's electricity generation, as they may involve fossil burning where other alternative sources of energy are not adequately present. This paper presents the overall energy efficiencies and GHG emissions from commercial/heavy-duty ICEVs and EVs. The study also briefly compares the other vehicle segments like 2 Wheeler, 3 Wheeler, and cars. Finally, the results show that commercial/heavy-duty ICEVs are advantageous over heavy-duty EVs when the GHG emissions are considered as of today. The commercial/heavy-duty ICEVs emit over 405 g CO2e/km, and counter EVs produce 706 g CO2e/km. The GHG emissions from 2 Wheeler ICEV were 46 g CO2e/km and by the same segment, EV is 13 g CO2e/km. Moving toward the car segment, an ICEV car produces around 158 g CO2e/km and an EV of a similar model emits 67 g CO2e/km. Furthermore, the 3 Wheeler ICEV emits around 99 g CO2e/km and a 3 Wheeler EV produces lesser at 24 g CO2e/km. Moving further on well-to-wheel energy efficiency, ICEVs have a maximum overall energy efficiency of 28%. Since EVs use various sources of energy for charging the battery, the overall efficiency was found to be at least 21% and maximum up to 39%. Thus, on an average EVs presently have a well-to-wheel efficiency of 32% when electricity generation mix is used for charging. [ABSTRACT FROM AUTHOR]

Photovoltaic thermal-assisted solar infrared dryer and a battery-operated drying system for agricultural products were created in experimental research to lessen the demand for fossil fuels. The drying cabinet's sustainability index and energy efficiency were calculated in the experiments carried out at flow rates of 0.022 and 0.062 kg/s. As a result, the Improvement Potential (IP) index values for the two studies were calculated to be 2.42 and 1.19, respectively. These numbers are 2.38 and 4.06 for Sustainable Index (SI); 0.47 and 0.27 were derived for Waste Exergy Ratio (WER). In the two experiments, the average drying cabinet exergy was found to be 0.55 and 0.71, respectively. Likewise, it was found that the drying time is influenced by the flow rate; the drying times in the two experiments were 310 and 280 min, respectively. Additionally, it was determined that for the two experiments, the thermal efficiency of the photovoltaic thermal collector was 33.11% and 55.07%, its electrical efficiency was 11.65% and 12.38%, and its exergy efficiency was 0.85 and 1.15, respectively. The development and assembly of a brand-new, cost-effective photovoltaic/thermal collector that is based on air. Determining factors for the system include energy, exergy, and sustainable indicators. Energy saving 66.32%; Electrical efficiency increase 6.27%; Exergy efficiency increase 35.29% Drying cabinet exergy efficiencies increase %29.09. [ABSTRACT FROM AUTHOR]

In this study, Kemer eggplants (Solanum melongena L.) were examined in terms of system performance and energy efficiency after drying at constant air temperature and different operating systems developed on a heat pump dryer. The air velocity and the drying time have a negative correlation was observed. In addition, the Midilli & Kucuk model was the most appropriate model to explain the experimental data of dried eggplant samples obtained from this study. Effective moisture diffusivity was calculated between 6.08 × 10−10 and 7.30 × 10−10 m2/s depending on air velocity values. The reduction of the eggplant slices from 12.158 (g water/g dry matter (dm)) moisture value to 0.645 (g water/g dm) moisture value took 236 min at 1 m/s air velocity with the application of Serial Condenser and Parallel Evaporator Drying System (SCPEDS). The Serial Condenser Drying System (SCDS) was found to yield both the highest average condenser capacity with 2.256 kW and the highest system performance coefficient with 3.181. The brightness values (L) of dried eggplant samples increased compared to the fresh eggplant samples. The closest brightness value to the fresh samples was determined as 84.7 in the drying experiments with the air velocity of 0.5 m/s and the SCPEDS system. The other color parameters (b, C and h°) decreased during drying. The highest total color change value (8.05) was obtained with SCPEDS system at 1.0 m/s. The highest browning index value (63.48) was reached in the drying experiments performed with the SCDS system at 0.75 m/s. [ABSTRACT FROM AUTHOR]

