Energy Efficiency Regulations Research Articles

Color Design for Daytime Radiative Cooling: Fundamentals and Approaches

The escalating global energy crisis and the worsening global warming have intensified the heat threats posed by high temperatures. Traditional cooling methods like air conditioning are not only energy-intensive but also contribute to environmental degradation. In response, there is a pressing demand for novel, eco-friendly cooling technologies, particularly amid the growing global push for carbon neutrality. As a passive cooling method that does not require any extra power input, radiative cooling offers a promising solution, utilizing thermal radiation to cool the Earth by transferring heat directly to outer space. However, current radiative cooling materials generally have a monotonous white appearance due to their high reflectivity to solar radiation, which, considering their prospects for outdoor applications, has prompted the need for color design. Recent advancements have led to the development of colored passive radiative cooling (CPRC) materials, offering passive cooling without additional energy input, colorful aesthetic appearance, and facile preparation methods. In this review, the latest progress in CPRC materials are summarized, covering fundamental principles, various color design solutions, and potential applications. Besides, the coloration strategy including chemical, structural, and luminescent approaches for CPRC are comprehensively analyzed, providing insights into the future development and deployment of CPRC materials for outdoor energy efficient systems and thermal regulation.

Thermal comfort benefits, energy efficiency, and occupant regulation behaviour in four types of personal heating within the built environment

The conventional approach to creating a uniform and stable thermal environment cannot guarantee the required thermal satisfaction rate and consumes significant energy. Personal comfort systems (PCS) offer a promising solution for office buildings. However, practical guidelines for selecting and operating PCS based on current studies remain elusive. In this study, 28 male participants were exposed to three cold conditions (16, 18, and 20 °C) and separately used four personal heating devices (PHDs): a warm air blower (WB), heated table mat (HM), heated cushion (HC), and leg warmer (LW). Variations in the subjective perception, skin temperature, heating setting adjustments, and operating parameters were monitored. The best improvements in overall thermal sensation under 16, 18, and 20 °C were achieved by HC (ΔOTSV = 0.97), WB (ΔOTSV = 0.85), and HM (ΔOTSV = 0.57), respectively. The energy consumption required to achieve the same thermal comfort benefit differed among the four PHDs. The corrective energy and power of WB, LW, HM, and HC were 64.0 W/K, 42.0 W/K, 14.0 W/K, and 7.9 W/K at 16 °C, respectively. The relationships between the overall thermal benefits of four devices and operating parameters were established to obtain the lower thresholds and suggested values of the heating parameters under different cold conditions. Advice on the automatic control for PHDs was proposed, including the limited air temperature for activation authority, activation priority order in the multi-device scenario, and initial heating settings. Integrating automated PCS with existing building management systems can achieve microenvironmental management, enhancing comfort and energy conservation.

Energy efficiency and environmental regulations for mitigating carbon emissions in Chinese Provinces

Taking into account the contributions of economic performance (GDP), urbanization (URB), industrial structure (IND), and renewable energy consumption (REC), this paper examines the impact of green technology innovation (GTE), energy efficiency (EF), and environmental regulation (ER) on CO2 emissions in Chinese provinces from 2010 to 2020. Using the GMM method for the initial estimation, the MMQR as 2nd generation test for robustness and innovative panel causality presented by the JKS test, we have found: 1) a one percent boom in GDP is linked with a 0.08% upward push in CO2 emissions throughout 30 provinces in China. 2) the renewable energy and energy efficiency data seems to effectively decrease CO2 emissions, with a more pronounced impact observed at the upper quantile. 3) The environmental policy is limited across all quantiles. The study examines novel implications regarding sustainable development and carbon neutrality objectives.

