Costa Rica: Country Update Report

Abstract

Mirvalles geothermal field is being developed in the Guanacaste Volcanic Range of Costa Rica for electricity production as a complement to the vast hydroelectric resources of the county. Up to now five deep well shave been drilled, intercepting a reservoir with some 240°C mild saline fluid. Total electric power potential at the well head has been estimated at 23 MW (single flash) an 32 MW (double flash). Calcite deposition, which forms at the well flashing depth, will be removed by mechanical cleaning, with the well flowing, as is done in some fields in Iceland. It is estimated that the power cost from geothermal energy will be competitive with fossil fuel thermal plants and with hydroelectric energy costs.