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  • Databarn

The Customer


In 1999, Databarn Rivium B.V. & Databarn Amsterdam B.V. were founded by the company We-Dare. From 2015, We-Dare has separated, allowing Databarn to fully focus on data centre services. Here, customers can choose which data centre is most attractive with regard to location or the option of choosing both data centres through a dual solution.

The start
Our solution
The result
Our product

The Netherlands is full of data centers with outdated, energy-guzzling cooling installations on the roof. No longer necessary, because the latest cold water machines reduce energy consumption by tens of percents. Specialist STULZ uses outside air to save energy wherever possible.

This Monday morning, a large crane truck is needed to lift the 5,100 kilo cooling installation. But once he has the STULZ CyberCool 2 (CC2) chiller in his hoist, the colossus is on a purpose-built frame on the roof within ten minutes. The 'chiller' will soon keep the temperature in the various computer rooms constant via cooled water pipes to the server room. “With 400 kW, the capacity of this installation is a replacement of the current installation that Databarn previously has,” says Hans van Goor of STULZ on the roof of the data center on Zekeringstraat in Amsterdam.

Databarn is a company that offers various different customers space to house its servers. They are purring in the server room on the first floor and ground floor and thereby produce a lot of heat. Without cooling it could easily reach sixty degrees Celsius. A row of dozens of condensers on the circulation of the first floor prevents this. The disadvantage of this so-called DX cooling is that this system uses compressors in both summer and winter to cool the air in the computer rooms. “And the compressors are the main energy guzzlers of the system,” says Van Goor. “Our new Stulz CC2 installation does that very differently: with a separate energy-saving 'coil'. This ensures that if the outside temperature falls below a value, the server room is cooled with water that flows through it. ”

The CC2 installation already switches to a kind of energy-saving mode ("mixed cooling mode") when the outside temperature is a few degrees below that in the server room. In doing so, he partly uses free cooling. If the outside temperature drops further, the compressor cooling can switch off completely. With full cooling load at a temperature of 4 degrees Celsius, the compressors can even be switched off completely. The installation only runs on its large power consumers when it is warmer than about 21 degrees outside. Since this is only the case for a modest number of days of the year in the Netherlands - the average temperature in our country is 10.1 degrees Celsius - the potential profit is considerable. “In any case, dozens of percentages on an annual basis,” says Van Goor. "That is why the investment in the installation pays for itself within a few years."

To replace the existing twenty-year-old installation with the STULZ CC2 chiller, a few interventions are required at Databarn. First, a construction of steel trusses was mounted on the roof. It rests on the columns of the building. In addition, a new distributor has been built in with a primary and a secondary system. In the primary system, water goes back and forth between the chiller and the distributor via a return pipe. In the secondary system, a distribution pump, with the aid of a delta p controller, ensures that cooled water ends up in places where the temperature rises the most. The set-up with two separate systems makes it easy in the future to connect additional chillers if necessary. When the number of customers increases, Databarn can easily install a second installation on the roof.

Heat is disastrous for the sophisticated electronics in the servers, so cooling is essential for Databarn's business operations. In the server room, warm air that rises from the dozens of continuously running server units is extracted at the top and discharged to the computer rooms installed inside (air conditioning computer room). The installation on the roof has coils on the outside for free cooling. These are made of aluminum. Cooling water with glycol passes via micro channels through thin pipes with fins and is thus cooled by the outside air. A row of large fans on top of the installation provides the supply of air. The DX coils are located on the inside of the installation. The compressors connected to it use the refrigerant freon R410A. This part of the installation is switched on when the free cooling unit cannot bring the temperature of the water down sufficiently.

When the rooftop cooling process is complete, the cooled water returns to the server room through a piping system. A heat exchanger there cools the air that is passed along it. This is then blown back in via the raised computer floor. STULZ chose to carry out the transport of water via ABS plastic pipes. This prevents rust formation, among other things.

Originally from Germany, STULZ (3,500 employees) owns factories all over the world, but builds all its CC2 chillers in Hamburg. These are specifically intended for energy-efficient cooling of computer rooms. The installations are always designed to suit the customer. They can vary in size from roughly 400 kW to about 1400 kW cooling capacity. In Hamburg, the company also designs and installs the complete computer-controlled control technology itself.

STULZ builds the machines with extra large fans and a substantial package of sound insulation. As a result, they are low-noise, so that they can also be used in hospitals and near office spaces. Maintenance is easy due to the modular construction. If a part breaks, it is a matter of unscrewing and replacing.

The Netherlands is a hub for data centers, partly because a number of large cables for data traffic arrive at us. This makes our country an interesting market for STULZ's CC2 installation. “Of course that also has to do with our climate,” says Van Goor. “We have just had a warm period, so we easily forget that our average temperature is only around ten degrees Celsius. In a cold climate you can achieve even more energy gains with free cooling, but with us the potential is also enormous. In a time of energy-conscious building and working is actually a must. ”

CyberCool 2

The CyberCool 2 enables you to operate with maximum energy efficiency and optimum reliability for complex, demanding and uncompromising chilled water solutions. At the same time, the completely new overall concept of all components ensures low sound emissions in noise-critical applications. The result is a sustainable range of chillers that meets every eco-design directive.


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Databarn Amsterdam Case Study video


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