The building design, the concepts for climate and energy and the building materials aim for the lowest possible CO2 footprint. The use of local energy is a determining criterion of the energy concept. Local and renewable sources are used intensively: The sun is used to generate electricity via façade and roof-integrated photovoltaics, combined with geothermal energy via activated piles and local heating / local cooling. The base load of heating is covered by a heat pump via the activated piles; the peak load is covered by local heating. This approach maximizes the use of renewable sources while reducing technical space in the building.
PV modules are provided on the roof and façade, depending on mounting options. The energy generated is used to operate the building's technical systems and to cover the general consumption of the offices. If excess energy is generated, it can be optionally fed into the grid or directed into a battery buffer storage to supply the building grid when the PV system is not productive.
Radiant cooling and heating is provided for the office areas. Concrete core activation is used for this, which works with small temperature differences and is very suitable for free cooling, meaning it works with groundwater temperatures. The individually developed facade provides passive shading in summer thanks to the "zig-zag" arrangement, but also allows the photovoltaic elements to provide solar input in winter. In addition, the facade gets a decentralized ventilation unit with heat recovery in every other axis, which supply the areas located on the facade.
The CO2 balance of the building is considered over its entire life cycle, including all energy used during operation. The property forms the balance boundary, which is recorded as "imports" and exports" over the year. In this balance the CO2 emission in operation and the grey energy of new building construction with its large mass must be compensated; therefore, the plot alone is probably not sufficient. To achieve the necessary surplus production per year, other strategies must be added, such as an own wind turbine.