End-use Energy Research Articles

What is the driving mechanism for the carbon emissions in the building sector? An integrated DEMATEL-ISM model

Clarifying the critical driving factors and the driving mechanism for building carbon emissions is fundamental for carbon peak and carbon neutrality prediction. This study comprehensively identifies 23 representative factors using the literature research and questionnaire survey method. Then, by coupling the decision-making trial and evaluation laboratory (DEMATEL) method and the interpretive structural model (ISM), an integrated DEMATEL-ISM model is developed. The proposed model is further employed to quantify the causal relationships among the factors and establish a multi-level recursive structure model to determine the action mechanism of those drivers. The results show that the 11 cause factors, 12 effect factors and the three most important factors including the economic development level, building end-use energy consumption and end-use energy intensity are identified based on the calculated cause and center degree. Based on the obtained hierarchy, the 23 factors are divided into six levels, among which the population factors, the economic development, the urbanization level and the share of the tertiary sector are the root factors leading to the building carbon emissions. In comparison, policy factors are the most critical inhibiting factors. This study can not only promote the theory and model development for the driving mechanism of carbon emissions, but also help decision-makers develop scientific carbon reduction strategies.

Toward carbon neutrality in China: A national wide carbon flow tracing and the CO2 emission control strategies for CO2-intensive industries

Massive emission of CO2 as a potential driver of climate change has become a global issue presented in front of the whole human beings. Motivated by the CO2 cut-down requirement, China has aggressively undertaken restrictions aiming for peaking the carbon dioxide by 2030 and achieving carbon neutrality by 2060. However, due to the complex structures of industry and fossil fuel consumption in China, specific carbon neutrality route and the CO2 reduction potential are still open questions. To address the bottleneck of the “dual-carbon” target, quantitative carbon transfer and emission of different sectors are traced based on mass balance model. The future CO2 reduction potentials are predicted based on structural path decomposition, with consideration of energy efficiency enhancement and process innovation. Electricity generation, iron & steel industry and cement industry are identified as the top three CO2-intensive sectors, with CO2 intensity of at around 517 kg CO2/MWh, 2017 kg CO2/t CS and 843 kg CO2/t clinker, respectively. Non-fossil power is suggested to substitute coal-fired boilers to achieve decarbonization of the electricity generation industry, which is the largest energy conversion sector in China. As two dominant energy end-users, the iron & steel industry and cement industry exhibit different CO2 emission sources, requiring divergent approaches for low-carbon development. For the iron & steel industry, around 89 % direct CO2 emission comes from fossil fuel. Immediate energy efficiency enhancements are suggested, followed by process innovations such as oxy-blast furnaces, hydrogen-based reduction, and scrap-based electric arc furnaces. For the cement industry, around 66 % of direct CO2 emission comes from carbonate decomposition. The process innovation with CO2 enrich and recovery would be the most effectiveness for carbon reduction. Staged low-carbon policies of the three CO2-intensive industries are introduced at the end of this paper, which is capable of achieving 75–80 % cut down of CO2 emission intensity in China till 2060.

Investigating pathways to a net-zero emissions building sector in the European Union: what role for the energy efficiency first principle?

European Union (EU) legislation is increasingly embracing the energy efficiency first (EE1st) principle. This principle seeks to prioritise energy efficiency measures whenever these involve lower costs to society than generators, networks and other energy supply options while achieving the same outcomes. This study contributes to the quantitative evidence on the relevance of EE1st by modelling the impact of moderate to ambitious end-use energy efficiency measures on energy supply and the associated system cost under a net-zero greenhouse gas emissions constraint by 2050. These measures focus on the EU building sector and include both building retrofits (e.g. wall insulation) and efficient products (e.g. lighting). The results indicate that implementing more ambitious energy saving measures reduces the total electricity, heat and hydrogen capacities needed to achieve the net-zero target. Reducing energy use in buildings by at least 21% between 2020 and 2050 is essential to avoid excessive energy supply costs. This requires actions that go well beyond business-as-usual trends. Reductions of around 30% could be justified on the grounds of (i) high fossil fuel prices and (ii) multiple impacts (e.g. health benefits). Overall, the outcomes provide reasonable justification for the EE1st principle. To put the principle into practice, policy actions such as doubling building renovation rates and setting higher energy efficiency targets are key.

