Costa Rica is located in the Central American isthmus, which belongs to the north, 10 degrees north latitude, longitude 84 degrees. East Caribbean, West The North Pacific There are 1290 kilometers, The coast line (212 km east of the Caribbean, the West Pacific 1016 km). In northern Costa Rica and Nicaragua The border (309 km long border line), south southeast border with Panama (639 km long border line). A total of 51100 square kilometers, of which the territory of 50660 square kilometers, 440 square kilometers of waters, than the America West Virginia A small, equivalent to Ireland. Forest coverage rate is 51%. Costa Rica's terrain: the coast is plain, while the central being isolated rugged mountains. The country declared its exclusive economic zone of 200 nautical miles territorial sea of 12 nautical miles. The climate is tropical and subtropical, some of it is new tropical.
The Miraval Les geothermal power plant in Costa Rica is depended on a source of volcano. Mira The Miraval Les geothermal field located in the Pleistocene crater. The Miraval Les volcano, is a after crater developed on the edge of the crater. Lithology in this area includes a series of volcanic rocks and volcano clastic band. High-temperature geothermal fluid produced in faults, the geothermal reservoir is mainly the formation of crystallization rock series tuff, andesitic lava, rhyolite tuff. The Miraval Les geothermal field drilling deep wells, such as PGM1,2,3,5,10,11,12 and 15, which can be used to analyze deep obtain temperature distribution of geothermal fields. In the west of the geothermal field of cold water intrusion, so west geothermal temperature drastically reduced, the south is gradually reduced, but the speed is relatively slow. At an altitude of -200m place, geothermal temperature reached the highest value, higher than 240 ℃.
Geological Map of Costa Rica
The development history of the geothermal power station
Between 1979-1980, in getting the Inter-American Development Bank (IDB) funding later, They drilled three exploratory deep wells in Miraval Les. These wells have shown, in the southwest slope of the volcano have a good liquid heat storage. 1984 to 1986, another six well drilling and testing is completed. In the PGM-01 exploration well was completed 15 years later, Miraval Les’s first generating units finally put into use. 1st generating units is a single flash 55MW generator, and in March 1994 began to run. Another single flash generator is installed in August 1998. The third is a 27.5MW generating units single flash generators, the generating units are private construction, provided that the signing of a power purchase agreement. The generators put into use in 2000. Recently a generator, the 5th generator, is a two-cycle two turbines generators into operation in April 2004.
The ground power system
The Miraval Les’s fifth generating units is just put into use in 2004. The generators use from the first, second and third generating units of waste brine, through injection wells to obtain a possible return to the heat reservoir of energy. Total generating capacity is 15.5MW, each electric power generating units are issued 7.75MW. Each power generation unit is composed of two turbines, drive the same generator. Cycle working fluid is a conventional n-pentane, C5H12. Each unit with two pre-heaters. Two evaporators with their own separate plate. Two regenerator, four water-cooled condenser. The generating units is provided by Ormat.