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The current investigation examines the experimental and energyconservation analyses of 17.5 kW cooling capacity of a groundsource heat pump (GSHP) system and an air-source airconditioning system (ASAC) of the same cooling capacity. Using experimental data and a sensitivity technique, the thermal efficiency of both the systems were evaluated. During the experiments conducted for cooling period in June 2022, the data for six-day operation were collected and the coefficient of performance of both the systems were evaluated. Notably, the GSHP system exhibited an average cooling capacity of 10 to 15 kW, whereas the ASAC maintained a range of 9 and 13 kW. The coefficient of performance (COP) for the GSHP system was obtained as 3.8, while the ASAC system COP was 2.9. The results indicate that the use of GSHP system results in an energysaving of 10–40% in comparison to the ASAC system. Moreover, the present study included uncertainty and propagation analyses, along with sensitivity evaluations, with the objective of identifying the most influencing parameter on the derived parameters. Sensitivity analysis indicates outlet temperature of air from the evaporator is the most influencing parameter for the performance of both the systems. [ABSTRACT FROM AUTHOR]

The transport sector accounts for around 30 % of Europe’s final energy consumption. To meet the EU’s decarbonization goals by 2050, it is important to quantify the energy savings potential in technology, infrastructure, and planning. This study analyses the European transport sector in the context of traditional and energy-efficient urban development. The latter demonstrates a scenario where accessibility is provided through enhanced proximity to a destination rather than through increased mobility, where mobility is shifted from roads and aviation towards rail. This development is ensured by, among other things, investing heavily in urban and inter-urban transport systems and abstaining from building new freeways and airports. The results indicate that it is not only desirable but economically beneficial to shift towards an energy-efficient transport system. The development of the European transport sector in the proposed trajectory significantly reduces annual final energy demand, and the investment made in new infrastructure for rail, bikes, and walkable urban areas are paid back by the reduced cost from road transport.

• Energy-efficient retrofitting of existing buildings. • Using a new metaheuristic called Modified Supply-Demand-based Optimization Algorithm. • Multi-objective optimization method for decision-making. • Maximizing energy-savings and Minimizing payback period. Investing in energy-efficient retrofitting of existing buildings requires a robust decision-making framework. This study develops a multi-objective optimization technique to assist designers in minimizing payback time and maximizing energy savings within a specified initial investment. The proposed method utilizes a novel metaheuristic, the Modified Supply-Demand-Based Optimization Algorithm (MSDOA), to achieve optimal decisions. The model was tested on nine case studies involving buildings with various facilities, demonstrating its effectiveness. For example, an investment of $190,000 resulted in a payback period of less than three years and energy savings of over 10 % of the baseline consumption. The model considers initial investment, net present value (NPV), payback period, and energy targets as constraints. To evaluate the model's robustness, a sensitivity analysis was performed, examining the impact of varying initial investments, energy savings miscalculations, auditing errors, changes in electrical power costs, and interest rates. The results indicate that higher investments consistently lead to increased energy savings, though the payback period may vary. The MSDOA showed superior convergence speed compared to other algorithms, ensuring more reliable and accurate optimization outcomes. This study confirms the validity of the proposed design and highlights its potential for significant energy savings and financial benefits in building retrofitting projects. [ABSTRACT FROM AUTHOR]

An embedded level-shifting (ELS) dual-rail SRAM is proposed to enhance the availability of dual-rail SRAMs. Although dual-rail SRAM is a powerful solution for satisfying the increasing demand for low-power applications, the enormous performance degradation at low supply voltages cannot meet the high-performance cache requirement in recent computing systems. The requirement of many level shifters is another drawback of the dual-rail SRAM because it degrades the energy-savings. The proposed ELS dual-rail SRAM achieves energy-savings by using a low supply voltage to precharge bitlines while minimizing the performance overhead by appropriately assigning a high-supply voltage to critical circuit blocks with effective level-shifting circuits. The sense amplifier embeds a level-shifting operation, thereby operating with a high supply voltage for a fast sensing operation. The proposed dynamic output buffer resolves the potential static current problem and improves the read delay. The number of level shifters is reduced using a proposed write driver, which conducts level-shifting and write-driving simultaneously. The proposed ELS dual-rail SRAM achieves low-power operation with 71.4% power consumption compared to single-rail SRAM with 72% performance overhead in circuit-level simulation, while the previous hybrid dual-rail SRAM shows 67.8% energy consumption with 270% performance overhead. In architecture-level simulation using Gem5 simulator with SPEC2006 benchmarks, the system with the ELS dual-rail SRAM caches shows, on average, 29% performance improvement compared to that of the system with the hybrid dual-rail SRAM caches.