Fossil fuel firing heating systems will be substantially abandoned in the near future due to the zero-carbon goals. They will be replaced with heating systems that use renewable energy sources. Since the investment costs and area requirements of the renewable energy systems are high, the developments of highly efficient electric fluid heating systems have critical importance for a sustainable, environmentally friendly and clean heating. Among the electrical heating systems, induction heaters offer quite easy to use and better adaptability to most heating systems by allowing fluid heating without the necessity for contact. In this paper, a comprehensive review of the evolution of the induction fluid heaters is given by presenting the historical background. The most important milestones of induction fluid heating systems are presented. The development strategies suggested by the different papers including patents are investigated. The findings revealed that induction fluid heating systems, which reach approximately 100% thermal efficiency. These systems are introduced as follows: clean, non-emitting fluid heating system. Because of this, the study concludes that induction fluid heaters are one of the most promising alternatives to other electric heating systems in the long run. [ABSTRACT FROM AUTHOR]

Energy efficiency is one of the key aspects in energy transition, especially in building construction. One of the important things is also thermal comfort of the individuals. In this article, the design and the first results for the novel sensor device used to measure skin temperature are presented at two points used for purposes of estimating thermal comfort, a subjective feeling expressing the satisfaction with the thermal environment. [ABSTRACT FROM AUTHOR]

Sustainable production is of the most serious concerns that affect production systems. In a manufacturing company, efficient energy consumption, which leads to significant environmental benefits, is an important factor that indicates the performance of sustainable production. This paper proposes a three-stage data-driven model to analyze energy consumption in production systems. The first stage develops energy consumption predictors, the second stage extracts production scenarios, and the last stage predicts the energy consumption for each scenario. We implemented the model in a steel manufacturing plant for investigating the electricity consumption (EC) of Electric Arc Furnace (EAF). First, we developed four groups of predictors where Boosted Neural Network achieved the best result in predicting EAF's electricity consumption (RMSE = 587, R-Squared = 0.859, MAPE = 0.073). Second, we extracted eight distinct production scenarios based on different amounts of input materials through a descriptive data-mining algorithm, K-means. Third, the EC of production scenarios was predicted by the best predictor. Feature analysis showed that Direct Reduced Iron(DRI), ladle age, and scrap grade-3 have the most effect on predicting EC. Scenario analysis illustrated that scenarios with a higher share of DRI cause a higher amount of EC. Contrastingly, input materials with more share of high-grade scrap types lead to more efficient EC. [ABSTRACT FROM AUTHOR]

Based on the super-SBM model, this paper studies the agricultural energy efficiency of five provinces in China from 2004 to 2015. In addition, the Malmquist index is used for dynamic analysis of agricultural energy efficiency and to identify drivers of these changes. The results show that: (1) The inland provinces have lower agricultural energy efficiency than the wealthy eastern coastal provinces; (2) Technological progress is the most important factor affecting efficiency changes, and the provinces with lower efficiency are more likely to achieve greater improvements; (3) The energy efficiency of the provinces that are agricultural intensive areas is relatively low. Therefore, adjusting the agricultural production structure and emphasizing diversified agriculture will help improve the energy efficiency of agriculture. At the same time, it is necessary to strengthen agricultural cooperation among different provinces to jointly improve agricultural energy efficiency. [ABSTRACT FROM AUTHOR]

This work proposes a novel cooling system of the inlet air for industrial applications in the hot climates using organic phase change material. This cooling system consists of an inductive fan, an underground heat exchanger including double pipe phase change material. A three-dimensional transient simulation was developed to predict cooling capacity (temperature drop) using the analytical solution method within the MATLAB open-source code software. A prototype of the system was designed, built and tested in laboratory conditions to validate the modeling results. The experimental setup shows an average temperature reduction of 6°C in the air-cooling system in nine working hours, which matches with the simulation results with a variance of less than 2%. Further simulations demonstrated that an industrial scale could reduce the average temperature of intake air to 10°C in 7 hours working. The offline analysis proved a significant energy conservation opportunity in power plants. This study showed that energy performance and power generation of an industrial-scale gas turbine can be improved by 1% and 1.2 MW, respectively. [ABSTRACT FROM AUTHOR]

