Energy Efficiency Requirements Research Articles

Does energy-efficiency label affect appliance price? Empirical analysis of the new national standard air conditioners in China

A new national standard (NS) for energy-efficiency labels has been released in China to improve the energy-efficiency requirements of household appliances. However, the impacts of the newly revised NS for air conditioners (ACs) on consumer preference and willingness to pay (WTP) remain unclear. Using data from a large e-commerce website in China, this study explores users’ preferences and WTP for the attributes of online stores, comments, and products pertaining to new NS ACs based on the hedonic price model (HPM), and uses the Heckman two-step estimation to correct for selection bias. The results show that the premium of the new NS energy-efficiency label estimated by the Heckman model is 6.24%, which is 23.71% lower than that estimated directly by the HPM. Online store attributes and comment attributes also affect the prices of new NS ACs. Furthermore, product attributes have effects on the prices of both new and old NS ACs, while online store attributes and comment attributes have greater effects on the old NS ACs. Finally, after the implementation of the new NS, the premium for the new NS energy-efficiency label is lower than that of the old one.

АНАЛИЗ СХЕМОТЕХНИЧЕСКИХ РЕШЕНИЙ И СПОСОБОВ ПОВЫШЕНИЯ ЭНЕРГЕТИЧЕСКОЙ ЭФФЕКТИВНОСТИ ЗАРЯДНЫХ УСТРОЙСТВ

Relevance An inductive-capacitive converter (ICC) is one of the main elements of a capacitive storage device. With the right choice of the ICC scheme in a particular device, it is possible to achieve the necessary energy efficiency indicators of the final installation. The article sets the task of choosing the most energy-efficient design scheme of an inductive-capacitive converter for a capacitive storage device, which can be used in an electrohydroimpulse cleaning device, as well as in electric vehicle charging stations. Aim of research Conduct an analytical review of existing circuits of an inductivecapacitive current converter and choose the most energy-efficient circuit for charging a capacitive storage device. Research methods Analytical review of scientific literature. Results As a result of the analytical review of the existing circuit designs of the inductive-capacitive converter, a circuit that meets the necessary energy efficiency requirements has been selected.

Lipolytic and oxidative changes in acoustically assisted frozen fattened duck liver

The delicate structure of the fattened duck liver requires rapid freezing as quickly as possible. Acoustically assisted freezing meets both the requirement for quick freezing and energy efficiency. For the purpose of the experiment, a fattened duck liver “foie gras” was used. The degree of lipolysis (acid value) and primary (peroxide value) and secondary (2-thiobarbituric acid value) products of lipid oxidization were examined at 2 h post mortem. The oxidative changes were evaluated after conventional (CF) and acoustically assisted freezing (AAF) and at the 6-th and 12-th month of storage at -18°C. Both time storage and type of freezing affect the degree of lipolysis. The duck liver after AAF had higher degree of lipolysis at the 12-th month of storage at -18°C. The peroxide value increased almost 2 times in both fattened duck livers (CF and AAF) during the 6 months of storage at -18°C and stabilizes until the 12-th month. A conclusion was made that the acoustically assisted freezing of the fattened duck liver did not promote higher lipid oxidation compared to the conventional type of freezing.

