Energy Efficiency Research Articles

Analysis of the Potential Carbon Emission Reduction Through Interaction Between New Energy Vehicles and Smart Grids

Abstract: This paper analyzes the potential for carbon emission reduction through the interaction between new energy vehicles and smart grids, discussing how the optimization of energy efficiency and balancing of grid loads can be achieved through Vehicle-to-Grid (V2G) technology. The interaction between new energy vehicles and smart grids can enhance energy utilization efficiency, optimize grid management, and reduce reliance on fossil fuels by leveraging renewable energy sources, thereby achieving the goal of carbon emission reduction. However, this process faces multiple challenges including technological integration, cost-effectiveness, policy support, and societal acceptance. The paper proposes a series of strategic recommendations, including promoting technological standardization, enhancing policy and economic incentives, and increasing public awareness and participation, to support the effective interaction between new energy vehicles and smart grids, and to achieve long-term carbon emission reduction goals.

Contrastive signal-dependent plasticity: Self-supervised learning in spiking neural circuits.

Brain-inspired machine intelligence research seeks to develop computational models that emulate the information processing and adaptability that distinguishes biological systems of neurons. This has led to the development of spiking neural networks, a class of models that promisingly addresses the biological implausibility and the lack of energy efficiency inherent to modern-day deep neural networks. In this work, we address the challenge of designing neurobiologically motivated schemes for adjusting the synapses of spiking networks and propose contrastive signal-dependent plasticity, a process which generalizes ideas behind self-supervised learning to facilitate local adaptation in architectures of event-based neuronal layers that operate in parallel. Our experimental simulations demonstrate a consistent advantage over other biologically plausible approaches when training recurrent spiking networks, crucially side-stepping the need for extra structure such as feedback synapses.

The Relationship Between Production Efficiency and Factor Allocation Efficiency: A Case Study Based on Thermal Power in China

This paper introduces a novel decomposition method for analyzing production efficiency based on the Data Envelopment Analysis framework, addressing the limitations of traditional approaches that often fail to isolate the contributions of individual factors. The proposed method disaggregates production efficiency into capacity utilization, labor utilization efficiency, energy utilization efficiency, and technological change, providing a more granular view of how different factors contribute to overall efficiency. By incorporating both contemporaneous and intertemporal perspectives, this approach enables a comprehensive understanding of efficiency dynamics and factor interactions over time. To demonstrate the feasibility and robustness of the proposed method, we apply it to the thermal power industry using data from 30 Chinese provinces covering the period from 2011 to 2021. The empirical results validate the effectiveness of the decomposition framework, revealing distinct regional disparities in efficiency and providing insights for targeted resource optimization strategies. Based on these findings, we offer recommendations to enhance capacity utilization, improve energy efficiency, and support sustainable development within the thermal power sector. This research contributes a powerful analytical tool for disaggregating production efficiency and offers a theoretical foundation for future studies seeking to understand the nuanced relationships between comprehensive production efficiency and single-factor efficiencies, thereby supporting better policy and management decisions in complex production systems.

Entropy generation outcomes in peristalsis of Carreau–Yasuda nanofluid flow with activation energy

AbstractThis paper focuses on the study of activation energy and entropy generation in the peristaltic flow of a Carreau–Yasuda nanofluid. Peristaltic transport, coupled with entropy generation and activation energy in a curved geometry, has significant applications in biomedical and industrial processes involving non‐Newtonian fluids. Blood flow in the arteries, the movement of chyme in the gastrointestinal tract, and peristaltic motion replicate the natural muscular contractions that drive fluid flow in the physiological systems. The integration of entropy generation allows for the evaluation of energy efficiency and the analysis of losses due to viscous dissipation. Activation energy plays a crucial role in processes such as drug delivery, where temperature‐sensitive reactions or biochemical changes affect fluid behavior. In industrial applications, like peristaltic pumps in chemical reactors or polymer processing, the consideration of entropy and activation energy aids in optimizing thermal management and reaction rates. The mathematical model is developed under these assumptions, and the governing equations are numerically solved using the NDSolve function in Mathematica. Graphical results show that higher activation energy and concentration reduce the reaction rate, while the Bejan number and entropy generation increase with a larger Brinkman number. Velocity and temperature increase under slip conditions, whereas concentration decreases, and a stronger radial magnetic field reduces both velocity and the size of the trapped bolus.

