SEI, the district heating operator in Mantova, is on a strong decarbonisation journey. In the past years, SEI has been pursuing the improvement of the sustainability of the district heating grid of the City of Mantova, with the goal of significantly reducing its CO2 emissions. SEI recognises digitalisation as a key enabler and has chosen Gradyent as its partner to optimise the district heating system with a Digital Twin.

Challenge

SEI has a strong ambition to decarbonise its system and reduce total gas usage. To realise this, SEI is investing in renewable energy sources and improving the energy efficiency of the total system. On the latter, SEI sees data collection and analysis as a key enabler in achieving its targets. In doing so, SEI is increasing its visibility on the required investments and maximising potential opportunities for smarter and greener operations.

Solution

Building and implementing a real-time Digital Twin

In 2020, SEI started the collaboration with Gradyent by developing a ‘Digital Twin’ of the district heating grid. The Gradyent Digital Twin Platform creates a digital copy of the complete grid that runs in real-time, combining geographical, weather, and sensor data with physics-based models and AI. It provides insights into what happens in every part of the system, allowing district heating companies to optimise their grid during operations to realise higher efficiencies as well as run simulations of large changes to the system.

Gradyent built a Digital Twin of the entire Mantova system and trained it with historical data that SEI had available. The data included time-series data from the production assets (the central CHP, peak boilers, and the accumulator), the network, the substations, and GIS-data. By combining all the data with a thermohydraulic model, an accurate virtual representation of the full system could be made that matches the real-life situation. SEI was now able to evaluate accurately the benefits of working with lower temperatures in the network and saw that the potential for optimisation was significant.

The process was led by the Gradyent team through analysing the data, presenting main insights in several data validation workshops, and building the Digital Twin, while the SEI team shared its knowledge of its district heating grid and gave feedback on the findings during the workshops.

Results

Significantly reducing heat losses and CO2 emissions

The Digital Twin calculated that the benefits of reducing heat losses with temperature reduction over a full year significantly outweighed the additional pumping costs. Also, the Digital Twin stayed within all system constraints during its minute-to-minute analysis. This created a trust for the operators of SEI, showing that the Digital Twin was the right way of translating potential into value for its operators.

During the 2022-2023 thermal season, SEI successfully tested the adoption of the operating settings suggested by the Digital Twin, which made it possible to improve the efficiency of the Mantova district heating grid during actual operation and achieve a reduction of more than 550 tons of CO2 emissions per year compared to the previous operation.

Next steps: optimising the accumulator and integration with the control room

Gradyent and SEI have jointly developed a multi-year roadmap to extend the partnership to further digitise and optimise the Mantova system. In the coming months, the Digital Twin will be refined, aimed at optimising the management of the heat accumulator, and at integrating and live connecting the model in the new control room of SEI.