Impact of Shading Effect from Nearby Buildings on Energy Demand and Load Calculations for Historic City Centres in Central Europe

EU legislation requires introducing a variety of measures to reduce energy consumption. Energy use decrease should be achieved through thermal retrofitting of the least energy-efficient buildings. In the case of cities like Kraków, this means the need to modernize (retrofitting as well as the incorporation of modern HVAC systems) historical buildings. Furthermore, urban morphology is an influencing factor with regards to the energy performance of buildings and therefore of cities (since the influence of shading from nearby buildings cannot be ignored). The paper presents the results of a study on the impact of shading on energy demand for heating and cooling in the historic centre of Krakow. A comparative analysis of the simulation calculation results was performed using the statistical climate as a boundary condition. In the case of a typical five-floor residential tenement house from the turn of the 20th century, an 8% increase in energy demand for heating and a 50% reduction in energy demand for cooling were estimated. As the analysis of the results shows, taking into account the shading from nearby buildings may be crucial for optimizing the volume (power of devices, diameters of ducts and pipes) of the HVAC installation.