Regulatory Mechanisms and Applications of Rare Earth Elements‐Based Electrocatalysts†

Comprehensive SummaryAmidst the pressing environmental challenges posed by the prevalent reliance on fossil fuels, it becomes imperative to seek sustainable alternatives and prioritize energy efficiency. Electrocatalysis, which is renowned for its high efficiency and environmental friendliness, has garnered significant attention. Rare earth elements (REEs), distinguished by their unique electronic and orbital structures, play a crucial role in electrocatalysis. The strategic integration of REEs into catalysts allows for the fine‐tuning of atomic structures, which in turn, significantly boosts catalytic performance. Despite substantial advancements in rare earth‐based materials for electrocatalysis, a comprehensive overview of the regulatory mechanisms involving REEs is lacking. In this mini‐review, we systematically explore the regulatory mechanisms of REEs within electrocatalysts and their pivotal roles in essential electrocatalytic processes such as the CO2 reduction reaction, oxygen reduction reaction, and hydrogen evolution reaction. We commence with an elucidation of REEs, proceed to delineate their regulatory impacts on electrocatalysts and delve into their applications in key electroreduction reactions. We conclude with discussions on current limitations and prospects for further advancements in this burgeoning field of research. Key Scientists

Exploring the Interaction and Impact of Green Building Design on People and Space

Abstract: With the progress and development of society, people's living standards improve at the same time, environmental pollution and resource shortages environmental problems also come. Construction engineering is one of the largest energy-consuming industries in China, and the implementation of a sustainable development strategy has become a top priority. Therefore, the state put forward the concept of greening and sustainable development, and green building has become a mainstream design concept. The purpose of this paper is to elaborate on the principles and design points of green building design and to study and discuss the application cases of green building design. Analyze the interaction and impact of green building design on people and space by analyzing the effects and impacts of the implementation of different designs in green building design cases, including focusing on siting design, ventilation design, energy efficiency design, recyclable design, plant design, and lighting design. Summarise the importance of applying green building design concepts and effective designs that have a positive impact on people. The results of the study can provide practical suggestions on improving the sustainability and eco-friendliness of green buildings for green building design stakeholders, such as architects, policymakers, and related stakeholders, and this study has certain reference values and significance.

Evolution of computing energy efficiency: Koomey's law revisited

For information and communication technology power consumption to be sustainable, the energy efficiency of computing systems must grow at least as fast as the demand for computing services. It is therefore crucial to understand how energy efficiency is evolving and how it will trend in the future, in order to take appropriate measures where possible. This article analyses the evolution of this parameter by analysing high-performance computers from 2008 to 2023, contrasting the results with those from Koomey's Law. It is concluded, after comparing the two that in the studied period and in the near future, energy efficiency continues to grow exponentially but at a slower rate than that established by Koomey's Law (maximum energy efficiency doubles every 2.29 years instead of every 1.57 years). Another interesting result is that energy efficiency grows at a slower rate (doubling every 2.29 years) than performance (doubling every 1.85 years).

Regional variations in energy efficiency: Modifying China's industrial approaches to meet sustainability goals

China has devoted much attention to the “carbon peaking” and “carbon neutrality” objectives, the related research focuses on renewable energy, carbon removal, electrification, and hydrogen technologies. Yet, energy efficiency, especially in resource-based and older industrial cities continue to be a research gap in this regard. This study fills this research gap by assessing the role of China's national Industrial Transformation and Upgrade Demonstration Zones (ITUDZ) in energy conservation from 2010 to 2021. In this paper, applying the time-varying Difference-in-Differences (DID) method, we confirm that ITUDZ effectively decreases the energy utilization of these cities. These tests are reliable based on the results obtained above. Mechanism assessments show that the ITUDZ does so through enhancing green innovation and adjusting industrial patterns and that marketization enhances the energy-saving impacts. Geographical heteroscedasticity tests also show that the effects are significant for multi-urban areas and eastern China but weaker for central-western and single-urban city areas. Therefore, this study serves to add to the existing knowledge regarding place-based industrial policies and their contribution towards the realization of China's sustainable development agenda.

