The present application is related to a portable refrigeration apparatus for vaccines, food items, beverage containers, or any other item. The apparatus includes a refrigerated container comprised of a plurality of substantially identical chilling panels interconnected to form a sealed container that defines an internal volume, each of the chilling panels containing a cooling element. The refrigerated container encloses an internal storage space and has a generally modular design to facilitate packaging and transportation. The apparatus permits the internal storage space to maintain a temperature in the range of 4° C.˜8° C. for a long period of time following a loss of electrical power.