Geothermal power station has deep vertical shaft filled with a first good heat conductor and a second thermally insulated section

摘要

A geothermal power station consists of a deep vertical shaft into the earth through which runs a U-shaped pipe from surface to surface. The first part of the pipe is packed within a material which is a good heat conductor. The last part of the pipe (25) above an inversion layer (Zi) is surrounded by material (50) which is a poor heat conductor. The incoming pipe conveys a cold fluid e.g. brine through the first sections of the pipe as it is progressively heated. On rising above the inversion layer the insulated pipe promotes retention of geothermal heat within the brine. On arrival at the surface, the hot fluid surrenders heat energy to a heat pump. Further claimed is a suitable construction process.