Sceptics question BHP pursuit of 'risky' carbon capture

Climate activists Lock the Gate Alliance protested BHP's "greenwashing" and shareholders questioned how the company could meet its goal of net-zero scope-three emissions, those produced indirectly up or down the value chain, while mining coal into the next century.

Chair Ken MacKenzie argues carbon capture and storage could help achieve BHP's emissions targets. (James Ross/AAP PHOTOS)

One shareholder asked why BHP was over-investing in a risky, unproven technology like CCUS when other commercial-scale technologies were more effective at reducing emissions.

Mr MacKenzie said the company was exploring other ways to reduce emissions from steel production, including Direct Reduced Iron (DRI) and electric arc furnaces.

"And yes, unapologetically, we're looking at CCUS because it's a potential solution to create near-zero blast furnace base, which is the dominant technology out there today," he said.

Other methods were insufficient to meet global demand because they relied on high-grade iron ore and scrap metal, of which there is not enough in the world, Mr MacKenzie said.

He pointed to existing CCUS steelmaking operations as proof the technology was commercially viable, including one up and running in the United Arab Emirates and projects planned in the US, China and Belgium.

But Simon Nicholas, lead steel analyst at the Institute for Energy Economics and Financial Analysis, said the Emirati project was for DRI-based steel and there were no commercial-scale CCUS plants for coal-based steelmaking in the world.

"It is totally unproven and it's really going nowhere fast," he told AAP.

"It's becoming more and more apparent that CCUS is not going to play a major role in steel decarbonisation."

One expert says it is in BHP's interests to convince people carbon capture will solve the problem. (Julian Smith/AAP PHOTOS)

Green steel technology was much more promising, Mr Nicholas argued. 

Miners were increasingly targeting high-grade iron ore, used in DRI furnaces with green hydrogen, and more scrap steel was likely to become available, particularly from China, for use in electric furnaces.

Mr Nicholas questioned why BHP was backing the technology when competitors like Fortescue, Vale and Rio Tinto were not.

"BHP is the only one that is a metallurgical coal miner," he said.

"It's in their interests to convince people that CCUS is going to solve the problem and allow us to continue to using metallurgical coal and the low-grade iron ore that BHP is continuing to mine.

"I don't see how they're going to meet their scope-three emissions goal.

"You just can't do that if you're still mining coal and sending your low-grade iron ore to be processed in blast furnaces, because CCUS will never reduce emissions by enough."

The climate plan still passed easily, with more than 92 per cent of shareholders voting in its favour.