Energy Consumption Of Dwellings Research Articles

The impacts of residential buildings’ energy compliance standards on Iran’s GHG emissions toward achieving the Paris Agreement

Countries have been driven to undertake energy conservation measures to lessen their negative environmental effects due to rising CO2 emissions worldwide. To effectively forecast the future status and evaluate the efficacy of energy-saving and mitigation scenarios, estimating energy consumption and the associated CO2 emissions from fossil fuels is essential. The domestic sector in Iran, liable for using around 30% of the total energy consumption, is the focus of this research. The research has developed a model for future energy consumption and greenhouse gas emissions distinctive to the features of the Iranian residential building stock by considering climate change and using statistical data. To assess prospective results, the Business-As-Usual and energy conservation scenarios are compared. The research also evaluates the potential of energy savings and CO2 reduction across several provinces. The fulfillment of the energy compliance requirements confined in the National Building Regulations by considering the impact of climate change on energy consumption in dwellings of different climate regions has been prioritized. The results show that under different mitigation scenarios, CO2 emissions in the household sector are projected to decrease by 15.7%, 18.4%, 26.8%, and 31.8% by 2030 and 2050. According to the Paris Agreement, these reductions are consistent with Iran's Intended Nationally Determined Contribution. The study emphasizes the significance of targeted measures and policy implementations to lower CO2 emissions in the domestic sector substantially, supporting global efforts to mitigate climate change. The methodology described here addresses energy-related challenges within the constraints of available data on the residential building stock statistic. While acknowledging the potential for further refinement, the country's development of a detailed typology of residential buildings holds promise for enhancing the precision of the modeling in future studies and enabling more robust assessments of energy-saving strategies.

The Influence of Residential Behavior on Dwelling Energy Consumption and Comfort in Hot-Summer and Cold-Winter Zone of China—Taking Shanghai as an Example

Human behavior plays a key role in building energy consumption, especially in residential buildings. Residents in the hot-summer and cold-winter zone of China tend to use energy in a “partial-time, part-of-the-space” manner. With the improvement in people’s living standards, the energy consumption of residential buildings in this region has been increasing. Exploring the building energy efficiency methods that suit the local residents’ energy use habits while ensuring building comfort levels is of great importance. This paper investigates the impact of living behavior on residential energy consumption and comfort in this region, focusing on personnel-in-room conditions, use of air-conditioning equipment, and window opening. Firstly, a questionnaire survey was conducted to analyze the energy use behaviors and the mentality of residents in the Jiangsu–Zhejiang–Shanghai Area of China. Then, based on the current situation of the household structure in Shanghai, 10 households were selected and monitored for a period of 8 months. Their energy use patterns were summarized to obtain a standard sample. Finally, the energy consumption simulation software DeST 2.0 was used to analyze the impact of each usage element on comfort and energy consumption. A dual-index evaluation of energy consumption and comfort is proposed for the first time. This paper found that respondents placed about a 6:4 important ratio on “comfort” and “energy efficiency” in their dwellings and that the importance placed on comfort increased from low-energy to high-energy households. Behaviors such as “gathering more in the living room” and “open windows as much as possible in the summer and appropriately in the winter” were more beneficial to both comfort and energy efficiency.

Energy-Consumption Pattern-Detecting Technique for Household Appliances for Smart Home Platform

Rising electricity prices and the greater penetration of electricity consumption in end-uses have prompted efforts to set up data-driven methodologies to optimise energy consumption and foster user engagement in demand-side management strategies. The performance of energy-management systems is greatly affected by the consumer behaviors and the adopted energy-management methodology. Consequently, it is necessary to develop appliance-level, detailed energy-consumption information models to inform citizens to improve behaviors toward energy use. The goal of the Home Energy Management System (HEMS) is to foster an ecosystem that is energy-optimized and can manage Internet of things (IoT) equipment over its network. HEMS allows consumers to reduce energy costs by adapting their consumption to variable pricing over the day. With the use of descriptive data-mining techniques, we have developed a numerical model that gives consumers access to information on their domestic appliances with regard to the number and duration of operations, cycles disaggregation for appliances that have cyclic operation (e.g., washing machine, dishwasher), and energy consumption throughout various time periods basing on 15-min monitoring data. The model has been calibrated and validated on two datasets collected by ENEA by real-time monitoring of Italian dwellings and has been tested over several appliances showing effective analysis of the energy-consumption patterns. Therefore, it has been integrated in the DHOMUS IoT platform, developed by ENEA to monitor and analyse the energy consumption in dwellings in order to increase citizens’ engagement and awareness of their energy consumption. The results indicate that the developed model is sufficiently accurate, and that it is possible to promote a more virtuous and sustainable use of energy by end users, as well as to reduce the energy demand as required by the current European Council Regulation (EU) 2022/1854.

