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This paper is presented in the context of a gradual move from energy management at a Building level to energy management at Component level. This move requires specific energy consumption and power demand benchmarks to allow measured component energy use and power demands to be put into context. The paper presents a methodology for collecting and collating the data needed for producing these benchmarks from measured operational data. This methodology was tested in the European iSERVcmb project. Example benchmarks from iSERVcmb are provided along with links to the full published data. The paper concludes that large scale measurement and comparison of detailed operational data are possible and useful in support of achieving operationally low energy buildings.Practical application: The explosion of low-cost operational data availability at the level of individual components can be used to improve understanding of their operational energy efficiency in the context of the overall efficiency of a building. The paper shows this data can: Be collected from all types of buildings across all EU Member States Produce benchmark ranges of operational energy consumption and power demands at the level of individual components serving given activities Applying this benchmarked data in the design and operation of buildings will: Improve their operational energy efficiency, Enable legislation using this data to show compliance [ABSTRACT FROM AUTHOR]

This paper describes the development of a spatial database for an annual energy consumption framework. As the database of the existing building stock is a weak point in most European cities but possible pathways to energy reduction in the building sector have to be found, this paper is of high relevance. Our framework uses a complex multi-source data set and a plethora of statistical methods to merge various large complex data sets and then apply a heat balance model in three sub-city areas in Newcastle upon Tyne, United Kingdom. The framework estimates the energy end-use at the single dwelling level on three aggregated scales: district, neighbourhood and communities. We propose a methodology for modelling energy in buildings in different ways depending on the required output scale, the cluster top-down model and the domestic energy model (DEM) bottom-up approaches. The cluster model is a generalization of similar building energy profiles into archetype medoid prototypes in districts and eventually the whole city, whereas the sub-city DEM is a representation of an individual building energy pro- file in neighbourhoods and communities. The framework can be used to test different energy measures (fabric and heating supply systems) for the same property type, and give insights into community energy analysis by aggregating individual building energy consumption. These insights will enable rational and considered responses to be formulated to the problems of integrating renewables into the generation portfolio, that are likely to be faced in the future. [ABSTRACT FROM AUTHOR]

Nowadays, subjects such as eco-design requirements, product rating or code compliance with regard to energy efficiency are expanding towards a pan-European level. This leads to the necessity of defining zones within the European region, which share common climatic characteristics and will further facilitate the quick estimation of building energy performance. Towards this direction stands the current paper; it presents an approach for defining climatic zones in Europe on the basis of the amount of heating and cooling degree days. It is applied for the climate classification of selected European cities and is compared with the conventional scheme based solely on heating degree days. Since the approach is orientated mainly towards the assessment of building energy performance, its outcomes are evaluated with regard to the actual heating and cooling energy needs of a reference building unit with office use located in representative cities of the proposed climatic zones and facing the four cardinal orientations. The classification of climatic zones on the basis of both heating and cooling degree days leads to more realistic results, since nowadays cooling needs form a substantial part of the energy balance of the building, especially in the Mediterranean regions. [ABSTRACT FROM AUTHOR]

Solar heating systems in buildings have increasingly been studied in the past two decades. In several applications the primary energy demand is now for both heating and cooling, and modern solar collectors should be designed to provide climatization during the whole year. Solar systems are seldom applied in Europe, and large buildings, such as office buildings and schools, continue to be built with mechanical ventilation systems.The study presented in this paper is part of a European XVII Thermie project entitled “Pilot project for photovoltaic, energetic and biohousing retrieval in a school”, whose aim was to install a photovoltaic plant and solar air collectors coupled with a sun breaker structure at a scientific high school in Umbertide, in central Italy.This paper describes the research and development activities concerning a solar air collector suited for winter heating and summer ventilation, which was installed at the high school. The collector physical and numerical modelling of heat transfer and fluid flow in winter operation is presented. The system performance has been estimated as a function of different parameters in order to provide a tool for the design process. Furthermore, the climate in the area has been simulated through the available experimental data, and the system behavior under these conditions is presented.The collectors were installed at the scientific high school in Umbertide in spring 2001. Summer ventilation cooling is under testing and an experimental test period is foreseen next winter to validate the design of the collectors and their performance. [Copyright &y& Elsevier]

