The 18 km-long Fehmarnbelt tunnel with its electrified rail operation and a fully lit road tunnel requires the security of an uninterrupted power supply. It will have its own, major substation at Rodbyhavn. The substation will occupy 20,000 sq m and will supply power equivalent to a total annual electricity consumption of 60 gigawatt-hours (GWh) to the Fehmarnbelt tunnel. This corresponds roughly to the consumption of a large provincial town with 10,000 households. The total power is approximately 120 MW.
Proven technology and construction methods include climate-proofing, so that the substation is not in danger of being flooded by storm surge on the low-lying island of Lolland. This will be achieved with a cofferdam driven into the ground, which will form a watertight, 4 m-high barrier around the substation.
Furthermore, there is the need to ensure that the huge, high-voltage facility does not interfere with the surroundings in sparsely populated areas. For example, by affecting the train on the way to and from the tunnel. If it is not shielded effectively against electronic noise in the form of electromagnetic radiation, it may, at worst, mean that the power is turned off, or mobile phones crash. The problem will be addressed by applying new technology, which integrates converters and strikes a balance between the various phases, so that there is no noise interference in the power network.
The electric trains will use most of the power from the substation, but it also has to provide power for all the technical equipment in the tunnel, such as lighting, pumps and ventilation.
The plan is that the trains will run on Danish power through the tunnel and along a short stretch of land on Fehmarn, where they will switch over to the German electricity system. The Germans will be able to engage a temporary supply if the power were to go down in the tunnel.
Femern A/S has pre-qualified three consortia to bid to build the substation and expects to receive the final offer for the substation at the end of 2015 with the contracts being signed in 2016. Click dk/14 for tunnelbuilder archive. Visit http://www.femern.com. 38/14.