PROSPECTS FOR THE DEVELOPMENT OF POWER SUPPLY SYSTEMS FOR AGRICULTURAL FACILITIES BASED ON DISTRIBUTED ENERGY SUPPLY

Modern trends in the development of electric distribution networks for agro-industrial facilities related to the introduction of more complex production technologies, increased consumer loads and stricter requirements for reliability and energy efficiency of networks are considered. In the conditions of sectoral supply restrictions and the need to replace imported components, the possibilities of implementing the advantages of distributed electric power in flexible energy supply of agro-industrial and social facilities on the basis of domestic technology and innovative methods are presented. (Research purpose) The research purpose is considering the technical support of distributed generation systems and analyzing possible problems that may arise during the integration of distributed generation sources into the electrical system of the agro-industrial complex. (Materials and methods) Used statistical data to analyze the availability of agro-industrial facilities with distributed electric power. (Results and discussion) It has been shown that the agro-industrial complex is dominated by objects that are far removed from the center of the energy system, with electrical equipment that is morally and technically outdated, which affects the reliability of power supply and the quality of electricity. It was determined that the introduction of distributed generation sources requires modernization or updating of the main electrical equipment of distribution points or substations. Alternative technical solutions have been proposed to improve the quality of electricity supplied to consumers and the reliability of power supply systems, focused on the maximum approximation of the power source to the consumer by placing distributed generation sources near the objects of the agro-industrial complex. They gave specific schemes of power supply systems, the results of technical and economic analysis and options for using traditional and renewable sources of electricity. (Conclusions) It was stated that the further development of the agro-industrial complex facilities is associated with an increase in the level of energy supply, reliability, energy efficiency and environmental friendliness of power supply systems through the introduction of modern distributed generation systems based on traditional, renewable and combined sources of electricity.

Obtaining colloidal silicon dioxide (Sio2) from quartz

Colloidal amorphous silica is a product based on micronized silicon dioxide (SiO2) powder. The product is in large demand on the market due to its outstanding adsorption properties. It is widely known as AEROSIL®. The AEROSIL® technology is based on the use of silicon tetrachloride (SiCl4) as a raw material component, which determines the cost, energy and environmental assessments of the process. One of the ways to improve these technical and economic assessments is to find solutions that eliminate the use of SiCl4 from the process of producing micronized quartz powder. As an alternative technology, we consider plasma processes for the production of nano-powders of silica according to a scheme that eliminates the need to produce SiCl4. In the proposed scheme, amorphous silicon dioxide is produced using a technology with direct use of a natural source of silicon – quartzite. The technology is realized by a sequence of technological operations of activation of quartzite particles and deep energy-efficient purification of quartz at the molecular level, which allows to obtain ultrafine amorphous silica of high purity. Performing technological operations at low temperatures and without energy consumption for melting materials, complete regeneration of reagents allows us to meet the requirements of cost-effectiveness, energy efficiency and environmental friendliness of production.

Next-Generation IoT Devices: Sustainable Eco-Friendly Manufacturing, Energy Harvesting, and Wireless Connectivity

This invited paper presents potential solutions for tackling some of the main underlying challenges toward developing sustainable Internet-of-things (IoT) devices with a focus on eco-friendly manufacturing, sustainable powering, and wireless connectivity for next-generation IoT devices. The diverse applications of IoT systems, such as smart cities, wearable devices, self-driving cars, and industrial automation, are driving up the number of IoT systems at an unprecedented rate. In recent years, the rapidly-increasing number of IoT devices and the diverse application-specific system requirements have resulted in a paradigm shift in manufacturing processes, powering methods, and wireless connectivity solutions. The traditional cloud-centering IoT systems are moving toward distributed intelligence schemes that impose strict requirements on IoT devices, e.g., operating range, latency, and reliability. In this article, we provide an overview of hardware-related research trends and application use cases of emerging IoT systems and highlight the enabling technologies of next-generation IoT. We review eco-friendly manufacturing for next-generation IoT devices, present alternative biodegradable and eco-friendly options to replace existing materials, and discuss sustainable powering IoT devices by exploiting energy harvesting and wireless power transfer. Finally, we present (ultra-)low-power wireless connectivity solutions that meet the stringent energy efficiency and data rate requirements of future IoT systems that are compatible with a batteryless operation.

Organization of major repairs of apartment buildings with energy-saving technologies

In today’s Russia, development of new regulatory requirements related to major repairs of apartment buildings is much less needed than harmonization and enforcement of existing regulations. In order to meet the energy efficiency requirements for apartment buildings after major repairs, it is necessary to develop a set of energy-saving measures that will increase the energy efficiency of buildings and the comfort of living. The main particularities of the organization of repair and construction during major repairs include requirements for modeling the order of different types of work at each facility under financial and time constraints. This said, we can conclude that it is necessary to determine the optimal sequence of application of energy-saving technologies during repair and construction within the major repairs of apartment buildings and the effectiveness of the applied technology.

