Domestic Buildings Research Articles

A Review of Solar-Coupled Phase Change Materials in Buildings.

Buildings use a significant percentage of the total energy consumed worldwide. Striving for energy conservation within buildings is of prime concern for researchers. Hence, scientists are aggressively exploring new energy storage and supply methods to reduce exorbitantly fluctuating energy demands and increase the share of renewable energy in building energy consumption. Solar systems that incorporate phase change materials (PCMs) for thermal storage have significant potential to serve in this context. These systems are not yet able to endure the significant energy demands, but they are being continually improved. The aim of this paper is to explore the existing solar PCM systems that are being studied or that are installed for use in indoor heating/cooling. As per the outcome of this systematic review, it has been observed that when coupled with solar thermal energy, the configuration of PCMs can either use passive or active techniques. Passive techniques are usually less efficient and more costly to implement in a building structure, resulting in active heat exchangers being widely implemented with better technical and economic results. At the same time, it has been observed that for most domestic buildings, organic PCMs with phase change temperatures of up to 42 °C and thermal conductivities of up to 0.56 W/m.K are most suitable for integration in solar thermal energy production. Hybrid systems are also commonly used for larger commercial buildings, in which the solar PCM system (SPCMS) provides a fraction of the total load. Additionally, the Stefan number is the most common technical parameter that is used to assess this performance, along with the effective thermal conductivity of the PCM after using enhancement techniques. The key economic indicator is annual savings per year, with most SPCMSs having a payback period of between 6 to 30 years. This review provides designers and researchers with key insights in terms of formulating a basis in the domain of coupling PCMs with solar thermal energy, especially within non-industrial buildings.

Study of the Combustion Characteristics and Flame Retardant Assessment of Windows in Buildings

With the increasing size and density of domestic buildings, the spread of fire from one building to adjacent ones has become a significant concern, leading to greater fire damage. The openings in these buildings have been identified as the main cause of horizontal and vertical fire diffusion, as flames repeatedly enter adjacent compartments. In this study, we focused on buildings with a high fire risk by conducting a fire risk assessment of existing structures. Commercial facilities (such as accommodation facilities) and industrial facilities (including warehouses and factories) were classified as buildings with a relatively high risk. We specifically selected PVC and AL windows, which are commonly used in buildings, to evaluate the risk of fire spread based on flame retardant assessment. However, during a fire, the exposed cross-section and quality of windows differ, making it inappropriate to evaluate their fire risk using the currently regulated flame retardant assessment test. Therefore, there is a need to establish methods and standards for flame retardant assessment tests that are specifically designed for windows.

Building Occupants, Their Behavior and the Resulting Impact on Energy Use in Campus Buildings: A Literature Review with Focus on Smart Building Systems

In the light of global climate change and the current energy crisis, it is crucial to target sustainable energy use in all sectors. Buildings still remain one of the most energy-demanding sectors. Campus buildings and higher educational buildings are important to target due to their high and increasing energy demand. This building segment also represents a research gap, as mostly office or domestic buildings have been studied previously. In the quest for thermal comfort, a key stakeholder in building energy demand is the building occupant. It is therefore crucial to promote energy-aware behaviors. The building systems are another key factor to consider. As conventional building systems are replaced with smart building systems, the entire scenario is redrawn for how building occupants interact with the building and its systems. This study argues that behavior is evolving with the smartness of building systems. By means of a semi-systematic literature review, this study presents key findings from peer-reviewed research that deal with building occupant behavior, building systems and energy use in campus buildings. The literature review was an iterative process based on six predefined research questions. Two key results are presented: a graph of reported energy-saving potentials and a conceptual framework to evaluate building occupants impact on building energy use. Furthermore, based on the identified research gaps in the selected literature, areas for future research are proposed.

