The Results of a Joint Scientific Study of the Flores Ulumbu Geothermal Area

Abstract

Indonesia' robust geothermal program has been gaining momentum in the last few years with the successful operation of Units 1, 2 and 3 at Kamojang and the planned developments at Darajt, Dieng, Salak and Lahendong. Many new areas have been investigated and preliminary drilling carried out to test scientific conceptual models and system productivities. The important of small mini geothermal developments, early recognized as having potential in the rural and more remote parts of the country, have maintained a prospective role in Indonesia's overall energy planning, with the ongoing investigations in Lahendong in Sulawesi, Kerinic in Jambi and Ulumbu on the island of Flores, East Nusa, Tenggara. Since the early volcanoloigical investigations in Flores made by Kemmerling (1929) to the geothermal investigations directed by Zen and Radja (1970) the island has been recognized as a source of heat and geothermal energy. Scientific exploration of a number of systems on the island was intensified in the 1980's and a concerted effort was directed towards Ulumbu, a geothermal area in Manggarai in western Flores. Much of the scientific work was carried out by VSI from their base in Bandung. During 1989 a decision was made to assess the technical and economic feasibility of setting up a small geothermal plant or approximately 3 MWe at Ulumbu. The study was funded by the New Zealand Government. This paper describes the geothermal investigations at Ulumbu in the period of 1980 until the present with particular attention to the nature of the resource and its potential for development.