Energy Performance Of Dwellings Research Articles

On the relation between architectural considerations and heating energy performance of Turkish residential buildings in Izmir

By considering the energy efficiency legislations among the European Union, Turkey is responsible to provide regulations to comply for the latest European Energy Performance of Buildings Directive 2010/31/EC. New legislation in Turkey requires information about the evaluation of energy performance of existing buildings. This study aimed to determine energy performance of residential buildings in Izmir, regarding significant relationships between their performance and architectural configuration through statistical analysis. The focus was on the heating energy consumption due to Energy Efficiency Law (2007) and Building Energy Performance Regulation (2008), and Standard Assessment Method for Energy Performance of Dwellings (KEP-SDM). This energy performance assessment method was based on Turkish standard TS 825, and European standard EN ISO 13790. It is known that architectural configuration of buildings and design norms have impact on energy performance of buildings. However, emphasis was given on significant values of architectural considerations through certain area-based ratios. The levels of these ratios were matched with the levels of energy consumption. By this, the consideration was to take early-precautions against high energy consumptions in the early design stage and to enhance legislation by adding recommendations of concrete architectural values. These would assist to predict the level of energy performance in the early design phase. Findings would provide feedback information on the residential building stock in İzmir, Turkey.

Thermodynamic efficiency of low-carbon domestic heating systems: heat pumps and micro-cogeneration

Energy and exergy analysis is employed to compare the relative thermodynamic performance of low-carbon domestic energy systems based on air source heat pumps and micro-combined heat and power (cogeneration) units. A wide range of current units are modelled under different operating conditions representative of the United Kingdom to determine the energy and exergy flows from primary energy inputs through to low-carbon heating system and then to end use. The resulting performances are then analysed in order to provide insights regarding the relative merits of the systems under the different operating constraints that may be experienced both now and into the future. Although current mid-range systems achieve comparable performance to a condensing gas boiler, the state-of-art offers considerable improvements. Micro-combined heat and power units and air source heat pumps have the technical potential to improve the energy performance of dwellings. The relative performance and potential of the systems is dominated by the electrical characteristics: the grid electrical generation efficiency, the power-to-heat demand ratio and the availability of electrical export. For total power-to-heat demands below 1:1.5, air source heat pumps have greater improvement potential as their energy efficiency is not constrained. At higher power-to-heat ratios, micro-combined heat and power units offer the potential for higher overall efficiency and this generally occurs irrespective of whether or not the thermal energy from them is used effectively.

Energy policy ambitions and allocation over investment types

Since a few years there is an intensified debate in the Dutch social housing sector about measures to improve the energy efficiency of buildings and individual dwellings. It is generally acknowledged that it is cost-efficient to combine physical measures to improve the energy performance of dwellings with maintenance or improvement activities. Most of these activities take place during void repairs, planned preventive maintenance and renovations. Each can be regarded as an investment opportunity. The allocation of energy improvements between these investment types influences the energy performance of a housing stock in the long term. The central question of this paper is to assess to which extent the energy performance of the Dutch housing stock improves combining these investment types.

Modelling carbon emissions of UK dwellings – The Tarbase Domestic Model

As part of the Tarbase project, the Tarbase Domestic Model was developed to assess the energy performance of dwellings and options for carbon-saving refurbishments. While subject to the usual limits of steady-state building models, the Tarbase model allows the estimation to be tailored to a specific dwelling, with climate and internal activity accounted for. A wider discussion of steady-state models is given, and the application of the Tarbase model to a real case-study of 100 homes is described. The use of such models can be a valuable, and convenient, way of quantifying the approximate performance of a range of individual dwellings, leading the user to solutions for carbon-saving improvements. However, allowing the model to capture the variation in building specification is of great importance, as is the philosophy of seeing the building as being a product of location, construction and activity/operation.

Towards Energy-neutral New Housing Developments. Municipal Climate Governance in The Netherlands

The Dutch government intends to sharpen the current energy performance standard of the national building regulations for new buildings (Energy Performance Coefficient) step by step to an energy-neutral level by 2020. In their climate policies, municipalities are preparing to meet this level for new buildings—some of them even earlier. Nevertheless, possibilities to impose energy performance levels, higher than formulated at national level, are limited for municipalities. This paper investigates, how and through which policy instruments Dutch municipal authorities can promote energy-neutral new housing developments. This research suggests the following municipal climate governance approach and instruments: (1) an integrated design strategy for sustainable energy systems throughout the city: in both urban areas and buildings; (2) market-party-selection in tendering procedures based on sustainability criteria, including the energy performance of dwellings; (3) encouragement of community engagement for the deployment of renewable energy sources; (4) (inter)regional cooperation among cities in similar climatic zones on the development of both more uniform calculation methods for zero-energy buildings, and of a more uniform methodology for cities to monitor progress towards the self-set targets. However, stable and long-term-oriented European and national financial support for municipalities seems to be needed for municipal climate governance to become successful.

