Eckelmann takes over central cooling control for high-performance data center in Mainz

The Customer

The first building of the data center is currently under construction next to KMW’s existing power plants and is scheduled for completion by the end of 2026. The full potential of the Mainz site will comprise three buildings with an IT capacity of 54 MW and a total output of 80 MW.

The data center will be powered by KMW’s wind and solar portfolio. The adjacent Rhine River serves as a sustainable cooling source for the servers and contributes to the data center’s enormous energy efficiency. The waste heat is fed into the existing district heating network via high-temperature heat pumps and benefits the city of Mainz. The data center is completely CO2-emission-free because the surrounding gas-fired power plants replace traditional emergency diesel generators.

The sustainability criteria at Green Rocks:

• Unique in Central Europe: KMW’s gas-fired power plants provide backup for the emission-free data center.
• Also unique in Central Europe: Waste heat is fed directly into Mainz’s existing district heating network.
• Another unique selling point: River water cooling from the Rhine.

Performance Eckelmann

Creation of hardware and software design specifications (HDS/SDS)

Automation & control:

• PLC programming with Siemens TIA Portal
• HMI programming with WinCC

Hardware scope of delivery per building:

• 2 master control cabinets manufactured in-house
• 18 RIO control cabinets manufactured in-house
• 3 HMI control cabinets manufactured in-house

User interface:

• HMI with process visualization, alarm management, and user roles

Integration:

• Interface to BMS/SCADA (monitoring only, Modbus TCP)

Key technical data per building

Cooling sources:

• 2x district heating feeds
• 2x Rhine water cooling, cooling capacity shared with the Mainz/Wiesbaden power plants
• 8x recooling units
• 8x cooling compressors

The Solution / Application

In order to dissipate the 60 MW of heat generated by the computers in three buildings, as much as possible is fed into the district heating network. The remaining heat must be cooled. The intelligent selection of cooling processes is based on external conditions and performance requirements.

In principle, several cooling sources are available for the cooling process:

• District heating
• The Rhine
• Cooling towers
• Machine cooling

The various cooling sources are activated according to this priority list.

To ensure maximum availability, Eckelmann provides redundant control and network topology.

• Software development and testing
• EOL testing and FAT at Eckelmann in Wiesbaden

• Commissioning and site acceptance testing (SAT)
• High redundancy: Redundant PLCs, networks, and control components

• High availability: Maximum operational reliability for critical IT infrastructure
• Fast control: Dynamic adjustment of cooling capacity for peak loads

• Scalability: Solution for future expansions