Renewable methane storage in Gippsland for peak and backup power

Abstract

Climate Change mitigation by adopting renewable energies and the depleting gas reservoirs of Australia's Gippsland Basin have introduced insecurity in the Australian energy sector. Urgent measures are needed to avoid future grid failures. This study proposes underground storage of bio-methane (CH4) to meet peak and backup power demands. The depleted gas reservoirs and coal seams of Gippsland are candidates for such a storage. In this study, a facility converting waste biomass into methane and storing it in depleted gas reservoir for meeting peak/backup electricity demand is modelled and simulated. In the model, 200 t/d of biomass is anaerobically digested into methane. Despite this practicable yet relatively small scale when combined with storage, the facility generates 14,000 t (20 million m3) of methane per year, enough to generate over 80,000 MWh of electricity on demand via fuel cells. These results demonstrate the potential for bio-renewables contributing to large scale power demand.