Future Quarter - Way to an energy-plus quarter in Vienna

With the "Smart City Framework Strategy", the City of Vienna has decided to reduce greenhouse gas emissions by 35% by 2035 and 80% by 2050 per capita compared to 1990. One of the many challenges is the development of sustainable, secure and affordable energy supply strategies for (new) neighbourhoods. The present exploratory study intends to substantially advance the preparation of such a model district with innovative and early energy and economic concepts in the area of research, planning and implementation.

The aim of this exploratory project is the development of transferable concepts for positive energy districts (PED) as a preparation for the implementation of an energy showcase-district in Vienna. Concrete mixed-use areas are addressed in different planning stages, and tailor-made energy concepts and feasibility analyses are developed. The neighbourhoods (mostly new construction sites) differ in terms of renewable energy potential on site, their mix of use and the objectives of the neighbourhood stakeholders.

Method

Through the analysis, modelling and simulation of neighbourhoods, including their technical and economic conditions and the subsequent derivation of recommendations for action (e.g. for the planning process, for technology combinations and for stakeholder integration), the project aims to provide insights into the broader applicability of the "positive energy neighbourhood" concept. Therefore, the following steps were implemented:

• Determination of the expected energy demand of the districts with the passive house project planning package (PHPP) for the expected mixed use (residential, office, retail, ...) and with superstructures in two variants (OIB standard valid from 2021 and passive house construction);
• Potential assessment of the usable solar energy for photovoltaics (PV) in four variants of different size and cost;
• Creation of one conventional and one plus energy concept each, taking into account the local renewable potentials (solar, geothermal, waste heat, air);
• Dynamic energy simulation of demand and coverage, taking into account measures to increase PV own consumption (thermal storage) and the potential of a future renewable volatile electricity supply (wind);
• Estimation of the differential costs for all relevant measures between the two variants for construction, maintenance and operation over a 30-year observation period;

Outcomes

The study of future neighbourhoods shows that positive energy districts can also be implemented in a densely built-up urban context. However, current building regulations need to be superseded and further efficiency measures (e.g. passive house construction) implemented. In addition, the system boundaries should be adapted to enable densely built-up neighbourhoods, which are characterised by efficient use of the valuable estate settlement area, to achieve an energy balance in comparison with lower-density forms of settlement. The remaining energy demand is covered at the annual balance level by the use of predominantly PV and ambient heat. An analysis of the life cycle costs shows that the concepts are cost-effective over a period of 30 years.

Project management

UIV Urban Innovation Vienna GmbH

Project or cooperation partners

• University of Applied Sciences Technikum Vienna
• IBR & I Institute of Building Research & Innovation ZT GmbH

DI (FH) Petra Schöfmann, MSc
Operngasse 17-21
A-1040 Wien
Tel.: +43 (1) 4000 84279
E-mail: schoefmann@urbaninnovation.at
Web: www.urbaninnovation.at