Reliable, grid-independent power supply for data centers
Plenty of electrical energy and an uninterrupted power supply without fluctuations – these are the things data centers of all sizes need. To safeguard uninterrupted operation, system-relevant pieces of equipment are generally installed in duplicate so as to ensure the servers are available at all times. With their many system benefits, SOFC fuel cell systems offer an ideal solution for this challenging task.
Generating the power required by data centers directly on site in a decentralized way and independent of the power grid – that is a brand new approach on the market. This is the direction we are taking with the SOFC fuel cell systems we have developed. We are now testing them in our own data center, the Global Data Center in the Stuttgart region. In this pilot project, the fuel cell system with a power class of 100 kW is initially being used to power servers. Potentially, SOFC fuel cell systems could meet all the energy needs of a data center and even take over the power supply if there is an interruption to the grid supply.
Data from Bosch locations around the world comes into the Bosch Global Data Center round the clock. Giant rooms are packed with servers that loudly go about their work processing data, using it for calculations, and storing it. The annual energy needs of a three- to four-person household could be covered by the amount of power the data center consumes in one hour.
“Operations that require the highest level of computing power are running on the servers of our data center all the time. These include the simulation programs created by our research colleagues who are working on artificial intelligence and machine learning, which run for days or even weeks,” says Manuel Gayring, who looks after the technical infrastructure of Bosch data centers. He has been part of that team for three years. “Once one of these calculations is finished, the next one starts automatically. Our high-performance computers run round the clock seven days a week.”
Top priority: trouble-free operation at all times
How to build a data center of the highest availability class.
Walking through the power and server rooms in the Bosch Global Data Center, the first thing you notice is two colors – red and blue. The cables from the external main supplies run absolutely straight and are sheathed in either red or blue. Each server has two different, color-coded power supplies that are completely separate and do not cross anywhere in the building. “It is our team’s job to ensure the data center is available round the clock seven days a week – without the slightest interruption to the power supply and without any power fluctuations,” explains Manuel Gayring. “That’s why all system-relevant components are duplicated.” Contingencies are also in place in case there are faults on both electrical routes. During daily operations, the power supply is safeguarded using a flywheel storage device, which is a mechanical energy storage system. If the power supply is interrupted, the energy from the oscillating weight is sufficient to bridge the gap until a powerful diesel generator can start up and provide a secondary supply to power the entire data center.
The Bosch Global Data Center is certified to Level 3 availability class. This means all system-relevant components are in place at least in duplicate – also known as redundancy – and are independent of each other. A second data center, also certified to Level 3 availability class, is located at another Bosch site. The two data centers operate in a network – combined, they meet the requirements for Dual Site Level 4, the highest level of certification.
SOFC systems – the new solution for data center energy needs
The SOFC fuel cell systems we have developed provide an innovative means of supplying energy reliably and independent of an external grid. They produce electricity from gaseous fuels in an low-emission way, directly where they are in use, offering cost benefits. The development goal is to run them on green hydrogen, produced with electricity from renewable energies, in the future, thus making them efficient.
In the future and when scaled appropriately, SOFC systems can make data centers completely independent of the supply grids of external power companies:
- In a first stage of expansion, they can be used to provide primary energy to a data center, with the external grid only leveling out peak loads. At this stage, emergency systems such as diesel generators continue to provide the necessary level of redundancy.
- If additional SOFC systems are added, these can take over the work of leveling out peak loads. In this configuration, the connection to the external power grid only serves as a safety reserve in case there is any disruption to the primary supply.
- It is also possible to cover this reserve solely using SOFC systems. Installed in sufficient numbers, they can ensure an uninterrupted power supply, making the data center completely independent of external energy sources such as the energy grid or backup generators. When using green hydrogen, a data center supplied with energy from SOFC fuel cells can be operated on a efficient basis.
Putting it to the test
The aim of our pilot project is to provide practical evidence that integrating SOFC systems into data centers can meet the stringent availability and safety requirements of independent testing organizations. From the start of the project at the Global Data Center, TÜV IT was asked to certify each step and conformity with all safety standards.
The pilot fuel cell system at the Bosch data center is being part-funded by the German Federal Ministry for Economic Affairs and Climate Action as part of the 7th Energy Research Programme.
The biggest strength of SOFC systems as a solution for data centers is their scalability and flexibility.
100 kW plug-and-play systems as series products
To demonstrate the benefits of SOFC, we are initially integrating one 100-kW SOFC system, made up of individual SOFC fuel cell units, into the power supply system of our Global Data Center. Systems of this size are designed for future series production as prefabricated customer solutions. In data centers they can be scaled based on energy requirements. Sebastian Schmaderer, who is responsible for system engineering and scaling the SOFC pilot system at Bosch Research, explains the stages of the project: “At the start of the pilot project, we are using the SOFC system to produce electricity that we feed into the supply grid of the data center. In the second stage, we are emulating the load profile of servers – powering ‘quasi-servers’ with our fuel cell system as an isolated grid.” Schmaderer highlights the flexibility when choosing the location for units as one practical advantage of the technology. “It opens up new solutions when it comes to the redundancy required in the power supply for data centers,” he says. This could be, for example, two separate SOFC systems, each with a dedicated gas supply, being operated in different locations.
Good planning reduces investment outlay and operating costs
If the SOFC systems are installed near the server rooms, it is possible to minimize cabling and therefore also investment costs and line losses. The heat energy from the SOFC fuel cells can be made usable via heat exchangers. In water-cooled data centers, the higher temperature of the waste heat from the fuel cells can boost the lower-temperature waste heat from the IT systems so that service water or office spaces can be heated, for example. “When these factors are considered right from the planning phase of a data center, the SOFC technology can deliver its full range of benefits,” says Manuel Gayring.
Innovative solution for conservative applications
For the purposes of its use in the Global Data Center, the SOFC pilot system has been designed to safeguard its own permanent operational reliability as a closed system. The individual fuel cell units are being run in such a way that the overall system can compensate for the failure of single units. In this operating mode, the system ensures increased redundancy. After all, safety and guaranteed availability are the absolute essentials for the power supply in data centers. “With our pilot project, we are showing that innovative technological solutions can be used to implement even applications that have been planned in emphatically conservative ways,” says system engineer Sebastian Schmaderer.
Overview of SOFC at the Bosch Global Data Center
A 100-kW SOFC system is in operation at the Bosch Global Data Center. It is being used to test how the system copes with the demanding power supply requirements of a data center. The advantages of SOFC technology for data centers include independence from grid operators and flexible planning options for the systems.
Goal
Proof of the technology’s conformity with high availability standards.
Area of application
Decentralized, grid-independent power supply in data centers.
Location of use
Bosch location in the Stuttgart region, where data from Bosch locations around the world is processed.
The many practical benefits of SOFC systems open up new opportunities for building management, especially when it comes to planning new data centers.
- SOFC units installed at the data center
- kW electrical energy (nominal)
- Operational start of the first SOFC systems
The Bosch SOFC system is currently in the pilot phase. All technical specifications given are development objectives and refer to the beginning of life.
