Abstract: The invention relates to a device for recovering heat from the environment, for use in underground and underwater construction, wherein in a sheet piling wall (2) anchored in a subgrade and made of sheet piling wall elements (4) that can be locked to each other, the sheet piling wall elements (4) comprise at least one closed hollow space (6) designed as a heat tube (8), wherein the heat tube (8) transfers heat energy drawn from the water or the ground via the sheet piling wall elements (4) to a heat pump (16) via a heat exchanger (12) at the one end (14) of the heat tube (8).