Energy-saving Advantages Research Articles

Architectural coatings and temperature Adaptive radiative cooling strategies applied in ten climate zones in China: Annual energy consumption Reductions and potentials

This research evaluates the energy-saving potential of high-reflectivity building materials, including three common coating types—normal (absorptivity 0.8, emissivity 0.8), cooling (absorptivity 0.2, emissivity 0.9), supercooling (absorptivity 0.05, emissivity 0.95), and Temperature-Adaptive Radiative Cooling (TARC) materials across 49 representative cities within ten climate zones in China using computational fluid dynamics simulations combined with the Demand.ninja energy consumption model. The results reveal that optimal solar absorptivity varies significantly between different climate zones, with higher absorptivity benefiting colder regions and lower absorptivity benefiting hotter regions. Urban microclimate simulations confirm that low solar absorption materials effectively reduce wall temperatures during the daytime and boost overall cooling energy savings, despite a slight increase in ambient air temperature. Building height-to-width ratios also influenced energy efficiency, with the best performance observed at a ratio of unity for both cooling and supercooling materials. Additionally, tests on the Temperature-Adaptive Radiative Cooling (TARC) materials demonstrate that TARCs offer significant energy-saving advantages, achieving an annual saving of 23.1 billion kWh across China by effectively balancing heating and cooling demands across different seasons. This superior performance is primarily attributed to TARCs’ ability to mitigate increased heating energy demands often associated with conventional cooling materials, especially in regions with substantial winter heating needs. Present research has highlighted the importance of climate-specific building material strategies and the potential of innovative materials like TARC for reducing energy consumptions, and this could favour the low carbon urban development.

Study of illumination and reflection performances on light-colored pavement materials

To accurately assess the light effects of light-colored pavement materials, a reflection measurement device was applied to evaluate the reflective characteristics of pavement materials equipped with light-colored aggregates and recycled glass. DIAlux evo software was employed for luminance-based lighting calculations to analyze the impact of reflection characteristics on lighting performance. The study highlights the necessity of using reflection characteristics to evaluate pavement lighting efficiency and confirms the energy-saving advantages of light-colored pavements. The results demonstrate that light-colored aggregates significantly increase the average luminance factor of asphalt pavements, converting the reflection type to diffuse reflection, while glass aggregates enhance specular reflection. Light-colored pavements effectively improve the luminous environment of road surface, ensuring both good visual performance and comfort, while reducing energy consumption per kilometer. From the perspective of light reflection mechanisms, diffuse reflective materials are most advantageous for energy-efficient lighting.

Energy efficient strategy for heterogeneous truck platooning based on a non-uniform platooning model

To investigate the energy-saving advantages of truck platoons, this study focused on two, three, and six-axle trucks as research subjects. A non-uniform platoon model of trucks was constructed based on braking performance differences. The aerodynamic characteristics of the non-uniform platoon fleet were analyzed in depth using numerical simulation methods, and the fuel consumption rate of the fleet was calculated. In a heterogeneous three-vehicle platoon, the 3-2-6 platooning approach exhibited the most effective reduction in fuel consumption, whereas the 3-6-2 platooning approach was the least effective. For a four-vehicle heterogeneous platoon comprising a three-axle truck, a six-axle truck, and two two-axle trucks, the 3-2-2-6 platooning approach yielded the best fuel efficiency. In a four-vehicle heterogeneous platoon with a two-axle truck, a six-axle truck, and two three-axle trucks, the 3-2-3-6 platooning approach proved to be the most effective in reducing fuel consumption. In a four-vehicle heterogeneous fleet composed of two-axle trucks, three-axle trucks, and two six-axle trucks, the 3-2-6-6 platooning approach achieved the best fuel efficiency. The conclusions of this study offer a fundamental scheme for truck formation, laying a crucial theoretical foundation for energy conservation and emissions reduction in transport systems.

