The university's central library has been fitted with a new, particularly efficient ventilation system. The measure is part of the "WärmewendeNordwest" project funded by the Federal Ministry of Education and Research.
They run 365 days a year from six in the morning until midnight, moving up to 100,000 cubic metres of air per hour: the more than 40-year-old ventilation systems in the University of Oldenburg's Central Library have now been refurbished. The measure is part of the "WärmewendeNordwest" project funded by the Federal Ministry of Education and Research (BMFTR), which is headed by Oldenburg energy computer scientist Prof Dr Sebastian Lehnhoff. As part of the project, a total of three innovative cooling and heating systems have been installed at the university - in addition to the library's new ventilation systems, a so-called absorption cooling system on the Wechloy campus and a system for waste heat recovery in the Data Centre.
"As with other state institutions, there is a massive refurbishment backlog at our university. At the same time, we have to make a contribution to Lower Saxony's goal of climate neutrality. As a university, we are striving to be climate-neutral by 2030. To achieve this, we need our own creative solutions and, above all, funding," explained Jörg Stahlmann, Vice President of Administration and Finance at the university, at the inauguration. "Thanks to WärmewendeNordwest, we have finally succeeded in carrying out the urgently needed renovation of the library's ventilation systems and also making this central building fit for the future," emphasised the Vice President.
The refurbishment will significantly reduce the library's energy consumption for ventilation: the demand for electrical energy will be reduced by 17 per cent, while more than three quarters of the energy previously used for heating will be saved thanks to the recovery of waste heat. The university is thus reducing its overall energy consumption by around 2.1 per cent and fulfils the requirements of the Energy Efficiency Act through this measure alone. The law, which will be passed in 2023, obliges public bodies to reduce their energy consumption by two per cent every year. The construction project cost around 3.5 million euros in total. Around 2 million euros of this came from funds from the WärmewendeNordwest project, while the university financed the remainder from its own funds as part of an intracting model. It uses reserves - i.e. budget funds that will only be needed at a later date - to realise investments in energy-saving measures, for example. The funds saved in this way during ongoing operations flow back into the university's budget as soon as a measure has been amortised. In the case of the new ventilation system, the energy costs saved amount to around 175,000 euros per year. The refurbishment was planned and carried out by Staatliches Baumanagement Region Nord-West and the engineering firm Ahrens GmbH from Oldenburg.
New absorption chiller
As a second measure within the WärmewendeNordwest programme, the university recently put an absorption chiller into operation. This utilises previously unused waste heat from a combined heat and power unit as energy to generate cooling for scientific laboratories. The system helps to optimise utilisation of the combined heat and power plant, particularly in summer, and to meet the university's increased demand for cooling. The use of the new machine saves almost 150 tonnes of CO2 emissions per year compared to the compression chillers previously used. The university can save operating costs of around 150,000 euros a year thanks to the more favourable production of cooling as well as the additional electricity generated by the combined heat and power unit.
Heat recovery in the Data Centre
Last spring, the university put a heat recovery system into operation at the high-performance computing cluster installed in 2023. The thermal energy from the water-cooled servers is used for heating and fed into the university's heating network. With this process, the University of Oldenburg is taking on a pioneering role nationwide. "Even without heat recovery, our scientific computing is already very energy-efficient, but heat recovery increases efficiency even further," emphasises Meik Möllers, Head of Building Management. Data Centres typically require just as much energy to operate infrastructure such as lighting, air conditioning or cooling as they do for the IT equipment. At the Oldenburg Data Centre, this figure is only 13 percent - an excellent value. The amount of usable heat in the first year of operation exceeded the original forecasts by 40 per cent, which enabled further savings in heating. The energy generated would be enough to supply 40 four-person households with heat.
The three completed measures are part of the "WärmewendeNordwest" project, which is part of the "Experimental Campus Digitalised Heat Transition at the University of Oldenburg" work package led by Ekaterina Lesnyak from the Department of Computing Science. The aim of the project, which will run until November, is to develop optimisation 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 optimise the campus's local heating network, but also to create additional flexibility for the regional energy market or the electricity grid, for example. The overall project is being coordinated by OFFIS - Institute for Computing Science, an affiliated institute of the university.
The energy-efficient refurbishment of buildings and the supply of renewable energy are two important building blocks on the university's path to becoming climate-neutral by 2030. Last year, for example, the university renovated the energy efficiency of the glass façade of the main building on the Wechloy campus and achieved a total output of one megawatt by expanding the photovoltaic systems.
