Translate page with Google

Story Publication logo February 26, 2024

EVs and the Deep Sea: Should We Mine the Ocean To Make Clean Cars in South Carolina?


This project highlights South Carolina's environmental and economic connections to the ocean.


As EV automakers invest heavily in South Carolina, they're scanning the horizon for new sources of metals to build electric car batteries. One place S.C. carmakers are not yet looking is the deep sea. But that could soon change. 

Cobalt, nickel and manganese lie in abundance on the seafloor. Lumpy, metal-rich rocks the size of tennis balls litter the ocean's depths, both off the coast of South Carolina and in the remote Pacific Ocean. The Post and Courier recently reported on how removing those polymetallic nodules in a 1970s experiment left lasting environmental damage many decades later. 

Despite decades of tinkering and exploring, deep-sea mining has never existed as a commercial enterprise. 

As a nonprofit journalism organization, we depend on your support to fund more than 170 reporting projects every year on critical global and local issues. Donate any amount today to become a Pulitzer Center Champion and receive exclusive benefits!

Cold War-era efforts to exploit the deep faced economic headwinds. In 1994, a United Nations treaty made the international seabed off limits unless countries could agree on a sustainable mining approach. But the growing demand for EV battery materials could push an agreement through as early as this year. 

South Carolina is home to five EV automakers: Mercedes-Benz, BMW, Scout, Volvo and the Volvo subsidiary Polestar. All but Mercedes-Benz have publicly distanced themselves from the nascent business of deep-sea mining. The controversial enterprise, they said, may be unnecessary.

Where SC carmakers stand

In March 2021, S.C.'s two largest carmakers, Volvo and BMW, signed a pledge to not source or use deep-sea metals in their supply chains for the near future. EV brand Polestar later spun off from Volvo and adopted the same anti-mining stance. Instead, the companies are opting for recycling and employing new battery technologies so that future models require fewer amounts of seabed minerals — or none at all. 

Volkswagen has made a similar pledge. The parent company for Scout Motors, an all-electric brand, broke ground on its $2 billion Blythewood plant earlier this month. Executives cited seabed mining's "severe environmental risks" as reasons to support a global ocean mining moratorium. They said their customers don't just want sustainable cars, they want sustainable supply chains. 

Is this a viable path for automakers? Look no further than Richland County.

Last month, Redwood Materials officially began building a key link in South Carolina's circular EV supply chain there. The company broke ground on a $3.5 billion battery recycling plant. Once completed, it will surpass Georgia-based Ascend Elements as the largest battery recycling operation in North America. 

Together, with its Nevada plant and new Palmetto State operation, Redwood said it can recycle enough materials to make 1 million EV batteries sometime next year. By 2030, when today's cobalt-rich EV batteries will be entering this recycling-based circular economy, Redwood said it could produce the raw materials to make 5 million batteries a year.  

SC automaker Mercedes-Benz has not yet come out against deep-sea mining. But the company is similarly investing in recycling operations to close the loop on its own supply chains. Last year, the company broke ground on a battery recycling plant in Germany to source cobalt, nickel and lithium. 

Some carmakers are also investing in new technologies — namely lithium iron phosphate batteries — which don't rely on cobalt and nickel. These so-called LFP batteries are cheaper to make and safer to transport. 

Last year, half of all Teslas coming off the line used LFP technology. Volkswagen announced that it will start offering EV models with LFP batteries sometime this year. Economists estimate that LFP batteries can be found in more than 30 percent of all-electric vehicles being manufactured worldwide today. That number is expected to grow. 

LFP batteries do require small amounts of manganese, a mineral found in the ocean's polymetallic nodules. But, unlike cobalt and nickel, manganese is more abundant on land, including sites in North America. 

“You would not go to the bottom of the sea for manganese,” said Jeanne Everett, director of programs and operations for the environmental group Blue Climate Initiative. Last year, her group authored a white paper highlighting how next-generation EV batteries were "eliminating the need" for mining the deep sea. 

Pro-mining argument

Despite these developments, sourcing critical minerals today is a thorny business.

Most of the world's cobalt currently comes from the Democratic Republic of Congo in Central Africa, where worker safety violations and rampant child labor remain ongoing issues. Indonesia's nickel mining industry is taking a similarly destructive toll on the environment and human life. 

China is another major supplier of critical minerals and fully manufactured EV batteries. 

Kris Van Nijen, CEO of Belgium-based Global Sea Mineral Resources, cites these ethical and geopolitical concerns as the main reason his firm is ready to mine the Pacific Ocean for nodules should this year's treaty negotiations, overseen by the U.N.'s International Seabed Authority, allow for it. 

