A team of researchers at Saarland University and the Center for Mechatronics and Automation Technology in Germany has developed an innovative air conditioning technology that uses the “elastocaloric effect” in nickel-titanium (Ni-Ti) shape memory alloys to cool and heat without using volatile refrigerants or burning fossil fuels. This technology, known as elastocalorics, is regarded as a leading alternative to traditional cooling systems by the EU Commission and ranked among the World Economic Forum’s “Top Ten Emerging Technologies” in 2024.
The elastocaloric effect occurs when the material is repeatedly deformed, allowing it to absorb and release heat. By exploiting this property, the researchers have designed prototypes that use Ni-Ti wires or sheets to efficiently move heat from one place to another, achieving higher energy efficiency and minimizing environmental damage.
The technology has received significant attention, with government and industry stakeholders, including Volkswagen and the Fraunhofer Institute, collaborating on applications for electric vehicles, residential buildings, and more. With an investment of over €17 million and an additional €3.5 million in government funding, the technology is moving towards commercial viability.
The first prototypes are being developed for a lightweight air-conditioning unit for electric cars, a system to cool EV traction batteries, and a compact version for residential buildings. Initial trials show that single-stage elastocaloric components can achieve temperature differentials of around 20°C, with multi-stage solutions offering even larger deltas.
The team’s progress builds on 15 years of research, which has yielded the world’s first continuous air-to-air elastocaloric prototype and the first elastocaloric mini fridge. The technology has the potential to reshape the industry, offering a path towards more sustainable heating and cooling solutions for homes, vehicles, and beyond.