Innovative passive techniques and PCM integration in building envelopes for enhanced energy efficiency in desert regions

Rising energy demands in buildings for heating, cooling and operating appliances underscore the importance of implementing energy-efficient solutions. Passive cooling techniques provide a sustainable alternative to conventional, energy-intensive cooling systems, promising reduced energy consumption in buildings. Using a dynamic heat transfer model validated with ANSYS Fluent, this study examined three configurations: integrating phase change materials at the brick's centerline with cavities filled with air, EPS insulation, and emissivity coating. Additionally, the benefits of combining all three passive methods were evaluated. Results indicated that among the evaluated PCMs, capric acid demonstrated superior performance. While each passive method studied offers distinct advantages in enhancing thermal performance and achieving energy efficiency, assessing their combined effects revealed significant insights. Specifically, integrating capric acid at the brick's centerline, while simultaneously configuring EPS insulation in the upper cavities and emissivity coating in the lower cavities, yielded superior performance. This configuration significantly reduced inner surface temperature by approximately 6.6 °C and minimized heat flux by about 58.4 % compared to traditional bricks. Achieving energy savings of 56.24 %, this configuration shows potential to enhance both thermal comfort and energy efficiency in building applications.

Investigating the impediments to carbon emission mitigation in prefabricated construction: a stakeholder perspective

ABSTRACT Prefabricated construction is a promising global technology for reducing carbon emissions (CEs) in the construction sector. This study aims to identify critical factors affecting the life cycle of prefabricated buildings, understand their interrelationships, and develop targeted carbon reduction measures. A mixed-methods approach is employed, incorporating bibliometric analysis to identify key factors and the Delphi method to refine these factors through iterative surveys with diverse stakeholders. A 24-member scoring panel and a 3-member review panel consisting of experienced corporate practitioners were selected for the study. The DEMATEL-ISM approach was utilized to analyze causal and hierarchical relationships, revealing both direct and indirect impacts on CEs. The findings indicate that factors such as energy efficiency and behavior change significantly affect CEs in prefabricated buildings. The study categorizes 15 key factors, including energy efficiency, environmental properties, behavioral change, and water and solid waste management. Furthermore, it underscores the importance of building design, energy-saving awareness and habits, and policies and regulations in reducing carbon emissions in prefabricated construction. These insights are valuable for advancing sustainable building research, analyzing stakeholder attitudes, and informing engineering project studies.

Simulation and Experiments on Optimization of Vortex-Induced Vibration Power Generation System Based on Side-by-Side Double Blunt Bodies

In order to improve the utilization efficiency of converting low-flow current energy into electric energy for Reynolds number 10,000 ≤ Re ≤ 40,000, this paper proposes a vortex-induced vibration power generation system based on a side-by-side double blunt body. In this system, the side-by-side double blunt body structure is used in the current energy capture part to enhance the collection of low-flow current energy; the permanent magnet linear motor is used in the electric energy conversion part to improve the efficiency of electric energy conversion; and a laboratory device is constructed for testing. The effects of the blunt body structure parameters and the center spacing ratio on the energy harvesting performance of the system are qualitatively explained by constructing a simulation model. Compared with the single blunt body energy capture structure, the side-by-side double blunt body structure increases the vibration amplitude by 1.04 times and the lift by 1.14 times at the center spacing S/D = 2.4. Meanwhile, energy harvesting can be realized at a lower flow velocity, increasing the vortex-induced vibration’s energy capture range. Finally, the power generation system was experimentally verified in the laboratory, and the results showed that the vibration amplitude of the double blunt body structure was increased by 1.12 times compared to the single blunt body. The maximum output power of the generator is 10.55 W when the water velocity is 0.7 m/s. The energy conversion efficiency of the power generation system can reach a maximum of 52.93%, which is 12.33% higher than that of a single blunt body structure, which proves that the system has a higher power conversion efficiency than that of a conventional single conversion system.

