GIS 4

GIS 4 IKN, also referred to as GIS 4 KIPP/Sepaku 150 kV, is a high-voltage Gas Insulated Switchgear (GIS) substation currently under construction to support the electric power distribution system of Ibu Kota Nusantara (IKN), Indonesia's new capital. Specifically, it serves the Kawasan Inti Pusat Pemerintahan (KIPP) or the Central Government Core Area of the capital. This substation is a key infrastructure component under development by PLN Unit Induk Pembangkitan Kalimantan Bagian Timur (UIP KLT).

Purpose and Strategic Role

The primary purpose of GIS 4 is to regulate and distribute electricity efficiently and reliably within the central government zone of IKN. It plays a strategic role in ensuring a stable and modern power infrastructure in alignment with IKN's vision of a smart and sustainable city.

As part of PLN’s Stream 1 infrastructure responsibilities, GIS 4 is one of four interconnected projects supporting IKN’s electrical system. These include:

• The 150 kV GIS 4 IKN/Sepaku substation
• Extension of the Kariangau 150 kV substation (Ext 2 LB direction GIS 4 IKN/Sepaku)
• A 150 kV High-Voltage Overhead Transmission Line (SUTT) from Kariangau to the GIS 4 landing point
• A 150 kV cable/transmission line connecting the GIS 4 KIPP site to the GIS 4 IKN/Sepaku substation

Technology and Advantages

GIS substations like GIS 4 use sulfur hexafluoride (SF₆) gas for insulation, instead of air (as used in conventional Air Insulated Substations or AIS). This gas has excellent dielectric properties, offering superior protection against electrical discharge and environmental conditions. Key advantages include:

• Compact design: GIS equipment occupies significantly less physical space compared to AIS.
• Environmental resilience: Resistant to extreme weather, pollution, and seismic activity.
• High reliability: The sealed environment of GIS systems ensures insulation is unaffected by humidity or contaminants.
• Low maintenance: With fewer exposed components, GIS systems require less routine servicing and have longer service lifespans.

These characteristics make GIS 4 an ideal fit for IKN, which emphasizes a smart, resilient, and future-proof infrastructure.

Development Progress

As of early 2024, GIS 4 construction had reached 50% completion, with foundational and structural works completed. The next development stages include installation of electromechanical equipment, structural reinforcement, foundation casting for transformer switchyards, and site preparation for parking and utility areas. The project is targeting Commercial Operation Date (COD) by May 2024.

Integration with the Kalimantan Grid

GIS 4 is part of the broader Sistem Mahakam, which links electricity systems in East, South, and Central Kalimantan (Sistem Barito), with a total generation capacity of 2,369 MW, well above the current peak demand of 1,545 MW. This surplus supports the growth and stability of energy supply in the new capital and surrounding regions.

GIS 4 IKN/Sepaku represents a cornerstone in the electrification of Nusantara, Indonesia’s future capital. It embodies modern engineering solutions tailored for efficiency, reliability, and sustainability, reinforcing the government's commitment to smart infrastructure development.