Absence of evidence or evidence of absence? The microarchaeology of an ‘empty’ square enclosure of the Late Iron Age La Tène Culture

Archaeological features without macro-finds (i.e. finds visible with the naked eye) represent a common phenomenon that poses considerable methodological problems in interpretation. To tackle these problems, we present an approach based on integrating micro-archaeological methods and macro-observations to help elucidate ‘invisible’ activities or at least to exclude certain others. Specifically, we combine micromorphological and micro-debris analyses with the scarce macro-finds and their fragmentation degree to clarify whether the lack of evidence for certain activities really reflects their absence or merely bad preservation conditions. This study focuses on a Late Iron Age ‘empty’ enclosure excavated in the settlement site of Haselbach, Lower Austria. ‘Empty’ square enclosures of the La Tène Culture have been controversially interpreted as either sanctuaries, domestic buildings or burial enclosures, although these interpretations were rarely supported by any material evidence. Using a multi-proxy approach enables us to reconstruct the formation processes of the Haselbach feature as well as to rule out a range of activities, although a clear definition of its primary function was not reached. Based on our case study, we propose a research protocol that can be applied to research on similar ‘empty’ features in order to better validate their functional interpretations.

Urban Building Energy Modelling for the Renovation Wave: A Bespoke Approach Based on EPC Databases

In 2020, domestic buildings represented 27% of the energy consumption in the European Union. The EC Renovation Wave concluded that the annual renovation rate should be doubled, from 1% to 2%, over the next decade in order to meet the 2030 energy efficiency targets. Funding programs are being implemented at national and European levels to accelerate this process. These aim to prioritize large-scale interventions and the most efficient energy conservation measures by including strict performance targets as eligibility conditions. However, these programs are coordinated by local authorities, and they struggle to generate reliable energy estimates for large areas, not least predict potential savings at both aggregated and individual levels. This paper presents a bespoke energy retrofit analysis methodology based on urban building energy modelling, which is defined and calibrated with the Energy Performance Certificate Database. We apply this method to the case study Barrio das Flores. The model adopts a hybrid approach, defining and simulating representative typologies to extrapolate the results to the whole district according to each dwelling’s specific parameters. This methodology will be used to predict the potential energy savings in the study area and support the grant application for the funding renovation program.

Thermoacoustic heat pump utilizing medium/low-grade heat sources for domestic building heating

Thermoacoustic heat pumps are a promising heating technology that utilizes medium/low-grade heat to reduce reliance on electricity. This study proposes a single direct-coupled configuration for a thermoacoustic heat pump, aimed at minimizing system complexity and making it suitable for domestic applications. Numerical investigations were conducted under typical household heating conditions, including performance analysis, exergy loss evaluation, and axial distribution of key parameters. Results show that the proposed thermoacoustic heat pump achieves a heating capacity of 5.7 kW and a coefficient of performance of 1.4, with a heating temperature of 300 °C and a heat-sink temperature of 55 °C. A comparison with existing absorption heat pumps reveals favorable adaptability for large temperature lift applications. A case study conducted in Finland over an annual cycle analyzes the economic and environmental performance of the system, identifying two distinct modes based on the driving heat source: medium temperature (≥250 °C) and low temperature (<250 °C), both of which exhibit favorable heating performance. When the thermoacoustic heat pump is driven by waste heat, energy savings of 20.1 MWh/year, emission reductions of 4143 kgCO2/year, and total environmental cost savings of 1629 €/year are obtained. These results demonstrate the potential of the proposed thermoacoustic heat pump as a cost-effective and environmentally friendly option for domestic building heating using medium/low-grade heat sources.

A Comprehensive Analysis of Domestic Building Energy Efficiency Value Using VIKOR Method

"What is a room's energy efficiency?" A facility's energy efficiency is determined by comparing its power usage per square meter to the energy demand standards set for that particular type of structure in a given climate. To evaluate the floor space of each room on each floor of your building in the warmest areas, measure the area of each room precisely and then sum those measurements to get the overall floor area. The more precise the measurement, the more accurately your energy waste will be displayed as oil used per square meter. The research significance is fairly long-term energy and expense savings. Buildings that use less energy and water also have lower maintenance expenses. They also have a lower total social impact since energy-efficient structures that do not use natural gas produce fewer greenhouse gas emissions. House efficiency, in general, refers to how effectively resources like electricity and freshwater are used to operate systems and equipment placed or used in the building, as well as to provide services like heating, cooling, and lighting. Alternative factors to consider include occupant density, lighting loads, computer equipment, and additional equipment. The assessment options are open plan offices, small offices, laboratories, open computer labs, meeting rooms, and circulation. The results based on circulation show that it has the highest rank, while the laboratories have the lowest rank. The value of the dataset for building energy efficiency in the VIKOR method shows that the circulation has the top ranking.

