Incalculable riches, delicate ecosystem, and the green energy future.

Deep-sea mining has captured the world's attention as a uniquely promising source of the metals needed for lithium-ion batteries powering the green energy future and a bitterly controversial topic of debate.

Undersea deposits contain quantities of nickel, cobalt, copper, and manganese sufficient to replace every U.S. car on the road today with an electric vehicle. They also host some of the most diverse, little-known, and least-understood ecosystems.

This young industry is up against the global warming time crunch, expensive engineering challenges, and projected mineral scarcities that have much more to do with how green a resource is than how much is available.

Energy transition industries in every nation are working to be able to access the material they need quickly and cheaply enough, all while laboring under dire cautions not to make the same mistakes that got us here.

Soon, it will be time to decide what to do with the greatest untapped resource on Earth, nestled deep in the so-called lungs of the planet.

Batteries in a rock

Much of the conventional terrestrial reserves of nickel, cobalt, and manganese are found in Russia, Indonesia, the Congo and South Africa, countries with insufficient protections for biodiversity, worker rights and population welfare.

The oceans of the world have three types of ore deposits – seafloor massive sulfides, polymetallic nodules, and cobalt crusts – with nodules dominating interest over the last couple of years.

• Cobalt-rich ferromanganese crusts occur between 400 and 5,000 meters in areas of significant volcanic activity. The crusts grow on hard-rock substrates of volcanic origin through precipitation of dissolved metals. Similar in general composition to polymetallic nodules, they are attracting investment in exploration for cobalt, platinum, rare earth elements, nickel, and manganese.

• Seafloor massive sulfides are hydrothermal mineral deposits (also known as black smokers) that form on and below the ocean floor. They are made up of sulfur compounds and base metals like copper, zinc, lead, iron, silver, and gold. More than 350 sites of high-temperature hydrothermal vents and about two hundred sites of significant massive sulfide accumulation have been identified since the 1970s.

• Polymetallic nodules contain layers of iron and manganese around a small core of ocean detritus, layered with a veritable wish list of critical minerals tailor-made for battery chemistry needs, including nickel, copper and cobalt, rare earth elements, and even lithium. The nodules are formed by the slow accretion of minerals from seawater, less than four millimeters per million years.

The Metals Company

Polymetallic nodules have high concentrations of battery metals like cobalt, manganese, and nickel.

The abyssal plains where nodules develop are the relatively flat regions that cover more than 50% of the seafloor between 3,000 and 6,000 meters (1.86 to 3.72 miles) down, where polymetallic nodules reside under dark, corrosively salty, equipment-crushing pressures.

So far, their desirability and economic value outweigh the expense of their retrieval. Unlike ores on land, which rarely have metal yields above 20% and are often less than 2%, seabed nodules are 99% usable minerals and aren't toxic to excavate.

Viable deposits of nodules have been identified in the north-central Pacific Ocean, the Peruvian basin in the southeast Pacific, and the Indian Ocean – the most promising being the Clarion Clipperton Zone (CCZ), an abyssal plain in the equatorial Pacific Ocean between Central America and Hawaii, roughly half the size of Canada and potentially containing more nickel, manganese and cobalt than all the combined deposits on land to date.

The lawless sea

Environmental concerns and vague legislation surrounding deep-sea mining have created a rift that has divided governments, electronics giants, vehicle manufacturers, banks, and scientists across unexpected lines.

So far, 31 contracts to explore and reserve specific zones of international waters for potential commercial mining have been granted by the International Seabed Authority (ISA), an autonomous UN-affiliated regulatory body with a history of ponderous deliberations.

After sufficient exploration, resource definition, and environmental baseline studies, commercial mining itself will require additional permitting. With mining contractors chomping at the bit, the ISA has slowly been developing its body of regulations in that regard, coined the Mining Code.

According to an article for the World Resources Institute, "after failing to reach an agreement in July 2023, the ISA now has until 2025 to finalize regulations that will dictate whether and how countries could pursue deep-sea mining in international waters."

Meanwhile, 19 of the ISA contracts issued so far permit the exploration of polymetallic nodules, seventeen of which are in the CCZ. Another seven contracts are for exploring polymetallic sulfides in the South West Indian, Central Indian, and Mid-Atlantic Ridges, and five are for cobalt-rich ferromanganese crusts, all in the Western Pacific Ocean. Each contractor is required to submit a contingency plan to respond effectively to incidents arising from its activities in the exploration area.

Hurry up and wait

A surprising assortment of financial institutions, big industry names, and countries have joined in petitioning for a moratorium on deep-sea mining or distanced themselves by excluding subsea metals from procurement and investment policies.

Notable supporters of a pause include:

• Automotive manufacturers Ford, BMW, Volkswagen, and Volvo

• European Parliament, Germany, Chile, Spain, and several Pacific Island nations

• Tech giants Samsung SDI, Philips, Microsoft, and Google.

Tesla and General Motors have stayed out of it, remaining uncommitted. China, Japan, Russia, India, Mexico, Nauru, Norway, and the United Kingdom are some of the countries that support fast-tracking licenses for mining and are eager to get on with the long and complicated process of commercial extraction.

Commission for Environmental Cooperation

There are two types of DSM jurisdictions: A nation's Exclusive Economic Zone (EEZ) and the high seas, also known as Areas Beyond National Jurisdiction (ABNJ).

The ISA regulates the mining of ABNJ, which is roughly 58% of the planet's oceans. The 150 nations with EEZs are responsible for regulating the remaining 42% of the ocean, with over a dozen of them working to finalize their own DSM standards.

