The Central America region has tectonic activity that produce an extensive
volcanic chain along the pacific rim. The first geothermal development was the
Ahuachapán field where a geothermal reservoir was discovered in 1968. The
commercial exploitation started in 1975 when two condensing units went on
line, the actual install capacity is 95 MW and the field still producing steam to
run the units. Another geothermal field in the area are Miravalles in Costa Rica
(1994), Momotombo in Nicaragua (1983) and Zunil in Guatemala went (1999).
In the region, the total install capacity is 8,890 MW with a maximum available
capacity of 7,300 MW, The peak load is 5,170 MW, with an average power
growth rate of 6%/year. The annual generation in 2005 was 34,272 GWh, with
2,500 GWh (7.3%) coming from geothermal power plants. Given the accelerated
growth rate of electricity demand and the oil price the region faces difficult
options to increase the supply of electricity in a near future. Most of the
countries in the region is considering as a national strategy the development of
indigenous sources of electricity like the geothermal.
In 2003, LaGeo and Shell did a hydraulic stimulations test in well TR-8 in the
Berlin Geothermal field as part of a project to explore the feasibility of
commercial hot fractured rock energy generation. During the pumping period
the level of the seismicity was much lower than anticipated and the pressure
growth as a function of the injected flow rate, the final injection capacity of the
well improve from 5 kg/s(24.5 bar) to 25 kg/s (18 bar). In 2005 LaGeo decided
to repeat the test for a long period of time (3 months/24 hours per day), the
results indicate that is possible to improve the injection capacity for long term
period using permanent high pressure (50 bar) pumping system
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