Analysis and evaluation of sustainable development of the energy systems in buildings

Cities are very high populated urban areas and consequently very large consumers of finalenergy. Their main characteristic is the largest share in energy consumed by residentialbuilding sector. Therefore, paying attention to the energy use assessment in residentialbuilding sector, at the same time with assessing quality of living, is especially important.Indicators of sustainable development represent essential characteristics for evaluating energyconsumption and living quality in residential buildings.In this paper qualitative characterization of the considered objects is performed based on theperiod of construction (1946-1980 and 1981-2006), type of heating system (electricity,district heating and fossil fuels) and type of object (single family houses and apartments) forthe city of Belgrade. Representative sample was taken into account and, based on thequalitative characterization, divided in nine subgroups (options). Eleven economic, social andenvironmental subindicators were selected and calculated for all chosen options to presentenergy consumption necessary to meet the needs of occupants for space heating, hot waterproduction, cooking, household electrical appliances, indoor air quality, living space, etc.Multicriteria analysis, having application in decision making policies, was used to evaluatesustainability of different residential options through sustainability index calculation. Thismathematical procedure was conducted by agglomeration of normalized subindicators´values into economic, environmental and social indicators (first level) and agglomeration ofindicators into sustainability index (second level).In order to investigate the effect of nonlinearity on the sub-indicators' agglomeration, thechange in nonlinearity was introduced in the procedure. Normalized sub-indicators areobtained by selection of the appropriate linear (θ1= θ2=... =θ11=1) or non-linear parameters(θ1, θ2,..., θ11; θj≠1). Sustainability index and it´s standard deviation were calculated fordifferent values of the parameter θ and each option. The functional dependence between thesustainability index and the associated standard deviation of the θ parameter (characterizingthe way of normalization) was obtained