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In Iceland geothermal water has been utilised since ancient times
for domestic purposes such as washing and bathing
as may be evidenced from place names, the Sagas, and early annals.
In the 18th century, research began into this energy source
and in 1946 the Icelandic government instituted systematic and comprehensive
energy research, which continues to this day.
The geothermal energy is not only suitable for space heating and electric production
it is used in green houses, fish farming, soil heating, snow melting
and even in space cooling and freezing.
Harnessing geothermal resources is a complicated process.
It requires a combination of technical and scientific expertise,
highly specialised equipment, sophisticated computer systems and practical know-how.
This is where Iceland GeoSurvey excels.
The development of a geothermal resource for electric power and hot water production
comprises in principle three phases:
*Resource identification, surface exploration and assessment.
*Siting and drilling of wells.
*Monitoring of reservoir and environment.
The hallmark of Iceland GeoSurvey is to develop technologies
that combine relatively low cost and high effectiveness.
Sampling of geothermal fluids in warm springs and boreholes is important.
Chemical analyses may yield an estimate of the likely temperature of the reservoir
and provides insights into boiling processes, flow paths and fluid origin.
Geologists produce detailed maps of the geothermal areas
covering tectonic and stratigraphic features.
Fracture zones that may provide flow paths for the geothermal fluid
are of particular interest.
Geophysical surveys yield important information about
the subsurface structure of geothermal systems.
They are used to map temperature distribution in the uppermost
parts of the crust as well as to detect up-flow of thermal fluid from the reservoir.
Monitoring of seismic activity indicates fracture zones at the depth
and gravity surveys can reveal other tectonic features.
Information about the stratigraphy of the geothermal reservoir is obtained by
drilling shallow exploration wells to gather data on the potential
temperature and geothermal gradient of the area.
Based on surface exploration and drilling, an estimate is made
of the reservoir’s area, depth and potential capacity.
Cross-interpretation of data obtained from surface studies and exploratory drillings
is used to site and design production wells.
The aim is often to cut a narrow geothermal fracture at a great depth.
Iceland GeoSurvey scientists carry out geological logging
and monitoring throughout the drilling.
Testing upon completion of the well includes measurements of down hole pressure
and temperature and determination of fluid chemical composition.
The results are used to construct a natural-state reservoir model.
The response of the reservoir to fluid production is assessed
by mathematical calculations and 3D modelling.
Such models help predict its short and long-term behaviour.
To sustain its pressure and yield, reinjection of the geothermal fluid is necessary.
This new technique establishes flow circulation
and aims at sustainable utilisation.
A geothermal production requires continuous and careful monitoring.
It involves metering net mass extraction, reservoir pressure
and temperature and chemical analyses to detect possible coldwater intrusion
and changes in properties of reservoir fluid.
Iceland GeoSurvey is committed to environmental standards
entailing systematic assessment of environmental parameters
such as liquid and gaseous emissions, subsidence and near-surface boiling.
Iceland GeoSurvey and its forerunners have been in the forefront
of geoscientific research development in Iceland
where 65% of the primary energy use is from geothermal sources.
For example almost 90% of all homes in Iceland
are currently heated with “the green” geothermal energy.
With laboratories, highly specialized equipment
and 60 years of experience in geothermal fields throughout the world
Iceland GeoSurvey’s personnel are well equipped to work
on every aspect to understand and utilise the Earth’s heat energy.
The company is committed to the promotion of geothermal energy,
both as a viable solution to the world’s energy needs
and as a contribution to its environmental well–being.
It actively participates in the dissemination of knowledge
about geothermal systems and in training of scientists
and technicians from around the world,
with emphasis on assisting developing nations.
Iceland has been called the earth’s most perfect geological laboratory.
There the planet’s inner workings are revealed accessible for study and experimentation.
This is a place where accumulated scientific knowledge has been applied
to harnessing the earth’s internal power.
Iceland GeoSurvey is an active participant in the development
and evolution of that endeavour.
Its experience and knowledge is a valuable asset
and has practical application throughout the world.