The invention discloses a multi-structure coupled long-period soil heat storage device, and belongs to the technical field of
renewable energy storage. The device comprises a cylindrical soil heat storage body, a short-term heat storage water tank, a high-temperature water distribution and
collection system and a low-temperature water distribution and
collection system. The soil heat storage body is divided into a central area, a middle ring area and a
peripheral area in the radial direction, shallow-layer heat storage wells of a U-shaped
pipe structure are arranged in the central area and the middle ring area, middle-deep-layer heat storage wells of a coaxial sleeve
pipe structure are arranged in the
peripheral area, and the
layout with the dense inside and the sparse outside is formed. The high-temperature water distribution and
collection system preferentially guides a high-temperature working medium into the heat storage wells in the central area and the
peripheral area, and the low-temperature water distribution and collection
system guides a low-temperature working medium into the heat storage wells in the middle annular area, so that a high-low-high temperature field gradient is actively constructed underground. According to the structure, the heat
shielding effect is formed through the peripheral low-temperature area, the top face heat preservation plate is combined, radial and upward
heat losses are effectively restrained, and the cross-seasonal heat
storage efficiency is remarkably improved.