Geothermal energy recovery from underground mines

Underground mines are extremely capital intensive, but despite this investment the traditional view has been that they have little useful value after closure. There are, however, potential positive uses of closed mines, in particular the generation of renewable geothermal energy. After closure, many mines flood and the relatively stable temperature of this water can be exploited by the use of geothermal recovery loops coupled to heat pumps. A review of the current situation, despite increasing pressures to identify sources of renewable energy, reveals that there are still only a limited number of existing and proposed installations. Nevertheless, a survey of those that do exist demonstrates the potential value of this approach. In particular, during the winter heat can be extracted from mine water and supplied for space heating, and in the summer the process can be reversed and the heat transferred back to the water to provide cooling.