Computer center helps with university heating in Oldenburg

23.05.2024

Source: Energie & Management Powernews

The University of Oldenburg is now using some of the waste heat from its own data center for heating. This could save a good 100 tons of carbon dioxide per year.

The Ossietzky University of Oldenburg has implemented another energy-saving measure. It is one of the few universities in Germany to recover waste heat from parts of its computer center. The measure is part of the "Wärmewende Nordwest" project funded by the Federal Ministry of Education and Research (BMBF), which is headed by Oldenburg energy computer scientist Prof. Dr. Sebastian Lehnhoff. This could be a reference for future new buildings and renovations at other universities.

In the course of the project, several innovative cooling and heating systems are being installed at the university and intelligently linked in order to reduce energy costs and CO2 emissions. The first measure to be implemented is a heat recovery system for the university's new high-performance computing cluster, which will be installed in 2023. "The cluster's servers are cooled with water, as modern processors have an enormous power density," reports Meik Möllers, Head of Facility Management.

Heat for the swimming pool

The cooling water has a temperature of around 45 degrees Celsius when it leaves the cluster. This thermal energy is now used for heating: Using a high-temperature heat pump, the water is heated to 75 degrees Celsius and then fed into the university's heating network. This heat supplements the output of the combined heat and power plant on the Haarentor campus, which supplies buildings A1 to A15, the library, canteen and sports wing with heat.

"As the heat from the computer center is available all year round, it can be used to heat the university swimming pool, for example," explains Möllers. The annual amount of heat supplied by the heat recovery system is around 500,000 kWh. This corresponds to the heating requirements of around 30 four-person households or a saving of a good 100 tons of CO2 per year.

The other servers in the data center are air-cooled. A highly efficient compression refrigeration system was recently installed so that they can operate safely in future even at outside temperatures of more than 40 degrees Celsius. Thanks to these two measures, the university is already meeting the legal requirements of the new Energy Efficiency Act ahead of schedule. Coming into force at the end of 2023, it sets standards for the energy efficiency of data centers that will go into operation from 2026 for the first time.

2.8 million euros investment

The university invested 2.5 million euros from its own funds to bring the cooling and power supply of the scientific computers up to date in terms of energy efficiency, with a further 300,000 euros coming from project funds. Two further projects are already underway as part of the "Wärmewende Nordwest" project. Firstly, a ventilation system in the university library, which has been in operation since 1982, is being replaced. Here, too, much more efficient technology with heat recovery will be used in future.

The third project concerns the combined heat and power plant on the Wechloy campus. A so-called absorption chiller will use energy from the power plant's waste heat to generate cooling. This is needed in the science laboratories, for example to cool lasers or other equipment. Both measures are due to be completed in the autumn.

The aim of the overall project is to develop optimization strategies in order to operate the large-scale technical systems for heating, cooling, ventilation and power generation, which have so far mainly been operated in isolation, in a network and to link them intelligently. This is to be achieved by a building management control system with autonomous and semi-autonomous software agents. The project not only aims to optimize the campus's local heating network, but also to create additional flexibility for the regional energy market or the power grid, for example.

The project "Wärmewende Nordwest" is available on the Internet.

Author: Susanne Harmsen