In work it is proved that for creation of a real resource reserve of the organization full and unconditional performance of tasks in view on increase of power efficiency of all industrial and housing-and-municipal complexes, all-round studying of principles and methods of realization of problems in the field of power efficiency in regions is necessary. The special attention in article is given interrelation between cluster to the self-regulating organization in the field of power audit, the power service companies and the enterprises of a power effective orientation, sources of their financing.

This work aims at answering the question–to what extent thermally compliant buildings are involved in ensuring the winter indoor thermal comfort of occupants in cold semi-arid climates in Morocco. Real-time monitoring of a new-built university building located in eastern Morocco was conducted. The good agreement between the measured and simulated temperatures of the case study building confirmed the accuracy of the developed model. Thereafter, the thermal performance of different external wall configurations was investigated. The results show that compliant buildings guarantee better comfort conditions in winter by passively increasing the indoor air temperature by up to 2 °C, resulting in a maximum percentage of dissatisfaction of less than 13%. The winter discomfort hours based on a temperature set point of 16 °C are reduced by 95% compared to typical buildings. Moreover, the thermal compliance of buildings significantly reduces the daily air temperature amplitude, leading to a periodic dynamic behaviour without peak loads, which could be effective for the building energy management. The efficacy of earthen walls in regulating indoor temperatures was also confirmed due to the excellent thermal inertia of earth. For optimum winter comfort (20 °C), the implementation of the Moroccan building energy code shows up to 72% of reduction in heating demand when applied to conventional buildings.

In the article social essence of energy, her value, opens up for modern society. Going is investigated near determination of concepts «energy–safety» and energy «efficiency» in the context of concept «National safety». The mechanisms of the use of energy are analyzed as a political and economic lever of pressure on an international scene. Risk factors that is related to power dependence of modern Ukrainian society are analyzed. The ways of their overcoming and consolidation of Ukrainian society offer through converting of energy into the article of consumption. [ABSTRACT FROM AUTHOR]

Purpose is to explore the practical experience of forming of organizationally economic mechanism to ensure energy safety based on principles of energy conservation and efficiency of fuel and energy resources use in Ivano-Francovsk city.Methodology includes мethods of synthesis, induction, deduction, analogy, wich used in the study.Results. The active policy of energy efficiency and conservation provides the increase of power safety of city's economy due to reduction of dependence on the consumption of separate types of non-renewable fuel and energy resources. The involvement of international organizations increased the possibility of financing the development and implementation of energy saving measures and improvement of the energy ensuring of the city.Conclusions. A number of organizational and economic problems to ensure power safety are solved by joining the «Agreement of Mayors on sustainable development and climate protection» and the development of Sustainable Energy Programme for 2013 - 2020 years, which includes measures to reduce carbon dioxide emissions by 20 % and local production and consumption of energy. However the efficiency of energy-saving measures and technologies of renewable energy by lowering the price of natural gas is significantly reduced, which leads to increase the payback period almost doubled. Therefore it is necessary to provide administrative and financial leverage to introduce energy-saving technologies: renewable energy in the construction of housing, financial sanctions for excessive fuel consumption and energy and for production of energy-intensive equipment, environmental penalties for exceeding norms of greenhouse gases and others.Practical implications. The introduction of the mentioned incentives needs the development of the legislative and regulatory support and study the experience of the European countries in their use.Purchase on Elibrary.ru > Buy now

The Inter-Regional Input Output (IRIO) model is developed in 11 manufacturing sectors of China's 30 provincial-level regions. Against the background of electricity pricing and energy-savings, this paper develops and compares the relative sectoral and regional price sensitivities to electricity price and elasticities to electricity demand. The results show that industries such as metal smelting, oil and chemical processing are more sensitive to increasing electricity prices, and have a higher potential of energy-savings. Remarkable findings hold for the regions of Tianjin, Hebei, Jilin, Guangdong, Zhejiang, Shaanxi and Shandong. [ABSTRACT FROM AUTHOR]