Effect of balcony forms difference on indoor thermal environment and energy saving performance of multiple-dwelling house

By optimizing the design of the building envelope, it is possible to create a more comfortable and energy-efficient indoor environment for the occupants. However, due to environmental issues in high-density cities, open balconies might affect the health of occupants. The current research focuses on the effect of a single balcony form in different climates, which could be detrimental to the diversity of balcony designs. Therefore, it is necessary to re-examine the rationality of traditional Japanese open balconies in terms of building envelope design and living environment to optimize the indoor thermal environment and reduce the energy consumption of dwellings. Focusing on Kitakyushu, Japan, which is in a warm climate, this paper conducts a comprehensive comparative study of the effects of building envelope design for residential buildings, including balcony form, thermal insulation performance, room orientation, and the window-to-wall ratio of balcony facades. The results of the study indicate that 1) the closed balcony design is strongly applicable to houses in warm climate regions in winter; 2) closed balconies facing south have a more positive impact on the indoor thermal environment, and energy-saving performance than open balconies; 3) even closed balconies without insulation could achieve higher thermal environment gains than open balconies with insulation. Designing a special type of closed balcony for residences in winter is more energy-efficient than insulation. This study proposes architectural envelope designs that are adapted to specific environmental and climatic conditions. It contributes to providing residential designers with a measure of how to provide a comfortable residential thermal environment and energy efficiency for occupants through architectural envelope design.

The energy performance of dwellings with heat pumps of Dutch non-profit housing associations

ABSTRACT Achieving energy efficiency in the built environment requires extensive efforts in the renovation and adaptation of housing stock. A promising design solution is the heat pump. While gas boiler systems are commonly used in Dutch non-profit housing stock, the share of dwellings with a heat pump grew from 1.6% in 2017 to 3.2% in 2021. However, building characteristics and the energy consumption of dwellings with a heat pump are unclear. Therefore, a dataset of 69,422 dwellings with different types of heat pumps has been examined and compared to dwellings with a traditional HR107 condensing gas boiler. This research reports average characteristics and the average actual energy consumption of dwellings with all-electric, hybrid and gas absorption heat pump systems. Dwellings with a heat pump system are on average of higher building quality, their gas consumption is lower and their electricity consumption is higher than dwellings with an HR107 condensing gas boiler. Detailed insight is provided for dwellings with different heat pump systems and for dwellings with different building characteristics. Further research to determine the energy performance of dwellings with specific heat pump configurations is recommended in light of the energy transition in the built environment.

Optimization of Plane and Space of New Dwellings in Southern Anhui Province Based on Indoor Thermal Environment

Considering the problems of poor plane and space design, poor indoor thermal environment, and high energy consumption of dwellings in southern Anhui province, and combining with the requirements of modern residential environment, the characteristics and changing laws of the plane and space organization of Huizhou traditional dwellings from the traditional period to the New Rural period and the inheritance requirements of Huizhou traditional dwellings, seven types of new dwellings in southern Anhui province were designed based on the survey and mapping of Huizhou traditional dwellings. DesignBuilder software is used for the new dwelling plan to simulate and optimize the indoor thermal environment as well as energy consumption of seven building plans. The results show that: High indoor thermal comfort and low energy consumption are observed in a large aspect ratio and fully enclosed room, and better indoor thermal comfort is observed in summer than in winter in rooms with courtyards, and better indoor thermal comfort and low energy consumption is observed when the rooms are located in the northeast, southwest, and south directions. The results have guiding significance for the construction of new dwellings that are comfortable and energy-saving, and distinctive in southern Anhui province.

