A system for storing thermal energy includes an opening into the earth, a liner positioned within and surrounding an interior periphery of the opening, a liquid provided within the liner, a first conduit fluidly associated with an upper portion of the opening, a second conduit fluidly associated with a lower portion of the opening, a fluid movement device and a heat transfer device. The fluid movement device is fluidly connected between the first and second conduits and configured to transport liquid between the first and second conduits. The heat transfer device is fluidly connected to the first conduit and the second conduit and configured to transfer heat to or from the liquid.