Finding potential locations for hydrogen storage
Hydrogen is the lightest molecule. At regular sea-level pressure, it is a low-density gas. It can be stored in tanks as a gas under high pressure or as a liquid at very cold temperatures.
But for large-scale storage of hydrogen, the cheapest and safest option is underground in salt caverns, depleted gas fields, saline aquifers or engineered hard-rock caverns. Salt cavern storage is the most-ready technology, but depleted gas field storage is likely to be the most promising and widely available in Australia and will require less initial investment.
Our challenge was to find and map potential locations in Australia.
Assessing locations using geological and other data
The potential scale of future demand in Australia ranges from 10,000 tonnes, to stabilise the electricity network, to 2.5 million tonnes for security of the gas network or for potential export. This means we need around 5 million tonnes of storage capacity for a fully developed hydrogen industry.
We assessed the options for underground hydrogen storage in Australia, focusing on suitability for geological storage of hydrogen, capacity and distance to potential hydrogen sources and transport infrastructure.
We used publicly available data (for example, from government geological survey organisations such as Geoscience Australia) to locate sites for the four types of storage around Australia and assessed critical engineering aspects such as storage capacity and suitability for hydrogen containment.
Discovering more than sufficient storage capacity
The good news is we found more than sufficient prospective storage capacity, so we will likely be able meet our needs with a small number of storage facilities.
Future research should focus on finding the best options in terms of economics, storage characteristics, and location in relation to production and infrastructure. We also need to solve some technical challenges and develop robust criteria to help us choose the most suitable locations.