Geothermal Plant in Thisted with Absorption Heat Pump and 10 Years Operation Without Corrosion or Reinjection Problems in Sandstone for 15% Saline Water

Abstract

A geothermal pilot plant with an electric heat pump was erected by Dansk Olie og Naturgas in 1984 and expanded to the present demonstration plant with an absorption heat pump in 1988. The use of an absorption heat pump nearly eliminates energy consumption and operation costs for the heat pump. The absorption heat pump is by now driven by heat from a combined heat and power incineration plant and the driving heat is fully recovered on the district heating network. The design has made it possible to avoid corrosion problems and to reinject millions of cubic meters of a 15% saline geothermal water in a sandstone reservoir. Heat production costs, plant concept, operating experiences and absorption heat pump are discussed. The reservoir temperature at 1250 m is 46?C and the transmissivity Dm.