Rio Tinto to trial biofuel crop farming for renewable diesel production

Rio Tinto has announced it will develop pongamia seed farms in Australia as part of a new biofuels pilot. The project will explore the potential of pongamia seed oil as a feedstock for renewable diesel, a cleaner alternative to traditional fossil fuels.

The pilot aims to determine if pongamia seed oil can contribute to Rio Tinto’s renewable diesel needs while potentially contributing to the growth of a new biofuel sector in Australia. Rio Tinto is in the final stages of acquiring approximately 3000 hectares of cleared land near Townsville in North Queensland to establish farms to study growth conditions and measure seed oil yields.

Pongamia (millettia pinnata) is a legume tree native to Australia. Fast-growing and resilient, it produces oil-rich seeds that can be processed into renewable diesel, which offers a significant reduction in life cycle carbon emissions compared to fossil fuel diesel. Pongamia seed can be harvested annually, leaving the trees and soil intact to store carbon dioxide.

Rio Tinto has partnered with woodfibre processing company Midway Limited to oversee the planting and management of the pongamia seed farms. Midway Limited will engage with nurseries, agricultural experts and research organisations throughout the pilot, and prioritise opportunities for Traditional Owners and local communities.

Rio Tinto says that as part of its ongoing efforts to achieve net-zero scope 1 and 2 carbon emissions by 2050, it is actively exploring the potential of biofuels in the low-carbon energy mix. The company sees biofuels as an avenue to reduce reliance on fossil diesel while fleet electrification technologies mature. Rio Tinto is also investigating how biofuels could be used in scenarios where electrification may face practical limitations.

“Diesel accounts for around 10% of our emissions footprint in Australia,” said Rio Tinto Chief Decarbonisation Officer Jonathon McCarthy. “While we continue to pursue electrification as the long-term solution for displacing the majority of our diesel use, the pongamia seed pilot is an important parallel pathway that could reduce our reliance on diesel in the mid-term. It also presents a compelling option for other applications that are challenging to electrify, including blasting and non-haul equipment.

“Australia does not yet have a biofuel feedstock industry sufficient to meet domestic demand. A sustainable biofuels industry here could enhance the region’s fuel security, create local economic opportunities and contribute to emissions reductions targets,” he added. “We are excited about the potential of the pongamia seed pilot and look forward to partnering with Midway Limited and North Queensland communities.”

Image: Rio Tinto Chief Decarbonisation Officer Jonathon McCarthy flanked by pongamia trees.