Energy Consumption In Houses Research Articles

Building Energy Assessment and Computer Simulation Applied to Social Housing in Spain

The actual energy consumption and simulated energy performance of a building usually differ. This gap widens in social housing, owing to the characteristics of these buildings and the consumption patterns of economically vulnerable households affected by energy poverty. The aim of this work is to characterise the energy poverty of the households that are representative of those residing in social housing, specifically in blocks of apartments in Southern Europe. The main variables that affect energy consumption and costs are analysed, and the models developed for software energy-performance simulations (which are applied to predict energy consumption in social housing) are validated against actual energy-consumption values. The results demonstrate that this type of household usually lives in surroundings at a temperature below the average thermal comfort level. We have taken into account that a standard thermal comfort level may lead to significant differences between computer-aided energy building simulation and actual consumption data (which are 40–140% lower than simulated consumption). This fact is of integral importance, as we use computer simulation to predict building energy performance in social housing.

Initiatives for the energy renovation of single-family houses in Denmark evaluated on the basis of barriers and motivators

The renovation of single-family houses in Denmark is progressing only slowly. Changes in current policy are needed if the political goal of a fossil-free building sector as part of a fossil-free society is to be achieved. Known barriers and motivators for energy renovation are identified, and arranged in a framework with three main fields (Information, Finance and Process), with a total of 14 sub-areas. With this framework, current Danish policy is analysed to identify shortcomings, found to mainly exist in connection with financing and decision support. Using experience from other countries, suggestions are made for improvement in four areas: (1) focus on non-energy benefits rather than investment, (2) enhancement of subsidy system, (3) including relevant renovation plans in the energy performance certificate (EPC), and (4) long-term regulation on the maximum allowed energy consumption of houses.

Are Green Buildings Really 'Greener'? Energy Efficiency of Green Mark Certified Buildings in Singapore

There is no conclusive evidence in the existing literature to show that green buildings save more energy than conventional buildings. Why do buyers pay premiums for green buildings? This study empirically examines whether the “Green Mark” (GM) certification is either a signal for energy efficiency in buildings or a reputational signal segregating developers in the pooling equilibrium. Using a unique panel of electricity consumption data for a large sample of residential buildings in Singapore, we do not find significant differences in energy consumptions between GM-certified buildings and non-GM-certified buildings, on the days when the sky is shrouded by strong haze and the energy consumption in the buildings is relatively high. However, we find that the average transaction price of GM-certified dwellings is 1.61% higher than that of the comparable not GM-certified dwellings. With a difference-in-difference approach, we show significant and positive GM labeling announcement effects on housing prices and energy consumption. An instrumental variable approach is employed to deal with potential omitted variable bias and reverse causality issues between energy consumption and housing prices and to determine whether green housing is a sound investment that leads to intangible returns. The 2SLS estimates indicate that electricity consumption has no effect on housing prices implying that green housing premiums may not be as valuable without providing the expected energy savings.

寒冷地における住宅の一次エネルギー消費量の比較に関する研究 その1 電気・ガス併用住宅と全電化住宅の一次エネルギー消費量の比較

寒冷地における住宅の一次エネルギー消費量の比較に関する研究 その1 電気・ガス併用住宅と全電化住宅の一次エネルギー消費量の比較

寒冷地における住宅の一次エネルギー消費量の比較に関する研究 その2 PEFC-CGS設置住宅と潜熱回収型ガス給湯器設置住宅の一次エネルギー消費量の比較

寒冷地における住宅の一次エネルギー消費量の比較に関する研究 その2 PEFC-CGS設置住宅と潜熱回収型ガス給湯器設置住宅の一次エネルギー消費量の比較

Waste management studies in a Brazilian microregion: GHG emissions balance and LFG energy project economic feasibility analysis

