We have been working with Jani Uitti, Senior Network Asset Manager at Turku Energia to provide more insights into their network and further decarbonise their heating system. We have taken the opportunity to ask Jani about his vision of the challenges and opportunities in district heating. ‘Understanding heat propagation by making a digital copy of the network can help with peak shaving and reduce the usage of our oil boilers’.

Finland is a ‘top 3’ country in Europe in terms of district heating adoption (50%) and percentage of renewable energy used (58%), according to the recent market report by Euroheat & Power. Turku Energia is a district heating company in the southwest of Finland, supplying energy to about 5,000 customers and around 190,000 end users, for about 2,000 GWh heat per year, through 650 km of network with tunnel and surface networks combined.

Turku partnered with Gradyent to further decrease its reliance on fossil fuels. By developing a Digital Twin of the heating system, Turku aimed to gather insights into the heat propagation through the network to lower the cost of production and decrease the reliance on oil boilers. We spoke to Jani, who has an exciting challenge on his hands: leading Turku’s network on their journey towards carbon neutrality.

Turku is aiming to become carbon neutral by 2029 when the city is celebrating its 800th anniversary. What is Turku’s main obstacle in reaching this goal?

‘The main challenge for Turku’s district heating network to become fully carbon neutral is the high peak demand that is experienced during the morning hours. To supply the system during peak demand, the oil boilers are turned on to provide a quick supply of hot water to the network. Understanding the mechanisms of heat propagation in the network can help with peak shaving and better controlling the heating supply to rely less on the oil boilers, which have a higher carbon footprint.’

The Turku network is doing very well with 93% efficiency and sources that are 80% renewable. What were the main actions that helped Turku get there?

‘Turku Energia has managed to raise the share of renewable production by showing courage, that’s the most important thing. There were moments when some investments did not seem so smart as they were not profitable, but they were good for the environment. For example, investing in a multi-fuel power plant which was commissioned in 2017 was seen as something risky at the time. We took the risk, and it has made a huge impact contributing to decreasing the network’s carbon footprint. Also using shunting technology from the 90s has also helped the network become more efficient by varying supply temperatures through varying flow.’

What software systems have you been using and what was missing for you?

‘There are a lot of different technical systems that we use to visualise and control our network. For example, a GIS system is used to visualise the network, having an accurate network file with pipe diameters, lengths and pathways is an important step towards doing any sort of dynamic modelling. A big bottleneck is getting the systems to talk with each other showing temperatures, flows and pressures in the relevant areas. Most of the operational decisions are based on an interpretation of these multi-system outputs, assessed by operators and then an operational decision is made.’

Why did you choose to work with Gradyent?

‘I wanted to reduce the usage of our oil boilers through dynamic modelling. Having a technical and modelling background of 10 years myself, I knew what parties were out there. I enjoyed the technical depth presented in the demos given by Gradyent. The approachability of the team and the technical language your team speaks gave me the comfort I needed.’

‘Ideally, we can prevent the firing up of one oil boiler during the morning peak by following a peak shaving strategy, using the heat propagation dynamics of the system. Even saving 1 GWh of oil would significantly benefit the Turku network.’

What did you think of the cooperation?

‘I have been very impressed with the data validation workshop where the Gradyent team came to the control rooms of Turku Energia and gave a presentation on the data that they had received from the users and sources of the network. The team presented the network in a new way, together with strong visuals on the heat movements between users.’

’Working with Gradyent and the Digital Twin provided valuable insights into how digitalisation can assist energy companies in visualising their network operations. It also shed light on how modern tools can be utilised to tackle optimisation challenges effectively.’

All Finnish district heating companies are working hard towards carbon neutrality. What is one thing that everybody should be doing?

‘All new buildings built after March 2022 will be required to operate at a maximum temperature of 90 °C instead of the current 120 °C. This means that networks should be able to handle the heat transfer capacity throughout the network with higher flow rates. Lower temperature requirements for customers means higher flow rates in the pipeline and hence larger pressure losses. Finnish district heating companies should be looking into digitalisation to optimise their networks within these new requirements. Dynamic modelling can be very supportive to make heating available and affordable to all customers.’