Improved performance of polyurethane foam insulation using Ingeo biopolymer liners and its impact on energy efficiency of refrigerator and freezers

This paper compares the effect of constant-temperature aging on the thermal conductivity of polyurethane foam in simulated refrigerator panels made from polylactic acid biopolymer from NatureWorks (Ingeo®) and high-impact polystyrene. Specimens were aged at room temperature and thermal conductivity measurements were made at 10°C over a period of 2.4 years. The energy use over the life of refrigerator and freezer is also calculated using the Energy-Efficient Refrigerator Analysis program developed by the United States Department of Energy to estimate the energy savings potential of various technology option upgrades (cabinet and refrigeration system) for rulemaking purposes. The results show that energy savings from implementing the Ingeo liner range from 818 to 1395 kWh (7.3 to 12.5% of total energy use) over a 15-year period.