Theoretical essentials for designing viscous liquid pumping systems in the conditions of the Arctic region

The purpose is the creation of a scientifically based solution for the design of hermetic electromechanical converters adapted to existing pipelines, as well as those under construction and development. These pipelines meet the energy efficiency requirements and operate in the conditions of the Arctic region. Methods: methods of mathematical analysis, numerical methods, and methods of mathematical programming were used as the main mathematical means. The CFD design package of Ansys Maxwell was used. Research results: we showed that an increase of the efficiency of the system of technological transportation of petroleum products at low temperatures is possible through the use of electromechanical devices that combine the functions of heating and pumping the working liquid. We solved the field problem based on the analytical calculations carried out by a computer. This allowed us to determine the distribution of eddy current density in the structural elements of these devices responsible for creating pressure and heating the pumped petroleum products. The importance of the electrical parameters of the secondary windings has been confirmed numerically and experimentally. The hydraulic characteristics, mechanical losses, volumetric losses and efficiency are determined. Taking into account the outcomes of theoretical studies the experimental sample of the sealed electromechanical converter with the specified physical and chemical characteristics was created at Emperor Alexander I St. Petersburg State Transport University. Practical relevance: the obtained analytical formulas can be used at the development of the systems for pumping viscous liquids at low temperatures using the sealed electromechanical converters which helps to reduce the installed power of energy equipment without degrading the values of technological indicators.

NOx reduction system selection and energy efficiency impact evaluation for ships sailing in restricted areas

The worldwide shipping provides 90 percent of the goods carriage and in the last 20 years their absolute volume is constantly increasing. However, carriers need to maintain service levels and reduce exploitation costs, and at the same time must ensure higher sustainability in all operations. The growth in number of ships in service inevitably leads to much more harmful emissions released by vessels in to the atmosphere. In the same time, more stringent environmental requirements and laws continue to regulate the maritime transport sector. Progress was made by International Maritime Organization (IMO) towards the ambition on reduction of greenhouse gas (GHG) emissions from ships. That is why IMO based International Convention for the Prevention of Pollution from Ships (MARPOL Convention) and its regulations continuously sets higher thresholds for environment protection expressed by Nitrous Oxides (NOx), Sulphur Oxides (SOx) and Carbone Dioxides (CO2) limitations. The new higher ecological requirements put on the table new technical and economic challenges for the shipowners and ship designers.In the current paper Selective Catalytic Reduction (SCR) and Exhaust Gas Bypass (EGR) NOx emissions reduction systems and their affect on the fuel consumption are under consideration. The application of each system depends on the ship’s type, installed propulsion system and its main engines and operational modes.The numerical study is carried based on 31800 DWT vessel for bulk loads, operating in restricted areas of the Great Lakes of North America. In the course of the research the fulfilment of the following objectives are being leaned: the ship must be capable for operation in Nitrogen Emission Control Areas (NECA’s), as well as its Energy Efficiency Design Index (EEDI) must be in compliance with Required Energy Efficiency Design Index (REEDI) Phase 3 coming in force in 2025.

To PiM or Not to PiM

As artificial intelligence becomes a pervasive tool for the billions of IoT (Internet of things) devices at the edge, the data movement bottleneck imposes severe limitations on the performance and autonomy of these systems. PiM (processing-in-memory) is emerging as a way of mitigating the data movement bottleneck while satisfying the stringent performance, energy efficiency, and accuracy requirements of edge imaging applications that rely on CNNs (convolutional neural networks).

Analysis of the compliance of windows with up to day energy efficiency requirements

