Improving Energy Efficiency and Environmental Sustainability of Commercial Insulation

With increasingly stringent energy standards set in place by the Department of Energy, energy efficiency is becoming a paramount concern to manufacturers of appliances. Additionally, the production and disposal of the voluminous amount of polyurethane foam commonly utilized as insulation in refrigeration units poses a significant environmental challenge. In this context, this study investigated an alternative insulation for use in commercial refrigerator/freezer units. A prototype exploring the use of evacuated packets of pyrogenic silica substituting for conventional insulation was assessed. Assessment criteria included experimental comparison of heat transfer characteristics and the energy efficiency of the new insulation as well as its life cycle as it is related to environmental sustainability. Results indicate that in the new insulation design applied to the unit’s cover, heat flux decreased by an average of 36%, and energy efficiency improved by 5.1% over a 24 hour period. The new insulation design also resulted in improved environmental sustainability, resulting in a savings of 0.257 metric tons of CO2e over 20 years for a single unit. Results provide an alternative insulation design for use in commercial refrigerator and freezers, and a framework by which to assess the efficiency and environmental performance of similar products.