The present study attempts to obviate the drawbacks of the stirred slurry catalytic reactor by using the wall of a square stirred tank reactor as catalyst support where a diffusion-controlled reaction occurs. The electrochemical technique was used to measure the rate of mass and heat transfer (by analogy) at the reactor wall which was fitted with closely-spaced semicylindrical turbulence promoters. The effect of various geometrical and hydrodynamic parameters on the mass transfer coefficient was quantified by dimensionless correlations. The promoters increased the wall mass transfer coefficients up to 80% and the volumetric mass transfer coefficients by an amount varying from 57 to 190% depending on the working conditions. Power consumption measurements reported that the turbulence promoters enhanced the reactormechanical energy utilization up to 303% depending on the working conditions. The additional roles of turbulence promoters in increasing the reaction surface area and cooling the reactor where exothermic diffusion-limited reactions may occur were indicated. Merits of the present reactor over the stirred slurry biochemical reactor such as protecting the catalyst against shear and thermal degradation were highlighted. [ABSTRACT FROM AUTHOR]

Gas turbines form a crucial component of energy-generating systems, and their failure leads to the failure of the entire energy supply to a system. There are many aspects in the Occupational Health and Safety (OHS) framework that have to be implemented scientifically to bring risks to a more acceptable level. In order to achieve this objective, a fuzzy Multi-Criteria Decision-Making (MCDM), which integrates OHS and risk assessment aspects was applied in a gas turbine manufacturing plant in India. A total of 27 hazards were identified at workplace dominated by Mechanical (44.4%) and Chemical Hazards (40.74%) followed by Electrical and Ergonomic hazards (7.4%). The likelihood and severity parameters in the traditional Decision-Matrix Risk Assessment (DMRA) were identified, and weights were attached to them using the Fuzzy Analytical Hierarchical Process (FAHP). To prioritize the hazards, the Fuzzy VIKOR methodology based on the output of FAHP (Severity-0.69; Likelihood-0.31) was utilized. In the workplace, prolonged exposure to metal polish fumes, dust from pneumatic grinding and hitting against moving parts were identified as three most hazardous activities. Even though the weightage of likelihood and severity were varied in range of 27–52% in the sensitivity analysis, the ranking order of top three hazards remained the same. The proposed fuzzy DMRA simulation model is advantageous over the classic DMRA approach, which does not assign weightage to the risk parameters and allows distinct prioritization of hazards at workplaces. [ABSTRACT FROM AUTHOR]

Developing countries are becoming the factory of the world where sustainable production is still far from developed countries. However, the acceleration of the 4.0 revolution with a close connection with the Internet of Things (IoT) achievements has forced developing countries to integrate with the trend of a circular and sustainable economy. In this paper, the emerging digital technologies of Industry 4.0 which concentration on the contribution of IoT, Virtual Reality, Augmented Reality, and Big Data in remanufacturing are reviewed. Based on IoT, remanufacturing, circular economy, and smart manufacturing, this paper has made the assessment and discussed the challenges and barriers of the 4th industrial revolution to remanufacturing, as well as the amazing opportunities that IoT technologies can contribute to the growth of the remanufacturing industry in developing countries. A value-creation perspective consists of the product which is remanufactured, the equipment and processes of remanufacturing which are adopted and associated with troubles of organization, are used to identify trends and gaps. Suggestions from findings show that it is necessary to detect the combination between cyber-physical systems and the IoT architecture to assistant smart remanufacture, parallel with developing data and infrastructures of communication and circular economy management models. It is clear that, in order to successfully develop the remanufacturing industry, emerging economies need to fully utilize the achievements of IoT technology through economic development strategies and policies in line with Industry 4.0 to create breakthroughs in sustainable circular economy development. [ABSTRACT FROM AUTHOR]

The European policy as well as the national legislation framework set targets toward energy reduction and decarbonization in all sectors. Considering the building sector a number of regulations have been defined in order to ensure the energy as well as the environmental upgrade of the building stock. The paper’s main target is to evaluate from the environmental perspective the green roofs technology in Southern Europe. Therefore, a Life Cycle Assessment has been performed following the international standards of ISO 14040 series, supported by SimaPro Software. The aim is to define the proposed green roof system, analyze its environmental impact and evaluate the air pollutants levels related to the life cycle of its construction materials. A comprehensive review of similar roof applications is presented and results are compared with the ones regarding conventional roof typologies. The economic feasibility of the proposed roof types is assessed and evaluated based on a Life Cycle Cost Analysis. Thus, an integrated evaluation approach for the examined solutions is introduced, mainly focusing on Mediterranean climatic conditions. Moreover, a sensitivity analysis is conducted in order to define the impact of green roofs construction’s life span in terms of maintenance and renovation. As concerns the comparison of the suggested two roof types, and based on the sensitivity analysis the Traditional Horizontal Roof is proved to cause less environmental impact comparing to the Extensive Green Roof mainly because of the components use. Finally, the use of different insulation materials is examined and evaluated from an environmental point of view for the suggested typologies that are most suitable for the Mediterranean climatic conditions. More specific based on the sensitivity analysis’ results, and as far as global warming category, in both green technologies, levels have dropped by approximately 61% (from 2,13 to 1,52 kgCO2 and from 3,08 to 2,46 kgCO2, respectively) when recycled extruded polysterene is used in the construction stages for insulation. [ABSTRACT FROM AUTHOR]