The need to improve the energy efficiency of buildings has introduced the concept of nearly zero-energy buildings into European energy policies. Moreover, a percentage of the building stock will have to be renovated annually to attain high energy performance. Conventional passive interventions in buildings are focused on increasing the insulation of the building envelope to increase its energy efficiency during the operating phase. Often, however, intervention practices imply the incorporation of embodied energy into the building materials and increase the associated environmental impacts. This paper presents and evaluates a comparison of two different proposals for a real-world building renovation. The first proposal was a conventional project for energy renovation, while the second was a low-energy building proposal (following the Passivhaus standard). This study analysed the proposals using an integrated life cycle and thermal dynamic simulation assessment to identify the adequacy of each renovation alternative regarding the post-renovation energy performance of the building, including an evaluation of the introduction of a renewable insulation material into the low-energy building proposal, specifically a specific cork solution. The most significant conclusion was the convenience of the renovation, achieving energy savings of 60% and 80% for the conventional and Passivhaus renovations (ENERPHIT), respectively. The former supposed less embodied energy and environmental impacts but also generated less energy savings. The latter increased the embodied impacts in the building, mainly for the large amount of insulation material. The environmental implications of both proposals can be compensated for within a reasonable period of time, over 2 years in the majority of alternatives and impact categories. However, the ENERPHIT project was 30% better than the conventional proposal when the total lifespan of the building was considered. The introduction of cork did not fit the requirements for competing with the common non-renewable insulation materials because it did not imply better environmental performance in buildings, but cork insulation solutions currently present ample room for improvement. [ABSTRACT FROM AUTHOR]

Windows are central for the development of liveable nearly zero-energy homes and require careful consideration. Various studies have indicated that the effect of windows on energy consumption may change significantly with improved building insulation levels. Current guidelines on windows may therefore not apply in very well-insulated buildings, and more up-to-date information is needed about window solutions that are appropriate for the new conditions. This study maps the effect of multiple combinations of window size and basic glazing—and frame properties on energy, daylighting and thermal comfort in nearly zero-energy houses located in the European cities Rome and Copenhagen. The aim was to identify options that can support the easy and robust design of future homes with typical use of roof and façade windows. Hourly daylight levels were calculated in DAYSIM, while space heating demand and operative temperatures were calculated in EnergyPlus. The results support previous findings on the limited ability of nearly zero-energy buildings to utilise solar gains. It was found that U -values are becoming increasingly important for the energy performance of windows. The paper sketches the increased flexibility and related possibilities that may appear with improved roof window frame constructions and glazing U -values far lower than currently standard levels. [ABSTRACT FROM AUTHOR]

Abstract: Energy efficiency in buildings is essential for economic, social, and environmental reasons. Under current European legislation, buildings have to be certified with an energy efficiency index. To provide a fair comparison of the energy performance in buildings we need a global and unified representation. In this paper we propose the Energy Efficiency Ontology (EEOnt) to provide a foundation upon which this requirement can be built. EEOnt extends the applicability of other ontological models of buildings incorporating energy efficiency data and knowledge that can be calculated with high spatial and temporal resolution in what we call an Energy Efficiency Landscape (EELB). These EELB''s provide significant information which allows a detailed diagnosis of the energy efficiency within the building. Consequently, EEOnt is capable of representing buildings and energy efficiency in a unified way. Furthermore, it supplies a tool for managing the energy efficiency in buildings and constructing national inventories. These two features link the global and particular needs of governments and users, thus becoming key to both improve the energy efficiency in buildings and to implement viable certification schemes. [Copyright &y& Elsevier]

