On Monday, Norwegian data center company Green Mountain and German power company KMW, marked the start of construction of their new sustainable data center in Mainz, outside Frankfurt. Representatives of both local and regional government were present to perform a foundation stone ceremony at the site. The first 18MW building of the site, with 54MW total potential capacity, is set to be completed in Q1 2025. 

Earlier this year, Green Mountain and KMW announced they had partnered in a joint venture to build a new sustainable data center campus in Mainz, 30 km outside Frankfurt. The ground work at the site started in September, but today they officially marked the construction start. 

The Rhineland-Palatinate Minister for Climate Protection, Environment, Energy and Mobility, Katrin Eder, the Lord Mayor of the state capital Mainz, Nino Haase, and the Lord Mayor of the state capital Wiesbaden, Gert-Uwe Mende were all present at the event. Together with the management team of the joint venture, they placed relevant objects in a time capsule that was ceremonially placed in the foundation of the first building. 

Climate Protection Minister Katrin Eder, said “The green data center from KMW and Green Mountain is a lighthouse project for Rhineland-Palatinate that not only underlines the regional importance, but also paves the way for sustainable digitalization and economic development. It shows that we can also achieve our environmental goals through partnership-based collaboration and technical innovations." 

The site will be powered by 100% renewable energy, with gas turbine generators providing the backup power. The data center will be efficiently and sustainably cooled by the river Rhine and the waste heat produced will be fed directly into the existing district heating network of the city of Mainz.

CEO of KMW, Oliver Malerius, expressed his excitement about the project: "This data center, founded on a groundbreaking partnership with Green Mountain, is a symbol of technical excellence and sustainability. It shows how innovation and environmental protection can go hand in hand, and it fills us with pride, to help shape a green digital future."

A panel discussion with representatives of KMW and Green Mountain together with Anna Klaft from the German Data Center Association, Alexander Rabe from ECO and energy expert Staffan Revemann was the highlight of the program. They discussed important topics such as sustainability, developments in the market and energy efficiency. 

“This is truly a proud day in our company’s history. I am confident that this project will set a new green standard when it comes to data centers in Germany.”, CEO of Green Mountain, Svein Atle Hagaseth, concluded. 

Facts about the project: 

  • The power supply to the campus, that has a 54MW maximum potential capacity, will be covered by renewable energy.

  • It will be cooled by the adjacent Rhine River, making it very energy efficient with a PUE below 1,3.
  • The KMW gas plant will supply the back-up power, making diesel generators for emergency power redundant.
  • With a location close to the Frankfurt DE-CIX hub, strong connectivity is secured.
  • Up to 60 MW of waste heat will be fed into the Mainz district heating system, supplying 20,000 households, the dome and the stadium with renewable district heating.
  • The site can support both multi-tenant contracts as well as dedicated buildings for larger client installations.
  • Three data center buildings are planned at the new 25,000 sqm site situated in an already existing industrial area adjacent to KMW’s power plants.
  • Construction has already started and the first building will be completed in Q1 2025.