In this study, energy efficiency applications and corresponding energy saving results were evaluated in a Turkish fabric dyeing factory. The relationship between energy consumption and the production were evaluated by regression analysis. They were detailed with energy intensity index (EII), cumulative sum values (CUSUM), specific energy consumption (SEC), and radar chart. The energy efficiency efforts should be initiated from heat and electrical energy, which are the main energy types extensively used in the textile industry. Average energy consumption value of the last four years (2015–2018), which is 7134 TOE is reduced 49% including waste heat, flash steam and cooling water recovery, and insulation in dyeing machines, in the factory due to the implementation of the energy saving actions. Accordingly, a reduction of 25% SEC value is possible. Moreover, production planning has a significant impact on the total energy consumption in terms of full load capacity operation of the dyeing machines, which may cause 23% energy saving that is of great importance. [ABSTRACT FROM AUTHOR]

In this study, a heat recovery exchanger was designed to provide indoor air quality (IAQ) and energy efficiency for intercity buses used in public transport. The heat recovery exchanger enabled the supply of fresh air into the bus cabin in an energy-efficient way to obtain a clean indoor environment. Two different simulations were conducted in the study. The first simulation was performed to determine the amount of required fresh air for the bus. The fresh airflow rate requirement was identified based on the carbon dioxide concentration inside the passenger bus. In the other simulation, the effect of the design parameters of a compact heat recovery exchanger with offset strip-fin on the effectiveness of the heat exchanger was investigated. The results showed that about 25% of the total ventilation should be supplied by fresh air in order to satisfy IAQ inside the bus cabin. They also showed that the effectiveness of the heat recovery exchanger increased with an increasing number of both plates and fins, larger plate dimensions, and decreasing fin offset length. Without impairing the IAQ, the maximum heat recovery was achieved with the highest effectiveness obtained for 20%–25% outside air ventilation. [ABSTRACT FROM AUTHOR]

The sparsely populated hilly areas are most prone to the power cuts and low voltage power supplies if the national grids fall any short of electricity demand. Therefore the present study evaluates the decadal efficiency of state-owned electric utility facilities from 2009 to 20019, situated in different geographic terrains, in Uttarakhand state of India. The productive efficiency of the Electricity Distribution Divisions (EDDs) of Uttarakhand state was evaluated in a nonparametric method of Data Envelopment Analysis (DEA). The obtained results indicate the performances of some EDDs are not up to the mark and suffer from low technical efficiency. The average Technical efficiencies are recorded as low as 0.5 in 2014–15; lowest for the EDDs located in hilly terrain with a value of 0.23 in 2014–15. An improvement trend in efficiency was noted with rearrangement of EDD during 2015–2017. Based on these findings, this study identifies potential for improvement. The recommendations and policies framed should keep geographical location into consideration. Region-specific policy interventions can help the state to achieve the efficient power goals by reducing electricity losses and improving overall efficiency. [ABSTRACT FROM AUTHOR]

The conventional refrigeration ejector cycle utilizes a constant temperature process during motive heat consumption needed for vapor generation. This may be thought of as the main restriction concerning the application of low-grade heat as a motive source by these systems since it results in required significant mass flow rate with a small temperature drop of heating fluid. The first proposed novel approach is an ejector flash cycle (EFC) in which the working fluid is heated up to the saturation temperature only at the inlet to the primary nozzle of the ejector. The second possible approach is the application of a zeotropic mixture as the working fluid for the conventional ejector cycle. The performance of an EFC is compared to the ejector refrigeration cycle (ERC) working with zeotropic refrigerant. Three motive heat source temperatures (60°C, 75°C, 90°C) and two evaporation temperatures (0°C, 6°C) were tested. Eight pure low-GWP refrigerants and four low-GWP refrigerant blends were analyzed. It was demonstrated that the flash cycle can efficiently operate with low-temperature motive heat source (60°C) with refrigerants R1234yf and R1234ze(E). The highest coefficient of performance (COP) is attainable for propane with a motive source temperature of 60°C and R1234ze(Z) for the motive temperature of 75°C and 90°C. The differences of liquid pump power consumption of both discussed cycles compared to the conventional compression cycle are significant and reach up to 90 percent in the case of EFC and up to 96 percent in the case of the zeotropic cycle. The electric power savings in the case of the zeotropic cycle are slightly higher, but COP and drop of the heating water temperature are notably lower. Therefore, the EFC system is suggested to be a better solution for low-grade heat utilization in the cases when a significant decrease of the motive source fluid temperature is required. [ABSTRACT FROM AUTHOR]

