Indonesia’s Electricity Systems – Overview of the Major Grids

As Indonesia is an archipelago consisting of thousands of islands, there are hundreds of standalone electricity networks that are operated by state-owned electricity utility PLN (or its subsidiaries).

Indonesia’s electricity supply situation in 2015 (Source: Deloitte)

The largest of these networks is the Jawa-Madura-Bali system that spans across the islands of Jawa, Madura and Bali and has over 35GW of installed generation capacity. The Sumatera interconnected system is next with over 8.5GW of installed capacity, although it is normally operated as two separate systems. The South Sulawesi and South, Central and East Kalimantan systems are also relatively large (>1GW), after which the grid capacities drop off rapidly.

The following list shows the largest contiguous systems by peak load (based on RUPTL 2017-2026):

Grid / System Location Peak Load (MW)
Jawa-Madura-Bali Java, Madura and Bali islands 26,646
Sumatera Bagian Selatan & Tengah South and central Sumatera 3,582
Sumatera Bagian Utara North Sumatera and Aceh 2,388
Sulawesi Bagian Selatan South Sulawesi and Palu 1,452
Kalimantan Selatan, Tengah & Timur (*) South, central and east Kalimantan 981
Batam Batam, Riau Islands 392
Sulawesi Bagian Utara North Sulawesi and Gorontalo 364
Kalimantan Barat West Kalimantan 306
Lombok Lombok, Nusa Tenggara Barat 248
Bangka Bangka, Bangka Belitung 144
Timor Timor, Nusa Tenggara Timur 108
Kendari Southeast Sulawesi 83
Jayapura Papua 83
Ambon Maluku 67

(*) Note that the interconnection between the Kalimantan Selatan & Tengah (Kalselteng) and the Kalimantan Timur (Kaltim) systems is currently under construction and expected to be finished by the end of 2017.

In the next series of articles, we will profile each of these major grids in more detail, describing their unique characteristics and energy mixes.