Energy in public housing

A 40 kWh GREENROCK saltwater battery storage optimizes self-consumption of a residential estate of NHT in Wörgl.

The first building was ready to move in 2019. The whole district will transfer into a smart City during the next years. The learning from the first construction stage are upgraded in the following stages.

The storage system is part of a Smart Cities funding program, the Klima- und Energiefonds in Austria.

Watch in the German video how a smart City evolves.

Film Smart City

Watch the video

Project description

The housing district “Südtiroler Siedlung” in  Wörgl is being rebuilt. In five stages there are built new state of the art residential building on 27,000 m². For the first construction phase, the above-mentioned funding project was implemented. This involves the coordination of various innovative measures in public housing in order to reach better self-consumption.

This includes:

  • connection to the district heating supply, which is fed by industrial waste heat
  • installation of a PV system on the roof of the building (29.76 kWp)
  • Supplemented by a 40 kWh GREENROCK saltwater battery storage
  • Commissioning a circulation heat pump to recover the heat losses in the plant room
  • Networking via smart ICT (information and communication technologies) to measure and control the systems and provide simple information for tenants
  • Charging and mobility management

The Saltwater battery

In the bicycle garage of the new building there is room for the salt water battery storage. NHT adapted the construction plans and created a small room with approx. 4m². This is enough space for the 40 kWh GREENROCK Business Storage. The bicycle garage is at ground level and could be easily reached with lift trucks and hand trucks for the set-up of the storage.

Completion and final assessment by the property developer NHT – Mr. DI Harald Konrad Malzer for the business area energy efficiency and sustainability

Tür zum Speicherraum

Bei der Begutachtung des Speichers

Anschluss Batterien picture source (all 3) NHT

The new tenants moved into their apartments in November 2019. They now live in an apartment building that sets standards above those usually found in public residential buildings. In addition to the structural and energy-related features, the tenants can grow their own vegetables. NHT offers the possibility of urban gardening on the roof terrace of the building. On the remaining roof areas there is a PV system of 29.76 kWp in total.

Wörgl NHT Projekt von oben

Image of the completed first construction phase with view of the installed 29.76 kWp PV system; source: NHT/Robert Schober

partners in the project

What’s behind Smart City Wörgl?

The German Video explains:

Filmstreifen WIB

Guilty as charged: The project team stands for a smart City with its green and ecologic effects.

Watch the German Video: Was steckt hinter Smart City Wörgl

Future projects in planning

Rum residential complex: the evolution of building

The climate turnaround also extends to non-profit housing. In Rum near Innsbruck, the world’s largest Passive House PLUS residential quarter will soon be built. What does that mean? A passive house refers to a building that is truly energy-efficient, comfortable, economical and environmentally friendly at the same time. The heat loss typical for buildings is drastically reduced. This is achieved through high-quality thermal insulation, windows with triple glazing and an airtight building envelope in combination with comfort ventilation.

Added value for residents

The energy for the general building services, including heating and hot water, is largely self-produced. The photovoltaic modules (710 square meters) located on the roof capture the energy given by the sun. Part of it can be used directly. In planning is that the electricity not immediately needed is stored temporarily – with a salt water energy storage.