Analytical model and comprehensive index construction of indoor air purification effect based on dynamic characteristics and energy efficiency

Meeting environmental regulation requirements while improving energy usage efficiency are crucial endeavors to achieve decarbonization and indoor environmental regulation. In this study, experimental testing, data analysis, and modeling are performed for the dynamic purification process of indoor PM2.5 (fine particulate matter) in the context of regulating the indoor environment of buildings. The results show that indoor PM2.5 levels are dynamically matched to the outdoor environment state and the requirements of environmental control. An analytical model of the effect of PM2.5 purification is constructed, which can accurately reflect the dynamic changes in the PM2.5 mass concentration during the indoor air purification process considering the outdoor PM2.5 concentration and the purification efficiency of the purification filters and purification systems, thus supporting the prediction of purification outcomes and accurately constraining the actual indoor air quality purification process. Meanwhile, an indoor air quality control index (IAQCI) is established based on the purification effect and purification energy efficiency under various combinations of air filters and purification systems. This approach is used to quantitatively assess the dual control of energy efficiency and environmental regulation, as well as the purification effect and efficiency of indoor purification schemes based on outdoor dynamic PM2.5 conditions.This study provides a set of innovative and feasible research methods for realizing comprehensive indoor environmental performance evaluations of buildings.

Environmental consequences in lifecycle changes of container shipping vessels

To estimate the average lifespan of container vessels, this study specified their most suitable lifespan distribution function using a comprehensive dataset comprising 2188 container vessels manufactured and retired between 1941 and 2018. The lifecycle CO2 emissions of vessels were estimated under different scenarios with varied average lifespans and average carbon intensity improvements per annum through stock-flow model analysis. The results indicated that a normal distribution best represented the lifespan distribution of container vessels, with an estimated average lifespan of approximately 24 years. Furthermore, scenario analyses revealed that shortening the lifespans of container vessels can effectively reduce lifecycle CO2 emissions. This study demonstrates the synergistic contribution of accelerating the replacement cycle of container vessels and implementing stronger energy efficiency regulations for emissions reduction, highlighting the importance of policies regulating vessel lifespans.

How does factor market distortion affect green innovation? Evidence from China's sustainable development demonstration belt

AbstractGreen innovation meets the simultaneous demands of green and innovation‐driven development models when it is deemed as a key to realizing a green economic transition. However, factor market distortion impedes China's green development through factor mobility and resource allocation. Under such circumstances, we detect whether and how factor market distortion affects green innovation from various perspectives in the case study of China's Sustainable Development Demonstration Belt. The findings demonstrate that the distortion has a pronounced inhibiting effect on the green innovation growth in the study area. For the eastern and more‐developed cities, factor market distortion considerably inhibits green innovation improvement, while the impact is less pronounced in the western (or central) and less developed cities. Furthermore, the factor market distortion negatively affects green innovation through some effective paths, like energy efficiency and environmental regulation. From a spatial perspective, the green innovation's spillover effect could be reduced by both the distortions of the labor market and capital market. Thus, this study would provide strong theoretical support for enhancing the factor market system and improving the multiregional green innovation power in China, as well as scientific suggestions on transitioning to China's sustainable development.

Numerical study of thermal comfort and energy efficiency about electrically heated footwear under a cold environment

PurposeThe paper aims to reveal the relationship among energy efficiency, thermal comfort and thermal regulation of electrically heated footwear and to investigate influencing factors on the energy efficiency and thermal comfort.Design/methodology/approachA finite volume model was proposed to simulate the two-dimensional heat transfer in electrically heated footwear (EHF) under an extremely cold condition. The model domain consists of three-layer footwear materials, a heating pad, a sock material, an air gap and skin tissues. Model predictions were verified by experimental data from cold-contact exposure. Then the influencing factors on the energy efficiency and thermal comfort were investigated through parametric analysis.FindingsThe paper demonstrated that the skin temperature control (STC) mode provided superior thermal comfort compared to the heating pad temperature control (HPTC) mode. However, the energy efficiency for the HPTC mode with a heating temperature of 38 °C was 18% higher than the STC mode. The energy efficiency of EHF while reaching the state of thermal comfort was strongly determined by the arrangement and connection of heating elements, heating temperature, thickness and thermal conductivity of footwear materials.Originality/valueThe findings obtained in this paper can be used to engineer the EHF that provides optimal thermal comfort and energy efficiency in cold environments.