The role of public energy advising in sustainability transitions – empirical evidence from Sweden

Public energy advising is a policy measure used to provide customized energy information and advice to energy end-users. It aims at encouraging and promoting decisions leading to reduced environmental impact from energy use. While the independent function of public energy advising is unique and important, in Sweden, the role of energy advisors is changing. With new and more complex client demands as well as increasing competition from other forms of advising, there is a need to examine the shift that public energy advising is facing. The aim is to provide an overview of the activities performed by public energy advisors in Sweden and to explore the roles that they play in the transition to a sustainable energy system. Based on a qualitative analysis of 129 activity reports from Swedish municipal energy advisors, this paper shows that public energy advisors do not only play a role on an actor-level, but also on a system-level, by undertaking activities connecting the target groups to other actors in society and translating national policy to the local level. These system-level roles represent an important potential for policies aimed at accelerating the energy transition, and thus they should be encouraged and maximized.

Power Electronic Applications in Power and Energy Systems

Modern environmental policies, carbon emission reduction targets, stimulus funding for economy recovery, end-use energy efficiency, objectives for higher reliability, and service quality in energy systems are a few of the factors driving forces behind the integration of advanced control and communication technologies into energy systems [...]

On the adoption of stricter energy efficiency standards for residential air conditioners: Case study Guayaquil, Ecuador

Space cooling is the fastest-growing energy end-use in buildings worldwide, and Ecuador is no exception. Nevertheless, the last update of the Minimum Energy Performance Standards (MEPS) for air conditioners was in 2013 (EER 3.2W/W); since then, no new standards have been proposed in Ecuador. This study is the first assessment of stricter MEPS and estimation of benefits for the consumers and society of the residential sector in Guayaquil, Ecuador. The life cycle cost, payback time, net present value, electricity savings, and CO2 mitigation are the outputs from the Policy Analysis Modeling System (PAMS) methodology followed. The analysis considers future economic scenarios until 2035. Also, a new engineering approach based on linear optimization defines ACs designs in compliance with the proposed MEPS at the lowest cost. Therefore we can avoid setting less ambitious energy-efficiency targets when efficiency options are limited in the market (this is the Ecuadorian case). The analyzed MEPS are those proposed by UNEP and by the renewal program of inefficient equipment of the Ecuadorian Government. Our estimates show that AC demand can reach 17.3% of the total residential electricity demand in the business-as-usual scenario and 21.4% in the high economic growth scenario until 2035.Furthermore, the results show a significant gap between the proposed MEPS which can be progressively bridged. The best standard from the consumer perspective is EER 4.3W/W, while from the societal perspective, it is EER 5.5W/W. Stricter MEPS can reduce AC electricity demand and energy-related emissions between 5.7% and 31%, depending on the selected scenario. Therefore, stricter MEPS for AC represents a cost-effective option to reduce energy needs and emissions from air conditioners and a concrete action to support the national energy efficiency policies and nationally determined contributions for the residential sector.

Comparison of energy-efficiency benchmarking methodologies for residential buildings

Benchmarking with defined metrics is an excellent tool to track progress and obtain the desired goals. Benchmarking end-use energy in the residential sector has been a topic of great interest among researchers in recent times. This research analyses the buildings’ energy performance based on a devised benchmarking procedure for residential buildings in the Indian city of Jaipur. Creation of benchmarking system involves collection, analysis and verification of the results obtained from a similar set of data into consideration. This study explores the relationship between the Energy Performance Index (EPI) and with other influencing factors like; Area, end-use appliances (Fridge, AC, Cooler, etc.) to ensure the contribution of each variable towards the buildings’ end-use energy consumption. In this study, information has been collected and analysed from over 2700 houses of Jaipur City. The independent and dependent variables have been identified, and a five-star benchmarking framework has been developed. There are very few studies available investigating the effectiveness of various benchmarking techniques, the domain still lacks a comparative performance study of black-box and gray-box benchmarking techniques. This study has selected two black box approaches and one gray box approach to design a benchmarking model and has compared the energy performance of sample buildings. According to the Pearson and Spearman correlation coefficients, Multiple Linear Regression (MLR) and Bayesian ranking scores are the most consistent for energy benchmarking of the residential building sector. This study proposes a novel implementation of the composite indicator (C.I.) as a platform for designing energy benchmarking tables. Finally, the study concludes with recommendations for future work to employ numerous or hybrid combinations of benchmarking methodologies that are expected to provide a more accurate depiction of the energy performance of buildings.

