Tracking operational energy performance in existing office buildings

In 2008, the European Energy Performance of Buildings Directive (EPBD) facilitated the introduction of two mandatory energy assessment methods in the UK. Energy Performance Certificates (EPCs) reveal the modelled energy performance of buildings when they are constructed, sold or let based on their intrinsic energy attributes, whereas Display Energy Certificates (DECs) reveal operational energy performance in a subset of buildings that is operated by the public sector, based on annual energy consumption data.EPCs were conceived as a marketing mechanism for property market participants and they have been used in studies that have sought to investigate the links between energy performance and financial performance of buildings. Yet they are based on modelled energy performance and the ratings that they express are hypothetical, whereas DECs are based on actual energy consumption figures. Furthermore, EPCs are valid for 10 years, whereas DECs need to be renewed annually.This study will investigate energy performance patterns as recorded in DEC certificates in existing office buildings over time. The study uses detailed DEC data for commercial office buildings from the Department for Communities and Local Government. This dataset is matched to data on building attributes from CoStar UK to investigate the relationship between energy performance and building features such as age and building quality. This study models the magnitude of observed changes in operational energy performance in existing buildings, to investigate how operational energy performance assessment can be used to track energy performance improvements over time, and reveal how different control variables may impact on recorded changes. These findings will provide further insights into the effects and impacts of the introduction of energy certification for buildings. The further aim of this study is to develop a building typology based on commonly shared building and energy performance attributes.