The New Status Quo
1220 Vienna, Rosthorngasse 5
After the Oskar-Grissemann-Straße 11 and Urschenböckgasse 3 projects, the Rosthorngasse 5 construction project is the third consecutive project in which SÜBA is using renewable energies. As before, the goal is to be fossil-fuel free.
In the current project in the 22nd district of Vienna with 82 residential units, energy from groundwater is used for the first time to enable year-round heat and cold emission in the building. Using concrete core activation, water-filled pipes are installed in concrete ceilings. The high-storage potential in the concrete ceilings are used as a temperature regulator for all apartments in the system with a minimum amount of energy used.
For heating, groundwater is taken from a well system, passes through a heat pump where the heat from the groundwater is transferred, and then returned to another well system with minimal heat loss. With the help of cold groundwater, the entire building is effectively cooled in the warmer, summer months.
Electricity is used to operate the heat pumps. SÜBA strives to delivery this electricity exclusively from renewable energy including hydroelectric, wind, solar, biomass, and regional hydroelectric systems. In order to ensure the delivery of this environmentally friendly electricity, only contracts with Austrian energy service providers are signed who demonstrate a power supply certified with the Austrian environmental label guideline UZ 46 Green Electricity.
Additionally, large-scale photovoltaic systems are installed on the roof of the projects so that the buildings themselves can also be used for sustainable energy production. The electricity is fed into the building’s own heating/cooling system and, in peak summer periods, ensures complete independence from external energy suppliers. In annual operation, the in-house production results in a reduction in the external electricity supply and therefore a further decrease in operating costs for the residents.
2000 Stockerau, centre
The planned project in the heart of Stockerau is worth mentioning. A residential complex with 168 residential units is being built on the property between Hauptstraße, Bahnhofstraße, and Austraße. It consists of six buildings. The structured arrangement of the buildings fits perfectly into the ensemble of the city centre and the entire property is kept free of motorised traffic.
The buildings are to be constructed using a hybrid wood construction method. The load-bearing structure of the building above ground will largely consist of prefabricated wooden elements, which are reflected on the facade and in the interior.
The combination of wood and concrete is a particularly sustainable method – the use of reinforced minimised is minimized, focusing on the wood elements. As wood is a renewable natural resource without any direct fossil energy use, the energy consumption during production proves to be significantly lower than that of steel or brick. Short transport routes of wood from local forests also results in lower emissions. In addition to a healthy indoor climate and optimal humidity, the natural building material contributes to an ideal temperature regulation in both winter and summer.
The entire residential complex is to be heated in winter and cooled in summer by component activation. Instead of groundwater, geo-thermal energy obtained from a deep drilling shaft will be used as an energy source and storage medium – similar to the project in Tulln.
LivingImFranks – Wiener Straße 6–8
The current owner-occupied project LivingImFranks is also equipped with the modern surface heating system called component activation.
Pipes are inserted into the floor ceilings during the construction phase of the building. During operation, hot/cold water flows through the pipes either adding or extracting heat from rooms. The system is therefore equally suitable for both heating and cooling the building.
In this project, the building is supplied with heat via geothermal energy. The heat required to warm the building originates from deep within the ground.
Heat is extracted from the ground via depth probes and made usable by means of a heat pump. The probes used for this are located under the building and extend to a depth of 200 m below the surface of the earth. At this depth, there is a constant temperature of around 10°C to 15°C throughout the year. The heat pump raises the temperature to a higher level in order to make geothermal energy usable for heating.
Just as heat is extracted from the depth probe field in winter, heat can also be dissipated from the building in summer and fed into the ground resulting in the cooling of the interior. Building cooling via geothermal energy is particularly energy-saving because there is no need to operate a heat pump or cooling unit.
The heat is either transferred to or extracted from the apartments via thermally activated reinforced concrete ceilings (component or concrete core activation). The unique properties of this system enable the heat pump system to operate efficiently. A gas condensing boiler is combined with the heat pump for central water heating.
Hot water is generated from cold drinking water via a freshwater station. Therefore, hot water is always available.
The energy concept is complemented by a photovoltaic system on the roof. Green, environmental energy from the public power grid is primarily used for remaining energy requirements.
The building and energy concept of the LivingImFrank property combines diverse technologies to form an intelligent, allencompassing system. It enables a high level of living comfort with low operating costs. A building built for the future.