Developing a multi-level energy benchmarking and certification system for office buildings in a cold climate region

Energy benchmarking is an accurate tool to measure, monitor, and reduce end-use energy consumption in the building sector using comparison scenarios. Various studies have applied Bottom-Up energy consumption assessment to compare the energy performance of a group of buildings with a benchmark. The Bottom-Up method mostly relies on simulating an ideal building to develop a benchmark. However, this study has developed a Top-Down energy benchmarking methodology based on the actual energy consumption within a cluster of governmental office buildings. The method presents multi-level benchmarks to provide a detailed policy for improving the energy efficiency of buildings in the short or long-term. In an exploratory study, 26 office buildings in a cold climate region were investigated to identify the multi-level benchmarks. Four general benchmark levels were developed, including the ‘Best Practice, ‘Good Practice’, ‘Benchmark’, and ‘Poor Practice’. In addition, 15 energy efficiency classes were also introduced and applied as a base for developing the ‘Energy Performance Certificate’ method. The results indicate that the benchmark values for electricity and natural gas are 40 and 252 kWh/m2/yr, respectively, while the total energy benchmark is 292 kWh/m2/yr. According to the benchmarking results, 69% of the case studies were inefficient, 23% were labeled ‘C’, and no cases were labeled ‘A’ or ‘B’. The multi-level benchmarking system can provide quick and clear guidance for building designers, operators, and government regulation/enforcement agencies; thus, it can apply at local, regional, and international levels. These benchmark levels establish reference points for measuring and rewarding good performance, on the other hand, it recognizes poor-performance buildings and prioritizes them for energy efficiency improvement. The method can be replicated in various climates and urban scales.

A Review on the Policy, Technology and Evaluation Method of Low-Carbon Buildings and Communities

In order to address global warming, most countries in the world have established carbon neutral targets and are continuously taking action to achieve carbon neutrality. The building sector accounts for 36% of end-use energy consumption and 37% of energy-related CO2 emissions globally, so carbon mitigation in building sector is considered to be the most critical step in completing the “last mile” of global carbon neutrality. Low-carbon buildings and communities are the foundation for achieving low-carbon cities and the key transition to reach the goal of carbon neutrality. Therefore, this review aimed to: (a) provide a comprehensive review of countries’ policies on low-carbon buildings and communities and a theoretical basis for improving the corresponding laws and regulations; (b) investigate low-carbon technologies related to building and community construction and operation, as well as identify the current technology gaps; (c) provide a comprehensive overview of low-carbon buildings and communities assessment systems to analyze and evaluate the economic, technical, environmental and social benefits of current building and community energy systems; and (d) identify enablers and barriers in low-carbon buildings and communities to provide direction for future research. The results of this paper can provide comprehensive insights in to further achieving low-carbon buildings and communities.

Beyond cooking: An energy services perspective on household energy use in low and middle income countries

More than three billion people depend on solid fuels for household energy, especially in rural areas of low and lower-middle income countries (LIC/LMIC). Rural households in LIC/LMIC use energy for a wide range of purposes, including food preparation, space and water heating, insect repulsion, illumination or the preparation of goods for sale. However, in these contexts, the majority of energy research frames energy end use as “cooking”. So far, the different purposes for energy use have not received the necessary scientific attention. This research gap sidelines crucial insights required for the scientific analysis of sustainable energy transitions.Research on energy services emphasizes the multitude of purposes of energy consumption. This paper shifts the research focus towards an energy services perspective and presents results of a case study from Ethiopia. We analyse combinations of domestic energy services derived from biomass-based energy carriers and household appliances. Our study uses a mixed-methods approach to integrate qualitative interview data and quantitative data from a household survey.We show that cooking is rarely performed as an isolated domestic energy service. Instead, households usually cover several interconnected energy service needs simultaneously. Availability and utility of stoves, fireplaces and energy carriers determine how and when energy services are combined. Improved cookstoves (ICS) allow for fewer energy service combinations than less efficient appliances but reduce energy consumption.Our study underlines that an energy services perspective is indispensable to understand domestic energy use and answers the question what energy is actually used for. A better grasp of the purposes of energy use supports the development of adapted solutions and advances research into sustainable energy transitions.

