Retrofitting an office building towards a net zero energy building

Energy consumption in buildings for heating, cooling and lighting is required to be reduced in all European countries in order for the goals set by the latest European Directives for reducing energy consumption by 20% and increasing the introduction of renewable energy sources by 20% to be achieved. The present paper focuses, initially, on the reduction of energy consumption of an office building in the campus of the Technical University of Crete as well as on the cover of minimized energy demands with renewable energy sources. The approach is simulation based. Firstly, the current heating and cooling demands of the building are estimated. Subsequently, some basic energy conservation techniques are applied and a detailed analysis is performed about the new energy requirements. Finally, renewable energy sources are implemented in order to provide energy to the building or directly into the grid, thus having a net zero energy building.