Grid orientation and natural ventilation in Cerda's 1860 urban plan for Barcelona

The increasing concern about climate change has produced growing interest in natural ventilation and urban planning. There seems to be a gap in the study of introducing urban climate into urban planning, even though doing so would increase population comfort and decrease energy spending. Natural ventilation provided by wind flowing through the streets of a city might be considered as a first priority for passive cooling. It is intuitive that if the street grid coincides with wind flow direction, a city will get more wind in the street. Otherwise, building walls will stop the wind. This study addresses this important topic, grounded on the urbanization of Ildefons Cerdà with regard to Barcelona. In this research, a consistency analysis of the grid orientation and wind flow direction is done for Barcelona. The objective is to demonstrate using current technology that Cerdà’s grid orientation, which strove to capture fresh winds in summer and avoid cold winds in winter, really works. Methodologically, we discuss the reasons, found in the vast work of the Cerdà urban plan, for capturing winds; and we demonstrate the goodness of fit of street grid orientation for capturing winds using spatial analysis in GIS.