Towards a future sustainable housing stock

This thesis examines the energy performance of dwellings of Dutch non-profit housing associations towards a future sustainable housing stock. Improving the energy performance of dwellings aims to improve the quality of dwellings and therewith to lower the actual energy consumption. Lowering the actual energy consumption of dwellings contributes to the battle against climate change. This thesis addresses four studies. Study 1 assesses the energy performance progress of over two million dwellings of Dutch non-profit housing associations between 2017 and 2020. It gives insights into the development of the housing stock, the effect of changes of and within the stock, the effect of characteristics of housing associations and it relates the improvement of the energy performance to the sectoral goal. Study 2 assesses advanced models to improve estimations of actual energy consumption of dwellings and therewith to better estimate the effect of renovation measures on actual energy savings. Study 3 assesses the energy performance of dwellings with heat pumps. It gives insights into the energy performance of dwellings with heat pumps as a promising renovation measure towards a future sustainable housing stock. Study 4 assesses the process to create a model to benchmark the energy performance in a changing policy context. The four studies contribute to the understanding of the improvement of the energy performance of dwellings of non-profit housing associations towards a future sustainable housing stock.

The energy performance of dwellings of Dutch non-profit housing associations: Modelling actual energy consumption

In Europe, the energy performance of dwellings is measured using theoretical building energy models based on the Energy Performance of Buildings Directive (EPBD), which estimates the energy consumption of dwellings. However, literature shows large performance gaps between the theoretically predicted energy consumption and the actual energy consumption of dwellings. The goal of this paper is to investigate the extent to which empirical models provide more accurate estimations of actual energy consumption when compared to a theoretical building energy model, in order to estimate average actual energy savings of renovations. We used the Dutch non-profit housing stock to demonstrate the results. We examined three empirical models to predict the actual energy consumption of dwellings: a linear regression model, a non-linear regression model, and a machine learning model (GBM). This paper shows that these three models alleviate the performance gap by giving a good prediction of actual energy consumption on sectoral cross-sections. However, these models still have shortcomings when predicting the effects of specific renovation interventions, for example newly introduced heat pumps. The non-linear and machine learning model (GBM) outperform the theoretical model in terms of estimating energy savings through renovation interventions.

Personal Heating in Dwellings as an Innovative, Energy-Sufficient Heating Practice: A Case Study Research

Despite the efforts to improve the energy efficiency of buildings, the actual energy consumption decreased much less than expected in recent years. Therefore, energy sufficiency is gaining attention as a complementary approach to energy efficiency. It aims to reduce the actual energy consumption of buildings by providing thermal comfort to residents in a sufficient way. This demands for alternative heating practices, such as the application of personal heating systems. Although a review of past studies shows that, in office buildings, thermal comfort can be provided with less energy by using personal heating systems, the application in a residential context is much less explored. Our hypothesis is that an innovative, energy-sufficient personal heating practice also has potential to reduce the overall energy consumption in dwellings. Therefore, this paper presents the results of a one-week case study on personal heating as an energy-sufficient heating practice in three dwellings. During the case study, the ambient temperature was reduced to 18 °C, and residents were allowed to use active and passive personal heating systems to make themselves as comfortable as possible. They were also asked to evaluate their thermal sensation and thermal comfort. The results show that, despite a lower indoor temperature, residents are able to achieve thermal comfort by using personal heating at the locations where they effectively reside. Additionally, a significant energy saving potential was found. The case study proved our hypothesis, leading to the conclusion that an innovative, sufficient personal heating practice in dwellings can be a supplementary step to reduce the energy consumption to meet the global challenges.

