Julio Palma and Alfredo René Roldán Manzo
EMPRESA DE GENERACIÓN DE ENERGÍA ELÉCTRICA
INSTITUTO NACIONAL DE ELECTRIFICACIÓN –INDE-
INDE has five geothermal areas in reserve to develop, they are: Zunil, Amatitlán, Tecuamburro, San Marcos and Moyuta and is also working in Totonicapán.
Figure 1. GEOTHERMAL AREAS OFINTEREST
In Zunil I there is actually a 24 MW binary cycle geothermal power plant in production. In Amatitlán geothermal field, a backpressure power plant of 5 MW will produce during 2003 and 2004, in the meantime a 50 MW modular plant will be installed.
The 5 MW backpressure power plant will be moved to Zunil II geothermal field in 2005.
For the near future, pre-feasibility studies willcarried out in Tecuamburro, San Marcos, Moyuta and Totonicapán fields.
Research of geothermal resources in Guatemala start en 1972, using for that INDE´s funds
and finance from International Development Bank IDB and Organization of Petroleum Export Countries OPEC, there had been also technical and financial cooperation from Latin American Energy Organization (OLADE), ROCAP/AID,European Community, Japan International Cooperation Agency (JICA) and the International Atomic Energy Agency (IAEA).
The first studied area was Moyuta (Location 12, figure 1, 1972), where there were geothermal manifestations which characteristics showed high probability to use the resource for electric power generation. In 1975 two commercial diameter exploratory wells were drilled founded,unfortunately, temperature reversal. Due to this fact the research was focus in the Zunil field and later on in Amatitlán (Location 2 and 5, figure 1).
With the objective of to have a national inventory of geothermal resources and to have a better understanding to define the most promissory areas for investigation, in 1981 INDE and BRGM of France, with INDE´s funds and donation from OLADEcarried on recognize studies at regional level in 13 areas (Figure 1) located along the volcanic chain that is to the south and crosses the country from east to West, from El Salvador border to the Mexico border, covering around 30% of the national land.
These studies showed that to the Zunil and Amatitlán areas, at that time as first priority, the areas of San Marcos, and Tecuamburro must beadded. In priority order follows Los Achiotes in Santa Rosa province, Moyuta in Jutiapa and Ixtepeque-Ipala in Chiquimula. In third category, Palencia, Retana, Ayarza, Atitlán and Motagua were classified. In 1993, with the technical cooperation of the International Atomic Energy Agency –IAEA- the Totonicapán geothermal area was also identified as priority area.
GEOTHERMAL STUDIED AREAS
Theareas studied up to the level of prefeaseability and feasibility and that has wells (slim holes or commercial wells) are showed in Figure 2.
ENERGY PRODUCTION IN THE PAST
With the purpose of make useful the available resource in Amatitlán geothermal area, at the middle of 1997 INDE approved the consultant service to “Evaluation of the field under production and exploitation of the existingwells”. The contract included installation of a back pressure power plant with 5 MW capacity, which will produce by 3 years from November 1998, producing 35 GWh/year ending that contract in November 2001.
Parallel during 1997, INDE asked for not reimbursable cooperation from the Japanese government, through JICA, to evaluate the extension of the Amatitlán field, including one or two deepcommercial diameter exploratory wells, complementary studies have completed and the two wells were drilled; the evaluation of those wells gave a total production capacity of 7 MW.
In Zunil I Geothermal field, considering that there was enough capacity to produce up to 25 MW, Inde made a bid process to install a geothermal power plant in this area and at the end of 1993 Inde signed a contract with...