Integrated battery thermal management and CO2 control in electric buses using recirculated air and waste heat recovery

In recent years, electric vehicles (EVs) have significantly progressed due to their environmental protection and energy-saving advantages. However, maintaining indoor thermal comfort and effective battery thermal management are critical considerations for EVs. Unlike conventional vehicles, EVs cannot use waste heat and depend on heat pump systems for winter heating and summer cooling. This research proposes a novel system to reduce the energy consumption of heat pump systems by using recirculated air while addressing the challenges of battery temperature management and maintaining safe CO2 concentrations in the cabin. The primary objectives of this research are threefold: first, to ensure passenger comfort through an integrated approach that includes cabin CO2 concentration safety; second, to recover heat from recirculated cabin air to save energy and control battery temperature; and third, to comprehensively analyze the performance of the Electric Vehicle Thermal Management System (EVTMS) using precise Computational Fluid Dynamics (CFD) analysis and mathematical modeling. This study will significantly enhance the understanding of energy consumption related to CO2 concentration control; an aspect previously overlooked in the literature. It will develop a battery temperature management strategy that leverages bus exhaust heat. These contributions will aid in achieving both passenger comfort and battery stability in electric buses, providing practical insights for the design and optimization of thermal management systems for future electric buses.

Optimum configuration of internal walls in intermittently conditioned rooms with different ventilation-behavior during off-periods and air conditioner operation durations

Investigations focus on optimizing insulation placement and thickness within internal walls of rooms equipped with intermittently operated air conditioners (AC), specifically targeting buildings located in China's Hot Summer and Cold Winter region. To achieve this objective, cooling and heating transmission loads for internal walls with varying insulation thicknesses, both internally and externally insulated, are calculated using EnergyPlus. Calculations are repeated across different air change rate (ACH) during AC off-periods and for varying AC operation durations. Subsequently, these transmission loads facilitate the determination of the optimal insulation position and thickness. The findings demonstrate that the internal walls with inside insulation (Wall-2) achieves an energy-saving rate of approximately 16–20 % during the cooling season and 30–60 % throughout the heating season when compared to that with outside insulation (Wall-1). Moreover, Wall-2's energy-saving advantage over Wall-1 is further accentuated with heightened ACH during off-periods and reduced durations of AC operation. Additionally, the optimal insulation thickness for Wall-2 was determined to be 0.06 m, 0.08 m, and 0.098 m for AC operation durations of 4 h, 7 h, and 10 h, respectively, with ACH having no impact on this optimal thickness. Life cycle savings varied between 254.56 and 552.31 ¥/m2/year, while payback periods varied between 1.76 and 2.33 years. These two indexes are both influenced by AC operation durations and ACH. Finally, the total energy consumption for cooling and heating is reduced by 40–50 %, when the internal wall is insulated to the optimal thickness internally.

Hydroxyl group modification improves the selectivity of metal single atom on poly(heptazine imide) for electrocatalytic acetylene semi-hydrogenation

Electrocatalytic semi-hydrogenation of acetylene to ethylene has recently attracted attention as a process for removing acetylene from ethylene-rich gas streams due to its mild conditions and energy-saving advantages. However, developing catalysts with low cost and high selectivity for acetylene semi-hydrogenation remains a huge challenge. Here, we investigated the effect of hydroxyl group modification on the acetylene semi-hydrogenation selectivity of poly(heptazine imide) (PHI) supported metal single atom catalyst under alkaline conditions by density functional theory calculations. The results show that hydroxyl group as ligand not only increases the steric resistance of acetylene adsorption, but also acts as electron-withdrawing group to delocalize the electrons of metal atoms, weaken the interaction with acetylene and subsequent intermediates, and make the adsorption moderate, which is beneficial to the desorption of ethylene and avoid over-hydrogenation. The Ni-OH/PHI and Fe-2OH/PHI are capable of achieving the selective hydrogenation of acetylene to ethylene and have good thermodynamic stability, which can be used as ideal catalysts for the electrocatalytic semi-hydrogenation of acetylene to selectively generate ethylene. This study provides theoretical guidance for the rational design of electrocatalysts for the selective semi-hydrogenation of acetylene.

