Energy Efficiency Measures Research Articles

Energy efficiency strategies for Brazilian social housing considering a life cycle perspective: Optimisation between thermal autonomy, energy consumption and costs

This study aims to establish optimal cases for energy-efficient social housing projects in Brazil, considering a life cycle cost-benefit analysis. Energy efficiency measures for the building envelope were evaluated in representative single-family and multifamily typology projects for the lower-income sector, considering thermal autonomy, energy consumption and cost indicators. The measures estimated in terms of macrocomponents allowed for comparative evaluation and association with costs. Cases were simulated in EnergyPlus to obtain the building’s expected operational consumption. With the macrocomponents and simulation data, Python routines were used to compute results for each proposed combination. Optimal cases that present high thermal performance in the national standard (NBR 15575) with cost-effectiveness, offering guidelines for projects in the 8 Brazilian bioclimatic zones, were established. Results presented in more detail for bioclimatic zone 8 showed optimal cases, with the increase in the percentage of hours of thermal autonomy reaching 65% to 71%, whereas that of a typical building was 30%, while life cycle cost related to the envelope showed reductions of up to 22%, even with higher initial costs. This study served as a basis for the new Brazilian policy proposed by the National Housing Office (SNH) to develop new social housing projects.

Simulating households' energy transition in Amsterdam: An agent-based modeling approach

Energy efficiency measures and renewable energy are crucial to achieving climate targets and Sustainable Development Goals. Amsterdam is actively working toward these objectives by setting a carbon emissions reduction target and related policies. This study explores how homeowners' energy efficiency decisions contribute to Amsterdam's 2030 carbon emissions goal, using agent-based modeling and spatial microsimulation. We utilize spatial microsimulation to expand the data from the 2021 Dutch Housing Survey, while this generated data is then input into the agent-based model. The key finding stresses the significance of neighborhood-level analysis in energy transition planning due to the importance of contextual differences vis-à-vis energy efficiency decisions. The study also underscores tenants' game-changing role in achieving the target. The model developed for this study can be adapted and used for other places. Based on the insights from the model output, the study proposes policy recommendations that could be a useful addition to the current policy schemes in Amsterdam and similar cities.

Energy-efficient quantum non-demolition measurement with a spin-photon interface

Spin-photon interfaces (SPIs) are key devices of quantum technologies, aimed at coherently transferring quantum information between spin qubits and propagating pulses of polarized light. We study the potential of a SPI for quantum non demolition (QND) measurements of a spin state. After being initialized and scattered by the SPI, the state of a light pulse depends on the spin state. It thus plays the role of a pointer state, information being encoded in the light's temporal and polarization degrees of freedom. Building on the fully Hamiltonian resolution of the spin-light dynamics, we show that quantum superpositions of zero and single photon states outperform coherent pulses of light, producing pointer states which are more distinguishable with the same photon budget. The energetic advantage provided by quantum pulses over coherent ones is maintained when information on the spin state is extracted at the classical level by performing projective measurements on the light pulses. The proposed schemes are robust against imperfections in state of the art semi-conducting devices.

Guest Pro-environmental Behavior Towards the Implementation of Energy Efficiency through Smart Key Technology in Capsule Hotel

The purpose of this study was to determine guest pro-environmental behavior on the application of energy efficiency in capsule hotels with case studies in Bobobox Indonesia and Digital Airport Hotel. The method used in this research is qualitative analysis. The samples used were two capsule hotel management informants in Indonesia, namely Bobobox Indonesia and Digital Airport Hotel. The method used is purposive sampling. Data collection techniques in this study were carried out by online interviews through Zoom meetings and observations. Based on the results of data analysis, it can be concluded that the implementation of energy efficiency through smart key technology in capsule hotel improves the pro-environmental behavior of the guests. It can be observed through the willingness of guests to use the smart key technology implemented by the company. This study contributes to the field by exploring the impact of energy-efficient measures, particularly through the implementation of smart key technology, on guest pro-environmental behavior in the hospitality industry. The findings offer valuable insights for both businesses aiming to enhance sustainability in accommodations and travelers seeking to make eco-conscious choices while on the move.