Comparison between measured and calculated energy performance for dwellings in a summer dominant environment

The objective of this study is to present a comparison between the measured and the calculated energy performance of dwellings. For this purpose, the energy consumption of ten dwellings is measured for one year. The added value of this work is that it is performed in a summer dominant environment. The energy needs of the same dwellings are also calculated by means of the methodology based on European Standards described in the CEN/TR 15615:2008 technical report. According to the findings of this study, a large gap exists between the calculated and the measured energy consumption of the examined dwellings. In order to evaluate the reasons for this deviation, a detailed analysis of the heating and cooling loads of the dwellings is performed. The intermittent heating of the building is found to be simulated accurately by the employed methodology, whereas the comparison between the calculated and the measured cooling loads reveals a large deviation of about 150%. Based on the findings of this study, a factor of 0.6 should be adopted in the case of cooling schedule, compared to the heating operation of the building.

Behavioural Patterns and User Profiles related to energy consumption for heating

The difference between the actual and predicted energy consumption for heating in housing is thought to be partly attributable to the use of HVAC systems. More reliable data on energy consumption could help in determining the actual energy performance of dwellings and in the search for the most adequate design for housing and home amenities. Further reductions on energy consumption might also be achieved if energy-saving policy programmes were geared to different household groups. The aim of this paper is to statistically determine Behavioural Patterns associated with the energy spent on heating and to identify household and building characteristics that could contribute to the development of energy-User Profiles. This study had two outcomes: it identified Behavioural Patterns to be used in energy calculations and it discerned User Profiles with different behaviours. Five underlying groups of behavioural variables were found, which were used to define the Behavioural Patterns and User Profiles. The groups showed statistically significant differences in the scores for most of the behavioural factors. This study established clear relationships between occupant behaviour and household characteristics. However, it seems difficult to establish relationships between energy consumption and Behavioural Patterns and household groups.

Definition of occupant behaviour patterns with respect to ventilation for apartments from the real estate market in Santiago de Chile

A survey of perception of thermal comfort and occupant behaviour was carried out in Santiago de Chile from December 2009 to January 2010. The survey was applied in an apartment building of the private real estate market. This paper proposes a methodology based on the systematic application of multivariate statistical techniques (principal component analysis, multivariate logistic regression and cluster analysis) which were applied to the collected data of the survey. The results of the statistical analyses show that daytime ventilation is not strongly correlated to the perception of thermal comfort in summer, probably since it is mainly oriented to hygienic purposes. On the contrary, both night ventilation and solar protection appear as very significant predictors for the same dependent variable. The objective of these models corresponds to the definition of occupant behaviour profiles which in combination with meteorological information can be used as input data in energy building simulations. Therefore, these results form a framework that can be implemented to make calculations of energy performance of dwellings more accurate, reliable and representative of the real estate market.

On the Economics of Energy Labels in the Housing Market

The residential housing market can play an important role in the reduction of global carbon emissions, and the information conveyed by energy labels may help to encourage energy conservation among private consumers. This paper reports the first evidence on the market adoption and economic implications of energy performance certificates implemented under a large energy-labeling program in the European Union. The results show that adoption rates are low and declining over time. Labels are clustered among homes and neighborhoods where there is less competition among buyers. We also document that adoption rates of energy labels are positively related to the fraction of ”green” voters during national elections. The energy label seems to create transparency in the energy performance of dwellings and our analysis shows that consumers capitalize this information in the price of their prospective home. The size of the energy-efficiency increment is positively related to the label outcome.

Instrumentation for monitoring energy usage in buildings at Twin Rivers

The measurement systems used at Twin Rivers for determining energy usage are described. These include a weather station, three different systems for the measurement of temperatures and energy-related events in a house, automated devices to measure the air infiltration rate, and infrared thermography. Each of these systems played a role in assessing the actual usage of energy in individual buildings, in identifying the factors that determine energy consumption, and in checking the accuracy of theoretical models for predicting the energy performance of dwellings.