Estimating buildings' energy consumption and energy costs in early project phases

Abstract

PurposeThe purpose of this paper is to show that building stock is currently one of the largest energy consumers. It is thus imperative that buildings are optimally planned, constructed, and used from both the environmental and the economic point of view. Cost models are relevant tools for achieving this objective as they can be used to estimate the occupancy costs in early project phases including energy costs.Design/methodology/approachIn the paper a regression model for predicting the energy consumption and energy costs of office buildings is developed based on the results of a survey conducted in 80 Swiss office properties.FindingsThe proposed energy cost model shows good agreement with the observed field data. The mean absolute percentage error resulted in 12 per cent. Validation tests using five properties not used for the model development revealed percentage errors ranging between −17 per cent and 7 per cent. The proposed concept and the presented cost model can be used as a basis for future studies.Research limitations/implicationsThe energy consumption and energy cost model can be improved as the database for developing them is further extended (including properties from different owners with different strategies, for example energy contracting, outsourcing, and maintenance strategies).Originality/valueThe objective of the study was to develop and validate a predictive model to facilitate the estimation of occupancy costs in early project phases. A procedure is presented on how quantitative energy consumption and cost models can be developed. Provided that sufficient empirical data are available, this proecdure can be used in further studies as a suitable and practicable concept to advance occupancy cost models.