Chevron tallies new investment for Gorgon carbon trap

The vast Gorgon project on Barrow Island about 60 kilometres off the northwest coast of Western Australia is the largest single-resource project in Australia's history.

The three-train, 15.6 million tonnes per year liquefied natural gas facility fuels Asian economies, while the domestic gas plant makes it the state's biggest supplier.

It was required by regulators to include a carbon capture and storage system that critics have slammed as a failure because the injection rate of 1.6 million tonnes per year are one third of the target.

The system needs to run alongside the LNG and gas plant for the next 40 years, and reduce emissions as well as store them.

"We're not going to hide from the fact that it's not achieving what we wanted it to achieve," Chevron Australia general manager of energy transition David Fallon told AAP.

"It's a bit like a Tupperware container," he said, with water needing to move from one to another.

Trace oil and gas has been clogging it up, meaning the operations have had to reduce pressure in the "container", which slashes carbon injection rates.

Mr Fallon said the company was committed to getting it back to four million tonnes a year and was sharing information within the industry in Australia to make sure their challenges weren't repeated elsewhere.

A final investment decision on improving Gorgon's carbon capture water handling system - vital for getting it back on target - will be made in the second half of the year.

He declined to give a ballpark figure for the cost, which he said would be covered by the venture partners rather than taxpayers.

Concerns were raised almost two decades ago about plans to pump the project's exhaust underground to cut emissions from tapping the field estimated at 40 trillion cubic feet of gas.

Then environment minister Mark McGowan announced in 2006 the project would go ahead, despite biodiversity concerns for an area rich in turtles, wallabies, bandicoots and birds.

The technology remains much-maligned despite China and the United States accelerating uptake to tackle pollution from power plants and heavy industries.

Woodside boss Meg O'Neill told the Australian Petroleum Production and Exploration Association conference the technology had been judged too soon.

"It works," she said.

Potentially, the captured carbon could be re-used onsite, injected deep underground or compressed and transported by pipeline, ship, rail or truck.

"We need it to decarbonise heavy industries such as steel, cement and chemicals in order for these sectors to meet their considerable emission targets," APPEA chief executive Samantha McCulloch said.

Developers have announced hundreds of capture facilities to be operating by 2030, but only a handful of commercial capture projects under development have made a final investment decision.

Climate Energy Finance director Tim Buckley said the run rates at Gorgon undermine the industry's push for carbon capture and storage.

But Mr Fallon said the Moomba project Santos was developing with Beach Energy in South Australia wouldn't experience the same challenges.

Injecting carbon into depleted oil and gas reservoirs as Santos intended was a very different proposition, he said.

So-called saline aquifers, similar to Gorgon, could also perform differently depending on the geology.

"We need to be careful about saying all of CCS won't work because of the challenges we've had," Mr Fallon said.

Australian Associated Press