Envafors: Managing sector-coupled heating networks with Gradyent’s Digital Twin  

Envafors, a Danish multi-utility company formed through a collaboration between several municipal utility companies, has been at the forefront of sustainable energy solutions.  

Operating a 240-GWh district heating network in Slagelse and a 70-GWh district heating network in Korsør, primarily on biomass and electricity, Envafors has shown a commitment to providing clean, reliable heat to its growing customer base. 

The company is implementing Digital Twin solutions for both sites. The Slagelse and Korsør Digital Twins are already running live, producing estimations for the entire networks and optimizing temperatures.

Challenge 

Envafors is rapidly transforming, adding new connections and installing 10 MW heat pumps in both networks. These advancements bring new challenges due to growing system complexity.  

The company operates a complex production setup, where new heat pumps in Slagelse can directly acquire electricity from biomass-fired CHPs. However, volatile electricity markets may make market acquisition more cost-effective. In Korsør, the operators must optimally manage the buffer to deal with uncertainty in forecasted production from the solar heat production site. Additionally, large heat accumulators in Slagelse and Korsør add complexity to optimal charging and discharging times.  

To maintain reliable and clean heat delivery, Envafors needs a system-level view, achievable through a Digital Twin solution. Recognizing this need, Envafors partnered with Gradyent, whose Digital Twin solution is trained on Envafors' data for an accurate representation of the heating system. 

Solution 

Gradyent's solution tailored to the company’s unique needs creates a digital replica of the physical heating system.  

Envafors and Gradyent have first deployed the Digital Twin in the network in Korsør, then in Slagelse. It will be positioned in the central control room where operators manage both networks. Operators receive optimal control recommendations through a secure connection to SCADA systems, fostering trust in the Digital Twin. This advancement aligns with Envafors' vision to ultimately automate its district heating systems. 

Results

The Slagelse Digital Twin is running live and produces estimations for the entire network, including the estimation of the 'Transmission' pipeline and meshed Distribution network. 

The Envafors-Korsor is running live as well, delivering estimations and temperature optimization, leading to a potential reduction of forward temperatures by 9°C compared to a competing solution. The solution is estimated to potentially reduce heat production by 1.1%. 

Gradyent ensures the Digital Twin remains continuously updated and synchronized with real-life operations to provide optimal setpoints. This is crucial for Envafors, which aims to add 2.000 connections annually until 2030.  

Unlike previous software, Gradyent's Digital Twin operates on a modern Software-as-a-Service (SaaS) model, simplifying maintenance and operation. Placing the Digital Twin at the core of operations maximizes efficiency amid ongoing system growth and transformation for Envafors. 

Next steps 

Gradyent and Envafors are actively testing a Digital Twin for optimizing source dispatch, aiming to enhance real-time efficiency in multi-source heat management. By integrating E-boilers, heat pumps, solar energy, and biomass into a coordinated system, the goal is to refine buffer operations and dynamically adjust setpoints based on real-time data. This approach promises improved energy utilization and responsiveness, ensuring that heat generation is both sustainable and adaptive to fluctuating demand.  

The Digital Twin framework offers predictive insights and strategic control, paving the way for smarter and more resilient energy networks. 

“The Danish heating market is rapidly changing and adapting to a new reality with electrification and decentral heat sources. This calls for real-time optimization with an end-to-end approach. We’re very happy to enter into this long-term partnership with Envafors, again showing how vital digitalization is when complexity is rising.” 

Steen Schelle Jensen, Business Development Director at Gradyent