Retrofitting an office building towards a net zero energy building (NZEB)

Energy consumption  in buildings for heating, cooling and lighting needs to be reduced in all European countries in order to achieve the goals set by the latest European Directives  for reducing energy consumption by 20% and increase the introduction of Renewable energy sources by 20%. The present paper focuses initially on the reduction of energy consumption for a university building in Crete and then covering the minimized energy demands with renewable energy sources. The approach is simulation based. At first, current heating and cooling demands of the building are estimated. Subsequently, through the application of basic energy conservation techniques, such as applying cool materials in the façade of the building, a detailed analysis is performed for the energy requirements to cover new demands. Finally, Renewable Energy Sources are implemented in order to provide energy to the building or directly into the grid, thus having a zero energy building.