Tese de mestrado integrado, Engenharia da Energia e do Ambiente, Universidade de Lisboa, Faculdade de Ciências, 2017 ; Published works have shown that buildings often consume more energy, than is necessary for occupant comfort. The building sector is accountable for 40% of EU’s final energy use and responsible for 36% of EU’s CO2 emissions, directly related to energy consumption. Researchers say that there is a huge potential for energy savings in this sector, because the available technology is currently highly cost-effective, which could help to mitigate global energy use by the building sector. This study focuses on building performance aspects of an office building at TU/e, such as energy consumption and thermal comfort. EnergyPlus is used as a simulation tool to investigate energy-efficient opportunities, during the later phases of design process, and to research innovative applications for design support. However, buildings do not always perform as well as predicted. This performance gap may result from a number of reasons, but the most representative causes are introduced by uncertainties within the model design. For this reason, in recent years, the calibration of building simulation models has been of growing interest, mostly due to the lack of a recognizable approach to take during the entire calibration process. This paper presents a methodology to apply during model development and calibration optimization, for tuning a set of parameters, while highlighting the effects of uncertainty in the calibration process. The goal is to minimize the difference between predicted (simulated) energy performance and actual measured energy use. To assess the accuracy of the model, two statistical indices are calculated: the Mean Bias Error (MBE) and the Coefficient of Variation of the Root Mean Square Error (CV(RMSE)), which were found to be consistent with ASHRAE guideline 14 limits. After the model has been successfully calibrated and validated, other analyses may proceed. In this research, besides the building’s ...