Energy Demand Modeling for the Transition of a Coal-Dependent City to a Low-Carbon City: The Case of Ulaanbaatar City

Cities have committed to reducing greenhouse gas emissions and promoting renewable energy. However, many cities continue to rely on fossil fuels, while renewable energy sources are not used or are unable to meet the demand that fossil fuels provide. Depending on the geographic location, climate, and resources, cities must find their own path to energy sustainability. The city of Ulaanbaatar is one of the coal-dependent cities, its electricity and heat consumption mainly coming from coal. In this study, the future final energy demand of a coal-dependent city is identified and analyzed to make it a low-carbon city. Long-term energy demand projections for Ulaanbaatar to 2050 are conducted using the model for analysis of energy demand (MAED) model. Four scenarios are developed based on the existing local and national policies in the socio-economic and energy sectors, as well as more ambitious policy and technology measures recommended by various studies in the MAED_D model. The final energy demand is calculated to be 548, 460, 334, and 264 PJ in 2050 for BAU, REF, NDC, and RM scenarios, respectively, compared to 135 PJ in 2020. The results show that the high penetration of electricity and renewable energy, energy efficiency measures, and energy intensity reduction in all sectors can significantly reduce the future energy demand and help the transition towards a low-carbon city.

Comprehensive Review and Analysis of Glazing Systems towards Nearly Zero-Energy Buildings: Energy Performance, Thermal Comfort, Cost-Effectiveness, and Environmental Impact Perspectives

The global interest in nearly zero-energy buildings (NZEBs) has led to their establishment as mandatory building objectives in Europe for all new constructions starting in 2021. The principles outlined in the Energy Performance of Building Directive (EPBD) emphasize the significance of reducing energy demand through various energy efficiency measures to achieve NZEB status. Among these measures, the utilization of high-performance glazing systems plays a crucial role in ensuring natural light, ventilation, favorable solar gain, aesthetics, and positive psychological effects in buildings, while maintaining high energy performance and thermal comfort without burdening the budget or harming the environment. The use of increasingly larger glazing areas makes this topic of great relevance. Nevertheless, numerous studies frequently overlook certain crucial aspects of glazing systems in their assessments. This review study aims to assess different glazing solutions based on four critical perspectives called “EThCE”: Energy performance, thermal comfort, cost-effectiveness, and environmental impact, considering their interrelationships. Furthermore, the importance of adopting a comprehensive approach for selecting the optimal glazing solution for NZEBs is discussed. Additionally, the relationship between glazing systems and climate change is taken into account. Ultimately, the authors propose a comprehensive approach, including all the influential factors, to assist designers and homeowners in making informed decisions regarding glazing system selection for new NZEBs or NZEB retrofits in different situations.

A holistic digital workflow methodology to shifting towards net zero energy urban residential buildings in a semi-arid climate

Given the looming threats of climate change and the rapid worldwide urbanization, it is a necessity to prioritize the transition towards a carbon-free built environment. This research study provides a holistic digital methodology for parametric design of urban residential buildings with regard to the Mediterranean semi-arid climate zone of Morocco in the early design phase. The morphological parameters of the urban residential buildings, namely the buildings’ typology, the distance between buildings, the urban grid’s orientation, and the window-to-wall ratio, are evaluated in order to identify the key combinations of passive and active solar design strategies that determine the high energy performing configurations, based on the introduced Energy Performance Index (EPI), which is the ratio between solar BIPV production to maximum available installed BIPV capacity and the normalized thermal energy needs. Through an automated processing of 2187 iterations via Grasshopper, we simulate daylight autonomy, indoor thermal comfort and solar rooftop photovoltaic and building integrated photovoltaic (BIPV) energy potential. Then, we analyze the conflicting objectives of energy efficiency measures, active solar design strategies, and indoor visual comfort in the decision-making process that supports our goal of getting closer to net zero urban residential buildings. The digital workflow showed interesting trends in reaching a balanced equilibrium between performance metrics influenced by the contrasting impact of solar exposure on indoor daylight autonomy and thermal energy demand. Furthermore, the study's findings indicate that it is possible to achieve an annual load match exceeding 66,56 % while simultaneously ensuring an acceptable visual indoor comfort (sDA higher than 0.4). The findings also highlight the important role of the BIPV system in shifting towards the net zero energy goal, by contributing up to 30 % of the overall solar energy output and covering up to 20 % of the yearly self-consumption. Moreover, the energy balance evaluation on an hourly basis indicates that BIPV system notably enhances the daily load cover factor by up to 5.5 %, particularly in the case of slab SN typology, throughout the different seasons.Graphical representations of the yearly, monthly and hourly load matches and the hourly energy balance of the best performing configurations provide a thorough understanding of the potential evolution of the urban energy system over time as a result of the gradual integration of active solar electricity production.