Numerical Studies on the Hydrodynamic Patterns and Energy-Saving Advantages of Fish Swimming in Vortical Flows of an Upstream Cylinder

Numerical Studies on the Hydrodynamic Patterns and Energy-Saving Advantages of Fish Swimming in Vortical Flows of an Upstream Cylinder

Container technology for transporting rock masses in quarries

Container technology for transporting rock masses in quarries

Study on the synergistic effects and eco-friendly performance of red mud-based quaternary cementitious materials

Red mud, as the primary byproduct of processing bauxite into aluminum, raises environmental concerns due to its significant alkalinity and substantial heavy metal content. Addressing the limitations of traditional methods, this study proposes an innovative solution to utilize red mud, steel slag, fly ash, and phosphogypsum together to produce a new type of low-carbon, environmentally friendly cementitious material. Utilizing advanced techniques such as X-ray diffraction, thermogravimetric analysis, Fourier-transform infrared spectroscopy, mercury intrusion porosimetry, and scanning electron microscopy with energy-dispersive spectroscopy, this study conducted a comprehensive evaluation of cementitious materials, revealing their synergistic mechanisms. Furthermore, artificial neural networks and genetic algorithms were employed to optimize the mix ratio of the quaternary binder, aiming to predict and enhance the material's mechanical strength. Research shows that quaternary cementitious materials outperform traditional binary and ternary materials in compressive strength, hydration properties, microstructure, and environmental performance. Particularly, the increased content of calcium-aluminate-silicate-hydrate and sodium-calcium-silicate-aluminate-hydrate gels and a denser matrix structure highlight the synergistic effect in the hydration reaction of the quaternary system. Through mix proportion optimization, a significant enhancement in compressive strength up to 21.4 MPa is achieved. Environmental assessment shows that the composite material effectively solidifies Na+, with non-renewable resource and energy consumption reduced by 84.7% and 83.8%, respectively, compared to traditional cement, highlighting its environmental and energy-saving advantages. This approach addresses red mud storage, produces green building materials that meet standards, and fulfills resource and environmental goals.

Evaluation of energy-saving potential and indoor thermal environment of passive solar houses in various heating climate regions of China

ABSTRACT Passive solar houses comprise crucial strategies of reducing heating and cooling energy for buildings, which have been extensively used in plenty of nations. This study develops a study on indoor thermal environment, the energy-saving performance and natural lighting in different heating climate regions (represented by Lhasa, Xining and Urumqi). An attached-sunspace solar house integrated with phase change material floors is also proposed to ameliorate indoor thermal comfort and simultaneously diminish the heating energy consumption. In addition, the dominant factors analysis of building envelope affecting building energy consumption are sensitively studied. Moreover, the influence of the depth of sunspace and the intensities of internal heat gain on indoor thermal conditions and heating energy consumption are further analyzed. The results indicate that among the three types of solar houses, the passive solar sunspace offers the most stable indoor temperature and Trombe-wall solar houses and attached-sunspace solar houses have striking energy-saving advantages compared with the traditional houses. And the annual power consumption of 695.1 kWh, 427.4 kWh and 688.8 kWh in Lhasa, Xining and Urumqi can be saved in view of natural lighting respectively. Additionally, the whole natural temperature of attached-sunspace solar house is on the rise apparently when the PCM floors are embedded in the house and the energy saving fraction of these three regions is 81.9% for Lhasa, 68.8% for Xining, 55.7% for Urumqi respectively with the integration of phase change floors. The sensitivity analysis of key parameters impacting building energy consumption from high to low are the heat transfer coefficient of external wall, the ratio of window to wall, air tightness, the heat transfer coefficient of external window, and the heat transfer coefficient of roof. The depth of 1.2 m for sunspace is recommended as the optimal choice. Indoor natural temperature is on the rise as intensities of internal heat gain increase. The same downward trend for the main bedroom and the whole building is displayed with the increasing interior heat sources in terms of annual heating load.