In this study, energy consumption is simulated for a residential complex in the cold weather condition of Iran. For this purpose, Tabriz is selected as the representative city. The mathematical equations are suggested to connect the consumed energy (such as electricity and gas consumption) with the required parameters including ceiling insulation, wall thickness, and the window height. The validation is applied to check the results via converting the data into neural networks and employing the genetic algorithm at each level of the study. The error between the software results and also the calculation of building gas consumption is about 9.6% in September and October while the error between the regression function and the measured values was less than 6%. The results show that, in the cold weather condition, the power density of equipments and the efficiency of heating system have the most effect on the electricity and gas consumptions, respectively. Also, in the regarding weather condition, window height has negligible effect on electricity and gas consumption. [ABSTRACT FROM AUTHOR]

The present current study aimed at analyzing the input–output energies and optimizing energy efficiency and greenhouse gases (GHG) in crops production at the northeast of Iran. The results of this research showed that the total energy inputs were equal to 42.4, 28.6, and 72.8 GJha−1 for, wheat, barley, and sugar beet, respectively. It was also shown that the highest energy efficiency, the lowest GHG emissions, and GHG intensity all belonged to barley production. The highest percentage of GHG intensity pertained to sugar beet production (41%), which was followed by wheat (38%) and barley (21%). It was also revealed that GHG intensity is a better criterion for the study of GHG since it also makes use of the energy output information in crops. The optimal model responses for the crop type and proper cultivation planning was 284432 hectares in terms of barley production, while those responses for wheat and sugar beet were zero and, thereby, they were eliminated from the model of Multiple Goal Programming (MGP). In the same way, this model could increase energy efficiency to 444875, while GHG emissions and its intensity decreased by 213259 tonCO2eq and 1.3 tonCO2eq MJoutput−1 per year, respectively. [ABSTRACT FROM AUTHOR]

In this study, to meet the electrical load requirement of Yalova University campus, grid-connected hybrid power generation simulations, and grid-independent hybrid power generation simulations were made with the Hybrid Optimization Multiple Energy Resources program. Eight alternative scenarios have been surveyed by employing annual solar radiation and wind speeds, fuel cost parameters, and energy storage need of the campus. Photovoltaic panel/wind turbine/diesel generator/battery/converter is proposed in hybrid energy system scenarios. In the analysis, net present value, cost of energy per unit, emission values, renewable energy rates and sensitivity analysis are calculated and presented in figures and tables. The energy production using renewable energy sources at 61.6%, 65.4% and 75.2% and the systems without renewables were investigated. As a result of the study, it was determined that the emission of the case whit 0% renewable energy is 7.3 times higher than the case with 75.2% renewable energy used. It was seen that the emissions of the scenario with 75.2% renewable energy used are 1.56 times less than the scenario with 61.6% renewable energy used. [ABSTRACT FROM AUTHOR]

The main source of building energy consumption in Iran is fossil fuels. The building sector, as a result, is responsible for a high share of CO2 emissions in this country. To address the issue, the government has recently adopted the “green management system” policy in order to alleviate the severe rate of CO2 emissions from the government buildings. As a commitment to the policy, the University of Tehran plans to transform into the first green university of Iran through green retrofitting in the coming years. As the first step to the retrofitting process, this paper measures the potential of energy-saving and CO2 emission reduction in the University of Tehran Science & Technology Park (UTSTP) offices with the use of Building Information Modeling (BIM). For this, Building No. 2 of UTSTP is modeled in the environment of DesignBuilder software to provide a calibrated computational model for energy and carbon audit. A detailed audit is then conducted using the calibrated model to identify the major areas of energy loss in the case study. Based on the audit results, several green strategies are then proposed to improve the weak performance of building in the identified areas. The strategies include triple glazing windows, aerogel envelope, phase change material (PCM) insulation, and Trombe wall. Findings suggest that the thermal loss from the building structure as a result of insufficient levels of insulation in the building components is the main source of energy loss in the building. Simulation results show that green strategies to a large extent have good energy-saving and mitigation potential. Full implementation of the proposed green strategies would reduce the annual heating needs and CO2 emissions of the case study by 51.6% and 5.39% respectively. [ABSTRACT FROM AUTHOR]

