The primary problems addressed in this action relate to energy demand and emissions from buildings and mobility sectors in urban areas, and the predominantly independent treatment of energy and emissions analyses in those sectors. Buildings and transport systems are closely interconnected. Transport infrastructure and networks play a dominant role in where new buildings are located, while marginal transport costs and transport networks determine the location of demand for residential buildings. Reversing the causality direction, characteristics of the built environment summed up by urban form metrics such as density, distance to centre, land-use diversity etc. are influential on how far and by which mode people travel. These interconnections are intuitive, and have been recognised and studied in scientific fields such as urban economics and planning. However, projections of levels of service, energy demand, and emissions at city, country, or regional scales largely ignore these interconnections as building and transport sectors are modelled independently. The joint production of, and dependence on urban form in building and transport sectors requires much more scrutiny in energy and emission analyses. This is crucial for identifying and prioritising decarbonisation goals, as societies attempt to transition towards low- and zero-emission economies in order to limit the worst effects of climate change.
The overall objectives of SUFFICCS are to bring together analyses of urban form’s influence on service levels (travel demand by mode, and building floorspace), energy, and emissions in transport and buildings sectors, and to estimate the potential for emission reductions through integrated building and transport infrastructure development pathways in European cities.
Conclusions of the action:
This research has investigated and assessed urban form influences on two sectors, mobility, and buildings, in a variety of city types in Western Europe. The main high-level findings are that distance to centre is the primary urban form influence on mobility emissions, and that the single-family share of dwellings is the primary urban form influence on residential floor area per person and residential emissions. In addition, our results support recognition of the high importance of local future population growth as a crucial factor shaping and in some cases limiting the scope of urban development actions to reducing climate impacts. These findings led to a simple urban development scenario generation framework based on three dimensions: population growth, single-family share in new housing, and spatial location of new housing with respect to the city centre. This framework is demonstrated in the results of the research, and it will be extended further beyond the conclusion of the project. Important areas for extension of this research are its application to wider geographical scopes including smaller towns and non-urban areas, and the identification of opportunities to reduce climate impacts in locations with stable population or expected population decline.