Tompaso Geothermal Field: Early Monitoring

Abstract

Tompaso geothermal field is adjacent geothermal system apart of the Lahendong geothermal field which is the first commercially develop geothermal field in North Sulawesi by PT.Pertamina Geothermal Energy (PGE). Tompaso field is currently delivering steam to support 2 x 20 MW geothermal power plant. Even though both fields are part of Greater Tondano geothermal system, it has different characteristics than the Lahendong field. Tompaso is liquid dominated reservoir, with temperature ranging from 250 – 330 oC and fluid entalphy about 1000 – 1150 kJ/kg. Furthermore, the reservoir permeability of Tompaso field is higher compared to Lahendong and well-distributed on flatter terrain. The production of Tompaso field consists of 5 production wells in a single production cluster. The brine and condensate are injected into 4 injection wells which are separated to 2 (two) neighbouring injection clusters. The transient period of the field for the first year production are derived from pressure and production profiles. This paper is intended to present the history, characterization and early monitoring of Tompaso field