A performance evaluation method for energy storage systems adapted to new power system interaction requirements

In recent years, China’s new energy storage application on a large scale has shown a good development trend; a variety of energy storage technologies are widely used in renewable energy development, consumption, integrated intelligent energy systems, distribution grids, and microgrids; and substantial progress has been made in the research and development of technology and equipment, construction of demonstration projects, exploration of business models, and construction of standard systems. Up to now, a unified statistical index system and evaluation method standard for new energy storage has not yet been formed domestically or even internationally. The work takes the status quo of the new power system construction of the Hebei South Network as the research object and carries out research on the new energy storage statistical index system and evaluation method. It constructs a new energy storage power station statistical index system centered on five primary indexes: energy efficiency index, reliability index, regulation index, economic index, and environmental protection index; proposes Analytic Hierarchy Process (AHP)–coefficient of variation combination assignment method; and evaluates the development level of the new energy storage power station by adopting a comprehensive evaluation model based on the object element topology method. The new energy storage statistical index system and evaluation method are designed to provide a scientific index system and evaluation method for comprehensively monitoring, assessing and measuring the comprehensive performance and effect of new energy storage power plants in the process of operation and development, and optimizing the operation strategy of new energy storage power plants as well as the development and promotion of energy storage technology.

Influence of Balcony Thermal Bridges on Energy Efficiency of Dwellings in a Warm Semi-Arid Dry Mediterranean Climate

Thermal bridges significantly influence the energy performance of buildings. However, their impact varies depending on the type of thermal bridge, climate conditions, construction methodologies, and geometric characteristics of the building. On the Spanish Mediterranean coast, buildings with large balconies are predominant. Nevertheless, the Spanish energy efficiency regulations do not adequately specify the thermal bridges at the junctions of balconies with facades, leading to a lack of consideration for their influence in the majority of architectural projects. The objective of this study is to qualitatively and quantitatively assess the impact of such thermal bridges on the energy efficiency of buildings in a dry Mediterranean climate (BShs) within a warm semi-arid climate (BSh). As a case study, the influence of this thermal bridge is analyzed in two residential buildings located on the Mediterranean coast of southeastern Spain. The study also examines the modification of various construction parameters of this thermal bridge and determines the optimal design parameters to reduce its thermal transmittance. The results demonstrate that the energy needs caused by thermal bridges account for approximately 40% of the total annual energy needs of the studied residential buildings. Balcony thermal bridges account for 25% to 40% of the energy needs caused by all thermal bridges. The lack of differentiation in Spanish standards between balcony–facade and facade–slab edge junctions causes an imprecision in calculations equivalent to 12% of the total annual energy needs of dwellings. The novelty of this research lies in highlighting that current regulations and calculation programs need improvement to better characterize balcony thermal bridges and enhance the accuracy of building energy efficiency calculations.

Synergistic effects of pollutant control: Evidence from China's sulfur dioxide emission control policy

This study investigates the impact of China's national sulfur dioxide emission control policies on carbon dioxide emissions. Using the difference-in-difference-in-differences (DDD) estimation method, we analyze the synergistic effects of environmental regulations on pollution control and carbon emission reduction. Empirical findings demonstrate that sulfur dioxide emission regulations have a significant effect on reducing firms' carbon dioxide emissions, primarily through energy conservation measures. Furthermore, results reveal variations in the effectiveness of these regulations across different types of firms and regions. Specifically, state-owned and large-scale firms, along with those situated in the eastern and central regions of China, exhibit greater energy-saving and emission-reducing effects in response to the regulations. Notably, these regulations lead to unexpected energy savings and emission reductions without compromising output, highlighting improvements in energy efficiency as a key driver. These findings underscore the importance of recognizing the potential synergies between pollutant control policies and carbon emission reduction goals. To maximize these positive effects, policymakers should prioritize strategies to enhance energy efficiency and tailor environmental regulations to suit the unique characteristics of firms and regions. Overall, this study contributes valuable insights to the development of effective environmental policies in the context of carbon peaking and neutrality objectives of China.

