GEO-ENERGY is a term used to describe energy available from the Earth. For the ELREN scope only GeoThermal energy (GTe) shall be considered.

GTe can generally be divided into two forms:
a.  high temperature / deep GTe (HGTe)
b.  low temperature GTe (LGTe).

HGTe systems typically use the high temperatures available in the Earth's crust to produce hot water or steam directly. This can be used for space heating, process heating or electricity generation. Studies of HGTe resources have been carried out across the EU.
A sample of a geothermal map is this: Deep geothermal Map for Ireland (SEI, 2006)

Source: SEI (link)

LGTe systems normally imply the use of heat pump technology to upgrade the heat available and the typical application is for water or space heating. Heat pumps can draw their energy from the ground, water or air.

Again for ELREN scope only LGTe shall be considered and in particular the technology of heat pumps.

N.B. For basic information please refer to Chapter 4 - Geothermal Energy & Heat Pumps of the ELREN Training Manual available for download at this website homepage (leftside) upon registration (rightside).