Phase Change Material for Marine Holdover Plates

Holdover plates, as defined by the Refrigeration Parts Solution, are stainless steel tanks which contain an evaporator coil surrounded by a Phase Change Material called propylene glycol .  As the compressor runs, this solution freezes.  Once the compressor turns off, the frozen solution continues to absorb heat from the refrigerated box thereby extending the "off" cycle of the compressor.  When incorporated into a properly designed system, holdover plates can significantly reduce average energy consumption.

Phase Change Material as a safe substitute for Dry ice

Dry ice is generally used as a refrigerant for packaging and transporting food, pharmaceutical products and biological samples that are needed to be kept frozen. Dry ice is generally considered non toxic with an enthalpy of sublimation equal to 57 1 kJ/Kg which makes it a very effective coolant. Dry ice however is very dangerous if not handled with care. It's sublimation produces carbon dioxide vapors which is harmful in high concentrations and directly enhances carbon emissions. Direct contact with dry ice can freeze cells and give effects similar to burns. Phase Change Materials like PCM23N provide an advantage over using dry ice.