The following text has been machine translated from German.
The Pathfinder Programme of the European Innovation Council (EIC) targets “visionary, radically new” technologies capable of driving change, addressing global challenges, and creating entirely new markets. Its prestigious funding is a mark of research excellence. The EIC is now investing four million euros in a project led by elastocaloric pioneer Paul Motzki, in which his team at Saarland University collaborates with European partners. A completely new, climate-friendly cooling and heating technology originating in Saarland could establish itself worldwide.
Over the next three years, the project “SMACool” aims to develop a prototype air-conditioning unit for residential buildings. Fresh air will flow into homes through discreet, narrow ventilation slots in exterior walls and will be heated or cooled as needed until the desired comfort temperature for each individual room is reached. “We do not want to heat and cool houses using a central system, but rather to control each room individually and decentrally with our technology. To achieve this, we are developing a compact unit that incorporates our technology and could in the future be integrated directly into the mandatory ventilation systems of new buildings,” explains Professor Paul Motzki, who leads the SMACool project consortium. In addition to the researchers from Saarbrücken, the project involves the universities of Ljubljana and Naples (Federico II) as well as the Irish company exergyn.
In the context of climate change, the technology could become an alternative to conventional cooling and heating methods, which consume large amounts of energy and place a heavy burden on the climate and environment. “Elastocalorics functions both as a heat pump and a cooling system. It is more energy efficient and more sustainable than today’s climate technologies and operates entirely without climate-damaging refrigerants. The efficiency of elastocaloric materials is more than ten times higher than that of current air-conditioning or heating systems—they will require significantly less electricity,” explains Paul Motzki. “With the process planned in this project, we achieve temperature differences of around 20 degrees Celsius for both cooling and heating,” adds the expert in smart material systems. Both the U.S. Department of Energy and the European Commission have already identified this climate technology as the most promising alternative to existing methods. The World Economic Forum (WEF) has also just included elastocalorics in its Top Ten Technologies 2024 list.
The new heating and cooling method is based on a seemingly simple principle: heat is removed from or supplied to a room by loading (for example, stretching) and unloading a shape-memory material in the form of wires or similar structures. During this process, the material absorbs and releases heat. The Saarbrücken researchers use the superelastic nickel–titanium alloy for this purpose. Materials made from this alloy return to their original shape after deformation because they possess two crystal lattices, or phases, that can transform into one another. While water transitions between solid, liquid, and gaseous phases, both phases of nickel–titanium are solid—but one phase transforms into the other. During this transformation, the wires absorb and release heat. “The shape-memory material releases heat when stretched in the superelastic state and absorbs heat again when unloaded,” explains Paul Motzki, who holds a joint professorship between Saarland University and ZeMA, where he heads the research area “Smart Material Systems.”
The research team is now working to further develop the technology in terms of processes and design so that it can be practically installed in residential buildings. The challenge lies in constructing a device that operates in a closed-loop system in such a way that optimal cooling or heating effects are achieved as air flows past it. “Instead of the wires we have primarily used so far to develop the process, we will now use thin sheets of nickel–titanium, as their larger surface area allows them to absorb and release more heat,” explains Paul Motzki. The Saarbrücken researchers can build on extensive prior work: the new technology is the result of around 15 years of research in several multi-million-euro funded projects and in numerous award-winning doctoral theses. Professor Stefan Seelecke, Paul Motzki’s doctoral supervisor, is the founder of the “Smart Materials” research field in Saarland. Both work closely together at Saarland University and at the Center for Mechatronics and Automation Technology (ZeMA). The Saarbrücken teams have already developed, among other things, a heating and cooling demonstrator and a continuously operating refrigerator that demonstrates how elastocalorics can cool or heat air.
Two million euros of the EIC Pathfinder Grant will be invested in research and development at Saarland University. The engineers in Saarbrücken are investigating how a drive system can keep the sheets in continuous motion—working together with drive technology specialist Matthias Nienhaus and his team at Saarland University—as well as optimal airflow configurations, the most suitable shapes of nickel–titanium sheets, and the ideal loading and unloading forces required to achieve specific heating or cooling outputs. The team has also developed software that allows the heating and cooling technology to be adapted to different applications and enables the simulation and planning of cooling systems. In addition, they are researching the entire lifecycle—from material production and recycling to manufacturing. The SMACool project also involves Triathlon, the integrated ecosystem for entrepreneurship, innovation, and transfer at Saarland University, which provides support in communication, technology management, and commercialization strategy.
Background
The Top 10 Emerging Technologies report by the World Economic Forum (WEF) draws on insights from scientists and numerous other leading experts to identify ten technologies that will have a significant impact on society and the economy. “These emerging technologies are groundbreaking, attractive to investors and researchers, and are expected to reach significant scale within five years,” according to the WEF website:
https://www.weforum.org/publications/top-10-emerging-technologies-2024/
Shape-Memory Technology
The Smart Materials research team, founded by Professor Stefan Seelecke and significantly expanded together with Professor Paul Motzki in recent years, applies shape-memory technology to a wide range of applications—from robotic grippers to valves and pumps. Numerous doctoral candidates, and even students, are involved in researching this technology. It is the subject of many publications in scientific journals and is supported by several large research projects. Funding bodies include the European Union and the German Research Foundation (DFG). The Federal Ministry of Education and Research is investing more than €17 million in the DEPART!Saar project, in which researchers collaborate with scientific institutions and industry partners. The aim is to develop new technology transfer formats and accelerate the path to market.
To bring together the research community in this still relatively new field and to connect it with companies for practical implementation, Professors Stefan Seelecke and Paul Motzki founded the International Elastocaloric Society, which is being developed from Saarbrücken. To transfer intelligent material systems into industrial practice, the scientists have also founded the company mateligent GmbH.
Contact:
Prof. Dr. Paul Motzki, Chair of Smart Material Systems for Innovative Production
+49 (681) 85787-545; paul.motzki@uni-saarland.de
Franziska Louia, Head of Elastocalorics Group
+49 (681) 302-71364; franziska.louia(at)imsl.uni-saarland.de
Further Information:
https://smip.science/ – Chair of Smart Material Systems for Innovative Production
https://departsaar.de/elastokalorik – DEPART!Saar Project
Image: Sophie Lessure
