Cost-optimal configuration of a renewable-based Australian power system

Abstract

Proposed emission reduction targets and the scarcity of fossil fuel resources make a transition of the energy system towards an emission-free electricity supply necessary. Australia represents an interesting case for energy system transformation modelling. While it currently has a power system dominated by fossil fuels, and specifically with a heavy coal component, there is a vast potential for expansion and use of renewable energy, in particular solar and wind energy. However, integrating high shares of such variable renewable energy sources challenges the power system due to their temporal fluctuations and geographical dispersion. This paper applies a state-resolved energy system model for Australia, based on linear optimization. We investigate the cost-optimal configuration of a renewable-based Australian power system and its transformation pathway inline with the ambitious proposed climate targets. We particularly analyze the implications of storage and power transmission grid extensions in a prospective, highly renewable Australian power system. Spatial smoothening effects of a powerful transmission grid reduces the required backup and renewable capacities and thus contributes to further reduction of the total system costs