Climate change and income inequality: An I-O analysis of the structure and intensity of the GHG emissions in Mexican households

Household consumption is not sufficiently studied in climate change research, despite the fact that it is a variable related to GHG emissions. The objective of this paper is to assess the amount, structure, and intensity of total GHG emissions (direct and indirect) related to Mexican household consumption by income level by means of an Input-Output analysis. Our study produced the following three main findings: 1) Large carbon inequality among household income groups, with the bottom household decile emitting 2.7% of the total CO2e emissions, and the top decile emitting 26.8%. 2) Three needs are the main drivers of carbon emissions of Mexican households: transportation (39.9%), dwelling energy consumption (26.9%), and food (15.2%). The share of transportation (public and private) is higher when the households are in higher deciles (24% in the bottom decile vs 40% in the top decile). Private transportation in the top decile is of particular concern. The CO2e emissions from private transport from the richest decile represent more than 10% of the total CO2e emissions. 3) The total carbon intensity of the household expenditure is depicted in an obtuse inverted U curve as a function of income distribution. The top and the bottom deciles present the lowest carbon intensities because of the composition of their basket of consumer goods and services. In the top decile, there is a significant share of expenditure on financial and educational services (with low carbon intensity), while in the bottom decile there is a high proportion of low-carbon basic products such as food. From all these results, we concluded that, in order to be effective and sustainable from a social and economic point of view, the formulation of policy to mitigate GHG must take into account both household income inequality and the diverse quantity and structure of consumption as a function of income level.

A Review of Balcony Impacts on the Indoor Environmental Quality of Dwellings

Balconies are an ancient architectural archetype that are being increasingly considered in multi-family buildings of high-density cities. This paper aims to provide a comprehensive review of the impacts of balcony types on the indoor environmental quality (IEQ) and energy consumption of dwellings. Of the reviewed studies, 69% were published during the last decade, making it evident that awareness of the positive impact of balcony spaces is continuously increasing. The literature review allowed us to identify three balcony spaces according to their morphology and their boundary system: open balcony (OB), glazed balcony (GB), and eliminate balcony (EB). It was concluded that these balcony types produce relevant impacts in four factors that contribute to the indoor environmental quality: thermal comfort, indoor air quality, visual comfort, and acoustic comfort. Practical design recommendations and constraints were provided according to distinct climatic conditions and building technologies. This review also explored the assessment methodologies used for the optimization of the balconies on the design process. The literature highlighted the lack of a comprehensive study about the impact of balconies in mild and Mediterranean climates, as well as the knowledge limitations concerning the balance between the impacts on IEQ factors.

Strategy of Container Assembly for a Positive Energy Impact in Poona India

Every year the Indian government is involved in the construction of nearly two million new buildings excluding the tertiary sector. These homes are not only intended primarily to house Indian populations, but the authorities concerned have also placed emphasis on sustainable development, since as all over the world the residential sector is the one that consumes the most energy. Indeed, active and passive strategies to reduce the energy consumption of dwellings have been established and even applied. Among the passive strategies, the global shape of the building, initially specific to modular architecture impacts the aesthetic part of the building but also its energetic bills. The concept of modular architecture is mainly the assembly of identical cells and, in different ways, the overall energy consumption depends on the initial assembly of the cells and therefore on the resulting shape of this assembly. The purpose of this article is to determine the impact of the shape on the energy balance. For this study, the container is the archetype used, in fact the metal box being a standardized, economical and easily transformable product in living space. The complex system resulting from the assembly of several containers offers a new way of thinking about housing from an architectural, economic, aesthetic and energetic point of view. In this article, we will focus on studying the impact of the overall shape of container-type housing on annual energy bill, with the aim of optimizing energy efficiency and achieving an eco-container model that meets international eco-sustainability criteria. The results demonstrate the undeniable correlation between geometric and energy aspects, the latter being mainly related to the internal thermal comfort of the container housing cells.

Mejora de la calidad de la energía con sistemas fotovoltaicos en las zonas rurales

Se expone un análisis vinculado a una de las alternativas energéticas sostenibles que en la actualidad se está adoptando con éxito a nivel mundial con el fin de lograr el mejoramiento de la calidad del servicio eléctrico, ahorrar recursos naturales, reducir las pérdidas y contribuir en la disminución de las emisiones de CO2 a la atmósfera. Se muestran los resultados de un estudio relacionado con el uso de una innovación tecnológica para mejorar la calidad del servicio eléctrico en una comunidad aislada, mediante la introducción de tecnología fotovoltaica conectada a la red de baja tensión de un grupo de 20 viviendas que fueron estudiadas. Se muestran los resultados del estudio de carga y consumo horario de energía de las viviendas y se despliega una metodología propia para el diseño de la tecnología fotovoltaica conectada a la red de baja tensión de las viviendas estudiadas; este tiene el potencial de evitar el consumo de energía de la red convencional y la posibilidad de mejorar la calidad del servicio eléctrico, al tiempo que se reducen el monto de la factura eléctrica y las pérdidas.

