Schuberg Philis is an IT company with a datacenter located in Schiphol-Rijk, Amsterdam area. During the CATALYST research for heat reuse it became clear that just on the other side of the road of Schuberg Philis building is a large river water transport pipe. This pipe is for transporting river water to the coastal dunes. Before transport from the river intake point, the water is filtered and cleaned, but not to drinking water levels. The water will be infiltrated in the coastal dunes and after other filtering processes this water will be drinking water.

Can this river water pipe be used for free cooling of the datacenters? The short answer is yes, but it became clear that much more is possible. Combined with Asperitas immerged server cooling, heat pump heated buildings, ATES (Aquifer thermal energy storage) and CATALYST solutions a very flexible, energy efficient and environmentally friendly setup is possible.

In principle, the injection temperature of the river water into the coastal dune area is subject to an important restriction. The annual average warming up temperature difference of the river water, comparing intake temperature to dune injection temperature has to be limited to 3 degrees. This restriction basically leads to a one off application of the technique per river water transport pipe for a maximum free cooling capacity of approximately 20MW.

In case DC waste heat is reused in a pipe downstream facility, the free cooling potential further downstream is available again, allowing energy cascading. For permission purposes, not the intermediate pipe water temperatures are used, but the final injection temperature in the coastal area is determining permission, based on the 3K temperature difference rule. The 3K rule refers to the annual average warming up of the water, not to a momentary warming up of the river water.

If the river water is used just for free cooling, the setup below is a very robust solution. The ATES system is very reliable system which is a must have fore datacenters. It proven technology and used in several other datacenters in the Amsterdam region.


For application of CATALYST scenario 2, ‘Single DC Providing Heat’, the system can be extended with an additional heat exchanger, allowing DC waste heat reuse towards an external heat pump, for more energy efficient generation of heating and cooling.

This configuration can be applied, using traditional racks in the datacenters, with traditional chilled water temperatures. Already a very robust and energy efficient system, but more is possible.

If a DC is equipped with immersed server /racks like Asperitas, the return fluid temperature from the DC cooling system (a thermal oil) is approximately 55-60°C), then being able to provide DC waste heat reuse both with and without a heat pump. In that situation, even after the first waste heat transfer, the resulting river water return temperature is of sufficiently high temperature (being decreased from 55 to 35°C) for additional waste heat reuse (at connection provision).


This second heat reuse option (heat exchanger 4) does imply the connection to the external heat pump system, there allowing an energy efficient generation of heating and cooling.

The ultimate configuration for both DC waste heat reuse and IT load migration is a cascading / chained DC connection to the river water provision, being work load federated, all participating in an IT load migration pool, another part of the CATALYST solution.

The size of the Schuberg Philis datacenter is too small to provide sufficient waste heat. But the Schiphol-Rijk area has a lot of datacenters which potentially can be used as waste heat source. As Schuberg Philis we see the following benefits:

  • Applicable at various locations in NL, greenfield datacenters
  • Reliable system, climate proof
  • Beneficial system for datacenters > 5 MW net IT
  • After initial investment limited energy costs
  • Simple payback time ± 3 to 6 years
  • Low average PUE value achievable: ± 1,15
  • DC waste heat can be reused on high level, both on single DC level as on multiple, chained DC level downstream (energy reuse factor ERF > 90%)
  • Combination with IT load migration does offer additional flexibility options
  • Ideal system for energy cascading
  • Providing multiple CATALYST flexibility solutions

In case you want to know more about the system setup and CATALYST solutions please do not hesitate to contact CATALYST partners and/or SBP.

At a glance

  • No: 768739
  • Acronym: CATALYST
  • Title: Converting data centres in energy flexibility ecosystems
  • Starting date: October 1, 2017
  • Duration in months: 36
  • Call identifier: H2020-EE-2017-RIA-IA
  • Topic: EE-20-2017; Bringing to market more energy efficient and integrated data centres