Indonesia’s geothermal push runs into local fears at Mount Ungaran

YOGYAKARTA, Indonesia — Neighbors of Mount Ungaran in Indonesia’s Central Java province have vociferously opposed plans to revive a geothermal power project, alleging it could jeopardize water supplies and agricultural livelihoods. This opposition follows a decision by the Ministry of Energy and Mineral Resources, in August, granting state-owned utility PLN authorization to conduct geothermal exploration and development at the volcano.

The genesis of local opposition against the project dates back to 2008, when the ministry first designated Mount Ungaran, an active volcano, as a geothermal working area. The recent decision has reignited a longstanding debate between the government and locals. Rahman, coordinator of the Semarang Menggugat Alliance (ASM), a group opposing the project, told Mongabay that the residents around Mount Ungaran rely on agriculture and local water sources, and they are apprehensive about potential impacts from the project.

“We can already sustain ourselves through farming,” Rahman explained, speaking in early September from Bawen subdistrict. “If geothermal development goes forward, we are concerned that our water sources could diminish or become contaminated, which would harm our agriculture.” The summit of Mount Ungaran, with Tanggul Lawang hiking trail in the background.

Image by Triyo Handoko/Mongabay Indonesia. Indonesia is situated in one of the world’s most seismically active regions, which endows it with substantial potential for geothermal energy generation—approximately 23.2 gigawatts, according to the latest figures from the Ministry of Energy and Mineral Resources. The ministry regards Indonesia as possessing the world’s largest geothermal resource potential, surpassing nations such as the United States and the Philippines.

However, the country’s cumulative installed geothermal capacity remains unspecified in the source material.