Schwalbach, April 14, 2026: Mayor Alexander Immisch today welcomed representatives from Süwag and maincubes at Schwalbach City Hall for the signing of two agreements shaping the future of the city’s heat supply. Together with Dirk Gerber, Managing Director of Süwag Grüne Energien und Wasser GmbH & Co. KG, Mayor Immisch signed a cooperation agreement governing the continued operation of the Schwalbach district heating plant. The agreement outlines the long-term operation of the facility, the comprehensive modernization of all core technical systems, and the expansion of the network to serve additional areas.
It further establishes a clear commitment to the full decarbonization of the heat supply – namely, the complete phase-out of fossil fuels – by 2045. To this end, Süwag will invest up to €22 million by 2030.
“With this agreement, we have successfully concluded the intensive negotiations of recent months,” said Immisch. “In Süwag and maincubes, we have strong and dependable partners by our side who will ensure that all residents and businesses in Schwalbach benefit from long-term access to a secure, customer-focused, and climate-neutral heat supply.”
Gerber added: “We are proud to continue playing a responsible role in Schwalbach and to help make its heating infrastructure fit for the future.”
At the same time, Dirk Gerber and Oliver Menzel (Founder and CEO of maincubes) signed a waste heat utilization agreement. maincubes is currently developing its FRA03 data center at Kronberger Hang, whose waste heat will, in the future, be integrated into the city’s heating infrastructure. To enable this, Süwag will construct a dedicated heat pump facility on the maincubes site. There, the waste heat generated by the data center will be upgraded to a suitable temperature level using large-scale heat pumps. The recovered heat will then be fed into Süwag’s district heating network and delivered to customers, where it will reliably provide space heating and domestic hot water.
“Data centers today are far more than mere data processing facilities – they can serve as active enablers of sustainable urban development. The Schwalbach project demonstrates how strong partnerships can meaningfully align technological innovation with the municipal heat transition,” said Oliver Menzel, Founder and CEO of maincubes.
That said, some time will pass before waste heat from the data center can fully contribute to Schwalbach’s heat supply. Süwag plans to begin construction of the district heating network extension toward the data center in October of this year. Over the course of the following year, additional infrastructure will be implemented, including the energy center at the data center site, large-scale heat pumps, thermal storage systems, new pipeline infrastructure, and comprehensive efficiency enhancements. Commissioning of the modernized district heating network is scheduled for 2028.
Media contact:
City of Schwalbach
Achim Lürtzener
Tel. 06196-804-194
E-Mail: achim.luertzener@schwalbach.de
Süwag Grüne Energien und Wasser
Katja Heise
Tel. 069 3107-1689
E-Mail: katja.heise@suewag.de
maincubes
Catherine Chehimi
Tel. 0151 5502 5699
E-Mail: Catherine.Chehimi@maincubes.com
Schwalbach am Taunus is a small city in a major region – located in the heart of Germany and at the center of Europe. Like a “prime cut,” the city stretches from Frankfurt’s skyline to the Taunus Nature Park. It benefits from a calm, scenic setting combined with excellent transport connections. Distances are short in every direction: to the metropolitan area, to nature, within the city itself, and not least to City Hall. In addition, Schwalbach is an attractive location for education, offering a strong school landscape. A wide range of successful companies have already recognized and embraced the advantages Schwalbach has to offer. For more information, please visit: www.schwalbach.de
Süwag Grüne Energien und Wasser AG & Co. KG (SGEW) is a wholly owned subsidiary of Süwag Energie AG. It consolidates the company’s activities in the fields of renewable energy and heat supply. Guided by its vision and commitment to “Making energy better” (“Energie.Besser.Machen.”), SGEW is actively driving the energy transition forward. As a dedicated partner to municipalities, the company plays a key role in advancing the heat transition: it supports cities, municipalities, and businesses in planning and implementing innovative heating solutions.
SGEW is progressively modernizing and decarbonizing its portfolio of approximately 340 existing heating facilities while working closely with its municipal partners to develop sustainable energy concepts. By 2030, SGEW aims to secure access to one terawatt-hour of electricity per year from renewable sources. To achieve this, the company generates green electricity across the region through two wind farms, 16 hydropower plants, four solar parks, and two biogas facilities – and continues to expand its portfolio. For more information, please visit: www.suewag.com/erzeugung
maincubes is a European data center provider that develops and operates facilities in key markets including Frankfurt, Berlin, and Amsterdam. Its data centers deliver high security, certified sustainability, and flexible, customer-specific solutions. Using state-of-the-art technology, maincubes ensure uninterrupted availability for customers’ critical IT infrastructure. Clients include public sector organizations, national and international blue-chip companies, and global hyperscalers seeking sustainable, reliable, and high-performance digital infrastructure. Founded in 2012, maincubes is headquartered in Frankfurt am Main, Germany. For more information, please visit maincubes.com