Energy-efficient transport system from Billund to Grindsted

Sweco has designed a solution to provide Billund Vand with a flexible, future-proof, energy-optimised and centralised wastewater system for years to come.


Customer: Billund Vand

Period: 2013–2015

Location: Billund and Grindsted


With a wish to utilise the resources inherent in wastewater, the utility of Billund Vand issued a call for tenders for a turnkey contract involving the closing down of the Billund Wastewater Treatment Plant and the transportation of the wastewater for treatment at the Billund BioRefinery in Grindsted. 

As turnkey contractor, TC Anlæg joined forces with Sweco, Grundfos and Intego to design and carry out the overall centralisation project based on the framework specified in the tender documents. A reliable, fully functional system had to be ready for commissioning by November 2015.

Flexible, future-proof and energy-efficient solutions were the principal elements throughout the project. Sweco was responsible for the overall design of the centralisation system, the technical dimensioning, process calculations, optimisation and project planning of all parts of the transport system, as well as the regulatory processing and the conducting of an Environmental Impact Assessment (EIA). Billund Vand has reduced its energy costs substantially, which ultimately benefits both the environment and the consumer.

A project of this dimension and complexity has made big demands on the collaboration between project team and client in order for the team to be able to deliver a faultless system that worked from the very beginning.

Technical data: 

  • An elevated reservoir to establish the needed pressure for moving the wastewater from Billund to Grindsted, 7 metres tall (4.3 metres of which are currently in use). The remaining capacity is intended for future proofing.
  • 2 transportation pipes, 17 km long and 400 mm in diameter.
  • 2 rainwater pumps, provided by Grundfos, which transport 300 litres/second up into the 4,300 m3 rainwater basin.
  • Up to 150 litres of waste water are transported per second from Billund to Grindsted.
  • The existing lagoon system, with a total of 6 lagoons, will be reused for final polishing of the overflow water.

Customer quote

"Due to the substantially greater-than-expected reductions in electricity consumption, we have received a reliable, profitable system that pays for itself sooner than anticipated. This is based on the fact that, during the first month of system operation, we used only 240 kW to pump 5,000 cubic metres of wastewater from Billund to Grindsted. This indicates that we can cut substantial costs which will eventually benefit the environment and the consumer. Compared to the previous level of electricity used by the treatment plant, the above-mentioned 240 kW equated to a 60% reduction in the first month after the transport system was commissioned, which is very satisfying! Since the commissioning of the system, it has turned out that the concentrated wastewater from Billund improved the degree of purification at the Billund BioRefinery in Grindsted as it fuels a better conversion of the organic material found in the wastewater."


  • Per
    Department manager, Water & Energy North
    +45 8210 5138
    Fraq rznvy