The study was conducted to evaluate the thermal performance of a box-type solar cooker (BTSC) by implementing two Fresnel lens magnifiers (FLMG) which concentrate the solar irradiance on to the cooker surface. A comparison in thermal performance was done in the presence and absence of the Fresnel lens magnifier. Three main tests, namely, stagnation test, load test, and cooking power test were conducted for determining the performance. It was seen that the first and second figure of merit increased from 0.11 to 0.12ᵒCm2/W and 0.43 to 0.45 respectively in the presence of the Fresnel lens magnifier. A linear regression analysis of the plotted points was used to develop a relationship between standardized cooking power and temperature difference and the cooking power for a temperature difference of 50ᵒC was calculated. The cooking power enhanced from 43.83 W to 46.87 W at the temperature difference of 50ᵒC by the usage of the magnifier. The average value of transmittance for the magnifier was 72.26% for the solar energy spectrum. The geometrical concentration ratio was increased by 48.7% by incorporating the Fresnel lens magnifier. The average value of energy efficiency of the solar cooker was calculated and was found to increase from 29.6% to 32.04% by adding the Fresnel lens magnifier. [ABSTRACT FROM AUTHOR]

In the present work, a sensible heat storage system with multi-tubular cavities is tested. Heat storage system having a capacity of 8 MJ is made of concrete and air is selected as heat transfer fluid. The diameter of the cylindrical heat storage system is 0.29 m which contains multiple tubular cavities each having diameter of 0.019 m. It is observed that the effect of mass flow rate on different parameters is found negligible beyond 0.029 kg/s. The maximum energy efficiency of the fully charged system corresponds to the maximum mass flow rate while fluid enters at minimum temperature. Sensible heat storage at fluid flow rates of 0.029 kg/s and 0.031 kg/s are in close approximation irrespective of the fluid temperature. [ABSTRACT FROM AUTHOR]

Lignite is the most important domestic energy source and dominated electricity production in Turkey for many years. Recently, new lignite coal reserves have been explored and are thought to contain 15.6 billion tons, which would constitute about 7.1% of the total world's lignite reserves. However, the potential capacity to be installed in these fields has not been effectively utilized yet. The total installed capacity reached 78,497 MW, and lignite-fired power plants had only 11.8% of this capacity in 2016. Furthermore, gross electricity production in Turkey was 274,407 GWh and the share of lignite was about 14% in the same year. It is expected in the near term, the role of domestic lignite will be increased in national electricity generation in Turkey. The electricity production of Turkey is outlined in this paper. The lignite reserves and lignite-fired power plants in Turkey are also introduced, and technologies used for producing electricity from lignite are mentioned. [ABSTRACT FROM AUTHOR]

Heat transfer has considerable applications in different industries such as designing of heat exchanger, nuclear reactor cooling, control system for spacecraft, and designing of microelectronics cooling. As the surfaces of two metals contact each other, this issue becomes so crucial. Thermal contact resistance (TCR) is one of the key physical parameters in heat transfer of mentioned surfaces. Measuring the experimental value of TCR in laboratory is highly expensive and difficult. As an alternative, numerical modeling methods could be engaged. In this study, inverse problem method solution is utilized as a proper method for estimation of TCR value. In this order, three different configurations (flat-flat, flat-cylinder, and cylinder-cylinder) were utilized in two steady and unsteady state conditions to predict the value of TCR. A comparison between the measured values and obtained values from the simulation show the errors for flat-flat, flat-cylinder, and cylinder-cylinder configuration after 10 min from starting the experiment are 4.6074%, 0.1662%, and 0.5622%, respectively. And in steady-state condition, the corresponding errors are 6.06e-3%, 1.506%, and 0.846%, respectively. In conclusion, the final results establish the fact that the inverse problem method solution can predict TCR values between contacting surfaces. [ABSTRACT FROM AUTHOR]