Investigating energy efficiency and solar energy in Saudi mosques to achieve zero energy or zero bill

Energy is essential to achieve thermal comfort; however, energy consumption leads to environmental degradation. This study analyzed the energy consumption of two masjids in the Kingdom of Saudi Arabia (KSA) and identified opportunities for rationalizing energy consumption. A photovoltaic (PV) system was used to ensure that the conditions of nearly zero bill building (nZBB) or nearly zero energy building (nZEB) were fulfilled. The energy use intensities of the Al-Jamil and Al-Omar masjids were 111 kWh/m2 and 121 kWh/m2, respectively. The average electricity consumption per worshiper for the Al-Omar masjid was 1.35 kWh/prayer and that for the Al-Jamil masjid was 1.03 kWh/prayer. The end-use energy was the highest for cooling, accounting for 72–74 % of the total consumption; lighting accounted for 11–12 % of the total consumption at the two masjids. Approximately 60 % of the air-conditioning (AC) energy load was saved by improving the envelope; the electricity requirement for ACs increased by up to 30 % as the ambient temperature increased from 32 °C to 46 °C. Changing the set-point temperature from 20 °C to 27 °C afforded electrical energy savings of approximately 27 % for a summer day. The environmental benefits of using solar energy were also identified.

Collective self-consumption for energy communities in ireland: a blockchain based application

Energy community (EC) presents a pivotal role in engaging energy end-users to reach the decarbonisation target of the energy sector. Collective self-consumption (CSC) is one of the key approaches to empowering end users in EC to boost sharing of local generations. Regulatory frameworks of European Union (EU) member states provide an economic savings model to remunerate shared energy within EC. This paper presents the key elements in the regulatory arrangements concerned with economic savings for shared energy under the CSC mechanism. Furthermore, the paper investigates the possibilities of a real-life EC in Ireland participating in a collective self-consumption scheme. A blockchain-enabled platform has been developed for implementing real-life energy matching in EC to assess the technological, economic and environmental impact of CSC managed by a community energy management platform. Results show the significance of the time dimension in the energy matching algorithm, which affects local energy consumption and, subsequently, the economic savings of EC members.

Solar Power Prediction Using Dual Stream CNN-LSTM Architecture.

The integration of solar energy with a power system brings great economic and environmental benefits. However, the high penetration of solar power is challenging due to the operation and planning of the existing power system owing to the intermittence and randomicity of solar power generation. Achieving accurate predictions for power generation is important to provide high-quality electric energy for end-users. Therefore, in this paper, we introduce a deep learning-based dual-stream convolutional neural network (CNN) and long short-term nemory (LSTM) network followed by a self-attention mechanism network (DSCLANet). Here, CNN is used to learn spatial patterns and LSTM is incorporated for temporal feature extraction. The output spatial and temporal feature vectors are then fused, followed by a self-attention mechanism to select optimal features for further processing. Finally, fully connected layers are incorporated for short-term solar power prediction. The performance of DSCLANet is evaluated on DKASC Alice Spring solar datasets, and it reduces the error rate up to 0.0136 MSE, 0.0304 MAE, and 0.0458 RMSE compared to recent state-of-the-art methods.

