An approach to evaluate the energy performance of buildings based on incomplete monthly data
2007 (English)In: Energy and Buildings, ISSN 0378-7788, Vol. 39, no 8, 945-953 p.Article in journal (Refereed) Published
The energy performance of buildings has become increasingly important in the general strive to reduce the overall energy use, which ismanifested in the Energy Performance of Buildings Directive launched by the European Union. An important first step is of course to identify andaddress buildings that have an energy saving potential. In order to achieve this, robust methods for evaluation as well as reliable energy key figuresare needed.For a large majority of multifamily buildings in Sweden the available data of the energy use originates from the property holder. Unfortunately,the data is often limited to the energy that the property holder is responsible for. Thus, information from the tenants about their household electricityuse, indoor temperatures, number of residents, etc., is missing.In this paper an evaluation was conducted on monthly consumption data registered by the property holders for over 100 multifamily buildings/real estates in Sweden. The used approach, based on the energy signature method, was developed for evaluating the energy performance ofmultifamily buildings in terms of the overall heat loss coefficient, Ktot. To compensate for the missing data, different assumed consumption profileshave been used.The results shows that although the obtained value of Ktot for an individual building is rather sensitive to the assumed consumption profiles ofhousehold electricity, the sensitivity is reduced if the evaluation is made in relative and not absolute terms. Thus, the use of consumption profilescould be a successful way to circumvent the present lack of a detailed knowledge of a buildings total energy use. In addition, an evaluation inrelative terms instead of absolute values is also more correct, since available data in almost all cases does not support the determination of the truevalue of Ktot. The use of an average consumption profile instead of a detailed knowledge is of course not desirable, but for fairly large buildings suchan approach could be successful.
Place, publisher, year, edition, pages
2007. Vol. 39, no 8, 945-953 p.
IdentifiersURN: urn:nbn:se:umu:diva-20208DOI: 10.1016/j.enbuild.2006.10.010OAI: oai:DiVA.org:umu-20208DiVA: diva2:208252