My Journey's Notes: November 2010

Introduction of Sumatra Transmission System

I. PREFACE

Perusahaan Listrik Negara (PLN) is a state-owned electricity company running the business of supplying the electrical energy at a wider area of Indonesian archipelago. Its operational activities include the generation, transmission and distribution of electricity.

Transmission and Load Dispatch Centre of Sumatra, known as P3B Sumatra build in 2005, is one of PLN’s unit that is responsible for the transmission of electricity in Sumatra. Sumatra’s transmission system consists of two major interconnected subsystems, Northern Sumatra and Middle Southern Sumatra. Northern Sumatra covers two provinces: Nangroe Aceh Darussalam (NAD) and North Sumatera, whereas Middle Southern covers six provinces: Riau, West Sumatra, Jambi, South Sumatra, Bengkulu and Lampung. Other provinces such as Batam and Bangka Belitung are isolated system so that they are out of P3B Sumatra’s responsibility.

Based on quarterly Management Report in 2005 - 2009 Northern Subsystem’s peak demand was 1.361,4 MW and its average nett capacity supply in peak load was 1.141,6 MW. Whereas until September 2010, its peak demand was 1.442,8 MW and its average nett capacity supply was 1.335,4 MW. In Middle Southern Subsystem, 2005 – 2009, its peak demand was 1.886,6 MW and its average nett capacity supply in peak load was 1.595,3 MW. Until September 2010, its peak demand was 1.973,8 MW and its average nett capacity supply was 1.707,1 MW. According to these, either Northern Subsystem or Middle Southern Subsystem has been in power deficit for the past five year. Northern subsystem’s deficit can be expected to average 105,2 MW and Middle Southern subsystem’s deficit is expected to average 110,1 MW.

II. SUMATRA TRANSMISSION SYSTEM

Transmission and Load Dispatch Centre of Sumatra (P3B Sumatra) has 11 units, they consist of 8 Transmission Service Units (UPT) and 3 Load Dispatch Units (UPB). The 8 UPTs are: UPT Aceh, UPT Medan, UPT Pematang Siantar, UPT Pekanbaru, UPT Padang, UPT Palembang, UPT Bengkulu and UPT Tanjung Karang. And the 3 UPBs are: UPB Sumbagut, UPB Sumbagteng and UPB Sumbagsel.

Transmission Service Unit is a unit that is responsible for the maintenance of power transmission installation in its regional area which its functions are: 1. for protection and metering maintenance; 2. For transmission installation maintenance; 3. For SCADA (Supervisory Control and Data Acquisition) and Telecommunication maintenance; 4. For operational supervision; 5. For logistic, environment management and electricity safety ; 6. For management and development of human resources comprehensively; and 7. For management of Administration and Finance to support Operation and Maintenance installation tasks.

Whereas the Load Dispatch Unit is responsible for the operation of power system in its regional area which its functions are: 1. to make a dispatch planning referring to energy management principles; and 2. to plan, operate and maintain the operational system facility referring to Sumatra’s Grid Code.

To know the whole Sumatra Transmission System in each province, look at these picture below:

1. Nangroe Aceh Darussalam (NAD)