Efficient Scheduling of Home Energy Management Controller (HEMC) Using Heuristic Optimization Techniques

The main problem for both the utility companies and the end-used is to efficiently schedule the home appliances using energy management to optimize energy consumption. The microgrid, macro grid, and Smart Grid (SG) are state-of-the-art technology that is user and environment-friendly, reliable, flexible, and controllable. Both utility companies and end-users are interested in effectively utilizing different heuristic optimization techniques to address demand-supply management efficiently based on consumption patterns. Similarly, the end-user has a greater concern with the electricity bills, how to minimize electricity bills, and how to reduce the Peak to Average Ratio (PAR). The Home Energy Management Controller (HEMC) is integrated into the smart grid, by providing many benefits to the end-user as well to the utility. In this research paper, we design an efficient HEMC system by using different heuristic optimization techniques such as Genetic Algorithm (GA), Binary Particle Swarm Optimization (BPSO), and Wind Driven Optimization (WDO), to address the problem stated above. We consider a typical home, to have a large number of appliances and an on-site renewable energy generation and storage system. As a key contribution, here we focus on incentive-based programs such as Demand Response (DR) and Time of Use (ToU) pricing schemes which restrict the end-user energy consumption during peak demands. From the results figures, it is clear that our HEMC not only schedules all the appliances but also generates optimal patterns for energy consumption based on the ToU pricing scheme. As a secondary contribution, deploying an efficient ToU scheme benefits the end-user by paying minimum electricity bills, while considering user comfort, at the same time benefiting utilities by reducing the peak demand. From the graphs, it is clear that HEMC using GA shows better results than WDO and BPSO, in energy consumption and electricity cost, while BPSO is more prominent than WDO and GA by calculating PAR.

Understanding the role of digitalization and social media on energy citizenship.

The digitalisation of the energy domain can bring forth numerous aspects of the energy transition that can boost the emergence of energy citizenship, information sharing, and improved decision-making processes. However, this is premised on citizens being able to make sense of (digital) information. Hence, this paper proposes a link between energy informatics and energy citizenship via energy literacy, considering the cognitive and affective aspects of energy literacy and their relation to behaviour and action. By doing so, this paper aims to understand how the use of energy-related information and social media within five different case studies from the GRETA project can impel energy citizenship. This paper approaches this rationale through different means: (a) structured interviews to understand how citizens understand and make use of energy information within the case studies; (b) topic modelling on the content of those interviews to identify common factors that might spur on hinder behaviour change towards energy citizenship; and (c) social media content analysis to identify key energy-related topics of discussions among citizens around the globe and assess the role of social media as a tool for energy citizenship. As a result, this paper identified some key takeaways to improve the delivery of energy-related information to energy citizens for enhanced energy citizenship. These takeaways allow to conclude that it is fundamental to surpass the formal boundaries of techno-economic constructs and start addressing qualitative/subjective constructs (e.g., emotions, affections, and feelings) to foster energy citizenship. Also, these takeaways could be translated into social mechanism principles in the design of frontend energy-related digital platforms for improved end-user interactions and energy citizenship. Finally, this paper recognised the need to incentivise energy citizens to use social media for consuming energy-related information, and the need to formulate coordinated and coherent response strategies for disseminating energy-related information.

Использование методов планирования в повышении энергетической эффективности экономики Российской Федерации

The importance of careful elaboration of state and regional policy measures to attract and protect investments in measures to improve the energy efficiency of the economy of the Russian Federation, primarily from the banking sector and private investment in the ongoing activities, is revealed. At the same time, public policy measures should ensure the protection of investments with guaranteed payback. Efficient use of energy resources is considered as the most important factor in ensuring sustainable growth of the real sector of the economy, the development of most sectors of the fuel and energy, industry, transport, housing and communal services. That is why the new Energy Saving and Energy Efficiency Improvement Plan should be closely linked to all current Economic Development Strategies. It is shown that only at the state level as a whole, with the participation of financial specialists and technical experts of all interested parties, it is possible to develop and achieve results and balance measures to improve the efficiency of energy resources use both at the federal and regional levels, as well as by sectors of the economy and end users of energy of all levels and forms of ownership.

Research on Technology Foresight of Terminal Energy Consumption Based on Delphi Survey

In view of China's "carbon peak, carbon neutral" strategy, especially the important point of reaching the carbon peak by 2035 and achieving socialist modernisation, it is important to select a number of priority end-use energy consumption technology topics to promote the company's technological innovation. Based on the results of the two rounds of the Delphi survey, eight end-use energy consumption technologies with a "dual carbon" focus should be prioritised, namely: virtual power plant technology, electric vehicle technology, impact assessment and costing of carbon emissions and reduction, and carbon dioxide capture and storage technology. The results of the Delphi survey show that R&D investment, policy mechanisms and market viability are the main constraints to the completion of these technologies. In response to these constraints, relevant recommendations are made in terms of funding input, institutional development and market development.

