Thermal energy storage system including a plurality of vessels each having hot and cold liquid portions separated by a floating piston

A thermal energy storage system for storing thermal energy produced by a heat source and for supplying the thermal energy to a thermal load, the thermal energy storage system comprising:

• a working fluid configured to store the thermal energy and transfer the thermal energy between the heat source and the thermal load;
• a plurality of vessels each configured to store the working fluid;
• each of the vessels having a first end, a second end, an interior region, and a floating separator piston located in the interior region to separate a hot portion of the working fluid towards the first end from a cold portion of the working fluid towards the second end;
• a first manifold configured to be thermally coupled to an output of the heat source and configured to be directly fluidly coupled to an input of the thermal load;
• and wherein the first manifold is fluidly coupled to the interior region of each of the plurality of vessels proximate the first end of each of the vessels;
• a second manifold configured to be thermally coupled to an input of the heat source and configured to be directly fluidly coupled to an output of the thermal load;
• and wherein the second manifold is fluidly coupled to the interior region of each of the plurality of vessels proximate the second end of each of the vessels;
• a temperature sensor proximate to the input of the thermal load for measuring the temperature of the working fluid entering the input of the thermal load;
• a controller configured to maintain the working fluid in a liquid state and to manage a temperature of the working fluid entering the input of the thermal load;
• wherein the controller is configured to, based at least in part on the temperature of the working fluid measured by the temperature sensor, selectively control movement of the floating separator piston in each of the plurality of vessels and fluid flow rate from each of the plurality of vessels in order to manage the temperature of the working fluid entering the input of the heat load.