Island and remote utility modelling for Asia-Pacific

Pacific island states

The Pacific island states — stretching from Palau and the FSM (Federated States of Micronesia) in the north through to Fiji, Samoa, Tonga, and Vanuatu in the south, and the smaller micro-states of Kiribati, Tuvalu, Nauru, and Marshall Islands — collectively share a common challenge: diesel-dependent electricity systems, rising fuel costs driven by long shipping distances, and vulnerability to fuel supply disruption from tropical cyclones and other climate events.

Most Pacific island states have set 100% renewable electricity targets — Tonga by 2035, Samoa by 2025, Vanuatu by 2030 (outer islands), Cook Islands by 2020 (achieved on Rarotonga). World Bank, ADB, NZ MFAT, and Australia DFAT fund the majority of Pacific island energy projects. HOMER Pro is required in the feasibility documentation for most donor-funded Pacific island tenders.

Indonesia — PLN 17,000+ island systems

Indonesia's archipelago — 17,000+ islands, approximately 6,000 inhabited — presents the world's largest island electrification challenge by number of systems. PLN (Perusahaan Listrik Negara), the state utility, operates hundreds of isolated diesel microgrids on outer islands, and the PLN Energi Baru dan Terbarukan (PLN EBT) subsidiary is responsible for renewable integration in these systems. Indonesia's JETP (Just Energy Transition Partnership) and national electrification rate target (100% by 2030) drive active procurement of hybrid renewable systems to replace diesel on outer islands.

HOMER Pro is widely used by engineering consultancies supporting PLN EBT's outer island electrification programme — both for pre-feasibility assessment of diesel-replacement with solar-plus-storage, and for the operational planning of PLN's existing hybrid systems in Maluku, NTT (Nusa Tenggara Timur), Papua, and Kalimantan.

Philippines — SPUG off-grid areas

The Philippines' SPUG (Small Power Utilities Group), a division of NPC (National Power Corporation), supplies electricity to off-grid areas — primarily island communities in the Visayas and Mindanao regions not reached by the Visayas grid or Mindanao grid. SPUG serves approximately 2.5 million people across hundreds of island communities. The Department of Energy's (DOE) Competitive Selection Process for off-grid areas has opened SPUG territories to private IPPs, creating an active project development market for hybrid island systems.

Okinawa Electric Power Company's 39 outer islands — from Miyako-jima and Ishigaki-jima in the south to the Kerama and Kume island groups — represent a developed-country island utility system of exceptional complexity. Unlike Pacific island utilities, OkiElec operates to full Japanese grid reliability standards (SAIDI/SAIFI metrics comparable to mainland urban grids) with a fuel cost profile driven by imported petroleum products. The economics of renewable replacement are compelling and OkiElec has active solar-plus-storage projects across multiple islands.

Japan's wider island electrification transition — across Kyushu, Shikoku, Chugoku, and the island prefectures of Nagasaki, Kagoshima, Ehime, and Okinawa — involves the nine regional utilities, each of which has isolated island systems in their service territory. HOMER Pro models all of these systems against Japan-specific technical standards (JEAC electrical rules, grid code frequency tolerance requirements) and utility-grade reliability targets.