Measuring Inequality Using Geospatial Data

Abstract The main challenge in studying inequality is limited data availability, which is particularly problematic in developing countries. This study constructs a measure of light-based geospatial income inequality (LGII) for 234 countries/territories from 1992 to 2013 using satellite data on night-lights and gridded population data. Key methodological innovations include the use of varying levels of data aggregation, and a calibration of the lights–prosperity relationship to match traditional inequality measures based on income data. The new LGII measure is significantly correlated with cross-country variation in income inequality. Within countries, the light-based inequality measure is also correlated with measures of energy efficiency and the quality of population data. Two applications of the data are provided in the fields of health economics and international finance. The results show that light- and income-based inequality measures lead to similar results, but the geospatial data offer a significant expansion of the number of observations.

Energy efficiency evaluation, technology gap ratio, and determinants of energy productivity change in developed and developing G20 economies: DEA super-SBM and MLI approaches

This study employed Slack-based measure (SBM), Meta-frontier analysis, and Malmquist–Luenberger index (MLI) approaches to measure energy efficiency (EE), production technology heterogeneity, and energy productivity variation and its main determinants in developed and developing G20 countries for the period 1995–2020. The study's findings are: (i) Average EE for G20 countries is 0.8577, but still has an improvement potential of 14.23 percent. (ii) Developed countries have a higher average EE than developing (0.8927 > 0.8290). Results further revealed that energy efficiency scores in Argentina, Australia, Brazil, France, Saudi Arabia, South Africa, the US, the UK, and Korea are>1. (iii) Technology gap ratio (TGR) value in developed countries is higher than in developing (0.9869 > 0.6801), indicating that developed countries have advanced energy technologies superiority. The average MLI is less than one, showing a decline in energy productivity mainly due to a decline in technical efficiency, as EC < TC. (iv) Developed G20 countries get 0.64 percent aggregate growth in energy productivity as their MLI score is 1.0064, mainly due to technological growth (TC = 1.0161). Developing G20 countries, on the other hand, witnessed a decline in their energy productivity during 1995–2020, as MLI = 0.9925 > 1, designating that, on average, there is a 0.75 % decline in MLI.

The application of EN ISO 52016-1 to assess building cost-optimal energy performance levels in Italy

In Italy, the cost-optimisation calculation procedure, based on the comparative methodology framework established by the Commission Delegated Regulation 244/2012 to derive minimum energy performance requirements of buildings, was firstly applied by means of a monthly quasi-steady-state calculation method based on EN ISO 13790. The introduction of the new EN ISO 52016-1 simplified hourly calculation method determined the possibility of testing the new assessment procedure. The aim of this work is to analyse the deviation between the monthly and hourly calculation methods in the assessment of the building energy needs for space heating and cooling and in the selection of cost-optimal solutions. The cost-optimisation analysis was hence performed on a group of buildings representative of the Italian building stock. The results of the monthly and hourly methods in terms of cost-optimal levels and packages of energy efficiency measures were then compared. Results show limited variations in the resulting global cost, while differences in the cost-optimal packages of energy efficiency measures are not negligible. A sensitivity analysis of the main economic parameters was carried out, pointing out the main influencing factors.