Sustainable Building Optimization Model for Early-Stage Design

Buildings represent the largest potential for carbon reduction worldwide. This highlights the need for a simulation and optimization method for energy management. The early design stage of buildings represents an important phase in which choices can be made to optimize design parameters. These parameters can focus on multiple areas, including energy and thermal comfort. This paper introduces the optimization of early-stage sustainable building design considering end-user energy consumption. It proposes an optimization model that integrates multiple layers, which consist of a parametric energy simulation, artificial neural network, and genetic algorithm. The proposed optimization model considers a single objective function to obtain the optimal design. The targeted goal is to obtain minimal energy consumption for residential buildings during the early design stages. Key design parameters of the building were identified for optimization and feasible ranges for them were obtained using genetic algorithms. Finally, the results of this paper include the identification of the optimal building design for the thermal comfort analysis and optimal energy performance. The model was applied to a case study in Egypt and the results showed that using the developed optimization model can lead to a 25% reduction in energy consumption.

Peer-to-peer energy communities: regulatory barriers in the EU context

The effects of climate change are already impacting people’s quality of life worldwide. Evidence highlights the urgency in action to counteract this on-going process. Europe aims at fostering the green transition becoming climate neutral by 2050. The envisioned pathway encompasses an overhaul of the energy system including an increase in renewable energy production and end-user energy efficiency. The EU further recognizes the fundamental role of citizens and communities in addressing an effective transition. Within this framework, energy communities (EC) and peer-to-peer (P2P) energy trading are emerging as new opportunities for boosting green technologies in renewable energy and the smart grid sector, and for rising citizens’ awareness of the theme. However, the implementation of P2P ECs in Europe entails complex legal challenges that cannot be solved only through sector-specific regulation. This open letter critically presents the experience gained in the H2020 NRG2peers project about the knowledge advancement in the regulatory context of the project pilot sites. These are located in four EU ecosystems (from innovators to laggards) that are: the Netherlands, Spain, Slovenia, and Italy. Each EC involved in the NRG2peers project is thus facing different challenges related to its specific socio-economic condition and energy market framework. These barriers need to be overcome and new tools will be delivered during the NRG2peers project. Moving from the lessons learnt at the pilot sites, both roadmaps at the regulatory level and an advisory app are under development to support the uptake of the next generation of European peer-to-peer Energy Communities.

Waste heat recovery solution based on a heat pipe heat exchanger for the aluminium die casting industry

An analysis of the end use of energy in the EU reveals that industry is one of the three dominant categories, which accounts for 26.1% of the final end use of energy. In the case of the aluminium industry, approximately 70% of energy consumption is due to heat and thermal processes, highlighting a vast potential for waste heat recovery technologies. Within the aluminium die casting industry, liquid aluminium is cast, formed, cooled, and further processed within a thermal heat process, which includes three sub-processes: solubilising, quenching, and ageing. In the case presented, a thermal heat process is the second most energy intensive process within the factory, and the ageing heat treatment furnace accounts for 15% of the thermal heat process. The thermal heat treatment generates a significant amount of waste heat. The recovery of that waste heat, with minimal risk of cross contamination between streams and reduced chance of equipment failure, has been achieved via the use of a heat pipe heat exchanger (HPHE). The HPHE has been designed, manufactured, and installed in the solution furnace exhaust stack. The HPHE was designed to recover up to 88.6 kW in steady state operating conditions at 400 °C. The return on investment has been evaluated at 35 months with an expected CO2 emissions reduction of 86 tCO2/year when best engineering practices are applied. Furthermore, a theoretical modelling tool to predict the thermal performance of the HPHE was developed and validated within a ±20% deviation from the experimental results. This paper further presents the development of the theoretical model to allow a characterisation of HPHE technology and will act as a guideline for the design of HPHEs within the aluminium industry.