Mentarang Induk Hydroelectric Power Plant


Mentarang Induk Hydroelectric Power Plant, commonly abbreviated as MIHEP, is a 1,375 MW hydroelectric power project under development on the Mentarang River in Malinau Regency, North Kalimantan, Indonesia. The project is being developed by PT Kayan Hydropower Nusantara, a joint venture owned by AlamTri Resources, Sarawak Energy, and PT Kayan Patria Pratama.
MIHEP is intended to provide renewable baseload electricity primarily to the KIPI Tanah Kuning, one of Indonesia's largest industrial development zones focusing on green metals, nickel processing, and aluminium smelting.

Background

North Kalimantan has been identified as one of Indonesia's richest hydropower regions, with potential exceeding 9 GW across the Kayan and Mentarang river basins. Development of MIHEP accelerated after the Indonesian government prioritized KIPI as a strategic national project requiring long-term renewable power supply.

Project Description

The project has an installed capacity of 1,375 MW and will use a combination of dam and reservoir-regulated run-of-river hydropower. Major project components include:
  • Main dam and diversion tunnel
  • Powerhouse complex
  • High-voltage 275–500 kV transmission line to KIPI
  • Access roads and auxiliary civil works
Estimated annual electricity generation is 8–9 TWh, depending on hydrological conditions.

Developers and Ownership

As of 2025, ownership of PT Kayan Hydropower Nusantara is as follows:
  • 50% – PT Alamtri Resources Indonesia Tbk
  • 25% – Sarawak Energy Berhad
  • 25% – PT Kayan Patria Pratama
Early development previously involved Sarang Energy Group, though ownership shifted as new investors joined.

Construction

A ceremonial groundbreaking was held on 1 March 2023. Initial works, including access road preparation, began in 2023–2024.
The developer is targeting financial close in 2026, after which full EPC construction is expected to accelerate. Commercial operation is expected around 2029–2030, subject to financing and regulatory processes.

Purpose and Industrial Integration

The project is one of the primary renewable energy sources planned for the KIPI Tanah Kuning industrial zone, which will host:
Supplying these industries with renewable hydropower supports Indonesia's ambition to produce “green metals” for export markets.

Environmental and Social Impact

MIHEP is subject to Indonesia's AMDAL environmental assessment requirements. Mitigation measures include watershed management, biodiversity surveys, sediment control, and engagement with nearby communities in Malinau Regency.