Fan Mobility by Generated Electricity Harnessed from Dynamo

Fans are the most popular products despite the broad accessibility to air conditioners and coolers. There's a chance that using air conditioners more frequently to cool indoor areas will be a major contributor to greenhouse gas emissions worldwide. Using home fans to move indoor air can increase the temperature at which air conditionin g must be turned on to keep building occupants comfortable (Malik et al, 2022). Household fans are a great way of helping improve your home feel better because they reduce interior temperature, manage humidity, and offer energy-saving advantages. Programmers begin by using the Dynamo to create robotic outputs and other electronic and programming creations. Dynamo produces direct current electric power using electromagnetism. It is also known as a generator; however, the term generator usually refers to an alternator; which produces AC (alternating current). The rotating shaft rotates electromagnets surrounded by heavy copper coils wire inside generators. This creates a magnetic field which causes the electrons of the copper wire to move away from atom to atom that generates electricity. The voltage produced by a generator depends on the number of windings magnetic force and magnetic velocity turns. There are several steps involved in creating a fan with generated electricity harnessed from Dynamo. The first is to create a program that uses Dynamo to provide instructions that are programmed on the Dynamo board to facilitate user interaction.

Enhancing heat-exchanger performance in frost conditions via superhydrophobic surface modification

Frost accumulation significantly reduces the heat transfer efficiency of air source heat pump (ASHP) during winter operation, making frost suppression and defrosting critical issues that need to be addressed. This study presents a simple system optimization method that considers both active frost suppression and efficient low-temperature defrosting strategies to ensure prolonged efficient heat transfer. Heat exchangers with different surface properties (hydrophilic, hydrophobic, and superhydrophobic) were implemented, and the dynamics of frosting and defrosting processes were studied under high humidity conditions. The defrosting process employs low-temperature defrosting and quantitatively monitors heat transfer based on temperature differences, facilitating rapid defrosting in the event of a substantial decrease in heat transfer efficiency. Experimental results reveal distinct frost accumulation patterns between the fins, attributed to variations in freezing forms and surface properties of the droplets. The superhydrophobic heat exchanger ensures an effective heat exchange channel time of 25 min and 49 min longer than the hydrophobic heat exchanger and hydrophilic heat exchanger, respectively, showcasing excellent active frost suppression capability. After 90 min of frost accumulation, the defrost energy consumption of the superhydrophobic heat exchanger is 31.7% and 28.9% lower than that of the hydrophilic heat exchanger and hydrophobic heat exchanger, respectively. With the proposed defrosting strategy, the defrosting time of the superhydrophobic heat exchanger is reduced by 39% and 32.4%, and the heat gain is 11.7% and 11.3% higher than that of the hydrophobic and hydrophilic heat exchangers, respectively. Additionally, the superhydrophobic heat exchanger exhibits a 36.4% increase in heat gain compared to the conventional reverse cycle defrosting method. Additionally, in the cyclic frost-defrost study, the superhydrophobic heat exchanger maintained efficient heat transfer for 76.2% and 31.6% longer than the hydrophobic and hydrophilic heat exchangers, respectively. This prolonged efficiency is attributed to the effective drainage of water trapped on the fin surface. These findings underscore the potential of proposed defrosting strategies alongside dynamic studies of active surface frost suppression characteristics, offering significant energy-saving advantages.

Design and optimization of driving mode control strategies for front-and-rear-axle-independent-drive-type electric vehicle

In order to fully exploit the energy-saving advantages of front-and-rear-axle-independent-drive-type electric vehicle (FRID EV) configuration, this paper designs a drive mode control strategy for it. Based on the characteristics of the drive system with FRID EV, this paper categorizes the drive modes into three, and creates a mathematical model to determine the operating range. Then, an improved particle swarm optimization algorithm is used to optimize the torque distribution based on the principle of system efficiency optimality, so as to develop the optimal drive mode switching control strategy after torque optimization. Finally, the whole vehicle model is built in Cruise for joint simulation with MATLAB /Simulink. Results of the simulation indicate that the drive control strategy with improved particle swarm optimization can effectively improve the energy efficiency of the drive system and boost the vehicle economy, when compared to both the simple two-motor torque equalization strategy and the standard particle swarm optimization strategy.