Energy is an important criterion in determining the world’s economy. Due to continuous industrial development, increase in population and standard of living leads to energy crisis and also increase in consumption of fossil fuels. The world is presently confronted with the dual crisis of fossil fuel depletion and environmental degradation. All countries are looking for a new energy source that will last for long period, and no environmental pollution. Biodiesel proves to be a good alternative to fossil fuels. But the viability of biofuel is also the key parameter for suggesting it as an alternate source for CI engines. The selection of optimum biodiesel with the appropriate blend for the IC engine plays a vital role in the energy sector. The objective of this study is to identify the apt fuel blend using hybrid Multi-Criteria Decision Making (MCDM) with various evaluating criteria and the alternatives.FAHP with TOPSIS and PROMETHEE are hybrid MCDM methods that are used to evaluate the suitable blend. FAHP is applied to find the relative weights of the criteria, while PROMETHEE and TOPSIS are used to identify the best alternatives. The performances of the MCDM methods were also analyzed with each other. A four-stroke single cylinder, constant speed, direct injection with a rated output of 4.4 kW was used for exploratory analysis. NOx, Smoke, HC, CO, CO2, BTE, EGT, ID, CD and MRP were considered as the assessment criteria. The priority ranking positions of the fuel blend alternatives are attained by FAHP with TOPSIS & PROMETHEE are B100

The approach proposed in this paper emphasizes the methodology of examining the possibility of increasing energy efficiency in the case of industry, such as a petrochemical complex, which is at the same time marked as the major pollutant of the environment. The improved cleaner production methodology was used based on the conditions and needs of the major Serbian petrochemical company. This paper presents results obtained by steam system optimization and modifications. The implemented measures lead to a decrease in total energy consumption by 6% and a decrease in greenhouse gas emissions by 9 t CO2e. [ABSTRACT FROM AUTHOR]

The effect of magnetic force on the hydrogen production by multielectrode water electrolysis is experimentally investigated in this paper. Results show that the hydrogen production rate, power increase rate and energy efficiency are improved as the magnetic field is added during the electrolysis process. At conditions of interelectrode distance of 3 mm, electrode pair of 5, electrolyte concentration of 25 wt% and applied voltage of 3 V, the hydrogen production reaches maximum amount of 5300 ml/h. At applied voltage of 2.5 V, energy efficiency can reach 92.14% as the magnetic field is added. The increase rate of hydrogen production is 13.4%, while increase rate of power efficiency is 10.2%, higher than that without magnetic field added. It indicated that the external magnetic field during water electrolysis indeed improves the electrolysis procedure. [ABSTRACT FROM PUBLISHER]

A low-cost parabolic dish collector was made and tested with commercial thermoelectric modules made of bismuth telluride for electricity generation on its focal plane; the energy end exergy efficiencies were experimentally evaluated. It was found that the daily average temperature of the receiver plate in the solar parabolic dish thermoelectric generator was 127.4°C with the maximum of 189°C. The energy and exergy efficiencies were in the range 0.94–1.68% and 1.01–1.81%, respectively. [ABSTRACT FROM PUBLISHER]

In the present article, the energy efficiency of the photogalvanic cell is studied by using crystal violet as a photosensitizer; ascorbic acid is used as an electron donor in the presence of surfactant diocyle sulphosuccinate. The photopotential and photocurrent generated by this cell were 754 mV and 195 μA, respectively. Power point and conversion efficiency of the cell is 0.40 and 0.69%, respectively. The effect of various parameters, such as pH; light intensity; diffusion length; temperature on cell photopotential and photocurrent; and variation of reductant, surfactant, and dye concentration, was also studied. The current voltage (i-V) characteristic of the cell has also been observed and a tentative mechanism for the generation of photocurrent has been proposed. Performance of the cell was determined in the dark at its power point and represented as t1/2. [ABSTRACT FROM PUBLISHER]

Eregli Iron and Steel Works Co. (Erdemir) is the largest integrated steel plant in Turkey. In this study, the potential for improving the specific energy use of slab furnace #3 of this plant was analyzed. An energy input and output model was established in order to determine the lost energy in the process. According to the study, energy efficiency of slab furnace #3 was calculated as 64.26%. Even though it seems to be a reasonable efficiency value for a slab furnace, it was noticed that further energy conservation can still be achieved by increasing the temperature of hot charging to the slab furnace and recovering the flue gas sensible heat remaining after the recuperator. [ABSTRACT FROM AUTHOR]