“Our goal is to come up with responsible solutions for sustainable development worldwide,” said Van Nijen. "If we know we need the metals, then the question is where are we going to get them from in the most responsible way?"

In the U.S., there's also a strong consumer-driven argument for seabed mining, which could make more EVs affordable to more Americans looking to shift away from gas-powered vehicles. 

Geologist Jason Chaytor holds a polymetallic nodule that has been cut in half. These rocks lie on the seafloor of the deep ocean and contain high concentrations of cobalt, nickel and manganese. Image by Laura Bilson/Post and Courier.

A $7,500 tax credit available to U.S. consumers is already driving EV adoption and automakers' appetite for America-friendly metals sourcing. The credit, which was part of the Inflation Reduction Act passed in 2022, was recently restructured to help America and its trade allies outcompete China in the critical minerals trade war.

In order for an EV model to qualify for the tax credit, a certain percentage of its raw materials must be sourced from America or its trade partners. That threshold ramps up as years pass.

The 2024 eligibility rules mean that just 19 EV models qualify for the credit when purchased as new, down from 43 last year.

A Canada-based mining company, The Metals Co., came out in support of the act's clean vehicle credit, saying that seabed mining could fulfill the Biden Administration's goal of decarbonizing the U.S. transportation sector without relying on China. The company said in a 2022 statement that it currently holds leases to mine areas within the Pacific's Clarion-Clipperton Zone that, once fully exploited, could produce enough nodule-extracted minerals to power 280 million car batteries.

That's roughly equivalent to all the cars on the road in America today.  

But even if mining on the high seas is further delayed by ongoing treaty negotiations, mining within countries' own waters is still a possibility. In January, Norway became the first country to allow seabed mining exploration in its own waters. Some think that the U.S. could follow.

What's next? 

In early March, the U.S. Department of Defense will publish a report on deep-sea mining and its potential in domestic waters. The report responds to growing concerns among Republican members of Congress — including South Carolina Republicans Nancy Mace and Ralph Norman — about China’s predicted dominance in the deep-sea metals market.

There are four places in America's waters where nodules occur, including the Blake Plateau just offshore from South Carolina. And while no one is proposing mining there, offshore areas near California, Alaska and Hawaii remain on the table. 

Meanwhile, on March 4, representatives from 168 countries will meet in Jamaica to continue hashing out a "mining code" under which pro-mining countries like Belgium, China and Russia could legally mine the high seas. Notably, the U.S. never ratified the global treaty that manages the international seabed and therefore cannot vote in these negotiations nor apply for licenses to mine. 

Currently, only a handful of companies and countries have the technological capacity to lift nodules from the seafloor at scale. Therefore, land-based mineral sources as well as recycled sources will continue to dominate supply chains in the near future. 

“So, even if deep-sea mining gets underway, it will still — for many decades — be a very tiny contribution to the global metals market,” said Andrew Thaler, a deep-sea biologist and former editor-in-chief of the deep-sea mining sector's only trade journal. 

Meanwhile, scientists continue to work with mining companies to evaluate their environmental impact on the deep sea.

Should seabed mining launch into commercial operation next year, there may be more evidence-based ways to mitigate its damage. Perhaps those mitigation measures will one day be acceptable in the eyes of S.C. carmakers. 

Patrick Schwing is an assistant professor of marine science at Eckerd College in Florida. He is working closely with The Metals Co. to measure mud plumes created by its nodule-collecting robots close to the seafloor. His goal is to find ways to measure, in real time, when those mud plumes grow too large — say, a mile in diameter — which could then trigger a temporary pause in mining operations until the plumes subside.

That research is being funded by the Canada-based firm and is still under development. It was first presented last week at the American Geophysical Union's oceans conference held in New Orleans, La. 

“The seafloor will be two degrees of separation from your car. And, for most of us, it's one degree of separation from our seafood … that's what I remind people," said Schwing, who sees a future for sustainable seabed mining that eco-minded EV buyers could get on board with. 

But, for now, most South Carolina carmakers still disagree. 


yellow halftone illustration of an elephant


Environment and Climate Change

Environment and Climate Change
yellow halftone illustration of two construction workers moving a wheelbarrow of dirt


Extractive Industries

Extractive Industries
a yellow halftone illustration of two trout





logo for the Ocean Reporting Network


Ocean Reporting Network

Ocean Reporting Network

Support our work

Your support ensures great journalism and education on underreported and systemic global issues