Simultaneous reduction in laser welding energy consumption and strength improvement of aluminum alloy joint by addition of trace carbon nanotubes

The widespread use of laser welded aluminum alloys in industrial production offers potential benefits to sustainable development and socio-economic progress. It simultaneously enhances the weld strength while reduces the energy consumption. Despite the promise of these alloys, research on reducing their energy consumption during laser welding is lacking. In this study, a dual effect of enhancing joint strength in 2A12 aluminum alloy and reducing energy consumption is achieved by the addition of trace carbon nanotubes (CNTs). The “welding efficiency" is defined and an energy consumption model for laser welding of aluminum alloys is developed. Next, the laser welding process with the addition of trace CNTs (LC) and the single laser welding process (LW) were compared and analyzed. The results indicate that adding trace CNTs can reduce energy consumption by more than 33 % and increase joint strength by 101 MPa. Furthermore, it is found that the LC process offers significant energy-saving advantages over other laser welding of aluminum alloy processes described in previous studies. These improvements is attributed to the increased laser absorption by the aluminum alloy induced by trace CNTs, as well as their residual presence in the joint, which acts as a strengthening medium. This work provides new insights and presents a novel approach for achieving low-carbon, high-quality welding of aluminum alloys.

Enhancing the Grinding Efficiency of a Magnetite Second-Stage Mill through Ceramic Ball Optimization: From Laboratory to Industrial Applications

Ceramic ball milling has demonstrated remarkable energy-saving efficiency in industrial applications. However, there is a pressing need to enhance the grinding efficiency for coarse particles. This paper introduces a novel method of combining media primarily using ceramic balls supplemented with an appropriate proportion of steel balls. Three grinding media approaches, including the utilization of steel balls, ceramic balls, and a hybrid combination, were investigated. Through an analysis of the grinding kinetics and the R–R particle size characteristic formulas, the study compares the breakage rate and particle size distribution changes for the three setups. The results indicate that employing binary media effectively improves the grinding efficiency for +0.3 mm coarse particles while maintaining the energy-saving advantages of ceramic ball milling. Simultaneously, the uniformity of the ground product is ensured. This proposed approach has been successfully validated in industrial applications, providing robust theoretical support for the expansion of ceramic ball milling applications.

Smart window design offers a host of energy-saving advantages

Smart window design offers a host of energy-saving advantages

Improving the long-term performance of electric vehicles CO2 heat pump through correcting discharge pressure

Electric vehicle CO2 heat pumps are an environmentally friendly and energy-efficient solution, especially in cold regions, where they show exceptional heating capabilities and attract widespread attention. The optimal discharge pressure has consistently been the focus of research for enhancing energy efficiency in CO2 heat pump systems. The impact of declining heat transfer efficiency during the long-term operation on the optimal discharge pressure has yet to be thoroughly investigated. Establishing a simulation model for electric vehicles CO2 heat pump. Considering how performance degradation on both sides of the heat exchanger affects the optimal discharge pressure over the lifecycle. Proposing a mathematical correction method to adjust the initial discharge pressure and realize COP loss recovery from a control strategy perspective. The results demonstrate a gradual growth in the optimal discharge pressure, leading to a 15% additional COP loss after 10 years. The extent of heat transfer efficiency deterioration played a crucial role in determining the optimal discharge pressure deviation rate. Correcting the discharge pressure can minimize COP loss from a control strategy standpoint. Theoretically, under the specified test conditions, COP loss can be maximally recovered by approximately 2.48% (within 4 years) and 25.48% (within 10 years). This study contributes to the sustained reduction of electricity consumption in CO2 heat pump systems, thereby prolonging the energy-saving advantages of electric vehicles.

