Carrier Transicold, a division of Carrier Global Corporation (NYSE: CARR) and a global leader in intelligent climate and energy solutions, is donating two NaturaLINE® container refrigeration units to Technische Universität Berlin (TU Berlin). The donation will support commercial-scale research into transcritical carbon dioxide (CO₂) refrigeration technology, contributing to the development of cooling systems that meet evolving environmental and regulatory requirements across the global cold chain.

Refrigerated containers, commonly known as reefers, are essential to international trade, transporting perishable goods such as food and pharmaceuticals over long distances. Most conventional container refrigeration units rely on synthetic refrigerants such as R-134a, which has a global warming potential (GWP) of 1,430. Under agreements like the Kigali Amendment to the Montreal Protocol and regulations such as the EU F-Gas Regulation, the refrigeration and shipping industries face phase-down schedules for high-GWP hydrofluorocarbons, increasing demand for natural refrigerant alternatives.

Natural Refrigerant with Lower Global Warming Potential

The NaturaLINE system utilizes natural refrigerant for refrigerated container shipping applications. CO₂ is a naturally occurring refrigerant with a GWP of 1, positioning it as a lower-GWP alternative to conventional synthetic refrigerants used in commercial cooling. In a transcritical CO₂ cycle, the refrigerant operates above its critical pressure, creating different thermodynamic conditions than conventional subcritical vapor-compression cycles. Enhancing the performance and efficiency of transcritical CO₂ systems across a broad range of operating conditions, particularly in high-ambient environments, remains a central focus of ongoing refrigeration research.

Hands-On Learning for Graduate Students

The Institute of Energy Engineering at TU Berlin will employ the NaturaLINE units as a practical learning tool for graduate students. Equipped with basic instrumentation, the units will enable students to measure temperature profiles, system pressures, and power consumption. This hands-on approach allows students to work directly with a real commercial system and gain firsthand insight into how transcritical CO₂ cycles differ from conventional refrigeration cycles.

Expanding Research Infrastructure

Beyond education, the units will become part of the institute's broader research infrastructure. Researchers intend to integrate and evaluate prototype components within the units to develop and test future heating and cooling systems, with performance assessed through automated test sequences. Long-term performance evaluations across various operating conditions are also planned to deepen understanding of commercial-scale transcritical CO₂ system behavior.

Industry and Academic Perspectives

"We are excited to have access to the next-generation technology embodied in Carrier Transicold's NaturaLINE refrigeration units in carrying out our research," said Professor Stefan Elbel, Chair of Heat Transfer and Heat Conversion, Institute of Energy Engineering at Technische Universität Berlin. "As regulatory requirements tighten and the industry moves toward more sustainable refrigeration solutions, advancing this technology is critical. We hope this marks the beginning of a long-term research collaboration with Carrier Transicold."

"Transcritical CO₂ systems are an important technology for our industry, and we are proud to support TU Berlin's Institute of Energy Engineering's work in this space," said Jean-Marie Carvalho, Vice President & General Manager, Global Container, Carrier Transicold. "By providing researchers with access to NaturaLINE container refrigeration units, we can help accelerate understanding of system performance, support future innovation and contribute to the development of more sustainable cold chain solutions."

Through this initiative, Carrier Transicold aims to advance the study of more sustainable refrigeration technologies for the connected cold chain.