The Contribution of Flexible Sector Coupling to Fully Renewable Electricity Generation in Australia

With the sharp decline in costs, wind and especially solar power generation has been strongly increasing in Australia over the past years. Given its abundant space and high-quality potential, Australia has great opportunities to cover its complete energy demand from renewable sources. This case study evaluates the role of flexible sector coupling in a climate-neutral energy supply system for Australia, using the established high resolution energy system model REMix. More specifically, it addresses the question how it can contribute to the balancing of renewable power supply, complementing storage and transport of energy. Energy sector coupling refers to direct or indirect electrification of the transport and heating sector through electric heating, electric driving and the usage of synthetic fuels. All these options are included in the model. The model results show that with the expected cost developments, utility-scale photovoltaics (PV) would be the cheapest energy source in Australia. This would be supplemented by onshore wind power generation and roof-mounted PV. A significant contribution to balancing is made by the power grid and pumped hydro as well as battery storage. Of greater importance, however, is the flexibility provided by sector coupling. This applies in particular to the flexible production of hydrogen, which is stored in large storage facilities and transported via long-distance pipelines, but also to load management of electric vehicles, cooling and heating.