Energy efficient cold storage units

An apparatus comprising:

• a cold storage unit capable of being connected to a power grid, comprising:
• a refrigeration system;
• a box enclosing an interior space, the box comprising a plurality of insulating sides, the insulating sides minimizing heat transfer and moisture transfer to the interior space from an external environment, the plurality of insulating sides providing insulation of rating about R-68 or greater;
• an entry into the interior space comprising a plurality of openable barriers, the plurality of barriers facilitating preventing entry of heat or moisture into the interior space from the external environment;
• a power system connected to the refrigeration system, the power system facilitating independent operation of the refrigeration system when not connected to the power grid, and further facilitating a net energy use of zero from the power grid when connected to the power grid;
• and
• a plurality of tubes facilitating conveyance of a refrigerant within said refrigeration system to a drain pan, the drain pan facilitating collecting and removing moisture from an evaporator, and wherein the refrigerant facilitates preventing freezing of moisture in the drain pan.