Green roofs may be considered a passive energy saving technology that also offer benefits like environmental friendliness and enhancement of aesthetic and architectural qualities of buildings. This paper examines the energy and economic viability of the green roof technology in the hot humid climate of Saudi Arabia by considering a modern four bedroom residential building in the city of Dhahran as a case study. The base case and green roof modelling of the selected building has been developed with the help of Design Builder software. The base case model has been validated with the help of 3-month measured data about the energy consumption without a green roof installed. The result shows that the energy consumption for the base case is 169 kWh/m² while the energy consumption due to the application of a green roof on the entire roof surface is 110 kWh/m². For the three investigated green roof options, energy saving is found to be in the range of 24% to 35%. The economic evaluation based on the net present value (NPV) approach for 40 years with consideration to other environmental advantages indicates that the benefits of the green roof technology are realized towards the end of the life cycle of the building. [ABSTRACT FROM AUTHOR]

• Indoor thermal environment and AC usage behavior was investigated for low-quality centrally heated dwellings. • 90% of AC trigger temperature is 15 ℃ for the living room and 14 ℃ for the bedroom. • The heating demand drivers of cool housing are identified by heteroskedasticity-robust Ordinary Least Square. • The study presents new knowledge for appropriate way to meet actual heating demand while reducing energy use. • Relationships between indoor temperature, heath and energy use are discussed. In northern China, district heating systems without terminal control typically serve thousands of end-users, thus inevitably some users suffer from insufficient warmth and others are overheated indoors due to hydraulic imbalances. This paper aimed to understand the indoor thermal conditions and the actual heating demand in low-quality centrally heated dwellings. The driving force of heating demand was analyzed based on a smartphone survey of 233 households in cold climates, and field measurements of winter indoor thermal environment and AC supplemental heating behavior were conducted in a sample of 13 cool dwellings. Logistic regression and heteroskedasticity-robust Ordinary Least Squares were adopted to assess AC usage patterns and driving forces of heating demand, respectively. New knowledge has been gathered regarding average temperatures of 17.4 ℃ and 16.8 °C in cool housing living rooms and bedrooms, respectively, outside the human thermal comfort zone. Simultaneously, intermittent and partial AC usage patterns induced by time and air temperature were observed in these cool end-users for the comfort. The average daily running time of AC devices was 2.0 h for the living room and 1.8 h for the bedroom. There were statistically significant base linking occupants' heating demands to education level, household income, tenure type, presence of children, thermal experience and heating system. However, it was not a significant factor for household size. In addition, a rebound effect of building energy efficiency improvements on the interior temperature was also noticed. The results of this study shed light on better and target-oriented residential internal temperature or heating system design for both thermal comfort requirements and energy-savings. [ABSTRACT FROM AUTHOR]

In this paper, we build a model of energy-savings and emission-reductions with two delays. In this model, it is assumed that the interaction between energy-savings and emission-reduction and that between carbon emissions and economic growth are delayed. We examine the local stability and the existence of a Hopf bifurcation at the equilibrium point of the system. By employing System Complexity Theory, we also analyze the impact of delays and the feedback control on stability and entropy of the system are analyzed from two aspects: single delay and double delays. In numerical simulation section, we test the theoretical analysis by using means bifurcation diagram, the largest Lyapunov exponent diagrams, attractor, time-domain plot, Poincare section plot, power spectrum, entropy diagram, 3-D surface chart and 4-D graph, the simulation results demonstrating that the inappropriate changes of delays and the feedback control will result in instability and fluctuation of carbon emissions. Finally, the bifurcation control is achieved by using the method of variable feedback control. Hence, we conclude that the greater the value of the control parameter, the better the effect of the bifurcation control. The results will provide for the development of energy-saving and emission-reduction policies. [ABSTRACT FROM AUTHOR]

This paper presents a simulation environment and daylighting control strategy to achieve energy-efficient lighting while providing desired lighting levels at the target points. The lighting strategy is based on a self-tuning multivariable controller, which maintains the illuminance levels at user-defined set-points while improving the energy consumption due to artificial lighting. The simulation environment utilizes the so-called layered lighting design, which allows one to evaluate the performance of different control strategies. Furthermore, the environment can be used to validate the performance of a lighting control strategy, in quasi-real-time, and assess its potential energy savings. The above approach has not been investigated in prior literature and may thus be of interest in energy-aware automated lighting systems. A case study is presented for an open-plan office space exposed to variable natural light through windows and a set of individually addressable light emitting diode luminaries. [ABSTRACT FROM PUBLISHER]

