Methodologies and algorithms for energy and thermal comfort benchmarking, rating and classification of office buildings

Abstract

The aim of this PhD thesis is to develop and propose an integrated classification method for office building sector in Greece. The proposed method includes the building energy performance evaluation method, the building stock database creation, the benchmarking process, the energy boundaries definition and building efficiency improvement methods recommendations. The final scope of this classification scheme is the determination of office buildings’ performance rating boundaries and the establishment of energy and thermal comfort classes at national level. The proposed approach of buildings’ classification includes the following tasks: - The development of a dynamic simulation model to calculate the energy demand for heating and cooling and the thermal comfort conditions of office buildings at an hourly and yearly base. - Energy audits conduction to office buildings in Athens with the aim of buildings’ characteristics investigation and simulation model validation. - The installation of a Building Management System (BMS) in BYTE office building in order to conduct a detailed energy and environmental audit and to use the collected measurements for simulation model validation and improving. - The simulation model generalization and the creation of a virtual building dataset (VBD) for office buildings in Greece. The philosophy of VBD is based on the creation and simulation of random office buildings that could be found or built in Greece, taking into account the Greek constructional and operational characteristics of office buildings and Greek legislation. The VBD consists of 30,000 buildings (10,000 in each Climatic Zone) with their detailed constructional and operational data and of their simulation outputs: the annual energy demand for heating and cooling, the energy consumption for electric lighting and office equipment and an indoor thermal comfort indicator. - The use of VBD data for determining benchmarks such as the Stock Building Reference Value (Rs) and the Regulation Reference Value (Rr) for each climatic zone of Greece, according to the proposed classification by CEN. - The investigation of the application of available clustering techniques, such as Hierarchical, K-Means, Gaussian Mixture Models, Fuzzy and Neural clustering algorithms to the simulated office building dataset towards the establishment of benchmarks and classifications for office buildings in Greece. - The proposal of an integrated classification scheme for Greek office buildings in terms of energy demand and thermal comfort conditions. - The investigation of common buildings’ characteristics (constructional and operational) in each rating class in order to provide with a tool for adopting improvement recommendations for office buildings’ energy efficiency in Greece. - The evaluation of the proposed classification approach through comparisons with methodologies found in literature and mainly with the proposed CEN method, the discussion of the comparative advantages of the proposed scheme and the future work proposals. The results of the present doctoral thesis show that the adopted methodology is an integrated and dynamic classification and rating system for Greek office buildings with the following characteristics: reliability, time saving, low budget processes, large flexibility and expandability and an easy update to the new building data and/or policy decisions.