Comparison of prediction tools to determine their reliability on calculating operational heating consumption by monitoring no-fines concrete dwellings

Nowadays most retrofit decisions are based on reducing CO2 / heating consumption. The aim of this study was to determine the reliability of three tools (RdSAP, SAP and IES) often used to predict these reductions. Three no-fines concrete (NFC) dwellings (C1, C2, and C3) with similar floor area and construction but different occupants were monitored. Key information about the thermal performance of the fabric; the behaviour of the occupants and the energy consumption was collected before and after 110 mm of external wall insulation (EWI) was added. The target was a 30% reduction on energy consumption due to the EWI. However, only C3 decreased it by 30% as expected, C2 only by 14% due to a subtle rebound effect and C1 actually increased consumption by 75%, due to rebound effect.Steady state tools (RdSAP and SAP) were found to be inaccurate in predicting the operational energy consumption of dwellings, only dynamic performance analysis software (IES) was suitable to carry out this type of prediction accurately. However, this type of software requires highly accurate and detailed information regarding: the baseline performance of the fabric, external weather conditions and, most importantly, accurate pre- and post- heating operational habits of the occupants. Few retrofitting projects have the resources and time to gather this information. Unless those are available, the retrofit decisions should be based in a different criteria, rather than using inaccurate SAP or RdSAP energy consumption predictions.The coefficient of heat loss of the fabric of a dwelling is independent of the occupants. SAP was found quick to calculate reasonable predictions of the coefficient, by using accurate fabric data, and to show the impact of different factors on the heat loss of the fabric. Therefore, it could be claimed that the coefficient of heat loss of the fabric is a suitable alternative criteria to make pre-retrofit decisions.

A modelling study for the integration of a PEMFC micro-CHP in domestic building services design

Fuel cell based micro-combined heat and power (CHP) units used for domestic applications can provide significant cost and environmental benefits for end users and contribute to the UK’s 2050 emissions target by reducing primary energy consumption in dwellings. Lately there has been increased interest in the development of systematic methods for the design of such systems and their smoother integration with domestic building services. Several models in the literature, whether they use a simulation or an optimisation approach, ignore the dwelling side of the system and optimise the efficiency or delivered power of the unit. However the design of the building services is linked to the choice of heating plant and its characteristics. Adding the dwelling’s energy demand and temperature constraints in a model can produce more general results that can optimise the whole system, not only the micro-CHP unit. The fuel cell has various heat streams that can be harvested to satisfy heat demand in a dwelling and the design can vary depending on the proportion of heat needed from each heat stream to serve the energy demand. A mixed integer non-linear programming model (MINLP) that can handle multiple heat sources and demands is presented in this paper. The methodology utilises a process systems engineering approach. The model can provide a design that integrates the temperature and water flow constraints of a dwelling’s heating system with the heat streams within the fuel cell processes while optimising total CO2 emissions. The model is demonstrated through different case studies that attempt to capture the variability of the housing stock. The predicted CO2 emissions reduction compared to a conventionally designed building vary from 27% to 30% and the optimum capacity of the fuel cell ranges between 1.9 kW and 3.6 kW. This research represents a significant step towards an integrated fuel cell micro-CHP and dwelling design.

Thermal and climatic zoning for construction in the southern part of Chile

Abstract. This paper presents the results of the updated boundaries of thermal zones in the tree southern regions of Chile, based on the method of heating degrees-days according to hourly temperature measurements at meteorological stations in the last decade. The Ministry of Housing and Urban Planning of Chile has not updated these boundaries since 1999. Using the Climatic Severity index method, the relative energy consumption of dwellings was analyzed for cooling and heating in summer and winter periods, respectively. The analysis revealed that, within the limits of a single thermal zone, the energy costs for cooling in the summer period of the same house may differ by 50 %.

