Winner water 2019


Winner GTI Awards 2019 – Water

Holistic energetic optimization of the drinking water supply for the offshore, Helgoland

General information:

Island (Region, Province, Country):
Helgoland, Germany


Budget / cost of the project:
€ 1.200.000

Project objectives:

Within a holistic energetic approach, the Project Objective is to optimize the drinking water supply for the Island Helgoland. The use of drinking water tanks and cisterns and the construction of a CHP, which i.a. the supply of the aggregates of the drinking water system was transformed. 345 out of 766 tonnes of CO2 (45%) now can be saved per year directly in the drinking water system. Including the CHP, the saving increases to 658 tonnes of CO2 per Year.


Project description of activities and specific interventions:

The drinking water supply comes over 80% from seawater. More than 130,000 m³ of drinking water is produced each year. The seawater desalination plant works on the principle of reverse osmosis. Multi-stage electric centrifugal pumps with drive motors of 160 kW each. The Utilities Helgoland (VBH) carried out in 2018 and 2019 a holistic energetic optimization of the drinking water supply under the challenging conditions of the island. In the spring of 2018, the plant was subjected to a hydraulic and energetic overall analysis. Two of the decisive approaches to energy consumption were the replacement of the multistage high-pressure centrifugal pumps for drinking water desalination and the network pumps with significantly more efficient pump types. The high-pressure pumps are currently being replaced by highly efficient, variable-speed axial piston pumps manufactured by Danfoss [scheduled for completion by March 2019]. At the same time, ISAVE pressure exchangers, also by Danfoss, are being installed in a network that recovers a considerable proportion of the energy (pressure!) Of the discarded water. With these measures, energy consumption can be almost halved to 455 MWh. Every year, 204 t of CO2 emissions are avoided.


Public outreach, education and awareness efforts and results:

Helgoland set an ambitious target in 2013 to become a Zero Emission Island by 2020. So far over twelve sustainability projects where accomplished successfully with a high visibility on the Island and in Germany. As also being a partner and member of the GTI Laboratory Helgoland and Facilitator of the 1st Conference of German Islands in 2019 the Media and thousands of the visitors are following Helgoland, being at the forefront in testing, adopting and implementing sustainable island solutions. The water plant on Helgoland in the global context of the Drinking water supply challenge plays an important and tangible role due to its very uniqueness.


Economic value added and how calculated:

Project period: July 2018 – June 2019
Cost: 1.200.000 €
Annual Saving: 115.000 €
Previous annual consumption: 1.402.439 kWh
Absolute annual Energy savings: 575.000 kWh
Relative annual Energy savings: 41,0 %
Relevant Energy source: Electricity


Ecological and social project outcomes:

Savings in CO2 Emissions by 45%.
Maintaining a high Drinking water quality.
Keeping the price stable.
Enhancing the sustainability goals of the Municipality and tourism.