Experimental assessment of impact of different ventilation modes on cognitive and academic performance: A study based on classrooms in Türkiye

In closed spaces, such as classrooms, poor ventilation, indoor exposure to CO2, and non-optimal humidity and temperature conditions are global concerns associated with health and performance. This study experimentally assesses the effects of different ventilation modes on the air quality parameters and cognitive and academic performances of 120 s-grade primary school children in two buildings with different characteristics during heating and non-heating seasons. Based on a retrospective analysis of 455 primary schools in Türkiye during 2017–2018, the study was conducted in six classrooms of the two representative school buildings. Indoor air quality monitoring and performance (of the students) assessment was carried out from December 9, 2019, to September 28, 2020. The non-heating season measurements were conducted during the COVID-19 pandemic. According to our findings, the traditionally constructed school without energy efficiency regulations exhibited the worse scenario. The success percentages of arithmetic attention in both traditional and natural ventilation modes were significantly lower in the non-heating season than in the heating season, which indicates the impact of using a facemask inside a classroom during cognitive tasks. This study demonstrated that the heating season is more critical than the non-heating season in terms of ventilation of closed spaces.

Research on the effect of the refrigerant charge in a variable capacity heat pump

Current energy efficiency regulations have led to the development of heat pumps equipped with variable speed compressors (VSC) and electronic expansion valves (EEV). To reduce the amount of refrigerant charge, heat pump manufacturers are developing units without a liquid receiver. As a result, the amount of refrigerant charge has a direct impact on the unit performance and needs to be optimized. Previous studies have shown the existence of an optimum refrigerant charge that maximizes the COP at a given operating condition. However, with VSC it is not clear if the optimum charge at a given compressor speed is the adequate one at other speed values. This paper analyzes the effects of the refrigerant charge amount on the performance of a brine-to-water heat pump equipped with a VSC and an EEV. For a given compressor speed, the variation of the COP with the charge showed similar trends and an optimum refrigerant charge could be identified. The charge for the maximum COP changes slightly with the compressor speed. The seasonal coefficient of performance (SCOP) is proposed as a better metric for evaluating the optimum charge. Results show that the SCOP is quite stable with the refrigerant charge.

Integrating machine learning and IoT into apiary management to optimize bee health and production

This article discusses integrating machine learning and IoT technologies into bee apiary management systems. The research aims to optimize bee conditions, improve their health and increase honey production. Using machine learning, large amounts of data collected by hive sensors are analyzed to predict and prevent various bee health problems effectively. Particular attention is paid to methods of controlling temperature in hives through pulse-width modulation technology, which provides accurate and energy-efficient regulation of temperature conditions. A method for predicting temperature in hives for effective apiary management is also proposed.

Assessment of the Robustness of the European Gas System to Massive Gas Outages and Evaluation of the Effect of Increased Energy Efficiency on the Security of Gas Coverage in Different Countries

The aim of this paper is to simulate the European natural gas system in extreme situations and to determine its weaknesses in terms of demand coverage. An assessment has also been made of the targets set for existing energy efficiency regulations and their effects on the coverage of future natural gas demand. This document assesses the potential for energy efficiency improvements associated with European countries and the effect of such improvements on the lessening of the natural gas demand. Once the efficiency improvement potential has been identified, the results of demand coverage in various scenarios of natural gas supply cut-off via pipelines were studied. The expected result reflects the study of the effect of the presumed demand reduction, due to the improvement of energy efficiency, on the self-sufficiency of the natural gas network and the improvement of energy coverage for EU countries. To carry out this study, an evaluation of the current infrastructures was developed, the existing resources were optimized, and the independence of the system was quantified in relation to the current situation of natural gas consumption at the European level. The proposed model has resulted in improvements in the coverage of the demand of certain countries and has detected those with systems that are not robust enough to face extreme crisis situations. The main conclusions are that the natural gas system has improved considerably from 2009 to the present, and that, in the event of massive gas cuts, there is a real risk of being unable to cover the natural gas demand of several countries with a very high dependence on gas from Russia.

