Mitsubishi Power Completes Retrofit of Darajat Geothermal Power Plant in Indonesia
-- Power Output Increased by 8 MW, Commercial Operation Commenced --

Completion ceremony and agreement signing ceremony

Tokyo, October 20, 2026 - Mitsubishi Power, a power solutions brand of Mitsubishi Heavy Industries, Ltd. (MHI), has completed the retrofit of Unit 3 at the Darajat Geothermal Power Plant in Indonesia, owned by local geothermal power producer Star Energy Geothermal Darajat II, Limited (SEG), and commenced commercial operation. The renovation has increased the power output from 121 megawatts (MW) prior to the retrofit to 129 MW, making it the largest single-unit geothermal power unit in Indonesia. Geothermal power is a renewable energy source with extremely low CO₂ emissions during operation, and this retrofit contributes to Indonesia's decarbonization efforts and increases its renewable energy ratio.

The retrofit project involved a partial upgrade of facilities using steam turbines manufactured by MHI's Nagasaki Shipyard & Machinery Works in Nagasaki. Mitsubishi Power handled the design, manufacturing, and installation support, with local subsidiary PT. Mitsubishi Power Indonesia carrying out the on-site installation work through turnkey project execution. Mitsubishi Power achieved operational performance exceeding guaranteed values, adhered to the contract schedule, and completed the project without any safety incidents. This success is the result of the advanced construction technology cultivated by MHI Group, and Mitsubishi Power Indonesia's strong local project execution capabilities.

A ceremony commemorating the project completion and the re-commissioning of Unit 3 was held on October 14 in the Indonesian capital of Jakarta. Alongside this ceremony, Mitsubishi Power and SEG signed a Technical Study and Cooperation Agreement (TSCA) to begin discussions on using the latest maintenance technologies to increase steam turbine output and enhance the plant's reliability and availability. Under this TSCA, Mitsubishi Power Indonesia will support efforts to maximize the asset value of the power plant by introducing the latest technologies from MHI Group to create and deliver unprecedented value. These initiatives are based on the Innovative Total Optimization (ITO) strategy adopted by MHI Group, which aims to provide ongoing value to customers throughout the equipment lifecycle.

Commenting on the project completion, Shigeo Yakushijin, Executive Vice President, Mitsubishi Power, said: "The retrofit of Unit 3 at the Darajat Geothermal Power Plant increased the power output while achieving operational performance exceeding guaranteed values and was completed in a short timeframe without any safety incident. In particular, by adopting innovative construction methods that leverage our expertise as the original designer and manufacturer, and through turnkey project execution, we significantly shortened the construction period, which we believe demonstrates the new value delivered to customers. With its cutting-edge technology and local service structure, MHI Group will continue to be a trusted partner for customers."

MHI Group will continue to pursue efforts for the widespread adoption of high-performance and reliable technologies, contributing to the stable supply of electricity essential for economic development worldwide, as well as energy decarbonization to protect the global environment. Further, through its ITO initiatives, MHI Group will offer customers new value throughout the product lifecycle, and work to create value that transcends conventional boundaries.