| Abstract |
During the last five years the geothermal exploration in Chile has been very active due to the need for energy security. Chile has had to depend on imports to meet more than 75% of its energy requirements. At present detailed exploration studies are being carried out by fourteen private companies in seventy six concessioned geothermal areas. The investment budget for the exploration programs, including geosciences studies and the drilling of wells have reached nearly US$400 million. In the Northern Chile Geothermal Zone are about 90 hot-spring areas, and this zone has forty five exploration concessions being surveyed; the most advanced exploration programs have been done in the Colpitas, Apacheta, Pampa Lirima and El Tatio-La Torta geothermal prospects. Exploratory wells have been drilled in all of these areas, and the estimated combined power potential of exploitable geothermal energy of these four prospects is between 400 and 1,000 MWe. Exploitation concessions have been granted for the Apacheta and El Tatio geothermal fields, and the environmental assessment for the installation of a 50 MWe power plant has been approved for the Apacheta field; the construction of a power plant at El Tatio is pending for environmental worries. In the Central-Southern Chile Geothermal Zone there are about 200 hots-spring areas, and here thirty one explorations concessions are underway; the most advanced exploration studies have been completed at the Tinguiririca, Calabozos, Laguna del Maule, Chillán and Tolhuaca geothermal areas. Exploratory wells have been drilled in these prospects and the estimated combined power potential for the five areas ranges from 650 to 950 MWe. Exploitation concessions were granted for the Laguna del Maule (Mariposa) and Tolhuaca (San Gregorio) projects, where productions sized wells have been drilled. An environmental impact assessment was submitted to the authorities for approving the installation of a 70 MWe power plant in the Tolhuaca geothermal area, where the well Tol-4 has an output of 12 MW. In Chile, the electricity market is private and the state only has a regulatory role; the electricity system is structured by two major separated transmission grids; in the north and thee other in the central portion of the country. Currently, the installed electricity capacity is 16,325 MWe, with 38% supplied by hydropower, 60% by conventional thermal power, 1% by wind power and 1% by biomass. Due to almost null production of oil and gas in Chile, over 90% of the fossil fuels need to be imported and the cost of the electricity during these years has been around 100 US$/MWh. The Chilean government is trying to promote the development of non-conventional renewable energy (wind, solar and geothermal). There is now some growth in research funding for geothermal energy. The University of Chile has received a major grant to found the Andean Geothermal Centre of Excellence and the National Service of Geology and Mines is now developing a basic research program on geothermal resources. In spite of the great geothermal potential of the country, this energy has been an unexploited source for electricity generation and it is currently used only for recreational and touristic purposes. |