Network Extensions to Remote Areas

Overview

As operator of the Australian National Electricity Market (NEM), AEMO manage the connections to the shared grid. The geography of Australia gives rise to situations where new generation can be very remote from the grid. Innate properties of long transmissions lines connecting remote generation introduces electrical conditions that must be carefully considered during the planning and design phases to ensure safety and proper operation of these connections and installations hence maintaining grid integrity, reliability, and stability.

AEMO wished to publish a guideline on considerations that should be taken into account when planning such transmission schemes to connect remote generation to the existing shared grid in Australia.

PSC, being a specialist consultant in the field of network analysis and system studies were contracted by AEMO to prepare a guide on technical planning considerations for remote network extensions, including how these considerations relate to cost; and to provide a hypothetical case study of the application of the planning considerations for connecting remote geothermal generation at Innamincka in South Australia to the shared grid.

PSC subsequently developed the guidelines and proceeded to apply these to the Innamincka case study. This required models to be developed for various network extension and interconnection scenarios including staged Innamincka generation of 500MW, 2000MW, and 5000MW. Six transmission development options were studied connecting Innamincka to Adelaide, Melbourne, Sydney, and Western Downs in Queensland using either AC transmission at 500kV and 765kV, or HVDC transmission at +/-500kV and +/-800kV.

The development options were selected to explore possibilities for the application of AC and HVDC technologies, and to show how each technology could be staged to match growth in generation. Each development option was partially optimized so as to provide a reasonable indicative comparison of likely capital costs.

The design for the different development options took into account a number of the planning considerations discussed in the technical planning guide, including selecting a transmission route, AC or HVDC transmission, transmission voltage and losses, security, staging, and choice of connection points on the shared grid.

Meeting Objectives and Requirements

This project was delivered to a fixed price within the clients budget and within an extremely tight timeframe in order to meet AEMO’s commitments to the NEM.

The project is frequently referenced by engineering studies in the NEM as a technical and financial guide for long distance network extensions. This project is an example of how a major system operator (AEMO) has used PSC capability and experience to provide public guidance to market participants in the area of system studies.

PSC Services

PSC are a specialist consultant providing network analysis skills and resources and also with a strong capability in electricity market operations. Our industry experience places us at the forefront of capability and understanding in this area. Our clients benefit from our thorough knowledge and understanding of electricity networks which is further supported by real world experience across many clients, projects and regions.