RATIONAL MODES OF GAS TRANSPORT SYSTEMS IN THE CONDITIONS OF UNSTATIONARY GAS TRANSPORT

The problem of rational regulation of the operation modes of the gas transportation system, which is operated in conditions of non-stationary gas transportation, is considered. An assessment of the mathematical modeling of non-stationary processes in complex gas transport systems with uneven gas consumption and diversification of sources of energy supply is given. Based on analytical studies, recommendations are made on the influence of various parameters on the efficiency of compressor station operation. Dependencies are obtained that express the nature of gas transport process control, which can be applied in each specific case to determine the response of the system to a change in the control factor. Modeling of non-stationary objects of gas transport systems should be carried out using an adaptive linearized system, which implements the principle of energy-efficient regulation, i.e. it allows to specify the parameters of the technological object and control its operation at the same time. As the analysis showed, the given technological constraints on pressure are presented in terms of changes in productivity and can be combined with constraints on the productivity of the compressor station. The obtained limits of technological admissibility for the average daily gas consumption are not constants, but some functions of time, the behavior of which is determined by the nature of gas consumption. The use of the specifics of the interrelationship of restrictions caused by the technology of gas transport, in order to build simpler algorithms for its solution, made it possible to create a methodology for forecasting the system's operating modes in conditions of non-stationary gas consumption.

Metamodel to predict annual cooling thermal load for commercial, services and public buildings: A country-level approach to support energy efficiency regulation

The energy sector significantly impacts the environment, with energy production contributing to greenhouse gases emissions and climate change. In Brazil, buildings account for a substantial portion of energy consumption, making energy efficiency essential for sustainable development. Building simulation is an efficient way to provide valuable insights into the thermal performance of buildings, but it requires expertise, time, and computational resources. To overcome these simulation constraints, metamodeling has emerged as an easy-to-use and fast-response alternative to analyse the thermal performance of buildings. This study focuses on developing a metamodel to predict cooling thermal loads in Brazil's commercial, services, and public buildings, supporting the country's building energy efficiency labelling program. It is expected from the metamodel a high capacity to reproduce the variability of climates, contexts, and heterogeneity of buildings from a country-level perspective. A parametric sampling process was used to develop a comprehensive simulated database considering several variations of building-related, occupancy patterns, and weather parameters. The metamodel was trained, validated and tested using optimisation techniques and an artificial neural network. Afterwards, it was compared with actual models, considering different typologies and climates. While the metamodel demonstrates high accuracy and generalisation, limitations were found regarding its application in warmer temperatures and complex building shapes. Further refinement is needed to improve its applicability and reliability in real-world scenarios. The proposed metamodel offers a practical and widely applicable tool for supporting energy code compliance and energy efficiency assessment in buildings.

Energy Demand Reduction: supply chains and risk analysis

Demand Reduction is a strategy with the potential to make a significant contribution to the energy supply/demand balance. Its two major themes are improving the energy efficiency of devices (appliances and processes) and changing people’s behaviour towards using less energy. In our analysis of a nation’s energy security, we treat Demand Reduction as an additional fuel which delivers ‘negafuel’, allowing a particular level of energy services to be met at a lower volume of supply than would be possible in its absence. In common with other fuels, negafuel is delivered by a supply chain with linked stages, all encountering risks of various types. A comprehensive survey of these risks in a case study of the UK shows that Demand Reduction belongs to a middle-ranking group of fuels in terms of overall risk. High-level risks encountered include the difficulty of assessing and delivering potential energy savings, the rate of building construction at the highest energy efficiency standards, optimism bias, changing policy and regulation, and operational failure (both of technology and policy). Assessing the risk of Demand Reduction as a supplied negafuel focuses attention on specific risks requiring mitigation, facilitating design of better policy, and more effective commercial products.