Due to the consequences of the energy and environmental crises, reducing energy consumption in buildings is an urgent task, both globally and nationally. It is this goal that causes a constant increase in the requirements for resistance to heat transfer of the external enclosing structures of buildings in climatic conditions, where the design temperature of the outside air is at the level of -20ºС. Increasing the resistance of non-transparent enclosing structures is achieved by available means that allow guaranteed achievement of the designated resistance to heat transfer. Increasing the heat transfer resistance of transparent (or translucent) enclosing structures has limitations that limit the maximum values. The analysis of window designs that are offered on the construction market of Ukraine in the context of the requirements of DBN V.2.6.31-2021 "Thermal insulation and energy efficiency of buildings" was carried out. To increase the resistance to heat transfer of windows, the manufacturer has (today) three constructive means - an increase in the number of chambers, the use of selective coatings and filling the chambers with an inert gas argon. It should also be taken into account that the production of windows is a multicriteria task, in which the achievement of a certain level of resistance to heat transfer is one of the factors among others, no less important. The results of the analysis show that the fulfillment of the requirement Rqmin≥0.9 m2•ºС/W for the first temperature zone of Ukraine requires the use of all technical means available from manufacturers. A sample of eighty-two window designs that are actually offered on the Ukrainian construction market was analyzed. Compliance with the requirements for the second temperature zone was achieved for forty-three percent of window designs. Compliance with the requirements for the first temperature zone was achieved for seventeen percent of window designs. The complexity and increased cost of such structures may necessitate additional control measures at the completion of construction and during the operation of buildings.

COMPREHENSIVE METHOD OF ENERGY-EFFICIENT WORKLOAD PROCESSING IN THE INFORMATION AND COMMUNICATION NETWORK

Background. Peculiarities of the workload in a modern information and communication network (ICN) determine specific requirements for energy efficiency, performance and availability of its processing system. Existing approaches to increase energy efficiency and performance of workload processing do not take into account the possibility of dynamic changes in ICN workload arrival rate and individual energy consumption characteristics of computing nodes of the system.
 Objective. The purpose of the paper is to increase the energy efficiency and performance of ICN workload processing while meeting the requirements for the availability of the processing system, taking into account dynamic changes in the input workload arrival rate and the individual characteristics of the computing nodes’ energy consumption.
 Methods. A mathematical model of the workload processing system was built using the queueing theory methods, and an ontological model of this system was built using intelligent data analysis methods, which made it possible to quantitatively and qualitatively describe the complex relationships between system parameters and workload processing efficiency indicators. On the basis of the built models, a comprehensive method of energy-efficient workload processing was proposed, which differs from the known ones by the use of individual energy consumption models of computing nodes, combining the advantages of horizontal scaling and energy-efficient scheduling taking into account dynamic changes in workload arrival rate.
 Results. The efficiency of ICN workload processing is increased by 15.722% according to the efficiency criterion, which includes energy efficiency and performance indicators, compared to the known energy-efficient Backfill approach while meeting the requirements for the availability of the processing system.
 Conclusions. The energy efficiency, performance and availability of the ICN workload processing system can be improved by combining horizontal scaling and energy-efficient scheduling approaches using individual energy consumption models of computing nodes and taking into account dynamic changes in the input workload arrival rate.

Improving concurrency and memory usage in distributed operating systems for lightweight manycores via cooperative time-sharing lightweight tasks

Lightweight manycore processors arise to reconcile performance, energy efficiency, and scalability requirements on a single chip. Operating Systems (OSes) for these processors feature a distributed design, where isolated OS instances cooperate to mitigate programmability and portability issues coming from their architectural intricacies. Currently, OS services often resort to traditional execution flow abstractions (processes or threads) to implement small, periodic, or asynchronous functionalities. Although these abstractions considerably simplify the system design, they have a non-negotiable impact on the limited on-chip memories. Due to the memory restrictions, we argue that OS-level abstractions can be reshaped to reduce the OS memory footprint without introducing considerable overhead. In this context, we propose a complementary OS-level execution engine that supports cooperative time-sharing lightweight tasks that share a unique execution stack and features task synchronization via control flow and dependency graphs. This solution is orthogonal to the underlying execution support and provides numerous OS-level execution flows with reduced memory consumption. We implemented our engine in a distributed OS and executed experiments on a lightweight manycore. Our results show that it has the following advantages when compared to the classical thread abstraction: (i) it provides 63.2× more execution flows per MB of memory; (ii) it features less overhead to manage execution flows and system calls; (iii) it improves core utilization; and (iv) it exhibits competitive results on real-world applications.