The appropriate management of municipal solid waste (MSW) is a key issue in today's economy. In Brazil, this has been the subject matter of several studies, since the National Policy on Solid Waste in 2010 established the closure of dumps and encourages the implementation of more appropriate forms of MSW disposal. In order to contribute to the study of MSW management in Brazil, this paper presents a two-step analysis of the MSW management of São Lourenço microregion consortium (MG). In the first step, WARM (USEPA) software was applied in evaluating Green House Gases (GHG) emissions and energy consumption at three alternative scenarios, which were compared to a baseline scenario, where all MSW was sent to landfills. Scenario 1: Reprocessing of all recyclable waste and composting of organic fraction of MSW. Scenario 2: Reprocessing of all recyclable waste but with an organic fraction of MSW landfilling and scenario 3: Incineration of all solid waste. At the second step, the economic feasibility of a project to generate energy from the landfill biogas (LFG) was evaluated in terms of GHG emissions. The most advantageous alternative was scenario 1 because it allowed the reduction up to 90,000 tCeq in relation to the base scenario of MSW management. The economic feasibility of generating energy from LFG was only achieved for the scenarios in which the enterprise was considered as a form of microgeneration as regulated by the National Agency of Electric Energy (ANEEL, in Portuguese), which indicates the need for government incentives so as to reduce the costs of such projects and the need to incorporate new cities into the consortium analyzed, thereby expanding the mass of waste available and also increasing the production of landfill gas.

Possible explanations for the gap between calculated and measured energy consumption of new houses

The overall aim to reduce CO2 emissions has brought the energy requirements for new houses into focus. The question is whether the stepwise tightening of the energy requirements for new houses has had the expected impact on the actual realized energy consumption. In the news media, headlines at regular intervals state that new houses do not perform as expected with regard to energy consumption based on a simple comparison to the building class (energy frame). The gap is sometimes explained by a higher indoor temperature than used in the standard calculation or more generally by resident’s “careless” energy behavior. However, this may not be the full explanation and there may be other reasons for the difference. Or more specifically: Does the theoretical calculated energy demand, based on standard assumptions and without taking into account the effect of variations in e.g. hot water consumption, internal heat gains or construction faults, underestimate the actual energy consumption in general? As an example, the registered measured energy consumption for heating and hot water of approximately 800 new houses was compared to the calculated energy demand. The analyzed energy consumption data show that a significant share of the houses consumes more energy in a simple comparison with the theoretical energy frame based on standard assumptions. The objective of the study was to find and evaluate possible explanations/reasons for this gap between the theoretical calculated energy demand based on standard assumptions and the real-life registered measured energy consumption for new houses. It includes an evaluation of the possible impact on the energy demand caused by deviations from the standard assumptions for a series of parameters like indoor temperature, hot water consumption, internal heat gains, U-values, thermal bridges and ventilation rates.

Carbon footprint trends of metropolitan residents in Finland: How strong mitigation policies affect different urban zones

Around the world, cities are creating local climate change mitigation strategies and combining strengths in international efforts. In addition to making the strategies, it is important to follow, how they work in practice. The aim of the study is to examine, how climate change mitigation policies and other events affected the consumption-based household carbon footprints in the Helsinki Metropolitan Area (HMA) from 2006 until 2012. The cities of the HMA launched an ambitious climate change mitigation strategy in 2007. Furthermore, the study analyses the changes in the carbon footprints of six different types of urban zone within the HMA: the central pedestrian zone, the fringe of the central pedestrian zone, intensive public transport zone, public transport zone, car zone and the pedestrian zones of subcentres. The results of the study reveal that the average carbon footprint decreased 7% from 2006 to 2012, despite 1% increase in expenditure, which is encouraging. Emissions caused by housing energy consumption and motor fuel consumption decreased the most. Among the urban zones, public transport zone and car zone, which are the two outermost zones of the HMA, had the strongest emission reductions. Cleaner electricity and the improved energy efficiency of buildings had a strong effect. The regression analysis of the study suggests that the central pedestrian zone and the car zone, the two most affluent zones of the HMA, have higher carbon footprints than all the other zones have between them. However, this is only true when income is controlled, not when expenditure is controlled. The economic crisis in 2008, and changes in consumption behaviour because of it, seem to explain the result. The reduction of the average carbon footprint in the HMA was not only due to steered mitigation actions. Increased housing costs seem to have contributed to the decline of consumption-based emissions. The results of the study suggest that to achieve the ambitious international, national and local climate change mitigation targets, stronger measures are needed.

