9th international conference on energy efficiency in commercial buildings and smart communities
Larger Austrian cities are confronted with the necessity to develop new districts and to revitalise existing neighbourhoods. This process includes the development of new energy supply systems. The conventional solutions usually are gas grids for decentralised use on the one hand and district heating systems on the other hand. But both systems remain unsatisfactory: The simple gas supply is not in line with sustainability and GHG emission reduction goals, whereas district heating (with CHP as major source) is confronted with serious economic problems due to changes at the electricity markets... and municipal utilities thus refuse to enlarge their district heating systems. The paper derives a integrated approach to identify and to evaluate different energy concept options for neighbourhoods. The approach is characterised by the following points of reference: - The (optimised) integration of energy demand and energy supply within the neighbourhood is seen as key success factor. Therefore the characteristics of energy demand are not interpreted as fixed design values but as variable parameter that can be influenced; - The assessment of locally available renewable resources and infrastructures sets the basis for the identification of technically feasible options; - The different technical and energy-economical energy concept options are assessed by means of a life-cycle cost analysis. This approach is widely used at the level of single buildings, but so far not well developed for the district level. This requires methodical adaptations and enhancements. - The same applies for a consistent environmental assessment at the level of districts. Therefore various methodological approaches and performance indicators will be applied. This generic approach was applied in the concept phase of the development of a new neighbourhood in the City of Vienna called Donaufeld. In this feasibility study several technical options for heat supply were developed together with experts within the administration of the city and the local energy supplier Wien Energie. Technical assessment and economical and environmental evaluation of several variants were carried out in order to have a holistic set of criteria as decision support. However, the assessment is not finished yet. The paper can draw preliminary results. Finally, the paper draws conclusions on technical solutions and policy instruments that may be applied to enhance the implementation of sustainable energy concepts in new urban areas.