Иностранный язык (английский) - для технических специальностей

     Geothermal energy is based on the fact that the earth is hotter the deeper one drills below the surface. Water and steam circulating through deep hot rocks, if brought to the surface, can be used to drive a turbine to produce electricity or can be piped through buildings as heat. Some geothermal energy systems use naturally occurring supplies of geothermal water and steam, whereas other systems pump water down to the deep hot rocks.    Although theoretically limitless, in most habitable areas of the world this bottomless energy source lies so deep that drilling holes to valve it is very expensive.