Intelligent Heating with Supercomputer Waste Heat
The Jülich supercomputer JUWELS can solve highly complex computing tasks – and it gets quite hot in the process! In future, this waste heat, which is invariably produced during operation, will be used to heat the JSC and seven other neighbouring buildings on the campus efficiently and intelligently. This is made possible by a new low-temperature network, which is currently being developed in the "Living Lab Energy Campus" (LLEC) project to turn Forschungszentrum Jülich into a real-life laboratory. The aim is that with the aid of a new control platform, the areas of electricity and heat are integrated into energy generation systems that have a strongly fluctuating level of electricity production. This will help to save energy and reduce greenhouse gases.
Dr. Stefan Kasselmann, project manager of the LLEC explains how it works: “Through our system, we will direct the heated cooling water from JUWELS into an initial eight buildings close to the JSC computer room to heat the rooms there. To do so, we will be using parts of the existing local heat network as well as new piping systems. The precise design of the network has been tested using comprehensive simulations. The real innovation, however, is the integration of this heating network into the cloud-based control platform developed at IEK-10, optimizing the use of heat and electricity in the LLEC project’s overall energy system.”
Turning warmth into heat
The buildings are still currently heated by district heat from the Weisweiler lignite power plant with hot water at a temperature of around 110 °C. “The water that is heated by the supercomputers, however, only reaches a temperature of around 35 °C, which is too cold to supply heat to the surrounding buildings without any additional measures being taken,” explains Dr. André Xhonneux (IEK-10), LLEC team manager for simulation and software.
At first, heat pumps, which – to use a simple analogy – work in the exact opposite way to a fridge, reduce the temperature to the required 70 °C with the aid of heat exchangers. These instruments will be installed in the buildings as of spring 2021. “A new development is the integration of the heat pumps in the LLEC project’s overarching control system. The operation of these heat pumps is planned days in advance through special algorithms that are dependent on the expected use of the buildings, weather forecasts, and forecasts for the yield of photovoltaic electricity and waste heat produced,” says Xhonneux.
The entire system is scheduled to be up and running by the end of 2021. “This will not only help us to provide heating in a more climate-friendly way but we will also gain crucial insights into the optimal operation of such local heating networks. The developed solutions can then be transferred outside of Forschungszentrum Jülich in the near future to city districts.”
Keine Angst vor kalten Räumen
Aber was, wenn der Superrechner im Winter einmal keine Wärme liefert – etwa, weil er unvorhergesehen abgeschaltet werden muss? „Sollte JUWELS einmal nicht laufen, ist die Wärmeversorgung der Gebäude durch das Niedertemperaturnetz trotzdem gewährleistet, da in diesem Fall Abwärme aus der neuen Wärmevollversorgungszentrale automatisch beigemischt wird“, so Xhonneux.
Construction of the new, additional piping system has now begun. Roughly 920 metres of piping made of plastic-coated steel will be installed in the next few months. In the end, the network will be connected to the seven buildings of the JSC, IBI-7, IBG-3, and the Seecasino, as well as an eighth new multi-purpose building, which is still being built.
“Perhaps the biggest challenge with our low-temperature network is to set it up in existing buildings that are in use without significantly disturbing the colleagues working in and around these buildings,” says Philipp Ueberberg (B-TP2), head of the civil engineering team. No structural changes will be necessary in the offices themselves. “We will continue to use the radiator systems that are already in place,” explains Ueberberg. “We also want to avoid any road closures where possible and will look to close off as few parking spaces as necessary for as short a time as possible.”
“The most important goal for the low-temperature network is to demonstrate an efficient and intelligent system for heating buildings, in which the network is used as an active control component within the overall energy system,” says Dominik Hering, a doctoral researcher in the field of mechanical engineering at IEK-10. “Intelligent in this scenario means establishing as optimal a balance as possible between the generation and demand of heat and electricity.” This will help to save a lot of energy and significantly reduce CO₂, he adds. “If the supercomputer runs for a long time without interruption, this could be a reduction of up to 320 tonnes of CO₂ per year in comparison with a conventional district heating supply,” Hering says.
A component of the energy transition
n Germany, the heating of buildings makes up around 28 % of the annual final energy demand, Xhonneux explains. “At more than 75 %, fossil fuels make up a very large proportion of household energy demand. Using existing waste heat in such an intelligent fashion – i.e. via local heating networks – for the heating of rooms can thus help to significantly reduce the use of fossil fuels.” With a centralized heat source, heat can be produced efficiently or – using the example of Jülich’s supercomputer – waste heat can be used sustainably. The project is funded by the Federal Ministry for Economy and Energy (BMWi).