Prospective modelling of the hourly response of local renewable energy sources to the residential energy demand in a mixed urban-rural territory

This paper presents a new bottom-up model used to evaluate the potential response of local renewable energy sources (RES) to the residential demand of a territory involved in a 100% RES process. It estimates housing energy consumption hour-by-hour using archetypes and GIS data combined with statistical data available nationwide. Residential load profiles were calculated at IRIS scale on a mixed urban-rural French territory for year 2015 and validated with national reference data.Local renewable energy potential was estimated and a production model was developed to calculate hourly production profiles. Prospective scenarios were defined at horizon 2050 to compare the impacts on energy demand of trend evolution to voluntarist energy transition scheme. For each demand scenario, an optimal production mix was found to maximize the dynamic cover of the demand. The analysis of these consumption-production pairs highlighted issues of energy transition in both residential sector and local renewable energy production.

A-40 寒冷地域の集合住宅における温熱環境とエネルギー消費に関する研究 : その3.排気型セントラル換気システムの効果

A-40 寒冷地域の集合住宅における温熱環境とエネルギー消費に関する研究 : その3.排気型セントラル換気システムの効果

B-58 住宅における暖房エネルギー使用と室内温湿度環境に関する実態調査

B-58 住宅における暖房エネルギー使用と室内温湿度環境に関する実態調査

Minimizing the energy consumption of low income multiple housing using a holistic approach

The present paper describes a holistic energy efficient retrofit of low income multiple social housing located in Athens, Greece. A holistic analysis was conducted in order to determine the optimum retrofit plan that includes innovative and state of the art commercially available technologies, passive techniques as well as renewable energy sources, aiming to reduce its energy consumption and carbon footprint, improve indoor environmental conditions and be cost effective at the same time. An extensive experimental campaign including air leakage measurements, thermal imaging, energy consumption and indoor environmental quality measurements was conducted before and after the implementation of the retrofit. In addition, advanced building simulation, occupant surveys and socioeconomic analyses were performed in order to evaluate the impact of the retrofit and estimate specific performance indicators.

Understanding comfort and senses in social practice theory: Insights from a Danish field study

Thermal comfort is central to energy consumption in housing and one of the main drivers behind worldwide GHG emissions. Research on residential energy consumption has therefore addressed comfort in relation to indoor temperatures. This paper argues that by widening the focus of comfort to include other aspects such as air, light and materials, more sustainable ideas of residential comfort might be developed. The paper takes a practice theoretical perspective but argues that the senses should be better incorporated into the approach to understand different aspects of comfort. The paper investigates how comfort can be understood as sensorial within theories of practice. This implies understanding how the senses are incorporated in embodied and routinised social practices, through which comfort is sensed and interpreted. Comfort is related to a range of everyday practices in the home, and the paper describes how aspects of comfort are perceived differently within different practices. The study is based on qualitative interview data from a Danish field study. However, the findings on how comfort in houses can be understood have a broader relevance as well. It is argued that this nuanced perspective on comfort can contribute to widening the debate and policy on residential energy consumption.

Heuristic approaches for a domestic energy management system

In the context of smart buildings, house energy consumption plays a significant role in the energy system. Since there are different billing rates, the aim of the smart grid system is to minimize the overall energy cost by appropriately selecting the best starting times for each household appliance. Further, the scheduler should guarantee that the instant energy request does not overcome the maximum threshold which depends on the customers contract.Although the maximum threshold is a constant, the instant energy consumption may possibly exceed this value, whenever is available some renewable source such as, for instance, solar energy. In this work, we consider the problem of scheduling smart home appliances within a given time horizon respecting the threshold on the energy peak consumption with the objective of minimizing the overall cost related to the average energy consumption of each appliance at each time instant. A hybrid heuristic based on a mixed integer programming formulation of the problem and a particle swarm optimization approach are proposed. Computational results, applying these approaches to real life data are provided and discussed.

