Modular ice storage for uninterruptible chilled water

A backup cooling storage system comprising:

• at least one cooling and storage unit configured to cool a liquid supply using a quantity of cooled material when a main chiller of the liquid supply is not operational;
• and
• at least one chilling element configured to generate the quantity of cooled material for the at least one cooling and storage unit when the main chiller of the liquid supply is operational,
• wherein the at least one chilling element is configured to generate and maintain the quantity of cooled material so that at least a predetermined amount of the quantity of cooled material is frozen,
• wherein the at least one chilling element includes a cooled material monitoring element configured to monitor a current amount of the quantity of cooled material that is frozen, and
• wherein the cooled material monitoring element includes an aeration device submerged into the quantity of cooled material from above and configured to release a gas bubble into the quantity of cooled material, and wherein the cooled material monitoring element is configured to determine the current amount based on a pressure used to release the gas bubble into the quantity of cooled material.