Urban planning decisions usually have long-term implications that affect both the energy performance, as well as people's experience and the appearance of a city. Once a city or urban quarter is built and problems in these areas start to arise, improvements can often only relieve the symptoms, and rarely address the roots. It is therefore important to address these issues appropriately and early in the planning process. Today's urban design goals often put energy efficiency in the foreground. But energy performance considerations alone do not make livable and sustainable urban environments. In addition to the ecological dimension, sustainable design must likewise consider the social dimension. However, this is often difficult to operationalize, especially in the planning phase, and is consequently not always sufficiently taken into account. In this context, an unsolved problem for sustainable urban planning is to interpret urban structures in terms of their social implications and to systematically evaluate urban design proposals in terms of their social and energy performance related aspects.

In this project we will investigate the relationships between energy performance aspects of urban structures and the perception of a city by its inhabitants. In the first step, our project is focused on the assessment of social and energy performance data of exemplary urban structures in Zurich and Weimar. To this end, we develop methods to firstly measure the emotional impact of spatial structures quantitatively based on empirical studies and secondly to extend the existing computer-based analytical methods to new aspects. For the energy analysis, we draw on existing methods. In the second step, we compare urban structures according to social and energy-related aspects by correlating the empirical data with the results of computer-based analyses. Based on the results of this comparison it is possible to interpret the calculated measures for urban structures in terms of social aspects such as user behavior and perception. In the third step, we draw on this to develop methods to find the best compromise solutions that fulfill social and energy performance aspects equally well. In our study we focus on two central fields of action in urban planning: the definition of street networks and the distribution of building masses, which are collectively referred to as urban morphology.

The results of this project make it possible, using computer-based analysis methods and simple design models, to forecast the social and energy performance implications of planning decisions, and to develop compromises for both dimensions. These planning aspects are crucial to ensure sustainable urban planning as urbanization increases.