Hydrogen is a promising renewable fuel for transportation and domestic applications. Hence, in both the near term and long term, hydrogen demand is expected to increase significantly. Producing hydrogen, as well as any other synthetic fuel, will inevitably cost more energy than pumping up oil or using other fossil fuels. In this work, a review is made of the alternative technological methods that could be used to produce this fuel. Hydrogen can be generated in a number of ways, such as electrochemical processes, thermochemical processes, photochemical processes, photocatalytic processes, or photoelectrochemical processes. The thermal production process, which uses steam to produce hydrogen from natural gas or other light hydrocarbons, is most common. Steam reforming of natural gas is currently the least expensive method of producing hydrogen and is used for about half of the world's production of hydrogen. Approximately 95% of the hydrogen produced today comes from carbonaceous raw material, primarily fossil in origin. [ABSTRACT FROM AUTHOR]

Sustainability of renewable energy systems must support both human and ecosystem health over the long term, and goals on tolerable emissions should look well into the future. The sustainability of combustible renewables for energy use requires a high efficiency recycling of energy and low emissions of carbon compounds, NOx, persistent organics, and acidifying compounds and heavy metals due to biomass combustion. Electricity generation from combustible renewables has been found to be a promising method in the near future. The electricity is generated from combustible renewables, and advanced gasification and pyrolysis technologies are almost ready for commercial scale use. The electricity costs are in the 6-8 c/kWh range. Combustible renewables are utilized in different economic sectors in the OECD (Organization for Economic Co-operation and Development) countries. The combustible renewables are mainly used in the residential sector in non-OECD countries. [ABSTRACT FROM AUTHOR]

Achieving sustainable solutions to today's energy and environmental problems requires long-term planning and actions. Energy issues are particularly prevalent at present and renewable energy resources appear to provide one component of an effective sustainable solution. An understanding of the thermodynamic aspects of sustainable development can help in taking sustainable actions regarding energy. In this article, possible future energy-utilization patterns and related environmental impacts, potential solutions to current environmental problems, energy efficiency, renewable energy technologies and their relations to sustainable development, and how the principles of thermodynamics via exergy can be beneficially used to evaluate energy systems and technologies as well as environmental impacts are discussed. Throughout the article, current and future perspectives regarding thermodynamics and sustainable development are also considered. The results will likely be useful to scientists and engineers as well as decision and policy makers. [ABSTRACT FROM AUTHOR]

The method of energy use effectiveness of oil production and pipe-line transport systems by the efficiency test is suggested. The concept of idealized analogs of the processes for calculation of the minimum necessary energy/work consumption on their realization is used. The idealized analogs, under the assumptions made for their forming, are described. Determining the theoretic energy consumption is based on methods of hydraulic and thermodynamic analysis. [ABSTRACT FROM AUTHOR]

This article reports the effect of ash content in raw coal on the energy performance of coal fired thermal power plants of capacity range 30–500 MW. The focus is on primary energy effects—combustion, heat transfer, and flow hydrodynamics. The effects of variation of ash in coal from 6% (taken as standard) up to 75% on component performance are studied and overall unit performance is quantified based on experimental data. When the ash content increases from 6% to 75%, the effects on the system (without fuel oil support) are as follows: (a) total boiler area requirement (excluding air preheater [APH]) increases by 69%, (b) efficiency of boiler fans drop by 22%–27%, (c) drum mills show an increase in SEC of 115% while ball-race mills and bowl mills show an increase in SEC of 30%, (d) induced draft (ID), forced draft (FD), and primary air (PA) fans show an increase in specific energy consumption (SEC) of around 30%, 6%–14%, and 2%–7% respectively, (e) the gross and net overall efficiencies are reduced to 77% and 66% of their original values, (f) the ratio of the specific fuel consumption at a given ash content to that at standard ash of 6% increases from 1 to 10, and (g) specific fuel consumption (SFC) gross increases from 0.35 to 3.0. When the ash content of coal goes beyond 57%, limitations in combustion space and flow arise, and beyond this the unit has to be operated only at partial load. When the ash in coal exceeds 75%, its UHV is reduced to zero. [ABSTRACT FROM AUTHOR]