Numerical analysis of energy recovery system for turbocharged internal combustion engines via a parallel compounding turbine

Increasing energy efficiency requirements mandatory ask for optimizing energy utilization in many devices, which include internal combustion engines. One of the most investigated subjects is the energy recovery from the exhaust, such as turbo-compound systems, which usually consist in a secondary turbine located afterward the turbocharger. Here an alternative arrangement is proposed and analysed via a numerical model. The recovery turbine works in parallel to the main turbine and uses the gasses which would be otherwise wasted through the waste-gate valve, once the set-point boost pressure is reached. The reference case analysed is a 12.4L turbocharged diesel engine, commonly used in marine, road and light railroad applications, with a nominal power of 380kW. The results showed that an overall 8% of power can be gained, without nor increasing the fuel mass flow rate, neither requiring significant modifications to the baseline engine. Moreover, in the case of the recovery system failure, the operation of the engine is not affected, thus resulting in no engine availability reduction. This work also shows a feasible way to convert the mechanical energy delivered by the recovery turbine into electrical energy, by making use of a high-speed electrical generator.

Optimization of biogas-reforming conditions considering carbon formation, hydrogen production, and energy efficiencies

Hydrogen production from biogas requires energy efficiency. This study systemically compared pure biogas reforming, CO2-free biogas steam reforming, and biogas steam reforming. A comprehensive evaluation combining thermodynamic analysis, energy efficiency evaluation, and experimental validation was performed to compare the reaction types. Biogas steam reforming is the most attractive reforming reaction because it has the lowest SEC. In addition, the main parameters for the reaction conditions were investigated to optimize hydrogen production from biogas. The optimal conditions for the biogas steam reforming were determined as 750 °C and an H2O/CH4 ratio of 1.5. Finally, the previously developed Ni–MgO–CeZrO2 catalyst was tested under the optimized reaction conditions. Consequently, the catalyst showed high catalytic performance and was maintained for 30 h, even at a high GHSV of 36 000 h−1. This result implies that the optimized reaction condition derived by comparing the various indicators such as conversion of reactants, yield of products, energy consumption, and thermal efficiency is suitable for hydrogen production from biogas.

Blast enhanced façade design by means of an optimal balance between security and sustainability

The major objective of this paper is to show that glazed curtain wall has a surprising potential for blast enhancement. However, often this potential is partially lost because of inaccurate and only presumed safe side approach. Indeed, in curtain wall it is much important to assess properly the beneficial effect of the deformable supports, framing and possibly brackets, on the glazing response under blast wave effects. Only in this way a true balanced design approach can be carried out and the protective requirement can be integrated into the façade design by preserving the architectural requirements, comfort, classical energy efficiency requirements and novel demand for sustainability. On the other side the large variability of materials and component behaviour under nonlinear range and the uncertainties related to the blast threat recommend a flexible calculation tool, which must be coupled with a sensitivity analysis on the most relevant inputs. For this reason, a Multi Degree of Freedom approach shows several advantages with respect to the Explicit Dynamic Finite Element Analysis, considering also the large number of geometry, component design and blast load variations are existing in a typical application of the protection on a high rise building. The impact of the calculation method is demonstrated by means of a comparative exercise and by means of real case applications.

The impact of building energy codes evolution on the residential thermal demand

The building stock decarbonization by 2050 requires the implementation of an energy transition strategy. Building energy codes must be considered to minimize the energy consumption of the residential sector. This paper aims to evaluate the evolution of the building energy codes of Spain based on energy simulation. A quantitative assessment of the residential thermal demand according to the new energy efficiency requirements introduced in national regulations over the years was performed. Heating, cooling, and domestic hot water demands were assessed for 60 cases modeled in DesignBuilder, combining different building geometric typologies, energy codes, and climate zones. Heating presented the largest contribution to the total energy demand reaching up to 75%. The codes’ evolution led to a significant reduction in heating and a slighter decrease in cooling. The results showed an average energy demand improvement of 50% from the first regulatory release to the latest one.

