Visions of how cities should be built or transformed reflect the diversity of views and perspectives on how people will and should live in cities, since planning in any form always also pursues normative goals. Architecture and urban planning reflect the designs that urban society makes of itself and the conflicts of interest related to the use of cities. Problems of the present tend to concentrate in urban centers, as do experimental solutions to those problems. The built environment, its design and its redesign are themselves becoming objects of the debate over the city of the future.
Climate change is a major problem of the present. It has become common knowledge that the world’s cities account for around 80 percent of all CO2 emissions, and that they conversely offer numerous options to mitigate emissions. Along with industrial production and transportation, buildings are among the most important sources of greenhouse gas emissions. In virtually every corner of the globe, the energy efficiency of existing buildings leaves much to be desired. In Germany, for example, 80 percent of all buildings currently exceed the primary energy consumption ceiling of 70 kWh per m2 per year stipulated in the German Energy Conservation Ordinance (ENeV) of 2007. Yet the standards of the ENeV are not particularly ambitious. If the climate-friendly conversion projects of the KfW development bank were to continue at their current pace, an additional 25 percent of Germany’s residential buildings could be brought up to current energy efficiency standards by 2030. However, private builders in Germany invest several times the total of the funding available from the KfW in residential construction projects without benefiting climate protection. Furthermore, population growth and urbanization is putting considerable pressure on many countries for new residential building – especially the newly-industrialized China and India – and ecological criteria are applied to such construction projects only in exceptional cases. The sustainable city of tomorrow faces not only ecological, but also major social challenges, and these are reasons enough to dedicate a conference and this associated compilation to urban development and urban lifestyles of the future.