Green roofs may be considered a passive energy saving technology that also offer benefits like environmental friendliness and enhancement of aesthetic and architectural qualities of buildings. This paper examines the energy and economic viability of the green roof technology in the hot humid climate of Saudi Arabia by considering a modern four bedroom residential building in the city of Dhahran as a case study. The base case and green roof modelling of the selected building has been developed with the help of DesignBuilder software. The base case model has been validated with the help of 3-month measured data about the energy consumption without a green roof installed. The result shows that the energy consumption for the base case is 169 kWh/m2 while the energy consumption due to the application of a green roof on the entire roof surface is 110 kWh/m2. For the three investigated green roof options, energy saving is found to be in the range of 24% to 35%. The economic evaluation based on the net present value (NPV) approach for 40 years with consideration to other environmental advantages indicates that the benefits of the green roof technology are realized towards the end of the life cycle of the building.

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Copyright of Technical Transactions / Czasopismo Techniczne is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose. Determination of the optimal decisions in development and realization of the energy-saving programs for operating pharmaceutical productions. Methodology. There was the conducted analysis of well-known decisions of optimization of energy consumption and energy-savings in the process of production of medicinal facilities. The events on an energy-savings, undertaken on the operating enterprises of home industry, are studied. The newest pharmaceutical technologies on apparatus registration of process of production of hard and liquid medicinal forms, possibilities of barrier technologies in the decision of questions of energy-savings by comparison to technology of clean apartments of firstgenerations are considered. Findings. Basic measures on reduction of energy consumptions during exploitation of the systems of ventilation and condition of clean rooms are determinated: the use of recurcular air, adjusting of his correlation with air from outside, minimization of resistance of stream in the system of circulation of air by the choice of low speeds, smooth connections, absence of dramatic changes of speed and other similar actions. Perspective direction of the cost of electric energy and increase of power efficiency of pharmaceutical productions cutting is application of RABS passive and active types and insulators. The insulators, equipped by the autonomous system of circulation of air, allow to shorten most running expenses in comparison as with RABS so with the clean rooms of first generations. The use of insulators gives an opportunity to bring down the level of cleanness of production area to the class C and, accordingly, decrease energy consumptions on the system of ventilation and conditioning of apartment. Originality. Generalization of the existent decisions of energy-savings and determination of the most effective ways of optimization of energy consumptions on the enterprises of domestic pharmaceutical industry. Practical value. Research results are of interest for specialists on questions energy-savings in the search of optimal decisions of increase of power efficiency of enterprises and specialists on planning of pharmaceutical productions on the base of the newest technologies of productive process organization. [ABSTRACT FROM AUTHOR]

Traditional data acquisition methods for wireless sensor networks (WSNs) require all sensor nodes to transmit at least once to the sink node to obtain a full view of the network. In this paper we present Disagree, a different data acquisition method to retrieve data in WSNs that works in the opposite way as compared with traditional methods. In Disagree, only nodes that do not satisfy an assertion are required to transmit data back to the sink node in order to obtain a complete view of the network. We show that this behavior is the base of an energy-efficient way to gather all data. An important feature of Disagree is that it saves energy at the sensor level by exploiting data correlation. Rather than requesting explicit data readings from all sensor nodes, Disagree estimates the readings from sensor nodes that did not respond to the assertion. As a result of this policy, Disagree can obtain a view of the sensing field with different levels of resolution involving the transmission of only a subset of the sensor nodes by exploiting spatial data redundancy. We implemented Disagree in NS-2 network simulator and results indicate Disagree can significantly reduce the percentage of nodes replying to queries compared with flat and a cluster head based approaches. [ABSTRACT FROM AUTHOR]

Abstract: Energy-efficient lighting is one of the key measures for addressing electric power shortages and climate change mitigation, and fluorescent lamps are expected to dominate the lighting market in China over the next several years. This review presents an overview on the emissions and risk of mercury from fluorescent lamps during production and disposal, and discusses measures for reducing the mercury risk through solid waste management and source reduction. Fluorescent lamps produced in China used to contain relatively large amounts of mercury (up to 40mg per lamp) due to the prevalence of liquid mercury dosing, which also released significant amounts of mercury to the environment. Upgrade of the mercury dosing technologies and manufacturing facilities had significantly reduced the mercury contents in fluorescent lamps, with most of them containing less than 10 or 5mg per lamp now. Occupational hygiene studies showed that mercury emissions occurred during fluorescent lamp production, particularly in the facilities using liquid mercury dosing, which polluted the environmental media at and surrounding the production sites and posed chronic health risk to the workers by causing neuropsychological and motor impairments. It is estimated that spent fluorescent lamps account for approximately 20% of mercury input in the MSW in China. Even though recycling of fluorescent lamps presents an important opportunity to capture the mercury they contain, it is difficult and not cost-effective at reducing the mercury risk under the broader context of mercury pollution control in China. In light of the significant mercury emissions associated with electricity generation in China, we propose that reduction of mercury emissions and risk associated with fluorescent lamps should be achieved primarily through lowering their mercury contents by the manufacturers while recycling programs should focus on elemental mercury-containing waste products instead of fluorescent lamps to recapture mercury from the waste stream cost-effectively. [Copyright &y& Elsevier]