While international policy set by the ISA can set the tone for mining regulations, each of the 150 EEZ jurisdictions will establish its own policies.

India, Norway, and Japan have already begun exploring their EEZs.

• India's Ministry of Earth Sciences launched the five-year Deep Ocean Mission in 2021, an initiative to undertake deep ocean exploration focused on India's EEZs and continental shelf. The Matsya 6000 project vehicle is designed to get three personnel down 6,000 meters to the seabed to retrieve a sampling of polymetallic nodules.

• Norway's EEZ boasts massive sulfide deposits near inactive hydrothermal vents, not nodules. If all goes to plan, contractor permits for exploration should be obtainable by 2025, requiring data collection for up to eight years before starting to mine in 2032, assuming legislation to approve mining is approved.

• Analysis of Japan's nodule samples from this year indicates a rich resource, with the amount of cobalt alone estimated at about 610,000 tons, equivalent to 75 years of Japan's annual consumption, and nickel at some 740,000 tons, worth about 11 years. Researchers at the University of Tokyo and the Nippon Foundation announced further plans to launch a large-scale test project to harvest the nodules as early as next year, followed by a joint venture in 2026 with multiple Japanese companies for processing.

Testing, testing

Technically, no one is mining yet – while more research is done to better understand what's at stake, data collection via exploration is the inevitable next step. In various countries' EEZs, commercial mining will likely be attempted in this decade, and the data will flow.

The seafloor hosts millions of square kilometers of metal ores. The nodules alone (with concentrations depending on location) demonstrably hold at least 38 different elements on the periodic table – fields of these knobby little potato-sized rocks containing everything needed for a smooth energy transition.

ROV KIEL 6000 for GEOMAR (creative commons)

While some argue that polymetallic nodule harvesting has less of an environmental impact than terrestrial mining, others contend that not enough is known about its impacts and a moratorium is better than finding out by way of irreversible damage.

Their composition is so fortuitous Gerard Barron, CEO of The Metals Company (TMC), nicknamed them "batteries in a rock," and it stuck.

Through its subsidiaries, TMC holds exploration and commercial rights to three polymetallic nodule areas in the CCZ from the ISA. During pilot-scale nodule processing this year, TMC and SGS Canada produced the world's first nickel sulfate from nodules, verifying the resource's promise.

"The data collected will inform further engineering decisions to move this towards commercial scale, and TMC continues to expect that initial production will begin with a capital-light approach by leveraging the existing processing facilities of strategic partners, such as PAMCO. With the commencement of this new industry now being seen as imminent by countries and companies alike, this represents not just a major achievement for TMC but for the entire deep-seafloor minerals industry," said TMC Head of Onshore Development Jeffrey Donald.

Though they've been studied since at least the 1870s, the nodules' appeal for the green energy transition has inspired a new generation of investors and miners.

Author John L. Mero first raised the idea of marine mining in a 1960 article in Scientific American and later a book, The Mineral Resources of the Sea, which roused interest in marine mining. At the time, retrieval technology was unequal to the task.

Mero emphasized that marine mining could replace the great despoiler: on-land mineral extraction.

Barron is an outspoken advocate of this idea today, who has strongly influenced the forward momentum of investment and public awareness and taken swift and thorough advantage of exploration permissions.

In 2022, TMC's subsidiary Nauru Ocean Resources Inc. (NORI) and offshore partner Allseas successfully concluded the first integrated system test in the CCZ, driving a pilot collector vehicle across over 50 miles of the seafloor and bringing over 3,000 metric tons up a 2.7-mile riser system to the surface production vessel, Hidden Gem.

Two sides of the same coin

The seas outside national jurisdictions have been the subject of a tug-of-war between commercial interests and environmentalists since the 1970s. While the worldwide debate for and against harvesting critical minerals from international waters rages on, exploration is already underway.

In the headlines are two camps, staunchly polarized opponents that remain unmovable in their ideals.

The first advocates for marine mining with tried-and-true methods of extraction with assurances that it is the lesser of two evils – it's better than mining on land. Proponents assert that extracting minerals from the deep sea would have fewer impacts on nature and human lives than land-based mining does.

The second team insists too little is known about the ocean and the role it plays in the health of the planet, the risk is too great, and what we don't know might come back to bite us – an indefinite moratorium is best.

On balance, there is a third, overlooked faction of practical visionaries and engineers that will not be swayed by the oversimplification of a complex issue. Both positions have good points, and innovators should diligently work to meet in the middle with solutions.

While TMC's online progress reports and charismatic CEO dominate the headlines, a lesser-known sea mining enterprise sailed onto TIME's inaugural list of 250 companies, reducing environmental impact this year.

That company, based out of California, is Impossible Metals – and its co-founders Renee Grogan and Oliver Gunasekara, tackling the problem with a common-sense approach that reflects the views of the deep-sea mining centrists – polymetallic nodules can be a saving grace in the planet's time of need, and the oceans deserve an extraction technology that creates the least disturbance possible.

"We are accelerating clean energy by harvesting critical battery metals from the seabed, while protecting the environment. We are building underwater robotic vehicles for harvesting, and have invented a new form of mineral processing that uses bacteria metal respiration," reads the company profile.

Impossible Metals

Its innovative approach includes autonomous underwater vehicles (AUVs) equipped with a robotic collection system that hovers above the seafloor, using "pick and place" manipulator technology to harvest nodules individually, minimizing disturbance of the sediment and seafloor ecosystems. Image-sensing technology is designed to identify flora and fauna present and leave those nodules untouch