Transmission Expansion Planning for the Optimization of Renewable Energy Integration in the Sulawesi Electricity System

Abstract

In order to meet the growth in demand and the renewable energy integration target, the Sulawesi Electricity System (SES) should be expanded. Currently, the SES is divided into two systems, namely South and North Sulawesi. These two systems have different characteristics, such as the system size, reliability and operational cost. North Sulawesi is smaller, weaker and more expensive than the South System. In order to improve the system reliability, generation and transmission expansion planning should be executed simultaneously to meet the economical investment cost and satisfy the reliability standard. For this purpose, the necessity of a backbone system with a higher voltage level than the existing 150 kV system should be considered, including the interconnection option between the two existing systems in Sulawesi. A methodology based on economic and technical criteria was developed to determine the backbone voltage level. Two voltage level options were considered, namely 275 and 500 kV. Several criteria were considered in order to determine the backbone voltage level, including the economic voltage, the line-loading limit, N-1 contingency, short circuiting, transient stability, voltage stability and small signal stability. The backbone voltage candidates should fulfil all of the criteria. The simulation was conducted in base- and high-demand scenarios, considering the fluctuation of future economic growth. The load flow and the dynamic analysis were simulated in a DIgSILENT Power Factory environment. The results showed that the 275 kV backbone, which was built in 2022, would violate three criteria: the economic voltage, N-1 contingency and voltage stability. On the other hand, the 500 kV backbone voltage level fulfills all of the criteria. The result of this research was considered in the electricity planning documents in Sulawesi. From a technical and economical perspective, the 500 kV backbone was chosen for the SES.

Accelerating Renewable Energy Integration in Energy Planning Considering the PV Techno-Economics and Hourly Profile, Case Study: Indonesian Power Sector

“…The focus of research and planning for generation expansion planning by considering renewable energy has been carried out in various countries, both baseload or variable renewable energy. For the example, in the USA (Nguyen and Felder, 2020), Ireland (Fitiwi et al, 2020), France (Seck et al, 2020), China (Chen et al, 2010;Khan et al, 2014;Shengyu et al, 2015), Brazil (Luz et al, 2018), Portugal (Pereira et al, 2017), Egypt (Rady et al, 2018), Pakistan (Shinwari, 2012), Oman (Malik and Kuba, 2015), South Africa (Wright et al, 2019), Bangladesh (Khan, 2019), Malaysia (Shirley and Kammen, 2015) and Indonesia (Budi, 2017;Muthahhari et al, 2019;Muttaqien, 2017;Putranto et al, 2023;Putrisia, 2017;Tumiran et al, 2020Tumiran et al, , 2021 have considered the environmentally friendly resource or renewable energy sources (RES) in their generation expansion planning model.…”

Management Optimization of Electricity System with Sustainability Enhancement

“…Transmission switching is also examined, as a means of harnessing the flexibility of the current transmission infrastructure to reduce the operational costs of the system, in addition to being a control action or as a solution to reduce system losses. Optimal transmission switching (OTS) was, firstly, introduced in [8], as part of the DC optimal power flow. A binary variable shows the on/off status of TLs, within the suggested formulation, while [9] extended the OTS real-time utilization to the AC optimal power flow (ACOPF) context.…”

Muna-Buton System Generation Expansion Planning by Considering the Interconnection System

“…An interconnection between the two systems has previously been carried out [3] by connecting northern Sulawesi and southern Sulawesi. The interconnection was carried out by including two voltage transmission options, 275 kV and 500 kV, and taking into account voltage economy, N-1 contingency, and voltage stability.…”