Patent ID: 7971437

Claim:
The thermal energy storage apparatus comprising: a phase change medium; an inner manifold area having at least one inner feed port; an outer manifold area having at least one outer feed port and fluidically coupled to the inner manifold area; at least one intermediate manifold area; a first plurality of U-tubes coupled between the outer manifold area and the at least one intermediate manifold area; and a second plurality of U-tubes coupled between the at least one intermediate manifold area and the inner manifold area; wherein the outer manifold area surrounds the inner manifold area, and wherein the inner manifold area and the outer manifold area are configured to be substantially immersed in the phase change medium, and wherein the inner manifold area is fluidically coupled to the outer manifold area via the second plurality of U-tubes, the at least one intermediate manifold area, and the first plurality of U-tubes.