Impact of new energy demonstration city policy on energy efficiency: Evidence from China

This study extended the causal inference regarding the impact of the New Energy Demonstration City (NEDC) policy on energy efficiency. The effect of the NEDC policy on energy efficiency was assessed by integrating the Super Efficiency Epsilon-Based Measure (SE-EBM) model and the Propensity Score Matching Difference-in-Differences (PSM-DID) method, using panel data from 271 cities in China between 2006 and 2020. Initially, the SE-EBM model was utilized to measure energy efficiency. Subsequently, the PSM-DID model was employed to evaluate the effect of the NEDC policy on energy efficiency. The findings revealed that the NEDC policy had significantly enhanced energy efficiency in demonstration cities by approximately 4.8% compared to non-demonstration cities. To ensure the reliability of the results, we conducted five tests and confirmed that the policy effect was significant only after a lag of two periods. It was found that green technology innovation was a key channel for the NEDC policy to improve energy efficiency. This study offers valuable insights into the impact of energy transition policy on energy efficiency and lays a theoretical foundation for designing effective urban energy transition policies.

The main aspects of the energy management system implementation by higher education institutions of Ukraine

The purpose is to investigate the main components of the construction of the energy management system for compliance with the requirements of DSTU ISO 50001:2020 in Ukrainian health care institutions.&#x0D; Materials and methods: informational, retrospective, based on the study of scientific literature, internet materials – resources and own conclusions.&#x0D; Research results. The dynamics of the implementation of energy management systems by Ukrainian organizations were studied. The main components of the implementation of the energy management system are analyzed: a risk-oriented approach, the concept of PDCA, senior management develops energy policy and goals and forms a series of energy efficiency measures, the energy planning process should be based on objective and operational incoming data, the constant active participation of personnel in issues energy saving and energy saving, systematic energy audits.&#x0D; Conclusions. The developed effective energy management system in Ukrainian health care institutions will make it possible to optimize energy costs, build a reliable energy saving system, and constantly improve energy efficiency as a whole.&#x0D; Key words: energy management system, energy consumption, energy saving, energy resources, energy saving, energy efficiency.

The Interconnection between Energy Efficiency and CO2 Mitigation in the Development of Multifamily Buildings

This paper aims to analyze energy efficiency in the life cycle of multifamily buildings in Metropolitan Lima, Peru, to improve productivity, competitiveness and reduce environmental impact. Decarbonization technology has been investigated, which focuses on reducing or eliminating carbon dioxide (CO2) emissions from energy sources used by buildings, thus contributing to the fight against climate change. This study collected statistical information from real estate projects to identify the primary means of energy consumption and greenhouse gas emissions, such as carbon dioxide (CO2). The objective was to maintain an effective balance between costs, time, and quality, thus ensuring the productivity and profitability of the buildings. The research method was deductive, using a quantitative approach to analyze numerical data on energy efficiency in multifamily buildings. The applied orientation allowed linking the findings with the concrete improvement of construction and operational practices. The study is framed within a descriptive and correlational approach, allowing the identification of relationships between energy efficiency and CO2 emissions and explaining the relationship between these variables. The study design was non-experimental, as no controlled manipulations of variables were performed. A cross-cutting and forward-looking approach was adopted, analyzing the data at a single point and considering possible future effects of the energy efficiency measures implemented. As a result of the analysis, it was found that the application of energy efficiency measures allowed a 25.00% reduction in CO2 emissions. This finding highlights the relevance of energy efficiency as an effective tool to mitigate the environmental impact of multifamily buildings in the region. In conclusion, this study has shown that implementing energy efficiency practices can significantly reduce CO2 emissions in multifamily buildings in Metropolitan Lima. These results provide a solid basis for adopting sustainable measures in the development and operation of facilities, aiming towards more environmentally friendly construction and contributing to the fight against climate change.

