Description:
Some proponents of geothermal energy have described
this energy source as renewable, but many geothermal fields
show declines in output as exploitation proceeds. On the
other hand, those who would call geothermal a depletable
energy source have to explain how some mature fields are
able to produce with negligible declines and no apparent limit
to the amount of recoverable energy.
The confusion arises out of the attempt to describe
geothermal resources using inappropriate conceptual models
of how resources behave. This paper presents a conceptual
model that is better suited to describe the expected
performance of a geothermal field over its entire life cycle.
The paper also describes a set of terms that can be used to
quantify geothermal resources and to guide plans for
development.