Development of agrivoltaic insect net house to enhance sustainable energy-food production: a techno-economic assessment

Agrivoltaics (AV) systems are the simultaneous land utilization for sustainable energy and food production. However, AV may not be suitable for some crops that require rigorous pest management. This study has applied an innovative approach, combining AV with an insect net house to cultivate capsicum. The 1.8 kW AV system has been installed at a 3-m elevation to facilitate unrestricted tractor manoeuvrability for various farming operations. The structure can withstand winds as high as 140.4 km/h. The system has a 3,612-kWh energy capacity and a 51.41 kg food production capacity. The system's energy and food conversion efficiency are 14.09% and 154.8%, respectively, compared to the traditional systems. Economic metrics like a 2.20 benefit-cost ratio and a 9.39-year payback period have been included in the findings. Further, the land equivalence ratio is 1.97, indicating a better system than traditional AV and agriculture approaches.

Regulating Molecular Interactions in Polybenzimidazole Membrane for Efficient Vanadium Redox Flow Battery.

The tightly bonded structure of polybenzimidazole (PBI) membrane is the origin of its poor proton conductivity, which severely hinders achieving a cost-effective membrane for vanadium redox flow battery (VRFB). It desires a strategy to relax the membrane structure to significantly improve the proton conductivity and maintain its structure stability. Therefore, this work proposes a novel strategy through regulating molecular interactions within PBI membrane to loosen up the structure of PBI membrane and dramatically enhance the proton conductivity. The interactions in PBI membrane are switched by DMSO/water and acid through sequentially treating membrane with these solutions. The efficient PBI membrane prepared using this strategy demonstrates an outstanding performance for VRFB, with the proton conductivity enhanced by 3850% (from 1.9 to 76.3 mS cm-1), and VRFB achieves a high energy efficiency of 80.5% under 200 mA cm-2. More importantly, this work shed lights on the structure-property relationship of PBI membrane, and the mechanism in enhancing proton conductivity is unraveled, which is of great significance for the development of VRFB membranes.

Development and performance evaluation of an indoor thermal environment control algorithm incorporating MET estimation model with object detection

As people increasingly spend time indoors, the significance of the indoor environment in influencing occupant quality of life is becoming more pronounced. Traditionally, indoor environment control primarily relied on fixed temperature settings, which failed to accommodate the diverse circumstances of occupants. This approach limited the creation of a comfortable indoor environment and the enhancement of energy efficiency. Consequently, there is growing interest in occupant-centric control (OCC), which integrates metabolic rate (MET) information, which is a critical factor in determining the thermal sensation of occupants. Previously, a method was developed to estimate MET by classifying occupant poses and detecting the objects they interact with from indoor images. This study aims to develop and experimentally validate an indoor thermal environment control algorithm (ITEC-algorithm) using the MET estimation model and assess its effectiveness and applicability in real building environments.The performance evaluation revealed that the ITEC-algorithm significantly enhanced the comfort ratios, achieving improvements of up to 59% compared to the fixed temperature control and 28% compared to the control methods that only used the pose classification model for MET estimation. The energy consumption varied depending on the activity and control method, with a reduction of up to 88% compared to fixed temperature control. These results indicate that thermal comfort can be enhanced while minimizing unnecessary energy consumption by incorporating the MET of the occupants. Consequently, it has been confirmed that the ITEC-algorithm effectively improves thermal comfort by managing the MET of various occupants.

Considering Carbon–Hydrogen Coupled Integrated Energy Systems: A Pathway to Sustainable Energy Transition in China Under Uncertainty

The low-carbon construction of integrated energy systems is a crucial path to achieving dual carbon goals, with the power-generation side having the greatest potential for emissions reduction and the most direct means of reduction, which is a current research focus. However, existing studies lack the precise modeling of carbon capture devices and the cascaded utilization of hydrogen energy. Therefore, this paper establishes a carbon capture power plant model based on a comprehensive, flexible operational mode and a coupled model of a two-stage P2G (Power-to-Gas) device, exploring the “energy time-shift” characteristics of the coupled system. IGDT (Information Gap Decision Theory) is used to discuss the impact of uncertainties on the power generation side system. The results show that by promoting the consumption of clean energy and utilizing the high energy efficiency of hydrogen while reducing reliance on fossil fuels, the proposed system not only meets current energy demands but also achieves a more efficient emission reduction, laying a solid foundation for a sustainable future. By considering the impact of uncertainties, the system ensures resilience and adaptability under fluctuating renewable energy supply conditions, making a significant contribution to the field of sustainable energy transition.

