State-of-the-art technical equipment at a historical location

Refurbishing the drinking water supply system

The central drinking water supply system in the University and Hanseatic city of Greifswald dates back to 1888. The Groß Schönwalde waterworks was built as an extension in 1914. The associated drinking water reservoir was located at an elevated point 2.5 km away. In 1983, another drinking water reservoir (5,500 m³) was put into operation next to the old reservoir (1,000 m³). However, after determining that these reservoirs no longer met current engineering codes and standards for water storage facilities, the municipal utilities provider decided to replace them with a central drinking water supply system located on the Groß Schönwalde waterworks site.

Stadtwerke Greifswald GmbH

Stadtwerke Greifswald GmbH supplies more than 70,000 people in households and commercial businesses with electricity, gas, drinking water and district heating in Mecklenburg-Vorpommern, especially in the district of Vorpommern-Greifswald. They deliver around three million cubic metres of drinking water a year to the consumers via a network of pipelines measuring almost 320 kilometres.

Energy efficiency takes top priority

When selecting the pumps, the focus was on energy efficiency. Despite a historic city centre and surroundings popular with tourists, the region around Greifswald is weak in terms of infrastructure. The large number of students relative to the overall population may make Greifswald Germany’s youngest city; but it is precisely these demographics that compel a responsible energy supplier to ensure that energy costs remain consistently affordable in the long term. And this requires the use of outstanding technology.

Consistently optimised emergency water pumps

Between 2005 and 2018, the old building of the Groß Schönwalde waterworks was completely renovated in stages and a new building was constructed. All technical equipment was also renewed. The new building featuring four chambers with respective capacities of 900 m³ (3,600 m³ in total) and an integrated pressure boosting station blends in well with the historical ensemble. The Groß Schönwalde facility delivers approx. 60 % of the daily volume of drinking water needed to supply around 60,000 inhabitants of the city of Greifswald. The total daily demand is between 7,000 and 11,000 m³ of water.

With energy efficiency in mind, Stadtwerke Greifswald opted for pumps from KSB and made the following selection:

• For water transport: 3 Etabloc 150-125-200 GB AV11D301104 B with PumpDrive 2.
  For pressure boosting: 4 Multitec A 125/2-10.2 12.167 with PumpDrive 2 and a Multitec A 65/3A-6.1 12.167 with PumpDrive 2 which serves as a pump for night-time operation.

The Eta pump is a classic that has proved successful over decades and has been a constant focus of optimisation for KSB. It also represents the globe’s most popular family of standardised water pumps – 1.5 million of them are in use worldwide. The Eta pump impresses with its energy efficiency and ease of service. Its excellent efficiencies already meet the energy requirements of tomorrow. Maximum energy savings are achieved via variable speed operation with PumpDrive 2 which continuously adjusts the pump’s output to the actual demand.

Multitec is one of the most versatile pumps in KSB’s extensive range of products. A wide range of available materials and designs ensures an ideal match for the fluid to be handled and the system the pump will be installed in. Flexibility, reliability and ease of service ensure a long service life and low operating costs.

All of the new facility’s components were installed by MBA Anlagenbau GmbH from Neubrandenburg. Commissioning was conducted by KSB’s service partner Stancke Elektromotoren und Pumpentechnik from Grimmen.

In the month following commissioning of the completely revamped Groß Schönwalde waterworks, the results proved impressive. Not only did the pumps’ performance range exceed all expectations, the energy savings were and continue to be very satisfactory.

In figures: The specific energy consumption of the entire facility dropped from 0.40 kWh/m³ to 0.34 kWh/m³. This results in energy savings of 15 %. An average annual consumption of 650,000 kWh achieves savings of 97,500 kWh/a.

In the coming years, Stadtwerke Greifswald will continue to improve the energy efficiency of its drinking water pumping and pressure boosting systems as part of its energy management strategy. KSB will provide support as a reliable partner.

Figures I Data I Facts

Object:
Waterworks

End user:
Stadtwerke Greifswald GmbH

Project data:

• 3x Etabloc 150-125-200 GB AV11D301104 B with PumpDrive 2 (intermediate pump – water transport)
• 4x Multitec A 125/2-10.2 12.167 with PumpDrive 2 (main-load pumps – pressure boosting)
• 1x Multitec A 65/3A-6.1 12.167 with PumpDrive 2 (low-load pump – pressure boosting pump for night-time operation)