Tallinna Küte district heating system

Tallinna Kute DH System 
 Photo: COWI/Søren K. Christensen.
During the past years, the Estonian district heating company, A/S Dalkia Eesti Tallinna Küte, has worked intensively with optimising and integrating operations and services.

The company supplies more than 200,000 of Tallinn’s inhabitants with heat and has a production capacity of approximately 1600 MW.

One of the main initiatives concerned the change from fixed flow to variable flow operation. As part of this process, Tallinna Küte discovered the need for an overall system solution linking the digital network data (GIS), the SCADA system, the invoicing systems and the hydraulic tools.

TERMIS "real time"

The district energy management system, TERMIS, offered the most appropriate software solution, and COWI was engaged to assist and facilitate the development of a company system in close cooperation with the staff of Tallinna Küte. Hence, extensive training became the most important aspect throughout the project.

Development of a solution

The project started up with an off-line modelling of the hydraulic system, calibrated on the basis of actual measurements of the district heating system, and then converted into real-time mode by the direct coupling of the SCADA system.

Finally, the system was implemented as an internet-based ASP solution, allowing Tallinna Küte to operate multiple networks from one central control centre, with only a few – if any – staff on site.


Tallinna Küte has now easy access to detailed information on consumption patterns and the actual operational situation. Thus, TERMIS is automatically calculating and saving information on the current state of flow, pressure and temperature throughout the network at a configurable cycle time.

Additionally, every real-time model calculation cycle includes an updated forecast simulation for a given period. This allows the company to be abreast of demands, enabling optimisation of operations and planning of the future.

High level of utility

Some of the notable results are:

  • Prognoses calculated by the TERMIS model differ from the actual consumption by less than 1%;
  • Heat loss calculations for specific areas can be calculated with very high levels of exactness;
  • Real-time calculations have turned out to be extremely valuable when determining solutions to be applied in case of maintenance and/or repairs.

COWI has continued the cooperation with Tallinna Küte through a hot-line service agreement.

LAST UPDATED: 19.09.2017