Integrated energy services in parks: Analyzing stakeholder dynamics and innovation under the REITs model through 23 policy documents

Industrial parks are significant consumers of energy, contributing to global carbon emissions and intensifying the need for strategic interventions to meet carbon reduction and energy efficiency goals. In China, the Real Estate Investment Trusts (REITs) model has been adopted to advance the development of Integrated Energy Services (IESs) within these parks. This paper analyzes 23 Chinese government policy documents to explore the key stakeholders in park-based IESs, particularly the central role of energy companies in shaping collective decision-making processes. The study highlights how business models, including financial investment, offline and digital services, and innovative practices, have evolved under the REITs framework to drive the development of IESs and foster collaboration among stakeholders.

Solar Species: Energy Optimization of Urban Form Through an Evolutionary Design Process

This paper proposes design guidelines to enhance energy efficiency and energy generation potential in active solar buildings. Additionally, it presents a variety of optimized urban forms characterized by attributes such as shape, layout, and number of buildings on the plot. These urban configurations are classified into solar species, each associated with a distinct range of high passive and active solar potential. These results were achieved by developing and applying a simulation-driven, multi-objective optimization technique for the early-stage design of a residential building cluster in a temperate climate. This method leverages both passive and active energy indicators, employing a genetic algorithm to identify optimal forms that maximize active solar potential while also minimizing operational energy demand. The approach utilizes a parametric modelling routine that relies on vertical cores and horizontal connections to produce design iterations featuring irregular geometry, while ensuring structural continuity and means of egress. The findings reveal a significant variability in onsite energy generation, with optimized solutions differing by a factor of 2.5 solely based on shape, underscoring the critical role of active solar potential. Taken together, these results hint at the descriptive and predictive capabilities of these solar species, making them a promising heuristic model for characterizing urban form in relation to energy performance.

Improving the Energy Efficiency of the Modular Buildings Drying Room: A Case Study of Construction Site Cabins

Improving the Energy Efficiency of the Modular Buildings Drying Room: A Case Study of Construction Site Cabins

Proposals on Effective Implementation of the Carbon Intensity Indication of Ships

The Carbon Intensity Indicator (CII) regulation is a short-term measure of IMO for reducing GHG emissions from ships. In addition, the 2023 IMO GHG Strategy describes that the CII regulation is anticipated to create a potential synergy effect with other measures. Accordingly, the CII regulation, which took effect in 2023, is forecast to increasingly impact international shipping and the commercial vessel market. However, efforts to improve energy efficiency and implement slow steaming for ships are insufficient to meet the CII regulation that is increasingly stringent over time. Therefore, there is a growing need for fundamental improvements in future response strategies. In this study, major causes of low CII ratings for ships were investigated from a recent consulting project that was conducted to support shipping companies in satisfying the regulation from operational and technical perspectives. Lastly, proposals to implement the CII regulation effectively and to reduce GHG emissions from ships fundamentally were made, taking into account the major causes derived from the consulting.

Enhancing shipboard waste heat management with advanced technologies

The complexity of the energy systems onboard ships, combined with the different operating/weather conditions and the availability of cutting-edge technologies, makes analyses for improving the energy and environmental performances of ships time consuming and challenging. From this point of view, this article provides new criteria for the sustainable design and management of energy systems of existing or new ships. In particular, the impact of the adoption of organic Rankine cycle units, wet steam volumetric expanders, and single or double effect absorption chillers is here investigated. Two types of ships are examined as suitable case studies, evaluating the impact of each technology and their combinations by varying the shipping cruises. By using a dynamic simulation approach, potential savings and optimal solutions are assessed for different energy system layouts by also comparing their economic, energy and environmental impact performance. Results are reported in specific performance matrices for helping stakeholders in preliminary energy efficiency analyses.In particular, outcomes show that high cooling demands of ships in the Caribbean Sea enable primary energy savings close to 4.5 %, compared to 3.5 % in the Mediterranean Sea and 3 % in the North Sea. In the latter case, cooling needs can be almost fully balanced through the examined energy recovery technologies. Screw expanders integrate best in all operating conditions with short paybacks, whilst organic Rankine cycles (with electrical efficiency above 8%) are advantageous especially in cold climate routes. Benefits on environmental impact are significant, with avoided CO2 emissions around 6 kt/y, depending on the selected ship cruise.