Improving the efficiency of the manufacturing process is one of the ways to resolve the ecological issues, cost-saving pressure, and new environmental legislations. This paper presents the study on the in-line induction heating process prior to hot forging of an automotive crankshaft in order to find the potential solutions for improving the energy efficiency. The heating strategy that divides the induction heating line into groups for flexible control and saving operating energy was introduced. Optimization of the operating parameters of the induction heating system, including voltages and frequencies, was done using design of experiment in conjunction with numerical simulation, approximation, and genetic algorithm optimization techniques. In addition, thermal insulation was proposed to reduce the heat losses. The research results show that the energy can be saved through process parameter optimization approximately 6%. Furthermore, if the insulating covers at the open spaces between adjacent heaters are used, roughly 4% of additional amount of the energy consumption can be reduced. [ABSTRACT FROM AUTHOR]

Abstract: Improvement of residential environments has recently been promoted by the Korean government as part of its energy-saving measures. The objective of this research is to develop a decision support model for selecting the multi-family housing complex with the potential to be effective in saving energy. In this research, 362 cases of multi-family housings located in Seoul were selected to collect characteristics and data on gas energy consumption from 2009 to 2010. The following were carried out: (i) using the Decision Tree, a group of multi-family housings was established based on gas energy consumption; (ii) using case-based reasoning, a number of similar multi-family housings were retrieved from the same group of multi-family housings; and (iii) using a combination of genetic algorithms, artificial neural network, and multiple regression analysis, prediction accuracy was improved. The results of this research can be useful in the following: (i) preliminary research for continuously managing the gas energy consumption of multi-family housings; (ii) basic research for predicting gas energy consumption based on the characteristics of multi-family housings; and (iii) practical research for selecting an optimum multi-family housing complex (with the potential to be effective in saving gas energy), which can make the application of an energy-saving program more effective as a decision support model. [Copyright &y& Elsevier]

The basic biomechanical laws that apply to the clawed toes of animals with powerful digging abilities and the optimal bionic design of curved soil cultivating components with an analogous contour were researched in a novel way. First, the curvature and profile of the inside contour line of a field mouse’s clawed toe were analyzed. The finite element method (FEM) was then used to simulate the working process in order to study the changing characteristics of the working resistance of bionic soil-engaging surfaces and the stress field of the processed soil. A straight-line cultivating component was used for comparative analysis. In accordance with the simulation results, a series of soil cultivating components of varying design were manufactured. An indoor soil bin experiment was carried out to measure their working resistance and validate the results of the FEM analysis. The results of this research would have important values in the optimization design of cultivating components for energy and cost savings. [ABSTRACT FROM AUTHOR]

Abstract: Magnetic properties of a recently developed Fe-based amorphous alloy with a high saturation induction of 1.65T are reviewed. The increased saturation induction is fully utilized in transformers with reduced magnetic losses, physical sizes and audible noises, minimizing some of the drawbacks of amorphous metal-based transformers based on a currently available amorphous alloy. Impacts of this on the worldwide energy savings and reduction of greenhouse gas emissions are discussed. A recent effort in achieving a saturation induction beyond 1.65T in nanocrystalline alloys is mentioned. [Copyright &y& Elsevier]

Households in Europe are considered to have the largest cost-effective energy-saving potential. This large potential, however, is in the existing residential buildings, and most of these were built before 1950. If serious energy savings are to be met in the near future, it is necessary to carry out intensive renewal of these old buildings. Large investment, however, should include progressive solutions regarding usability and comfort. Also, changes to the buildings should be carried out using sound solutions without the risk of disturbing the moisture balance resulting in mould growth or deterioration. Large-scale renewal for energy saving could be carried out using the technology of custom-made prefabrication already known today. One of the key issues in future energy-saving renewal is accepting changes to the exterior façade of old buildings. [ABSTRACT FROM AUTHOR]