A "natural hydrogen" start-up chaired by former Liberal politician Alexander Downer has listed on the Australian share market.
Gold Hydrogen's offering at 50 cents a share was fully subscribed, which meant the company launched on Friday with a market value of $70 million.
Shares in Gold Hydrogen were up three cents or six per cent at 53 cents in early afternoon trade.
The company says it intends to help the transition to a decarbonised economy by drilling for underground hydrogen across nearly 8000 square kilometres of South Australia.
Once a geological curiosity, confirming the existence and potential commercialisation of this type of hydrogen - a gas found in layers of rock - would be an Australian first.
Although Australia's focus is on the development of green hydrogen using renewable processes, proponents of natural hydrogen say it's a potential low-carbon alternative for manufacturing, transport, heating and power generation.
Gold Hydrogen will explore sites in Yorke Peninsula and Kangaroo Island in South Australia.
"To know we have the support of so many people in the hunt for low carbon energy sources, and that the search starts in my own state, is incredibly humbling," Mr Downer said.
Gold Hydrogen is focusing initial exploration in the Stansbury Basin, Kanmantoo Trough and Kanmantoo Platforms of the state.
An airborne survey is scheduled to commence in March, followed by exploration drilling of three wells in the September quarter of 2023.
The former foreign minister and diplomat said it was very exciting for South Australia and Australia.
Mr Downer believes there's around 1.3 billion kilograms of natural hydrogen to be found.
Gold Hydrogen is also the preferred applicant for four gas storage exploration licence applications within the renewable energy zone of the Yorke Peninsula region.