Systems And Methods For Thermal Energy Storage

Abstract

In one embodiment, a thermal energy storage system includes a first cascade containing a first phase change material and a second cascade containing a second phase change material, wherein the melting point of the first phase change material is different than the melting point of the second phase material.

1 . A thermal energy storage system comprising:
 first cascade containing a first phase change material; and   a second cascade containing a second phase change material;   wherein the melting point of the first phase change material is different than the melting point of the second phase material.   
     
     
         2 . The system of  claim 1 , wherein the first and second cascades comprise first and second storage tanks and further comprising pipes that enable a heat transfer liquid to flow from one tank to the other tank. 
     
     
         3 . The system of  claim 1 , wherein the first and second cascades comprise first and second compartments of a single storage tank. 
     
     
         4 . The system of  claim 1 , wherein at least one of the phase change materials is contained within thermal energy storage capsules. 
     
     
         5 . The system of  claim 4 , wherein the thermal energy storage capsules comprise rigid capsule walls. 
     
     
         6 . The system of  claim 5 , wherein the capsule walls are spherical. 
     
     
         7 . The system of  claim 4 , wherein the thermal energy storage capsules contain a single phase change material. 
     
     
         8 . The system of  claim 4 , wherein the thermal energy storage capsules contain a non-eutectic mixture of multiple phase change materials. 
     
     
         9 . The system of  claim 4 , wherein the thermal energy storage capsules contain phase change material particles suspended within a liquid. 
     
     
         10 . The system of  claim 4 , wherein at least one of the cascades contains multiple types of thermal energy storage capsules, each type of capsule containing a different phase change material. 
     
     
         11 . The system of  claim 1 , wherein at least one of the cascades comprises a single phase change material in bulk. 
     
     
         12 . The system of  claim 1 , wherein at least one of the cascades comprises a non-eutectic mixture of multiple phase change materials in bulk. 
     
     
         13 . The system of  claim 1 , wherein at least one of the cascades comprises a piece of foam that contains a phase change material. 
     
     
         14 . The system of  claim 13 , wherein the piece of foam contains a single phase change material. 
     
     
         15 . The system of  claim 13 , wherein the piece of foam contains a non-eutectic mixture of multiple phase change materials. 
     
     
         16 . A thermal energy storage capsule comprising:
 a capsule wall that defines an interior space; and   a phase change material contained within the interior space.   
     
     
         17 . The capsule of  claim 16 , wherein the capsule wall is spherical. 
     
     
         18 . The capsule of  claim 17 , wherein the capsule has an outer diameter of approximately 1 to 2 inches. 
     
     
         19 . The capsule of  claim 16 , wherein the capsule contains a single phase change material. 
     
     
         20 . The capsule of  claim 16 , wherein the capsule contains a non-eutectic mixture of multiple phase change materials. 
     
     
         21 . The capsule of  claim 16 , wherein the capsule contains phase change material particles suspended within a liquid.