The roles of biomass and CSP in a 100 % renewable electricity supply in Australia

Abstract Because of the variability of wind and solar resources, high shares of wind and solar PV in power supply systems can lead to supply gaps during occasional low-resource periods. Due to their ability to meet demand in a short term, dispatchable renewable energy (RE) resources – biomass, concentrating solar power (CSP) and hydropower – can assist in meeting such supply gaps. In this study, we investigate the spatial and temporal configurations of least-cost 100% renewable power supply in Australia, at various levels of biomass resource use and CSP penetration. To this end, we carry out a high-resolution Geographic Information System (GIS)-based hourly electricity supply-demand matching simulation. We find that, based on the current existing biomass capacity (1.7 GW) installed in Australia, a 100% national RE supply is possible with around 146–148 GW system installed capacity at a levelized cost of electricity (LCoE) of 9–10 US' kWh−1 (95% level of confidence). Under a 5–15 times expansion of biomass, the system capacity would be reduced to around 70–110 GW at an LCoE of 6–8 US' kWh−1. Depending on limitations to the generation from biomass posed by competing land uses, CSP could play an important role in reducing the system capacity to nearly 120 GW.