U.S. patent application 20190063765 (inventor Ray Arjomand, Sparks, Nev.)
"A refrigeration device has a condenser coil that has periodic access to outside air. A time-activated thermostat controls the operation of an evaporator coil that is in thermal contact with a reservoir containing phase change material. A thermally conductive pipe containing antifreeze fluid is connected to a pump that circulates the antifreeze fluid inside the pipe. A first portion of the pipe is inside the reservoir in thermal contact with the phase change material and a second portion of the pipe is near an air fan or connected to a fan coil unit to exchange heat through the pipe between the reservoir and the air blown by the fan or the fan coil unit. The evaporator coil produces a phase change in the phase-changing material in the reservoir at night when outdoor temperature is colder than during day and the phase-change material is used during day to cool air blown by the air fan or the fan coil unit."