An approach for energy management of renewable energy sources using electric vehicles and heat pumps in an integrated electricity grid system

The demand for electricity has been increasing worldwide and it is predicted that this trend will be particularly reinforced in developing countries by the gradual electrification of the transport sector and heat generation in buildings. The energy supply infrastructure required to meet the additional electricity demand should be carefully managed in light of the climate change carbon emission targets and commitments. A large proportion of the new electricity loads will be met from renewable sources. Therefore, means of power storage become vital to smooth out the intermittent nature of these energy supplies. The introduction of Electric Vehicles (EVs) could provide a viable and dynamic power storage solution through the concept of Vehicle-to-everything (V2X). This involves the storage of renewable energy (RE) in EV batteries during the charging cycle and restitution to the grid (V2G) or homes (V2H) when needed. In this context, this paper presents a methodology involving several strategies to stabilise the grid system and examines the impact of various types of EVs and heat pumps (HPs) for supplying heat in buildings. The results of this research approach show that the synergy of using V2H could reduce the carbon footprint of a typical domestic building in the United Kingdom (UK) by up to 87% and potentially recover up to 21.9 kWh/day of surplus renewable energy.

A domestic rooftop PV system: a step towards retrofitting the built environment to combat climate change in Bahrain

This article assesses the technological, economic, and environmental aspects of installing the first 7.8 kW PV installation on a rooftop of a domestic house in Bahrain for a period of 2 years (20th March 2018 to 31st March 2020). The maximum solar electricity generated was 1,228.9 kWh (August 2018), and the least was 728.16 kWh (December 2019). The maximum daily specific yield (SY) was 6.12 kWh/kWp (on 14 April 2019). The annual average daily specific yield for this domestic building was 4.13 kWh/kWp. The average performance ratio (PR) of the PV system was 73.0% in 2019. The self-sufficiency (SS) of this installation was found to vary from 15.3% to 50.7%. The average SS value in 2018 was 22.8%, while in 2019 it was 28.6%. Furthermore, a cubic relation correlation was established, relating the month number (X) and the monthly average of the daily specific yield (Y). It was found that installing a solar PV system will cut about 39.0% of CO2 annually, which is equal to 4.637 tons and hence saves 38,567 ft3 of natural gas. The initiative of encouraging the use of rooftops in Bahrain to produce zero-carbon electricity is a step towards retrofitting the built environment to combat climate change.

Hybrid Decentralized Systems of Non-potable Water Supply: Performance and Effectiveness Analysis

This article presents a study of Hybrid Rainwater/Greywater Systems (HRGS), with the objective of perceiving the main factors that influence their performance and how they can be optimized. For this goal, a decision support tool, that makes their dimensioning and performs an economic and performance analysis, was used for four different types of buildings: a single-family house, a multifamily building and two service buildings. For each case, distinct scenarios were defined, considering different end-uses of non-potable water, in order to evaluate the performance of the systems using effectiveness and performance indicators. Results show that the effectiveness of “non-potable water consumption” is influenced by two main factors: the final uses considered for non-potable water and the storage volume. In most of the study cases, values of effectiveness (ratio between the volume of non-potable water used and non-potable water demand for the final uses considered) greater than 50% were obtained. In the case of domestic buildings, such as single-family house and multifamily building effectiveness values above 67%, were obtained. And for the case of service buildings, the effectiveness was between 42.8 and 65.6% in one case, and between 12.9 and 93.6% for the other. The best performance of the studied hybrid systems is achieved when the volume of non-potable water used in the building is maximized, resulting in greater savings of potable water. In addition, the larger the fraction of greywater reused, the lower the volume of wastewater produced and sent directly to the sanitation network.

