DIN Forsyning and Drone Systems: The hunt for leaks in the district heating network continues – Drones have revealed new fractures

Date: 14/04/2021

A drone thermography over Østerbyen and Kvaglund has revealed ten new breaks in the district heating network at Din Forsyning, which since November has been plagued by an unusually large water loss of up to 500 cubic meters of hot water per day.

The large-scale hunt for fractures and leaks in Esbjerg's district heating network is now continuing for the fifth month, but there is light ahead, says Thomas Bornhøft, recycling and distribution manager at Din Forsyning.

Since November, he has been in charge of a search team that has been tasked with finding the reason why the district heating network suddenly lost up to 500 cubic meters of water a day, corresponding to about 200 cubic meters more than usual, which was bad news for both the CO2 accounts and the Esbjerg residents' heating bill.

Now, however, it is finally starting to lighten up. With the help of thermographers, drone flights (from Drone Systems), we have managed to locate over 40 fractures. With loss now reaching about 350 cubic meters of hot water per day. This means that we are approaching acceptable consumption, says Thomas Bornhøft.

Help from drones by Drones System
From the air, the drone can use a thermal sensor to measure heat radiation and identify abnormally high temperatures and the probability of a leak, and this has proven to be extremely effective.

- The biggest advantage of using drone flying rather than thermography from a car is that we can check the branch lines all the way to the houses as well as the internal lines. The results of both the drone flight and our thermography from car have confirmed there is a challenge with lack of maintenance of the "private" district heating lines. The housing associations and owners' associations are good at having their wires repaired when we inform them that they have a break, but it lags a bit with preventive maintenance and replacement, says Thomas Bornhøft from Din Forsyning.

The drone flights over eastern Esbjerg are just the first stage of a larger, planned drone thermography of the whole of Esbjerg and Varde. Flights will take place over the next five years, and the hope is that in this way even more leaks can be found in the district heating network.