A comprehensive evaluation method of heat source tower heat pump applicability considering regional climate differences

The heat source tower heat pump system is widely used in large and medium-sized air conditioning systems due to its good energy-saving advantages. However, there is no relatively reasonable evaluation system for the applicability of heat source tower heat pumps due to significant regional climate differences. Therefore, in order to better comprehensively evaluate the applicability of the heat source tower heat pump system, a comprehensive evaluation index system for the applicability of the heat source tower heat pump system was first constructed. On the basis of this evaluation index, an applicability evaluation model based on backpropagation neural network is constructed. In response to the slow convergence speed and susceptibility to local values in the application process of this evaluation model, particle swarm optimization algorithm is used to improve it. A comprehensive evaluation model for the applicability of heat source tower heat pumps based on improved backpropagation neural networks has been constructed. For the evaluation model constructed in the study, experimental data from four different regions were selected for validation. The experimental results show that in the training set, the F-Measure value of the evaluation model reaches 0.949, and in the test set, the F-Measure value of the model reaches 0.973. The comprehensive evaluation data from four regions indicate that the heat source tower heat pump system can achieve different heating and cooling effects in different regions. This indicates that the proposed comprehensive evaluation model for the applicability of heat source tower heat pumps based on this improved method has good evaluation results. It can conduct a good analysis of the applicability of the heat source tower heat pump system, providing effective support for developing reasonable and energy-saving refrigeration and heating methods in different regions.

Intelligent and Fair IoV Charging Service Based on Blockchain With Cross-Area Consensus

The emergence of electric vehicles promotes the development of Internet of Vehicle (IoV). However, there are a series of security problems to be solved in the IoV. Firstly, how to allow vehicle users to find the nearest non-queuing charging pile without detours is a challenge. Secondly, applications in the IoV are delay-sensitive, while high communication delays caused by security mechanisms would bring serious consequences to vehicles. Thirdly, the verifiability and fairness between charging and payment are difficult to be guaranteed. Aiming at the efficiency and security problems of the charging service in the IoV, this paper proposes a blockchain-based intelligent and fair IoV charging service system. According to the multi-factor constraints between vehicles and charging piles, a multi-factor IoV branch and bound algorithm is proposed to intelligently recommend charging piles for vehicles and maximize the overall energy saving. We propose the cross-area consensus protocol to achieve low latency in vehicle communication. In addition, we ensure the fairness between charging and payment through a payment channel protocol based on verifiable encrypted signatures. Finally, we implement the proposed scheme, and we put the project prototype on an open source platform is available at: https://github.com/chenruonan/blockchain-based-intelligent-and-fair-IoV-charging-service-protocol. The experimental results demonstrate the low latency and energy-saving advantages of our proposal. When the payment is executed 250 times, the delay of our proposal is only 1.54% of the normal on-chain payment time.

Performance Analysis of a Designed Prototype of a Motor Coupled Variable Inertia Flywheel System

The presence of a substantial moment of inertia in a flywheel poses challenges at the initiation of rotation in a rotating machine. During stable operation at high velocities, several energy-saving advantages can be efficiently attained, allowing for the potential of achieving adequate energy savings in specific applications. One potential solution to address this issue is the implementation of a flywheel that possesses the ability to modify its moment of inertia. While it is possible to derive the concept of variable inertia by adjusting the radii of the masses in relation to the axis of the flywheel, the techniques employed to regulate the variable inertial flywheel are rather intricate. This study presents an implementation of a variable inertia flywheel system coupling with electrical machinery to reduce power consumption. The main objective of the study is to reduce energy consumption utilizing variable inertia flywheel. Under various motion scenarios, the advanced machine’s dynamic reaction is examined. Finally, a standard testing method demonstrates almost ninety seven percent similarity between an analytical and practical analysis.