Climate Change Adaptation Pathways for Residential Buildings in Southern China

Abstract China Building energy consumption contributes about 30% to the total national greenhouse-gas (GHG) emissions, and thus, to climate change. At the same time, climate change will in turn impact the total energy consumption and GHG emissions of residential sector. This study investigated the potential impact of climate change on the total energy consumption and related GHG emissions of housing in Southern China. Identified potential pathways were implemented for existing and new residential buildings to adapt to climate change. Results show that the ambient temperatures in 2020s, 2050s and 2080s will increase by 0.82 oC, 1.91 oC and 3.41 oC accordingly. The total heating and cooling energy use of 3.5 and 5.5 star-buildings are projected to increase 25% and 20% respectively with a 1.0 oC global warming. However, utilizing energy-efficient appliances and retrofitting the house to 6.5 stars or higher level are substantial measures to maintain the level same as or less than the current level of overall energy consumption and GHG emissions. Climate adaptions that focus on improving the energy-efficiency of building envelop, applying renewable energy and switching to facilities with low GHG emissions are desirable solutions.

Application of life cycle assessment approach to deliver low carbon houses at regional level in Western Australia

Australian building sector contributes 23% of the total greenhouse gas (GHG) emissions. This is particularly important for Western Australia (WA) as the houses here are made of energy- and carbon-intensive clay bricks. This research has utilized life cycle assessment (LCA) approach and cleaner production strategies (CPS) to design low-carbon houses in 18 locations in regional WA. An integrative LCA analysis of clay brick house has been conducted by incorporating energy efficiency rating tool (i.e., AccuRate) to capture the regional variation in thermal performance of houses in 18 locations in WA under five climatic zones. The data bank provided information on energy and materials for mining to material production, transportation of construction materials to the site of construction, and construction stages, while an energy rating tool has been utilized to generate location-specific information on energy consumption during use stage for developing a life cycle inventory for estimating life cycle GHG emissions and embodied energy consumption of a typical 4 × 2 × 2 detached house (i.e., 4 bed rooms, 2 bathrooms, and 2 cars/double garage). This approach has enabled us to determine the location-specific hotspot of a house in order to select suitable CPS for achieving reduced level of GHG emissions and embodied energy consumption. Except for two hottest locations, the average life cycle GHG emissions and embodied energy consumption of houses at 16 locations in regional WA have been estimated to be 469 t of CO2 equivalent (or CO2 e-) and 6.9 TJ, respectively. Home appliances and water heating have been found to be the top two hotspots. The CPS options, including rooftop solar photovoltaic panels (PV), solar water heaters (SWH) integrated with gas based water heaters, cast in situ concrete sandwich wall, fly ash as a partial replacement of cement in concrete, and polyethylene terephthalate (PET) foam made of post-consumed polyethylene terephthalate bottles, have been considered to reduce GHG emissions and embodied energy consumption of a typical house in18 locations in regional WA. Excluding above two hottest locations, these CPS provide an opportunity to reduce GHG emissions and embodied energy consumption per house by an average value of 320 t CO2 e- and 3.7 TJ, respectively. Considering the alarming growth rate of the housing industry in WA, the incorporation of optimum house orientation, rooftop solar PV, roof top SWH, cast in situ sandwich wall, partial replacement of cement in concrete with fly ash, and PET foam insulation core could reduce the overall GHG emissions and embodied energy consumption associated with the construction and use of clay brick wall house which in turn will assist in achieving Australia’s GHG emission reduction target by 2050. The findings provide useful data for architects, designers, developers, and policy makers to choose from these CPS options based on existing resource availability and cost constraints.

Effects of Urbanization on Rural Drinking Water Quality in Beijing, China

Urbanization is an inevitable trend in historical development, but eco-environmental problems, including drinking water safety, have gradually become more and more outstanding during the process of rural urbanization. Ten districts in rural areas of Beijing, China were selected to study the effects of urbanization on drinking water quality. The relation between the urbanization index and drinking water quality indicators were explored. The influence of the urbanization process on drinking water quality showed that housing construction, population urbanization, energy consumption, and industrialization during urban development were closely related to drinking water quality. The paired t-test showed the total electricity consumption, living electricity consumption, tertiary industry, and the GDP growth rate had boundary (p = 0.06) or significantly positive (p < 0.05) relations with the qualified rate of rural drinking water. The grey correlation analysis showed that the growth rates of the value-added of housing construction areas were the most important factor affecting comprehensive water quality of Beijing rural areas, followed by the growth rates of the value-added by secondary industry and total electricity consumption, and then the growth rates of the value-added by the tertiary industry and GDP. Urbanization had a significant impact on individual water quality indicators. The results of this study provided some supports for drinking water security in the face of urbanization.