Multi-Objective Optimization of Ultra-Low Energy Housing in Hot Summer Cold Winter Climate Zone of China Based on a Probabilistic Behavioral Model

Occupant behavior has an important impact on building energy consumption, and the accuracy of an occupant behavior model directly affects the reliability of energy consumption simulation results. Ultra-low energy buildings are crucial to achieving building energy conservation and carbon dioxide reduction in China. In order to effectively promote the development of ultra-low energy buildings in Hot Summer and Cold Winter Climate Zones. where most residents adopt a “part-time, part-space” pattern of intermittent energy use behavior, and to solve the problem of poor indoor thermal environments and the high incremental cost of ultra-low energy, the study described in this paper takes Changsha as an example to carry out a multi-objective optimization study on ultra-low energy housing using a probabilistic behavioral model. On the basis of a probability model representing the residents’ actual behavior in Changsha, the optimization objective indicators, key variables and the technology benchmarks for ultra-low energy building were determined, then multi-objective optimization was carried out for a range of energy efficient technologies to obtain the Pareto optimal solutions. The results showed that the set of optimal solutions could reduce energy demand by 50.2 to 60.2% and reduce indoor thermal discomfort time by 3.52–11.09% compared with those of a reference base case, which just meets the requirements of the current design standard for energy efficient domestic buildings. An optimum solution for energy savings and indoor thermal comfort, along with economic costs, was identified, which can assist in decision-making by providing different preferences and provide useful reference for the design of ultra-low energy buildings in Hot Summer and Cold Winter Climate regions.

Application research of traditional elements in architectural decoration design under the background of big data and IoT

Under the background of big data and the Internet of Things, different design elements in domestic architectural design are becoming more and more abundant. During the integration of different elements, traditional elements are an important part of the domestic building decoration industry. In the integration of the entire architectural style, it is integrated with the entire architectural style. It reflects the deep heritage of traditional culture. Many scholars have conducted in-depth research on this phenomenon, but how to better apply big data technology to promote the application of traditional elements in the field of architecture is still blank. This paper establishes a scientific evaluation model according to the different proportions in the application of traditional architectural elements and its proportion in the external display of actual buildings, which opens up new ideas for research in this field. This article studies the application and development prospects of the traditional elements of the architectural decoration industry in my country, and explores the innovative development of traditional decorative elements in the modern architectural decoration industry. Study the development needs of modern aesthetic design in the current stage of the building decoration industry. Through the rich and innovative application survey of traditional elements, the vitality in modern architectural decoration that stimulates traditional culture, and continuously enriches the extensive development and innovative development of the domestic building decoration industry. Stimulates the importance of traditional architectural decoration elements. This article conducts statistics and analysis of the big data and decoration requirements of the domestic decoration industry, applies the computing and evaluation model in the field of architecture, and evaluates the application of traditional elements in the field of architectural decoration more coordinated development. Looking at the existing research results, they all put forward suggestions for development at a macro level, but there is a blank on how to choose the ratio of various traditional factors more scientifically. In order to solve this problem, the research has created a scientific calculation model. Traditional factors are used for assignment and big data is used for calculation, which provides new ideas for research in this field.

THEORETICAL ASPECTS OF AVOIDING DELAMINATION OF COMPOSITE MATERIALS DURING STRENGTHENING OF REINFORCED CONCRETE STRUCTURES

The scientific work is devoted to the improvement of the calculation methodology of reinforced concrete elements, using verification of the FRP delamination prevention, during structures strengthening with a system of composite materials (SCM) from various fibers types. During strengthening of reinforced concrete elements with composite material systems, the role of adhesion between concrete and FRP is of great importance due to the fragility of the failure mechanism due to delamination (loss of adhesion). The adhesion strength is generally much higher than the tensile strength of the concrete, so delamination always starts in concrete itself with the separation of FRP layer of different thickness. According to the load-bearing capacity requirements, such a failure mechanism should not precede the failure of the strengthened element during bending or shear. To solve the problem of possible strengthening delamination of composite materials systems, it is necessary to consider different failure modes of FRP. Due to imperfection of domestic building codes, a detailed analysis of the solution to the problem of FRP delamination was carried out in accordance with the recommendations of a number of foreign regulatory documents (ACI, CNR, FIB). The main failure modes, with subsequent initiation of delamination of FRP material from concrete base, are systematized, namely: FRP delamination due to surface irregularities, separation of FRP due to shear cracks, longitudinal shear stresses in the yield zone, excessive deformations in FRP material (FRP rupture), longitudinal shear stresses near the FRP edges, failure in anchoring (fixing) zone of FRP material. Six criterions are proposed that need to be verified during design of structures strengthening systems with FRP materials. During formulation of specified criterions, the main theoretical aspects necessary for application in structural calculations of the studied connection are given. The results of research can be used in future during the design of structures joints strengthening with systems of composite materials based on carbon fibers, glass, aramid. Keywords: system of composite materials, external reinforcement, FRP strengthening, reinforced concrete, failure mode, calculation, delamination.

