Full Steam Ahead: Indonesia’s Geothermal Giant Taps Volcanic Heat for a $79.6 Million First-Half Windfall

JAKARTA, Investortrust.id — Deep beneath the volcanic ridges of Sumatra and Java, superheated steam is driving a high-margin financial turnaround for Southeast Asia’s premier clean-energy generator.

PT Pertamina Geothermal Energy Tbk—trading on the Indonesia Stock Exchange under the ticker PGEO—reported a sharp acceleration in first-half earnings on Tuesday, capitalizing on aggressive capacity additions and high operational efficiency across its geothermal fields.

The company’s trajectory highlights a pivotal shift in Southeast Asia's energy landscape. As Indonesia—the world’s second-largest geothermal producer after the U.S.—strives to balance rapid industrial power demand with strict decarbonization pledges, PGEO's performance demonstrates that baseload renewable energy can deliver both stable power grid baseloads and lucrative equity returns without relying on heavily subsidized tariffs.

Financial results for the six months ended June 30, 2026, underscored that operational expansion: revenue climbed 14.7% year-over-year to $235.03 million, while net profit jumped 15.48% to $79.6 million.

Expanding Steam and Grid Delivery

The top-line surge was anchored by a 13.62% year-over-year increase in total electricity generation, which reached 2,745 gigawatt-hours (GWh) during the January–June period.

"This production surge was supported by robust contributions from nearly all PGE operating areas, including Kamojang, Ulubelu, Lahendong, and Karaha," Andi Joko Nugroho, Director of Operations at Pertamina Geothermal Energy, said during an online earnings call on Monday, Aug. 3, 2026. "We also saw a full-period contribution from the Lumut Balai Unit 2 geothermal power plant, which began commercial operations in late June 2025."

At Lumut Balai in South Sumatra, the activation of Unit 2 more than doubled the field's total power output. Meanwhile, at the flagship Kamojang asset in West Java, the completion of a make-up well pipeline in March 2026 added ~41 megawatts (MW) of steam capacity, matching elevated dispatch requests from state utility PT Perusahaan Listrik Negara (PLN).

At the Ulubelu field in Lampung, an additional ~35 MW steam supply from Cluster M came online in May 2026, further bolstered by optimized maintenance schedules. The Karaha field in West Java also yielded positive momentum through an targeted asset recovery program.

Outpacing Global Efficiency Standards

Beyond raw volumetric growth, PGEO logged asset reliability numbers that significantly exceeded international geothermal benchmarks.

For the first half of 2026, the company reported an availability factor of 99.71%, an unplanned outage rate of just 0.11%, and an average capacity factor of 90.42%. Most commercial geothermal operators worldwide run at capacity factors between 75% and 80% due to subsurface field decline and steam field maintenance overhead.

"The quality of our profit growth remains exceptionally high because the bulk of these gains stemmed directly from core operational performance, with non-operational factors offering only minor support," Fransetya Hasudungan Hutabarat, Chief Financial Officer of Pertamina Geothermal Energy, said during Monday's presentation.

Fransetya noted that bringing Lumut Balai Unit 2 online and adding new productive assets naturally elevated depreciation expenses, leaving the first-half gross profit margin at a healthy 55.5%. However, management views the upfront capital absorption as an essential trade-off to capture long-term annuity cash flows from long-term power purchase agreements (PPAs).

Looking toward the second half of 2026, executive management reiterated its commitment to reservoir management, preventive maintenance, and workplace safety as the company pursues sustainable capacity growth across its concession areas.