Solar Town Fuchu – Plan and Performance

Tokyo Metropolitan Government planned a residential area with sixteen high-performance solar houses, for the purpose of reducing carbon dioxide emitted from houses in Tokyo. We collected data on energy consumption and room temperature for two and a half years and conducted a questionnaire survey on the awareness and lifestyle of the residents to investigate the performance of the houses. As a result, it was found that the energy consumption of solar houses is about half of the ordinary houses and the carbon dioxide emissions is over 75% lesser than the ordinary houses considering the contribution of PV generation sold. Also the issues for zero energy houses (ZEH) are clarified based on the characteristics of each type of house.

An investigation of the Performance of a Conical Solar Water Heater in the Kingdom of Bahrain

Domestic water heater corresponds to 25% of the house energy consumption and can play an important role to reduce energy house expenses. Solar energy offers a preferred renewable energy resource because of its economic and environmental advantages. It is considered the best alternative to reduce domestic water heater energy consumption cost. Converting solar energy into heat can be considered among the simplest used systems. Solar thermal conversion is more efficient than solar electrical direct conversion method. Solar water heater systems are particularly easy to use and to repair. The integrated conical solar collector water heater (ICSCWH) is so far the easiest among water heating systems. The ICSCWH converts directly and efficiently the solar flux into heat. In order to expand the utilization of ICSCWH systems, many design modifications have been examined and analyzed. This study provides an experimental investigation and mathematical simulation of an ICSCWH system equipped with a glass cover resulting in the increase of the maximum absorption. Integrating the cone-shaped heat collector with an aluminum spiral pipe flow system may enhance the efficiency of the proposed system. In order to maximize the solar radiation of the system, the solar water heater has been designed in a conical shape, which removes the need to change its orientation toward the sun to receive the maximum sun radiation during the day. In this system, the heating of water has been obtained using the spiral pipe flow without the use of the solar cells and mirrors in order to reduce the total cost. The storage water tank of this system is coupled with a conical solar collector. Based on the above design, the solar water heater has been fabricated and tested. In addition, an analytical modeling approach aiming to predict the flow rate within the conical integrated collector storage solar water heater (ICSSWH) and its efficiency, was developed. Modeling through a numerical simulation approach based on energy equations was performed. Considering the entire water amount and the total area of the cone, the amount of water (facing the sun per unit absorbing area in the two symmetrical parts of the system) is found to increase, which is expected to reach a maximum water temperature at a high performance. Our experimental findings show that the daily performance is around 32% and the highest water temperature of about 45°C is obtained in the system at 4 pm, according to seasons and weather conditions. An efficient and simple mathematical simulation approach for the new conical solar water heater is described then validates using experimental data.

Prediction of residential building energy consumption: A neural network approach

Some of the challenges to predict energy utilization has gained recognition in the residential sector due to the significant energy consumption in recent decades. However, the modeling of residential building energy consumption is still underdeveloped for optimal and robust solutions while this research area has become of greater relevance with significant advances in computation and simulation. Such advances include the advent of artificial intelligence research in statistical model development. Artificial neural network has emerged as a key method to address the issue of nonlinearity of building energy data and the robust calculation of large and dynamic data. The development and validation of such models on one of the TxAIRE Research houses has been demonstrated in this paper. The TxAIRE houses have been designed to serve as realistic test facilities for demonstrating new technologies. The input variables used from the house data include number of days, outdoor temperature and solar radiation while the output variables are house and heat pump energy consumption. The models based on Levenberg-Marquardt and OWO-Newton algorithms had promising results of coefficients of determination within 0.87–0.91, which is comparable to prior literature. Further work will be explored to develop a robust model for residential building application.