Twenty-five Years of Excavations in Brigetio at the Site Komárom/Szőny-Vásártér

Brigetio, along the Danube limes, was one of the four legionary bases of Pannonia and, thus, one of the most important settlements of the province. The excavations conducted by the Eötvös Loránd University and the Klapka György Museum of Komárom lasted 25 years (1992–2016) and yielded unparalleled information about the spatial structure and the temporal setting of the Roman municipium. Numerous high-standard domestic buildings with hypocaust heating systems and figurative wall paintings were brought to light by the excavations. Besides, traces of several workshops were discovered, including a metal and a secondary glass workshop and a bakery. Based on the countless small finds collected during the excavations, the civil town seems to have existed from the turn of the 1st and 2nd centuries AD to after the mid-3rd century AD when the inhabitants abandoned the municipium. The heyday of the settlement can be dated to the first half of the 3rd century AD; most findings and building remains came from this period. This paper summarizes the results of each excavation season with drawings and references to the most important small finds.

The impact of teleworking on domestic energy use and carbon emissions: An assessment for England

Despite decades of research on the environmental impacts of teleworking, most studies have neglected building-related energy use and emissions. Even fewer studies have explored the relative influence of different variables on those emissions. This study therefore explores the building-related emissions from teleworking in England using data from the UK Energy Performance Certificate (EPC) database over the period 2008 to 2022. We use a building energy model to estimate the additional emissions associated with different patterns of teleworking, including variations in heated area and internal temperature. We combine our results with a separate set of estimates of the transport-related emissions. We also employ global sensitivity analysis to identify the relative importance of different variables.We find that English teleworkers have significantly higher emissions than non-teleworkers. Considering both transport and domestic building emissions, working from home 3–5 days/week leads to 3% less to 17% more carbon emissions than conventional work patterns depending on the heating area, heating system heating time and required temperature. We find that heating area has the biggest influence on building emissions, followed by the number of heating hours, wall insulation and the efficiency performance and carbon intensity of the heating system.

Towards net-zero emissions concrete and steel in India, Brazil and South Africa

ABSTRACT Working with in-country modelling teams and models, targeting net-zero CO2 emissions by later this century, and using decomposition and emissions driver analysis, we develop low emissions cement and steel scenarios linked to usable policy levers for Brazil, India, and South Africa. We find significant mitigation potential from a ‘current policy’ scenario on the demand side (13–26%) and the production side (58–71%), but these countries’ substantial needs for more basic infrastructure – and thus for cement and steel inputs – indicate net-zero will remain very challenging. Demand-side material efficiency reductions, where less steel and cement deliver the same service through better design, will require decades of educational and regulatory efforts, working with buildings sector and infrastructure supply chain actors to reach full potential. In the short to medium run, focusing on reducing emissions from production may deliver more near-term cumulative mitigation by allowing close attention to a small number of domestic companies with high managerial, technical, and financial capacity. To achieve such reductions, governments should encourage the concentration of cement and concrete making at professional facilities to allow the use and regulation of already commercialized lower GHG practices like cementitious material clinker replacement and better concrete mixing while planning for future carbon capture and storage. Governments should also encourage investment in secondary steel making using electric arc furnaces to reuse local recycled scrap, eventually supplemented with increasingly low emission primary iron. International cooperation and support are needed to agree on and implement CO2 intensity accounting systems, improve access to low-emissions production technologies through innovation and commercialization combined with technology transfer or co-development, and offer financial and technical support for clean production investments. Key policy insights On the demand side, international buildings organizations and domestic building code regulators should work with architects, structural engineers, and construction companies to implement regionally appropriate material efficiency options. On the production side, international cement and steel organizations, governments and domestic firms should explore cooperation on technology innovation and transfer, finance, and private and public lead market mechanisms, e.g. premia for low emission production and green procurement. Adaptive long-term sectoral strategies addressing demand and supply will need to be developed with all affected parties.

