The property right at the entrance to the municipality is less than 10 kilometers away from the city of Winterthur and is still an idyllic piece of land, with a direct connection to the banks of the Töss and with a view of meadows and forest. The goals of the Energy Strategy 2050 are being built here. The Verde Blu development has been inhabited since autumn 2019. So far, so normal. It is noteworthy, however, that this development covers a large proportion of its energy requirements itself and that exclusively from renewable sources. “The specifications of the Energy Strategy 2050 are an opportunity for the real estate industry,” explains Dieter Stutz from Atlantis AG, which is active in the areas of environmental consulting, settlement planning and architecture and who developed the project. The heat supply via groundwater was the best and most convincing solution for the area. Atlantis planned and implemented this complex construction project together with EKZ.
Sustainable living as a need
The new construction project Verde Blu with nine residential and commercial buildings comprises 108 condominiums as well as various commercial areas that are used by a Migros branch, a community and a physiotherapy practice, among other things. An old, listed barn serves as a common room and provides rustic charm on the site. In contrast to this is the state-of-the-art technology that supplies the system with energy: groundwater is used as a heat source for the heating and hot water, which supplies the houses with decentralized heat pumps via a so-called anergiering. An anergiering is a cold local heating system that, in contrast to conventional local heating systems, works with transfer temperatures below 30 degrees Celsius. Anergy networks therefore have no heat losses in the lines, but even generate additional energy gains from the ambient heat. In summer, the buildings can be passively cooled with the groundwater via the anergy ring.
A photovoltaic system, which is optimally designed to meet the needs of the building, provides the electrical energy for the building. The complex was only built after the apartments had already been occupied. Because they wanted to leave the decision for or against solar power to the owners. The fact that the system with a peak output of 100 kilowatts was approved by an overwhelming majority at the first owners’ meeting in winter 2019 speaks for itself. Martin Nicklas, who is responsible for modern energy solutions at EKZ, is not surprised: “In the real estate sector, we have long known the need to make a contribution to sustainability in the living area too.” A charging infrastructure for the 209 parking spaces was installed in the lower-level garage. Thanks to load curve management, it is possible to charge the cars in stages if a whole fleet of electric vehicles should one day populate the garage.
Well-coordinated system
In Kollbrunn, power generation as well as heating and cooling generation and electromobility are combined in an integrated energy system. The centerpiece is an intelligent control system that maximizes the self-consumption rate and takes over load management. In this way, what is actually the most important goal can be achieved: that the electricity produced by the PV system is also consumed as much as possible on site. The control uses weather forecasts from an external weather portal for this purpose. An algorithm in the control system evaluates this data and decides on the previous evening whether enough solar power will be produced the next day to charge the boiler and storage tank of the heating system. If the solar production is too low, the boilers are charged during the night at the low tariff, otherwise there is a wait until there is enough solar power available the next day to start the heat pump.
On-site energy production
The “Grand Chemin” development was built in Epalinges in western Switzerland, with some of the electricity required being produced on site by a photovoltaic system (PV). A new multi-family house is being built in Emmen (LU), which will be characterized by a heat pump with groundwater and a PV with ZEV. Two examples out of many that show that the future of energy has long since begun.
