Stimulations are carried out in HDR/EGS systems so that the permeability between the
wells can be enhanced to allow fluid circulation to place to extract the heat energy
from the rock mass and transport it to the surface for power generation. This is done
to meet certain economic targets and therefore has to attain right characteristics to
minimize the parasitic losses during the circulation of fluid between the wells and
yet the system be large enough to support up to 70-100 l/s for approximately 20 years.  
Although one states that a stimulation is required to enhance permeability between
the wells (ie an injector and a producer), in actual fact there two distinct zones
which need to be addressed. The first one is near (the bottom) of the well and the
second is between the two wells.

CH-8532 Warth TG
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