Innovative Data-Driven Energy Services and Business Models in the Domestic Building Sector

The market of energy services for the residential sector in Europe is very limited at present. Various reasons can be argued such as the high transaction costs in a highly fragmented market and the low energy consumption per dwelling. The rather long payback time for investments render Energy Services Companies’ (ESCOs) services financially unattractive for many ESCOs and building residents, thus hindering a large potential of energy savings in a sector that is responsible of almost half of Europe’s energy consumption. If the ambitious 2030 and 2050’s decarbonisation targets are to be met, the EU’s residential sector must be part of the solution. This paper offers insights about novel ESCO business models based on intensive data-driven Artificial Intelligence algorithms and analytics that enable the deployment of smart energy services in the domestic sector under a Pay-for-Performance (P4P) approach. The combination of different sources of energy efficiency services and the optimal participation of domestic consumers in aggregated demand response (DR) schemes open the door to new revenue streams for energy service providers and building residents and reduce the hitherto long payback periods of ESCOs services in the sector. Innovative business models for ESCOs and demand flexibility Aggregators are thoroughly described. Especially customised Performance Measurement and Verification protocols enable fair and transparent P4P ESCO contracts. The new human-centric energy and non-energy services increase the energy consumption awareness of building users and deploy behavioural and automated responses to both environmental and market signals to maximise the economic benefit for both energy service providers and consumers, always respecting data protection rules and the consumers’ comfort preferences. The new hybrid business models of P4P energy services make traditional EPC more attractive to energy service providers, with low cost data collection and treatment systems to bring payback periods below 10 years in the residential building sector.

Cooling is hotting up in the UK

The cooling of buildings is currently responsible for about 20% of total electricity use worldwide. It is estimated that the electricity needed for cooling will more than triple by 2050. Despite this concerning outlook, little attention has been paid to cooling demand in policy and research in the United Kingdom (UK). The demand for space cooling in the UK’s domestic and non-domestic buildings is currently small—about 10% of total electricity use. However, this has the potential to increase as the climate warms and expectations of comfort grow. This paper reviews UK cooling demand and how this has been considered in energy policy. Following a thorough review of the existing literature using a cooling decarbonisation framework (Avoid, Improve and Shift), it is clear there is a limited understanding of the future UK cooling demand for domestic buildings in a warmer future as well as how policy makers and households should act. More importantly, this sector appears under-represented in the UK research and policy landscape compared to heating despite obvious technological crossovers associated with electrification. Several policy and research recommendations have been made based on these findings.

Design of an EnergyPlus Model-Based Smart Controller for Maintaining Thermal Comfortable Environment in Non-Domestic Building

Heating, Ventilation and Air Conditioning (HVAC) systems account for 59% of energy consumption in domestic buildings and 36% in non-domestic buildings. According to a study, around 39% of occupants are dissatisfied with indoor temperature in non-domestic buildings. To maintain thermal comfort and indoor air quality, HVAC systems are widely used in non-domestic buildings. This research aims to develop energy-efficient control techniques for HVAC systems while ensuring indoor thermal comfort. Three control strategies, namely EnergyPlus model-based Model Predictive Control (MPC), Sliding Mode Control (SMC), and simple ON/OFF control, are employed and compared at the Department of Electrical and Computer Engineering, COMSATS University Islamabad, Lahore Campus. Furthermore, a machine learning-based Predicted Mean Vote (PMV)-based temperature setpoint estimator is designed to ensure occupant thermal comfort. The control techniques estimate the temperature setpoints and supply air temperature of the Variable Air Volume (VAV) system to control indoor room temperature. The energy consumption and indoor thermal comfort of the building are compared under different control techniques. The results show that MPC with PMV-based setpoints consumes 17.20% less energy during winters and 14.67% less energy during summers than a simple ON/OFF controller.

에너지성능평가를 위한 지역별 창호설치열교에 관한 연구

The purpose of this study is to propose the value of window installation thermal bridge by region. Domestic building standards and construction methods in the market were considered for the window installation thermal bridge. In this study, the Window installation thermal bridge value was applied to the actual remodeling building. As a result of the thermal bridge application, the window performance drop rate due to the window installation thermal bridge was up to 220% and the smaller the window, the greater the performance drop. The improvement rate of building energy requirement decreased from 15.1% to 8.3%.