A geothermal energy rights concession, located 14 kilometers southwest of Guatemala City, was awarded to U.S. Geothermal Guatemala S.A., a wholly owned subsidiary of the Company in April 2010. The concession has a five year term for the development and construction of a power plant. There are 24,710 acres (100 square kilometers) in the concession, which is at the center of the Aqua and Pacaya twin volcano complex.
Production well EC-5 was completed to a depth of 1,450 feet (442 meters) on August 20th and intersected a high permeability zone at 1,299 feet (396 meters). EC-5 underwent a series of flow tests, with field wide monitoring, beginning on September 5th and ran until September 13th. Data was collected from three monitoring wells during the test (EC-2A, EC-3, and EC-4) to provide pressure data for the reservoir model. Fluid samples taken at the end of the flow test indicate a potential reservoir temperature of 450 to 523°F (232 to 273°C).
With the shallow, commercial resource now proven, a deep well is planned in 2017 to test the producing structure down dip from well EC-5 to a projected depth of 1,970 to 2,300 feet (600-800 meters). EC-5 was completed to a depth of 1,450 feet (442 meters) and intersected a high permeability zone at 1,299 feet (396 meters) with a temperature of 388°F (198°C). Chemical analysis of fluid samples taken from EC-5 at the end of a flow test indicate a potential, deep reservoir temperature of 450 to 523°F (232 to 273°C). A deeper intersection in the reservoir could increase the reservoir capacity and production temperature, and change the design of the power plant. Well EC-1, which was drilled in 2013 to a depth of 5,650 feet (1,722 meters) found a measured bottom-hole temperature of 526°F (274°C), but did not intersect permeability. The comparative geology between EC-5 and EC-1 suggests a fault or other structure feeding the reservoir may be located in the area between the two wells.
On January 10, 2017, the Guatemalan government, through the National Electrical Energy Commission (COMISIÓN NACIONAL DE ENERGÍA ELÉCTRICA–“CNEE”), announced that it is preparing to issue an RFP later this year for 420 megawatts of power, of which 40 megawatts is to be reserved specifically for geothermal energy. When the RFP is issued, the El Ceibillo project will be bid into the process.