Description: Contemporary human space flight operations are limited to one to three years of shelf-stable food storage before resupply. Increased storage life of food is critical to support next-generation, human space exploration missions including the Lunar Gateway project and human exploration of Mars where resupply is unviable and unexpected delays must be accounted for. Air Squared’s innovative oil-free, liquid-cooled, scroll-based vapor compression system, the Zero-Gravity Vapor Compression Refrigerator (ZVCR), can preserve nutrition, extend storage life, and maintain quality and flavor by improving food storage life to five to seven-years. The ZVCR directly aligns with the Advanced Exploration Systems’ Logistics Reduction support of the Human Research Program goals on safety, nutrition, and crew acceptability for a long-duration, food system. VCC is not new to human space exploration. A VCC refrigerator and freezer was flown in STS-4 in 1982 and a refrigerated centrifuge was tested as late as 2005 but the latter failed soon after during the orbital operation. Since then, there has been little interest in VCC for space applications. Based on limited evidence, the decision appears to be made on the grounds of poor expected compressor reliability, concerns over maintaining oil-lubrication in microgravity, and the need for significant research and development required for a viable microgravity cold storage system. Interestingly, the majority of previous evaluations of VCC for space platforms have been hampered by strict on-board testing of orbital craft. Air Squared’s proposed Phase II-E seeks to expand understanding and confidence by demonstrating the reliability and performance of the ZVCR and its, oil-free scroll compressor by executing two, microgravity, parabolic flight tests. With support from two NASA agencies, a commercial refrigeration OEM and completed flight testing, the ZVCR will be advanced from TRL 6 to 7 and become well aligned for a future ISS demonstration.

Benefits: The ZVCR and the P09 oil-free, gravity-independent scroll compressor will support next-generation human exploration. Maintaining the nutritional value and taste of food beyond 5 years and reducing the logistical burden of space mission resupply is critical to the viability of long-term human space exploration. To that end, several human exploration initiatives including human habitation on the International Space Station, the Lunar Gateway, and future human exploration of Mars would benefit from a successful ZVCR development.

The oil-free, liquid-cooled P09 scroll compressor can upgrade aerospace and refrigerated transportation environmental control systems. By eliminating complex oil-circulation systems and maintaining optimal performance regardless of mounting orientation in dynamic environments, the P09 can reduce the size, weight, and power footprint over existing refrigeration compressors.