Conclusion

In spite of the technological advancement on building design and construction, actual energy use levels of dwellings are different than expected in several cases. Little is known about how occupants interact with their dwellings, what the background to this interaction is, as well as the resulting energy use. This research aimed at revealing the relationship between occupant behavior and energy consumption, both in terms of heating energy and electricity. The determinants of occupant behavior, the sensitivity of dwelling energy consumption to occupant behavior, and defining behavioral patterns/profiles are the main elements of this work. This thesis will help to understand the occupant related factors of energy consumption in dwellings, by this way designing better products, energy management systems, software, and achieving better regulations. Research on energy consumption of dwellings covers thorough investigation of the behavioral performance during the occupancy process, as well as the aspects that are involved in the design and building processes. There has been extensive progress on the building physics aspects of energy consumption; concerning methods and practices for specification of building geometry, material properties, and external conditions. However, the resolution of input information regarding occupant behavior is still rather low. In order to respond to this, one of the research questions of this thesis has been: what is the sensitivity of dwelling energy consumption to occupant behavior? Secondly, the influence of lighting and appliance use on electricity consumption, as well as the determinants of electricity consumption in dwellings, and lastly, the behavioral patterns of energy consumption are investigated. This study’s methodological approach combined the deductive and the inductive methods, by considering both the determinants of behavior and the actual behavior itself. Deductive methods dissect energy consumption into its factors, such as household characteristics, dwelling characteristics, behavioral aspects, etc. On the other hand, inductive methods model actual behavior from bottom up experimenting and validating energy consumption levels. In this thesis, occupant behavior was considered as presence patterns in a space, together with the actual heating (thermostat setting and radiator control) and ventilation patterns (operation of windows, grids, and mechanical systems), and the use of lighting and appliances. This research looked at the building and household characteristics that determine occupant behavior, as well as habitual (surveyed) and actual (monitored) occupant behavior.

Introduction

There is an increasing need for ensuring high energy savings throughout the building lifecycle, from the early design phases until post occupancy. Utility (services) and firmness (robustness) are principles of good design since Vitruvius, but sustainability was added as a new principle after 1980s, for a distinct understanding, evaluation and action development on energy consumption and environmental impact of buildings. Today, we are able to measure the consumption levels and environmental impact of our buildings, manage their indoor comfort, and combine this further with our personal desires. Sustainability means decreasing waste and pollution, the demand for physical resources (energy, material…) and the impact on climate change, while maintaining the indoor comfort and health conditions in a building. Design decisions for sustainability include that of land use, microclimate management, form, spatial organization, building envelope, and managing water, waste, and energy systems. The essence of sustainability lies in designing all these factors with a holistic approach, while making sure that the building is usable for the occupant. Energy efficient housing requires less energy and uses renewable energy resources in the most efficient way for the energy needed during occupancy. Kim and Rigdon (1998) define the three basic principles of sustainable design as efficient use of resources (reduce, reuse, recycle); assessment of resource consumption during construction and use; and human centered design (the interaction between the human being and the environment). This research addresses the latter, the human aspect. The buildings’ energy consumption estimated by simulation software can be validated in total, only during occupancy, when the design is tested on actual use. For residential buildings, we know that sometimes the actual energy use levels are different than the expected/calculated (Lutzenheiser, 1992; Jeeninga et al., 2001; Guerra Santin, 2010; Majcen, 2013). A couple of reasons to this can be calculation drawbacks, incorrect construction applications and unexpected occupant behavior. Therefore, better understanding of the relationship between occupant behavior and energy consumption can enable more efficient design and operation of (residential) buildings, which are more suitable to the occupants’ use considering thermal, acoustical, visual, environmental comfort, health and safety. Policy on energy efficiency in buildings focuses mostly on building characteristics and mechanical systems like heating and ventilation. Although there is strong evidence for the influence of occupant behavior on energy consumption, the effort made to gain more insight to this relationship stayed behind for a long time. This study addresses the influence of occupant behavior on energy consumption for heating and electricity use for appliances and lighting, in residential buildings. This research is conducted as a joint effort at Delft University of Technology, Faculty of Architecture, between the chair of Design Informatics; research program Computation and Performance, and the chair of Housing Quality and Process Innovation (HQPI). Chair Design Informatics, research program Computation and Performance aims to improve the performance of buildings by using computational methods for model generation and analysis, decision-making and design communication, in an interdisciplinary context. This research could contribute to the further development of computational model(s) and tools in support of user’s decision-making processes. Furthermore, one of the research goals of chair HQIP is to understand the influence of occupant behavior to energy consumption in dwellings. The PhD research of Guerra Santin (2010) and Majcen (2016) of the chair HQIP specifically focus on occupant behavior and energy consumption. This research is built partially on the same datasets as Guerra Santin (‘OTB dataset’ and ‘WoON survey’), with different research questions. Findings of Guerra Santin and Majcen’s research are referred to, in the relevant sections of this thesis. Most of the research conducted under the title of this PhD was published between 2009 and 2013.

