Magnetism instead of compression

How do you cool a steadily warming planet in an environmentally friendly, safe and efficient way? For MagnoTherm Managing Director Max Fries, the answer is clear: “We need to move away from gas.” Asked about the significance of the new cooling unit, whose prototype his team is currently preparing for the first integration tests, the materials scientist delves a little further into the history of an industry in which little has changed in terms of basic technology for more than a hundred years. After all, the cooling industry still largely relies on compression cooling today. The problem: This process relies on gaseous refrigerants, all of which have serious disadvantages. Starting with the explosive natural gases such as propane, butane or CO2, to the artificial gas CFC, which destroys the ozone layer, to its successor HFC, which exacerbates the greenhouse effect.

By now, the EU requires that CFCs and HFCs be reduced in many sectors by 2030. Faced with supply bottlenecks and cost increases, the industry is once again using the same natural refrigerant gases as in the 19th century, while accepting the fact that they are difficult to handle and also reach their limits in terms of energy efficiency. “There has not been a real paradigm shift so far”, says Fries. He and his business partners, physicists Dimitri Benke and Tino Gottschall, materials scientist Professor Oliver Gutfleisch and industrial engineer Timur Sirman, now want to help drive this forward with their new technology and the corresponding products. Both are based on the principle of magnetocaloric cooling. The bulky term stands for a process in which instead of a gas, cooling is provided by a solid material that can be quickly heated up and cooled down again via targeted magnetisation and demagnetisation. After many years of basic research, including in the Functional Materials Division at TU Darmstadt, a mixture of materials has proven to be ideal for this purpose: Lanthanum, iron and silicon, or LaFeSi for short.

LaFeSi is cost-effective, energy-efficient and powerful – but making it usable and getting it “into the machine” is a challenge. The research team at TU Darmstadt, led by Oliver Gutfleisch, has succeeded in refining the alloy in such a way that it can be integrated into a commercial refrigerator. And only three years passed between the filing of the patent application for the corresponding technical process and the founding of the company. The founders quickly recognised the “radically innovative” character of the new invention and its potential. The advisors from the HIGHEST Innovation and Start-up Centre at TU Darmstadt took the scientists, who had a business idea but little experience of how to finance and implement it, under their wing, coached them in the further development of their business model and taught them what entrepreneurial thinking means. Together with HIGHEST, the team of founders secured the first round of funding through a three-year EXIST research transfer grant, which MagnoTherm Solutions will continue to receive until the end of 2021.

The award-winning start-up wants to occupy a niche in the refrigerator market for the time being. The “refrigerated display” – an open chiller cabinet that can simply be plugged into a power socket – is a product for the retail trade. Others, for example air conditioning, server and transport cooling, are to follow. “Our technology is safe and forty percent more efficient than the best solution currently available”, says economic expert Sirman. But despite all the successes so far: The pressure to deliver a marketable product remains high. “We are chipping away at many blocks at the same time and new challenges emerge every day”, says technical director Benke, describing the ups and downs. But the young entrepreneurs have trust in the competitiveness of their company. This is mainly because they “not only fully understand the material, but also know how to build good refrigeration machines”. Negotiations with venture capitalists for EXIST funding are already underway. The team and its competences are growing steadily. Things are looking good for MagnoTherm Solutions GmbH. Almost twenty percent of the world's energy demand is already used for cooling. In forty years, experts estimate, mankind will have to spend more energy on cooling than on heating. Reason enough to keep at it. The first small series of the cooling display is to go into production in two to three years.