New study finds deep sea rocks for EV batteries reduces climate impact

By CARSIFU | 25 September 2020

VANCOUVER: As the world rushes to replace fossil fuels with renewable sources of energy, new research shows that polymetallic rocks found on the deep-ocean floor can supply hundreds of millions of tons of important battery metals to store energy and power electric vehicles (EVs) with far less impact on the climate than mining the same metals from the land.

The peer-reviewed study published in the Journal of Cleaner Production, is a comparative life cycle assessment of EV battery metal sources, quantifying the direct and indirect emissions and disruptions to carbon sequestration services realized in the mining, processing and refining of battery metals.

The carbon intensity of producing metals like nickel has led to growing interest in low-carbon metal sources and a recent plea by Tesla’s Elon Musk promising “a giant contract” for nickel mined “efficiently and in an environmentally sensitive way.”

As EV manufacturers like Tesla and Polestar spearhead a movement for transparency throughout the automotive industry and reveal the lifetime carbon footprints of their cars, the new study goes beyond just considering carbon emissions from human operations to look at the disruption of ecosystem carbon sequestration services caused by changes in land and seabed use to produce battery metals.

Entitled ‘Life Cycle Climate Change Impacts of Producing Battery Metals from Land Ores versus Deep-Sea Polymetallic Nodules’, the paper starts with a demand scenario of producing four metals (nickel, cobalt, manganese, copper) to supply one billion 75KWh EV batteries with a cathode chemistry of NMC 811 (80% nickel, 10% manganese, 10% cobalt).

It then compares the climate change impacts of supplying these four metals from two sources: conventional ores found on land and polymetallic rocks with high concentrations of four metals in a single ore, found unattached on the seafloor at 4-6km depth.


“We wanted to assess how metal production using either land ores or polymetallic nodules can contribute to climate change. Looking from mining to processing and refining, we quantified three indicators for each ore type: direct and indirect carbon-dioxide-equivalent emissions, disturbance of existing sequestered-carbon stores, and disruption of future carbon-sequestration services. These three indicators directly impact the remaining global carbon budget to stay below 1.5C warming,” said the study’s lead author Daina Paulikas of the University of Delaware’s Center for Minerals, Materials and Society.

The researchers’ focus on climate change impacts builds on a larger study, Where Should Metals For the Green Transition Come From?, that compares a range of social and environmental impacts and was commissioned by DeepGreen Metals, a company seeking to collect polymetallic rocks to supply electric vehicles under a blockchain-enabled system to rent and reuse battery materials.

“This peer-reviewed study shows the intrinsic benefits of seafloor rocks when it comes to climate change impacts. The resource itself gives us a significant head start on land miners, but being low carbon is not enough. We are working on taking carbon out of the atmosphere, not adding it,” said Gerard Barron, Chairman and CEO of DeepGreen Metals.

“We’ll use hydropower onshore; we are exploring electrofuels to power offshore operations and using electric equipment and carbon-negative reductants in metallurgical processing. Put it all together, and we have a shot at bringing carbon-negative metals to the market.” -Pix by REUTERS