Abstract: The age of European existing building stock and the very low growth rate make energy retrofit a critical issue at the moment. The spreading of good practices is strongly hampered by their cost effectiveness. National legislation thermal requirements for retrofitting works play a fundamental role. If they are too strict, the initial economic investment could be too high if compared with energy savings achievable. The paper refers to a case study of improving fabric thermal performance of stone masonry buildings located in Cagliari – Italy. They were built in 1950s. The economic feasibility of different energy efficiency retrofits is evaluated. Two different scenarios are analyzed: the former according to the earlier Italian legislation (valid from 2006 to 2008), the latter according to the latest and strictest measures (valid from 2010). The results show that heavy thermal performance upgrades, even though compulsory, are not completely cost-effective in a mild Mediterranean climate area as far as payback time is concerned. National subsidy policies can improve the economic return on the investment. The impact of present Italian incentives has also been evaluated. [Copyright &y& Elsevier]

Abstract: Across Europe domestic electricity consumption is on the rise. In an attempt to counter this increase, various initiatives have been introduced to promote the replacement of less energy-efficient appliances with more efficient ones. Whilst the likely aggregate effect of such measures over long time periods has been modelled extensively, little is known about the affect that a change to higher efficiency appliances will have on the electrical demand profile of individual households at higher temporal resolutions. To address this issue a means by which established approaches to detailed electrical demand modelling can be adapted to simulate the improvements in the efficiency of appliances is elaborated in this paper. A process is developed by which low-resolution empirical appliance demand data can be transformed to produce high-resolution electrical demand data for different periods in the year, factoring in improvements in appliance performance. The process is applied to simulate the effects a changeover to more energy-efficient appliances would have on the minute resolution demand profiles of a group of households. Results indicate that improving the energy-efficiency of appliances in households leads to a significant reduction in electrical energy requirements but does not appear to have a significant affect on the peak electrical demand. [Copyright &y& Elsevier]

The paper considers the European approaches to assessment of the buildings' energy efficiency. We scrutinize their advantages and disadvantages. Specifically, we investigate the feasibility of one of the approaches by employing the example of NTUU "KPI" educational buildings and define principal obstacles that hinder the utilization and can also lead to misinterpretation of the results obtained. We propose possible ways of specification of existing methods and attempt to adapt them to the Ukrainian context. [ABSTRACT FROM AUTHOR]

Abstract: The paper discusses an assessment tool, used for the energy, economic and environmental evaluation of Thermal Insulation Solutions (TIS). The results of the assessment undertaken with this tool can take the form of a simple rating system in order to enable users to perform comprehensive comparisons amongst various building materials and TIS. A ranking expressed by A, B and C classes is used for energy, environmental and economic parameters. By evaluating the materials, the tool supports the users to make decisions, depending on preferences or priorities such as the energy efficiency achieved, the total cost and the environmental performance. The assessment tool is applied for the double cavity wall and the External Thermal Insulation Composite Systems (ETICS) as they are used throughout Europe, both in new constructions and in the renovation of existing buildings. [Copyright &y& Elsevier]

Abstract: Decisions made by architects in the present can influence the global energy, economic and ecological scene for up to a century. Of the annual gross energy consumption 40–50%—and the corresponding emissions—are related to the construction, operation and maintenance of buildings in Europe. The growing concern of professionals and the general public about the role of the building sector in energy use led to national and international legislative measures. The Energy Performance Building Directive (EPBD) by the European Commission lays down a framework for the calculation of the integrated energy performance of buildings. National building regulations based on the EPBD and adapted to the local conditions have to be implemented by 4 January 2006. The EPBD encompasses operational energy only, while other phases of the life cycle of buildings are almost completely neglected. This paper recommends taking into account the energy needed for manufacturing of building materials, the so-called embodied energy, as well, to check the rationality of operational energy saving measures. The significance of embodied energy, the problems of input data and the applicability of discounting techniques are discussed through examples and a method is proposed to account for this type of energy in the regulations. [Copyright &y& Elsevier]