A biophilic wellbeing framework for positive indoor-outdoor connections in energy-efficient Arctic buildings

This paper develops a biophilic wellbeing framework for positive indoor-outdoor connections in Arctic buildings to respond to occupants’ wellbeing and energy-efficiency requirements. Extreme cold weather and drastic photoperiods of Arctic climates could have adverse impacts on wellbeing and reduce connections with nature, i.e., identified as biophilia. Characteristics of positive relationships with extreme Arctic climatic stressors have not yet been comprehensively studied in terms of integrated wellbeing needs and energy efficiency requirements. This paper aims to articulate a fundamental wellbeing framework integrating thermal and photobiological needs with biophilic recommendations to characterize positive connections with Arctic climates for energy-efficient buildings. A scoping literature review is conducted to discuss occupants' thermal and photobiological needs in relation to biophilic recommendations and Arctic climatic conditions. As a case study, shortcomings of existing building practices in Cambridge Bay, Nunavut, Canada, are studied regarding wellbeing, indoor-outdoor connections, and energy-efficiency needs. The proposed wellbeing framework for positive indoor-outdoor connections in Arctic buildings integrates (i) thermal and (ii) photobiological indicators based on biophilic recommendations. The integrated wellbeing framework enables characterizing thermal and (photobiological) lighting adaptation scenarios responding to Arctic weather, daylighting, and photoperiods as well as energy efficiency. Intermediate spaces are also proposed as a prosing architectural solution to address the integrated wellbeing framework energy efficiency in arctic buildings. Overall, the proposed framework could help architects, building designers, and stakeholders to develop further architectural solutions for positive, energy-efficient indoor-outdoor connections for Arctic buildings and occupants.

Perspective on oxide-based three-terminal artificial synapses in physical neural networks

The physical implementation of artificial neural networks, also known as “neuromorphic engineering” as advocated by Carver Mead in the late 1980s, has become urgent because of the increasing demand on massive and unstructured data processing. complementary metal-oxide-semiconductor-based hardware suffers from high power consumption due to the von Neumann bottleneck; therefore, alternative hardware architectures and devices meeting the energy efficiency requirements are being extensively investigated for neuromorphic computing. Among the emerging neuromorphic electronics, oxide-based three-terminal artificial synapses merit the features of scalability and compatibility with the silicon technology as well as the concurrent signal transmitting-and-learning. In this Perspective, we survey four types of three-terminal artificial synapses classified by their operation mechanisms, including the oxide electrolyte-gated transistor, ion-doped oxide electrolyte-gated transistor, ferroelectric-gated transistor, and charge trapping-gated transistor. The synaptic functions mimicked by these devices are analyzed based on the tunability of the channel conductance correlated with the charge relocation and polarization in gate dielectrics. Finally, the opportunities and challenges of implementing oxide-based three-terminal artificial synapses in physical neural networks are delineated for future prospects.

Energy-Efficient Offloading Based on Efficient Cognitive Energy Management Scheme in Edge Computing Device with Energy Optimization

Edge devices and their associated computing techniques require energy efficiency to improve sustainability over time. The operating edge devices are timed to swap between different states to achieve stabilized energy efficiency. This article introduces a Cognitive Energy Management Scheme (CEMS) by considering the offloading and computational states for energy efficacy. The proposed scheme employs state learning for swapping the computing intervals for scheduling or offloading depending on the load. The edge devices are distributed at the time of scheduling and organized for first come, first serve for offloading features. In state learning, the reward is allocated for successful scheduling over offloading to prevent device exhaustion. The computation is therefore swapped for energy-reserved scheduling or offloading based on the previous computed reward. This cognitive management induces device allocation based on energy availability and computing time to prevent energy convergence. Cognitive management is limited in recent works due to non-linear swapping and missing features. The proposed CEMS addresses this issue through precise scheduling and earlier device exhaustion identification. The convergence issue is addressed using rewards assigned to post the state transitions. In the transition process, multiple device energy levels are considered. This consideration prevents early detection of exhaustive devices, unlike conventional wireless networks. The proposed scheme’s performance is compared using the metrics computing rate and time, energy efficacy, offloading ratio, and scheduling failures. The experimental results show that this scheme improves the computing rate and energy efficacy by 7.2% and 9.32%, respectively, for the varying edge devices. It reduces the offloading ratio, scheduling failures, and computing time by 14.97%, 7.27%, and 14.48%, respectively.