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- Danielski, Itai, 1973-
(författare)
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Energy performance of residential buildings : projecting, monitoring and evaluating
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Energy security and climate change mitigation have been discussed in Sweden since the oil crisis in the 1970s. Sweden has since then increased its share of renewable energy resources to reach the highest level among the EU member states, but is still among the countries with the highest primary energy use per capita. Not least because of that, increasing energy efficiency is important and it is part of the Swedish long term environmental objectives. Large potential for improving energy efficiency can be found in the building sector, mainly in the existing building stock but also in new constructions.Buildings hold high costs for construction, service and maintenance. Still, their energy efficiency and thermal performance are rarely validated after construction or renovation. As energy efficiency become an important aspects in building design there is a need for accurate tools for assessing the energy performance both before and after building construction. In this thesis criteria for energy efficiency in new residential buildings are studied. Several building design aspects are discussed with regards to final energy efficiency, energy supply-demand interactions and social aspects. The results of this thesis are based on energy modelling, energy measurements and one questionnaire survey. Several existing residential buildings were used as case studies.The results show that pre-occupancy calculations of specific final energy demand in residential buildings is too rough an indicator to explicitly steer towards lower final energy use in the building sector. Even post occupancy monitoring of specific final energy demand does not always provide a representative image of the energy efficiency of buildings and may result with large variation among buildings with similar thermal efficiency. A post occupancy method of assessing thermal efficiency of building fabrics using thermography is presented. The thermal efficiency of buildings can be increased by design with low shape factor. The shape factor was found to have a significant effect on the final energy demand of buildings and on the use of primary energy. In Nordic climates, atria in multi-storey apartment buildings is a design that have a potential to increase both energy efficiency (by lower shape factor) and enhance social interactions among the occupants.
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| 2. |
- Danielski, Itai, et al.
(författare)
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Adaption of the passive house concept in northern Sweden : a case study of performance
- 2013
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Konferensbidrag (refereegranskat)abstract
- This study analyzes the performance of a case study of low energy house built in Östersund (lat.63°N), Sweden. The building is a semi detached house for two families, with each apartment having afloor space of 160 m2 divided on two floors. The building was constructed during 2010 according tothe Swedish passive house principles with design that meet the requirements for Swedish passivehouses as defined by the Forum for energy efficiency buildings (FEBY) and the Swedish center forzero energy houses (SCNH). The house is connected to the district heating network, which is the mainheat source for domestic water heating, floor heating in the bathroom and water based pre‐heatercoil in the ventilation system. Additionally, a wood stove is installed in the living room for thermalcomfort and convenience of the residents. The two identical residential units in the building wereinhabited in the end of 2010 by families with different characteristics; a family with two youngchildren in one unit and a middle aged couple in the other.A one year energy measurement campaign started in May 2012 for both of the residential units. Themeasurements started after a period of adjustments of the building energy system and include spaceand domestic water heating (separate measurements), household electricity, the amount of fuelwood used in the stove, and indoor thermal conditions. The results show that it is possible to buildpassive houses in the Northern regions of Sweden. The specific final energy demand of the casestudy was 23% lower than the Swedish FEBY‐requirements. Differences were found between themonitored and calculated specific final energy demand. These differences depend to a large extanton the occupants’ behavior and household characteristics. The final energy demand for heating anddomestic water heating found to vary significantly between the two households.
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| 3. |
- Danielski, Itai, 1973-, et al.
(författare)
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Heated atrium in multi-story buildings : A design for better energy efficiency and social interactions
- 2013
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Konferensbidrag (refereegranskat)abstract
- The shape factor of a building expresses the ratio between the building’s thermal envelope area and its volume, or alternatively to its useful floor area. Buildings with lower shape factors will have lower heat losses through the thermal envelope and lower specific final energy demand. The shape factor of building could be reduced by a compact building shape design, and by increasing the volume of the building. However, the requirement for indoor natural light put a limit on the size of the building and therefore may limit the value of the shape factor. One possible solution to address this aspect is designing building with a heated atrium.An atrium is a large enclosed space within a building, and may have a glazed roof. In a multi-story apartment building an atrium has the potential to increase the social interaction between the residents and, with the right design, at the same time reduce the heating demand of the building due to lower building shape factor. However, the use of atrium in residential buildings in Nordic countries has not yet gained popularity.In this paper the impact of the heated atrium building with cylindrical shape design on the specific final energy is investigated by comparing such building design to conventional design buildings with similar floor area. The Nydalahuset project, in city Umeå in the north of Sweden, which is a multi-story residential building with a heated atrium, is used as a case study to investigate the affect of the atrium on the social interaction among the building occupants.The results show that heated atrium building with cylindrical shape design is a better energy efficient design than the conventional buildings. Such buildings in cold climate could help to reduce the heat losses through the thermal envelope and facilitate to achieve the passive house criteria. Moreover, the Nydalahuset project suggests that the atrium design could improve the social interaction of occupants in residential buildings.
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| 4. |
- Danielski, Itai, et al.
(författare)
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Heated atrium in multi-storey apartment buildings : a design for better energy efficiency and social interactions
- 2013
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Ingår i: Passivhus Norden 2013. - : Lågan. ; , s. 76-87
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The shape factor of a building expresses the ratio between the building’s thermal envelope area and its volume, or alternatively to its useful floor area. Buildings with lower shape factors will have lower heat losses through the thermal envelope and lower specific final energy demand. The shape factor of building could be reduced by a compact building shape design, and by increasing the volume of the building. However, the requirement for indoor natural light put a limit on the size of the building and therefore may limit the value of the shape factor. One possible solution to address this aspect is designing building with a heated atrium.An atrium is a large enclosed space within a building, and may have a glazed roof. In a multi-story apartment building an atrium has the potential to increase the social interaction between the residents and, with the right design, at the same time reduce the heating demand of the building due to lower building shape factor. However, the use of atrium in residential buildings in Nordic countries has not yet gained popularity.In this paper the impact of the heated atrium building with cylindrical shape design on the specific final energy is investigated by comparing such building design to conventional design buildings with similar floor area. The Nydalahuset project, in city Umeå in the north of Sweden, which is a multistory residential building with a heated atrium, is used as a case study to investigate the affect of the atrium on the social interaction among the building occupants.The results show that heated atrium building with cylindrical shape design is a better energy efficient design than the conventional buildings. Such buildings in cold climate could help to reduce the heat losses through the thermal envelope and facilitate to achieve the passive house criteria. Moreover, the Nydalahuset project suggests that the atrium design could improve the social interaction of occupants in residential buildings.
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