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| 2. |
- Maria, Boman, et al.
(författare)
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The Solar Contribution to the Energy Use for Heating of Residential Buildings
- 2004
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Ingår i: Proceedings of the CIB World Building Congress.
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Konferensbidrag (refereegranskat)abstract
- The energy use of residential buildings in cold and mild climates with the influence of the solar gaincan be simulated with the support of TEKLA 2.0. The model is adjusted to single-zone buildings thathave a uniform internal temperature. The calculations are based on the standard EN 832, whichincorporates dated or undated references and provisions from other publications. The predicted resultscorrespond well with the measured data from a monitored occupied residential reference building InUmeå, Sweden.A parameter study was made with TEKLA 2.0 on simulated data of the reference building for climateconditions in Umeå, Kiruna and Lund, Sweden. It indicates that the parameters that have the mostinfluence on the thermal performance of the building according to the components are the U-value ofthe wall, the thickness of roof insulation and the U-value of windows. The parameters that have themost influence on the solar gain are the daily average global solar radiation and the directions of thewindows provided.
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| 3. |
- Meier, Alan, et al.
(författare)
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What is an energy efficient building
- 2002
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Ingår i: ENTAC 2002 - IX Meeting of technology in the built environment. ; , s. 3-12
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Konferensbidrag (refereegranskat)abstract
- Proposed regulations in Brazil call for minimum energy efficiencies in building design and appliance manufacture. These regulations are expected to translate into lower operating costs for the occupants, reduced energy demand for the utilities, and potentially lower carbon emissions for the country. The concept of “energy efficient” buildings has immediate implications on regulations, economics, energy demand, and the environment. A definition is also needed to compare building energy performance or to assess absolute energy efficiency. We propose three criteria for an energy efficient building: 1) the building must be equipped with efficient equipment and materials appropriate for the location and conditions; 2) the building must provide amenities and services appropriate to the building’s intended use; and 3) the building must be operated in such a manner as to have a low energy use compared to other, similar buildings. An efficient building must, at a minimum, be above average in all three aspects. When setting minimum efficiency standards, a definition of energy efficiency based on minimum life cycle costs is likely to result in much stricter standards—and greater energy savings—than a strategy based on eliminating the least efficient units.
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| 5. |
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| 6. |
- Olofsson, Thomas, 1968-, et al.
(författare)
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Long term energy demand predictions for buildings based on short-term measured data
- 2001
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Ingår i: Energy and Buildings. - 0378-7788 .- 1872-6178. ; 33:2, s. 85-91
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Tidskriftsartikel (refereegranskat)abstract
- In order to obtain long-term predictions based on short-term data, a neural network model was developed. The model parameters are indoor and outdoor temperature difference and energy for heating and internal use. For purposes of training the neural network model a method for extending the measured data to represent an annual variation is proposed. The method has been applied on six single-family buildings. Based on access to data from 2 to 5 weeks, the deviation between predicted and measured diurnal energy demand on an annual basis was about 4% with a correlation of 90–95%, when access to the indoor and outdoor temperature difference was assumed. For models based on access to data from the warmest periods with a very small heating demand, the deviation was about 2–4 times larger.
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| 7. |
- Olofsson, Thomas, 1968-, et al.
(författare)
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Multivariate Methods for Evaluating Building Energy Efficiency
- 2004
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Ingår i: Proceedings of the 2004 ACEEE Summer Study of Energy Efficiency in Buildings. - 0918249538 ; , s. 265-274
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Konferensbidrag (refereegranskat)abstract
- For an owner or operator of a building, benchmarking can be a useful guide for finding outhow energy efficient the building is and identifying what to improve. For successfulevaluation of the building energy efficiency, the categorization as well as the parameteridentification has decisive importance. That selection can be based on mathematical modelingsuch as linear regression accompanied with more or less user expert knowledge. Theselection, however, is not a simple task since analyses based on statistical data are sensitive tocorrelations between different measured parameters. For improving that analysis multivariatemethods such as Principal Component Analysis (PCA) can be a valuable support.We demonstrate here how PCA can be a useful tool for investigating aggregated statisticaldatasets. The investigation illustrates how a set of building performance parameters exhibitsdifferent relations depending on how the categorization is made, which is relevant to considerwhen benchmarking. The study is based on a national Swedish database of aggregated energyuse and building performance statistics.
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| 8. |
- Olofsson, Thomas, 1968-, et al.
(författare)
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Overall heat loss coefficient and domestic energy gain factor for single family buildings
- 2002
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Ingår i: Energy and Buildings. - 0378-7788 .- 1872-6178. ; 37:11, s. 1019-1026
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Tidskriftsartikel (refereegranskat)abstract
- In this work we introduce a method for estimating the variation of the overall heat loss coe"cient and the domestic energy gain factor. Based on a neural network model, these parameters were extracted from analyzing the model by indirect methods. The used model parameters were: the supplied heating demand, the domestic electrical demand and the indoor–outdoor temperature di5erence. A feed-forward back propagation neural network was used as modeling tool. The proposed method has been found accurate, based on an analysis of arti6cially generated data. Additionally, measured data of inhabited single family buildings were examined and the model was found to generate reliable results, in parity with results obtained by comparable methods and estimations.
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| 9. |
- Olofsson, Thomas, 1968-, et al.
(författare)
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Rating the Energy Performance of Buildings
- 2004
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Ingår i: The International Journal of Low Energy and Sustainable Buildings. - 1403-2147. ; 3
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Tidskriftsartikel (refereegranskat)abstract
- In order to succeed in developing a more sustainable society, buildings will need to becontinuously improved. This paper discusses how to rate the energy performance of buildings.A brief review of recent approaches to energy rating is presented. It illustrates that there is no single correct orwrong concept, but one needs to be aware of the relative impact of the strategies. Different strategies of settingenergy efficiency standards are discussed and the advantages of the minimum life cycle cost are shown.Indicators for building energy rating based on simulations, aggregated statistics and expert knowledge arediscussed and illustrated in order to demonstrate strengths and weaknesses of each approach. In addition, theimportance of considering the level of amenities offered is presented.Attributes of a rating procedure based on three
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| 10. |
- Sjösten, Jerry, et al.
(författare)
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Heating energy use simulations for residential buildings
- 2003
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Ingår i: Eight IBPSA conference and exhibition, building simulation. ; , s. 1221-1226
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Konferensbidrag (refereegranskat)abstract
- In this paper, we present a new simulation program, TEKLA, for estimating energy use of residential buildings according to the European standard, EN832. The simulation program is written in MATLAB 6.2. The focus is to estimate variations of significant parameters influencing the energy use of the building. TEKLA can be used in design of new and retrofitted energy-efficient buildings. The model predictions are in good agreement with monitored data from an occupied residential building located in Umeå in northern Sweden.
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