A game-theoretic approach to designing carbon regulations in a duopoly freight transportation market: Road and multimodal road-rail competitive systems.

Since the transportation industry produces remarkable carbon emissions worldwide, governments aim to curb these emissions by implementing different carbon regulations. However, little is known regarding how the heterogeneity of transportation systems should be exploited to design carbon regulations. To fill this research gap, the present article formulates carbon cap-and-trade and carbon offset regulations to reduce total carbon emissions produced by road and multimodal road-rail freight transportation systems (FTSs) in a duopoly market; the latter is regarded as a green, energy-efficient transportation mode. A novel procedure is suggested to allocate initial carbon caps that is a hybrid of both benchmark and grandfathering methods. The procedure allows the government to exploit the energy efficiency of the multimodal system, when targeting a reduction of total carbon. Then, a game-theoretic approach is adopted to implement the mentioned carbon regulations. A government, as a Stackelberg leader, maximizes a social welfare function containing economic, social, and environmental dimensions. Under the cap-and-trade regulation, a Nash bargaining process is proposed to trade carbon permits between the FTSs, as the followers, for updating their initial caps. The equilibrium outputs of the two mentioned carbon regulations and a carbon tax regulation are compared. The findings based on an experimental analysis suggest that the cap-and-trade (carbon offset) is the optimal and energy-efficient regulation from the social (economic or environmental) perspective. In terms of policy implications, our findings indicate that the development of a marketplace infrastructure for trading carbon permits is not justifiable under theeconomic and environmental perspectives of the government.

Energy efficiency initiatives and regulations for commercial buildings in India: a review

Energy efficiency initiatives and regulations for commercial buildings in India: a review

Investigation of the Effect of Anti-fouling Systems on Meeting Energy Efficiency Regulations

The operational efficiency of marine vessels should be kept as high as possible to achieve sustainable development goals in the maritime field. However, a lot of factors such as resistance components reduce the operational efficiency of the ship. Frictional resistance is the biggest resistance component for the power needed on ships and its coefficient increases due to the biofouling as long as the ship interacts with seawater. The increased total resistance of the ship causes extra power needed and excessive fuel consumption to reach service speed. The increase in both fuel consumption and power will create an obstacle to meeting the EEXI and CII reference values which became mandatory after January 1, 2023. That’s why the utilization of effective anti-fouling systems is quite critical in maritime applications. The purpose of this study is to reveal anti-fouling systems’ effect on EEXI, CII, and CII ratings by utilization of the container ship operated in liner shipping. That’s why, high, medium, and low effective anti-fouling system scenarios have been created since the effect of each anti-fouling will not be the same on the container ship. According to the results, the required EEXI and CII reference values will have been met respectively when the effect of ship biofouling is ignored. However, the reduction ratios and biofouling effect have created quite a challenge in meeting EEXI and CII in the following years. Although the required EEXI value has been met for 2024 and 2025 by the high-effective anti-fouling system and reference value has not been met by the low-effective anti-fouling system in the following years. Any anti-fouling system utilized in this paper won’t be sufficient to meet the reference value at the end of 2023 because attained CII of the container ship is very close to the reference value of CII in 2023. The CII rating of the container ship will have been at C level until the end of 2026 when the biofouling effect is ignored. However, it decreased to D and E levels in the following two years depending on the best and worst scenarios. This study will be a valuable resource for scientists, researchers, experts, and maritime stakeholders who want to investigate the effect of EEXI, CII, and CII rating of antifouling systems.