This paper describes the results of the evaluation of a set of retrofitting strategies designed for ten existing office buildings. The work was carried out by the Design and Evaluation Group in the project “OFFICE - Passive Retrofitting of Office Buildings to Improve thier Energy Performance and Indoor Working Conditions” funded by the European Commission under the JOULE III Programme. The objective of the OFFICE project was to promote passive solar and energy efficient retrofitting measures in office buildings. This was done by examining different low energy retrofitting measures in terms of energy, indoor environment, and economy, and by using this as a basis for the development of general retrofitting strategies and design guidelines. The ten European office buildings included in the project are situated in Denmark, England, France, Germany, Greece, Italy, Norway, Sweden, and Switzerland, and the results show that it is possible to significantly reduce the use of purchased energy in existing office buildings in all these countries by using passive and low energy technologies. [Copyright &y& Elsevier]

OFFICE was a research project, partly funded by the CEC, dealing with the passive retrofitting of office buildings to improve their energy performance and indoor working conditions. The project was coordinated by the University of Athens with the participation of organizations and research institutes from eight European countries. The aim of the project was to develop global retrofitting strategies, tools and design guidelines in order to promote successful and cost-effective implementation of passive solar and energy efficient retrofitting measures to office buildings. Within the frame of the project, 10 office buildings located in different climatic zones around Europe were studied extensively. Energy audits and monitoring activities, specific experiments as well as an assessment of the potential of proposed retrofitting scenarios were performed for each building.The final deliverables of the project include: (a) case studies presenting high-quality examples of representative retrofitted office buildings in various parts of Europe; (b) a rating methodology classifying office buildings according to their energy consumption, CO2 production and indoor thermal and visual comfort; (c) an Atlas describing the technical and economical potential for energy conservation of selected retrofitting scenarios for defined types of office buildings in different climatic zones of Europe and (d) Design Guidelines, performance criteria and methodologies for best practice giving credit for renewable energy sources incorporated into office buildings, all presented in the form of a Handbook. Results from the assessment of the potential of various retrofitting scenarios proposed for each case study are included in the Handbook in the form of brochures.This paper gives an analytical description of the activities carried out within the frame of the project and describes the resulting final deliverables. [Copyright &y& Elsevier]

• A new retrofitting strategy by using prefabricated elements window machine. • Minimization of the renovation costs and speeding up the retrofit action. • A potential in energy saving and improving the Indoor Environment Quality. • Further significance in retrofit and healthy home office working environments. The renovation of existing residential buildings across Europe has become a key factor for energy saving and the improvement of Indoor Environment Quality (IEQ). This paper presents an investigation of IEQ for a typical 1960s single-family house in Germany before and after a new retrofitting strategy (prefabricated element with integrated ventilation and new thermal envelope). In-situ measurements were applied to investigate the energy efficiency and IEQ improvement for the new retrofitting strategy in temperate winter regions of Europe. The simulation model replicates the measured data to be closer to reality and simulates a home office (COVID-19) scenario. The in-situ measurements showed that our retrofitting strategy increases the indoor air temperature during the heating period by up to 2.5 °C, decreases relative humidity by up to 3.8% and increases CO 2 by up to 24 ppm than before. As the simulation results shows, the retrofitted home office scenario allows a reduction in heating energy of up to 77%, an increase in CO 2 concentration of up to 41.8 ppm, 0.5% less relative humidity and 1.6 °C higher indoor air temperature than that without retrofitting. The new approach to retrofit residential buildings thus showed a potential in energy saving and improving the IEQ. [ABSTRACT FROM AUTHOR]

Households in Europe are considered to have the largest cost-effective energy-saving potential. This large potential, however, is in the existing residential buildings, and most of these were built before 1950. If serious energy savings are to be met in the near future, it is necessary to carry out intensive renewal of these old buildings. Large investment, however, should include progressive solutions regarding usability and comfort. Also, changes to the buildings should be carried out using sound solutions without the risk of disturbing the moisture balance resulting in mould growth or deterioration. Large-scale renewal for energy saving could be carried out using the technology of custom-made prefabrication already known today. One of the key issues in future energy-saving renewal is accepting changes to the exterior façade of old buildings. [ABSTRACT FROM AUTHOR]