Occupant behavior and energy consumption in dwellings: An analysis of behavioral models and actual energy consumption in the dutch housing stock

Much is known about the increasing levels of energy consumption and environmental decay caused by the built environment. Also, more and more attention is shown to the energy consumption of dwellings, from the early design stage until the occupants start living in them. The increasing complexity of building technologies, the occupants’ preferences, and their needs and demands make it difficult to achieve the aimed energy consumption levels. The goal of reducing the energy consumption of dwellings and understanding the share of occupant behavior in it form the context of this research. Several studies have demonstrated the ‘energy performance gap’ between the calculated and the actual energy consumption levels of buildings, and have explored the reasons for it. The energy performance gap is either caused by calculation drawbacks, uncertainties of modeling weather conditions, construction defects regarding air tightness and insulation levels, or by occupant behavior. This research focuses on the last aspect, i.e. analyzing the relationship between occupant behavior and energy consumption in dwellings, understanding the determinants of energy consumption, and finding occupants’ behavioral patterns. There are several dimensions of occupant behavior and energy consumption of dwellings: dwelling characteristics including the energy and indoor comfort management systems, building envelope, lighting and appliances; occupant characteristics including the social, educational and economical; and actual behavior, including the control of heating, ventilation and lighting of spaces, and appliance use, hot water use, washing, bathing, and cleaning. Attempting to understand this complexity asks for a methodology that covers both quantitative and qualitative methods; and both cross-sectional and longitudinal data collection, working interdisciplinary among the domains of design for sustainability, environmental psychology, and building and design informatics.

Theoretical and experimental thermal performance assessment of an innovative external wall insulation system for social housing retrofit

The UK building stock, being amongst the oldest in the developed world, is also one of the least energy efficient and accounts for approximately 45% of UK carbon emission. Energy use from housing alone was responsible for 13% of total UK carbon dioxide and greenhouse gas emissions in 2015. Therefore, achieving the national target of an 80% reduction in carbon emissions by 2050 against 1990 baseline conditions is highly dependent on the reduction of energy consumption in dwellings. The complexity of the problem of retro-fitting energy saving measures in the extensive and diverse aging housing stock is further compounded due to the number of ‘hard to treat’ properties that comprise over 40% of homes in the UK. In this article, the authors present an evaluation of the theoretical and experimental performances of a novel prototype external wall insulation system, developed to improve energy efficiency in ‘hard to treat’ housing. The system was designed to be primarily used to retrofit social housing, which comprises up to 18% of the current UK housing stock.A thorough testing regime was undertaken to test the suitability and effectiveness of the new product in the most common social housing construction typologies. This included: an investigation of the theoretical thermal performance of the prototype product through steady state modelling, a laboratory based prototype test, an analysis of empirical data collected from a cross section of social housing properties in Nottinghamshire, UK used to inform whole house dynamic modelling, and the development of dynamic simulations to assess the energy and carbon reduction impacts of the new product. The theoretical modelling suggested that the integration of the system resulted in thermal performance improvements for all construction types with space heating demand reduced by up to 42%. The results of the whole house dynamic modelling assessment also suggested that the addition of the system resulted in a reduction of heating energy demand of up to 49%. The prototyping testing shown that the system is easy to install requirement minimum building skills.The findings suggest that the new product not only meets the performance of existing external wall insulation systems, but also provides unique selling points with respect to easy installation and non-reliance on weather conditions. The project finished with a pilot study when one house was retrofitted using the novel product.