Energy efficiency and productivity in emerging and developing Asian countries: A firm level analysis

The Asian region has experienced tremendous growth in recent years. As in therest of the world, this progress has led to significant energy consumption, which in turn is having a major environmental impact. As a result, energy efficiency strategies have become the order of the day for many industries. However, the relationship betweenproductivity and energy efficiency has hardly been studied at thefirm's level. This paper uses three measuresfor a comprehensive analysis of firm-level productivity and energy efficiency in Asian emerging and developing countries. Data from the World Bank Enterprise Surveys (WBES) from 2011 to 2016 are used for the empirical analysis. The results show that manufacturing businesses' Productivity ispositively associated with energy efficiency acrossthe region. These results are robust acrossall three energy efficiency measures, accounting for heterogeneity by countryand industry, and are consistent with Porter's hypothesis that improving environmental quality leads tohigher firm Productivity. Thus, the results support the proposition that improving energy efficiency contributes to increasing manufacturing firms' Productivity. Therefore, focusing on energy efficiency should bean integral part of policy-making for companies looking to increase output as well as to improve environmental quality.

Exploring energy efficiency barriers and drivers In the Portuguese water sector

While research, development, and implementation of energy efficiency measures in water and wastewater utilities are accelerating, there has been little research into the barriers and drivers to their adoption within the sector. This study presents the findings of a series of 11 semi-structured interviews conducted to Portuguese water and wastewater utilities. The results show the prioritization of quality-of-service subjects, such as reducing water losses and increasing the resilience of systems, over energy efficiency in this sector. Despite referring to financial barriers as important, the interviewees point out that the major barriers are the lack of human resources, lack of internal technical skills, and the bureaucratic public procurement processes. The main drivers highlighted in this study are the existence of awareness campaigns and dissemination of good practices, the existence of energy service companies, and the availability of funding, either public or specific financing programs with accessible rates. The results of this research can help define sector-oriented policies fostering the adoption of measures and strategies that help improve the energy performance and resilience of water and wastewater utilities worldwide.

Heat loss reduction and tap temperature equalization of a centralized domestic hot water system in a modernized pre-WWI residential building

Savings potentials in Domestic Hot Water (DHW) systems are very often overlooked, as these systems are designed to require as little maintenance as possible. The present work therefore focuses on the optimization of a DHW circulation system in a modernized pre-WWI multistory residential building in Vienna, Austria. To minimize the heat losses of the system and reduce the natural gas consumption for DHW production, a simple approach was chosen and implemented by installing and adjusting (i) a plug-in type timer switch and (ii) a plug-in type temperature switch to control the operation of the DHW circulation pump. In terms of piping and insulation, the DHW system was not modified whatsoever. Measurements were carried out to test the suitability and effectiveness of the selected concepts. The data obtained were evaluated in terms of reproducibility, DHW system heat losses and primary energy savings, as well as user comfort (tap temperature progression) and health and safety aspects. The results show that the implementation of a widely available and inexpensive temperature switch for controlling the DHW circulation pump led to remarkable DHW system heat loss reductions in the range of 20–30%, which corresponds to primary energy savings of 15–20%, with no negative impact on user comfort and DHW safety compliance. The share of electrical energy savings due to the reduction of the operating time of the circulation pump is negligible, as are the costs of the installed equipment of the presented energy efficiency measure.

Assessment of Subsidization Strategies for Multi-Objective Optimization of Energy Efficiency Measures for Building Renovation at District Scale

In recent years, public authorities around the world have used incentive strategies to encourage the renovation of the existing building stock to meet the set carbon neutrality targets. However, the design of the incentives typically does not consider that the subsidized energy efficiency measures should result in robust long-term improvements with respect to various objectives. Moreover, building energy retrofit analyses are commonly conducted at the individual building level rather than at urban scale, which could instead significantly accelerate the renovation rate. In this context, the current research aims to combine these different factors to support the design of building energy retrofit programs. We developed 21 subsidization strategies and their impact was evaluated on a parametric multi-objective optimization with respect to energy, economic, and environmental performance for a district located in Bolzano, Northern Italy. The optimization was performed considering a set of energy efficiency measures, pertaining to building envelope, climate change, economic scenarios, and two types of energy supplies. The results showed that (1) the impact of climate change is limited for the climate of Bolzano; (2) the type of energy supply strongly influences the economic feasibility of the retrofit investments; (3) when the investment is profitable, the optimal solutions include those measures with the largest impact on energy efficiency; and (4) subsidization strategies modify the number and composition of the Pareto solutions.

