For two years, Wien Energie has been optimising various heating networks by working with Gradyent’s Digital Twin Platform. In April 2023, Wien Energie and Gradyent are starting the heat pump optimisation project to lower the temperature of the thermal network in Oberlaa. This will increase the efficiency of the recently installed heat pump, creating around 10% more heat with the same amount of energy.

Building a Digital Twin of the Wien Energie district heating system

In 2021, Gradyent participated in the Wien Energie Innovation Challenge. For this competition, within 6 weeks we developed a Digital Twin for one of the nearly 600 secondary networks of Wien Energie to showcase the value of temperature optimisation for the network and won the competition.

With the real-time Digital Twin Platform, Gradyent created a digital copy of the complete grid that runs in real-time, combining geographical, weather, and sensor data with physics-based models and AI. Digital Twin provided insights for the entire network – even for places where no data or smart meters were available. After this successful pilot, Wien Energie and Gradyent expanded their collaboration and developed Digital Twins of other secondary networks to scale up the savings and impact.

Michael Strebl, CEO Wien Energie: “With the Digital Twin, we ensure our district heating network is fit for the future! By optimising the temperature, we can reduce the forward temperature in the selected district heating secondary networks by an average of 4 degrees. This enables us to deliver valuable heating energy to our customers even more efficiently.”

Lowering the temperature and heat loss and saving operational costs

For two years, Wien Energie has been lowering the network temperature for multiple networks by using the Gradyent Digital Twin, and by doing this, has decreased heat loss and CO2 emissions and saved operating costs. For instance, as the result of digital twin integration, the temperatures were dynamically reduced on average by 4°C. Wien Energie sees a lot of potential in this approach: if rolled out to the 20 largest secondary networks, the company could save up to 4,000 MWh of heat.

Besides the direct savings, the security of supply could be increased, and valuable insights could be delivered on the network showing a detailed potential on return temperature, hydraulics, and pump efficiencies. By building the Digital Twin, we gathered valuable insights about the behavior of the network. Anomalies, alerts, and maintenance as well as potential savings in networks including heat pumps have been outlined leading to a deeper understanding of the Digital Twin value at Wien Energie.

Expanding to heat pump optimisation to increase efficiency and added value

From February 2023, we are expanding our cooperation to further optimise the Wien Energie heating system by optimising the heat pump operation at the bathing spa “Therme Wien”. By lowering the forward temperature in the district heating network, the efficiency of the heat pumps in that network will be increased. By lowering the forward temperature, we expect to save up to 10% electricity consumption of the heat pump. That means that around 10% more heat can be produced with the same amount of electricity.

Sebastian Schirber, Solutions Director Gradyent: ''We are very proud to work in partnership with Wien Energie to transform the Vienna district heating grid, achieving a more sustainable and operationally efficient way of producing energy. The Digital Twin of the district heating system makes it possible to decrease temperatures in the network and enables the integration of renewable sources while achieving higher efficiencies for heat pumps.”