Decision-making method for building energy efficiency retrofit measures based on an improved analytic hierarchy process

Abstract

A large number of building energy efficiency retrofit measures (EERMs) are currently available; however, the ultimate choice of which retrofit measures should be performed is determined by many factors. The aim of this paper is to explore an application of the analytic hierarchy process (AHP) to the selection of EERMs. However, some of the limitations in the current AHP model include a large computational comparison matrix, an incomplete evaluation system, and the difficulty of integrating multidimensional factors. This paper proposes an improved AHP method to overcome these shortcomings. The improvements to the AHP focus on the normalization of the data and the influence of subjective opinions. An evaluation system was built in combination with a life cycle cost analysis. Moreover, a judgment matrix was built from multiple experts through questionnaires and the distributions of the weight factors were calculated. Furthermore, the advantages are discussed through a case study, and the results are compared with other decision-making methods. It was found that the top ranking and less desirable EERMs showed little change when using multicriteria weighted decision-making, but some policy-oriented EERM rankings showed significant changes. The case study indicated that the presented approach significantly simplified complicated multicriteria decision-making problems.