Impact of wind on the energy performance certificates. Case study in Spain

Abstract

The European Union aims to be climate-neutral by 2050. Under the Energy Performance of Buildings Directive (EPBD), Energy Performance Certificates (EPCs) describe both the energy performance of buildings and their associated greenhouse gas emissions. Each Member State should describe its methodology for calculating the energy performance of a building and in Spain, the Technical Building Code (CTE) is used as a reference for outdoor weather conditions. This article compares two weather databases obtained from the CTE and Meteonorm, to specifi-cally evaluate the wind speed and direction data contained. The analysis indicates that the CTE employs identical wind speed and direction for all climatic zones, irrespective of their geo-graphical location. Moreover, significant variations in wind speed and direction within climate zones have been identified when the Meteonorm files were assessed. Additionally, a residential building model was simulated in different scenarios regarding the envelope insulation, climatic zones, fixed and variable convective surface coefficients and weather databases. Based on the results obtained in this study, the use of a fixed or variable convective heat transfer coefficient has minimal impact on the demand values of the building. The main factor contributing to the differences in energy demand is the use of different climate databases. © 2025, Asociación Española de Dirección e Ingeniería de Proyectos (AEIPRO). All rights reserved.