Enhancing Energy Processes and Facilities Redesign in an Anaerobic Digestion Plant for Biomethane Production

The energy revolution prioritizes efficiency, sustainability, practicality, and concreteness. Conventional energy processes remain crucial and will continue to be essential for a long time if they are based on renewable and clean sources. Biofuels, particularly biomethane, are gaining significant attention for their potential to replace fossil fuels and contribute to a greener energy landscape. This paper focuses on enhancing the energy efficiency of an anaerobic digestion plant for biomethane production. Oversizing issues in technical plants often result in excessive energy and economic costs. Therefore, this study aims to analyze plant sections that can be improved to enhance performance. An energy analysis quantifies the energy requirements for different sections and sub-sections, guiding the selection of energy interventions such as pipeline resizing, heat generator modifications, pump enhancements, and energy recovery opportunities. The methodology is applied to an existing biomethane plant, and graphical software is used for redesigning the heat generator, pumps, and pipelines. The results demonstrated that implementing energy efficiency measures improves system performance. The heat generator’s capacity was successfully reduced by 100 kW, surpassing the initial design choice. Additionally, heat recovery from the biogas compression section has enhanced the overall thermal dynamics of the system. The estimated annual methane consumption in the boiler is approximately 12,000 Nm3, resulting in an expenditure of EUR 10600. These interventions have led to substantial savings, totaling EUR 133000 for the comprehensive thermal sustenance of the entire plant.

Economics of deploying LED lamps as energy efficiency measure in the Senate building of the University of Lagos using time series analysis

The increase in energy waste from energy consuming technologies and human behavior with simultaneous sharp increases in electricity tariffs impinge negatively onto the available distributable income of every energy end-user in both public and private institutions. This paper assesses the impact of an energy management investment in a public building. The eleven-story public building in this case study is the Senate building of the University of Lagos, Nigeria. The energy baseline and economic impact of LED lamps deployment as a sustainable and advanced engineering method for achieving clean energy and cost savings are examined. The ISO50002:2014 energy audit procedure was used in accordance with the energy performance improvement in the building to assess and quantify the lighting energy management potential. The lighting energy consumption, relative humidity, and air temperature in this model were tested for co-integration to determine their relationships. The economic impact in the form of Net Present Value (NPV) was calculated for a period of 8 years at a discount rate of 15%. The overall result, compared to the baseline, indicates that energy efficient lighting does impact positively and significantly on the energy consumption and cost of energy in the building. In terms of elasticities, the regression result indicates that a 1% increase in electricity consumption attributable to lighting will lead to 0.28% increase in energy cost. The results show that the base case types of lighting have a negative NPV of $3,195.98, in contrast to the high-quality LED lamps with a positive NPV of $ 27,945.40.

Electrical design for efficiency: technical and operational measures for optimizing the use of electrical power on ships

There is currently a growing concern in the shipping industry about energy consumption and environmental impacts. According to the International Maritime Organization's (IMO) energy efficiency guidelines, today's ships must have an energy efficiency management plan to reduce the CO2 emission and other pollutants. In this article, a bibliographic review of methodologies for the optimization of energy consumption on ships is carried out, starting from the identification of sources of energy losses, to the implementation of technical and operational measures that contribute to their improvement, making a qualitative evaluation of the identified methodologies. Sources of energy losses associated with equipment and auxiliary systems are analyzed, as well as opportunities for improvement in the use of electrical energy through the implementation of intelligent energy management systems, high efficiency motors, and lighting. The technical and operational energy efficiency measures described above demonstrate the importance of their implementation from the early stages of the ship's electrical design, as well as monitoring energy consumption during its life cycle, to improve energy efficiency on board.