tz1, the first building at the Technology Centre Seestadt produces more electricity in full operation than it uses. However, an array of measures are needed to actually achieve this energy plus standard.
Highly efficient and tight building envelope: a highly thermally insulated façade with an all-round and external sun protection. In this way, as little heat as possible is brought into the building in summer, and in winter the optimal thermal insulation ensures low losses.
Systematic data collection and precision control of the existing technologies and Systems.
The 1,300 m² photovoltaic system in combination with an automated heating and cooling system, via building component activation and ventilation, eliminates the need for radiators.
Optimum use of daylight, a shading system that tracks the angle of the sun, and a highly efficient ventilation system that measures indoor air quality using CO2 sensors to determine occupancy density create an ideal indoor and working climate.
Highly efficient heat recovery from the ventilation system and groundwater and use of waste heat from server rooms. This already achieves a high proportion of the energy requirement for heat and humidity.
Use of a recooler on the roof in the transitional periods as a free cooling system.
The PVC-free, eco-friendly concrete used in the facility generated 80 per cent lower CO2 emissions during the manufacturing process.
Award-Winning Technology Center
The 6,600 m² building has received gold certification in accordance with the guidelines of Klimaaktiv (1,000 out of 1,000 points) and TQB certification for service buildings (977 out of 1,000 points) from the Austrian Sustainable Building Council (ÖGNB). In 2014, the impulse project of Aspern – Vienna’s Urban Lakeside received the Green Building Integrated Design Award.
An array of technical measures have turned the dream of a positive annual energy balance into reality.
Ventilation and deaeration according to demand
The building is equipped with a unique ventilation system that is controlled based on the outside temperature. Common areas are naturally ventilated in spring and autumn, thus saving much of the energy that is used by mechanical ventilation systems in passive-energy buildings. The integration of CO2 sensors and corresponding control baffles in the ventilation system and the optimum positioning of the ventilation shafts are also crucial for minimising energy consumption. Great importance was also placed on the energy-efficient conditioning of the fresh air supplied to the building through the ventilation system. A full 90% of the total requirement can be met by the rotary heat exchangers and the heat and moisture they recover.
Optimised use of daylight and energy-efficient artificial lighting
The innovative lighting concept combines the optimised use of daylight with energy-saving artificial lighting. Floor to ceiling window constructions as well as outdoor shades designed to make use of natural light ensure that workspaces are optimally supplied with sunlight. Artificial lighting is provided throughout the building by floor lamps with occupancy and daylight sensors that significantly reduce power needs. This reduces the connected load by 50% compared with conventional floor lamps. The shading system on the building exterior is controlled by a sensor on the roof that measures the sun's position and intensity and that uses this data to automatically adjust the sun shades.
Heating and Cooling
The office spaces are heated and cooled using concrete core activation. For cooling purposes, a combination of water circulating through the structural element and the outdoor temperature level is used. This significantly reduces the amount of energy used for the site in comparison with conventional cooling technologies. The system switches automatically between the groundwater system and the free-cooling system when the outdoor temperature reaches 15° Celsius. Once this temperature is reached, the free cooling system is more efficient; to cover peak loads, additional use is made of the district heating system.
The 1,300 m² photovoltaic system is the technical highlight and consists of several elements. The first key element is located on the roof of the lower wing of the building, and the second key element is on the roof of the technical centre. In addition, a large number of photovoltaic modules are integrated into the building’s façade and act as a shading system in addition to generating electricity. Finally, plants serve to provide greenery.
With a view to the future, measures have already been taken to meet the demands of e-mobility. In addition to parking spaces, the underground car park also offers charging stations for cars, e-mopeds, and e-bikes.