The transition to a sustainable energy system based on renewable sources is making the demand for rechargeable batteries explode. And therefore also the need for raw materials such as lithium, nickel and cobalt. Deep-sea mining of “metal nodules” may offer a solution in this regard. It would also be a welcome alternative to the often problematic extraction of critical battery raw materials on land.

The figures leave little to the imagination. According to the International Energy Agency (IEA), the demand for lithium, graphite, cobalt and nickel will rise exponentially in the coming years, by at least a factor of 20 for nickel and for lithium even by a factor of 42. The reason for this is the transition to an energy system based on renewable energy. This system is highly electrified and relies on a large storage capacity. In short, the transition is making the need for rechargeable batteries rise exponentially. And these raw materials are crucial for the production of electric vehicle batteries, for example. The message from the Executive Director of the IEA, Fatih Birol, when he published the above figures last year was therefore clear: ‘We are heading for a mismatch between the world’s climate ambitions and the availability of critical raw materials to meet them.’


While everyone agrees that we need to move towards a circular economy as fast as possible, our present society does not have enough metals to recycle. According to the same IEA report, recycling will be able to meet only 10% of the need for primary metals by 2040.

Uncertain supply
One problem with the current supply of critical battery raw materials, which is nowhere near adequate to meet the ever-growing demand, is that it is uncertain. Not only the extraction, but also the processing of the raw materials are highly concentrated geographically. For example, 70% of the cobalt used today comes from Congo, and 60% of it is processed in China. This is not what anyone would call a healthy security of supply, which would benefit from far greater diversity on the supply side.

There is also the problematic impact of mining and processing on the local environment. Currently accessible, rich ore reserves are depleted and mining companies need to look for new sources, the environmental and climate footprint of mining is growing. New mines are often located in areas of rich but fragile biodiversity, such as the nickel mines in Indonesia. These activities also create a residue stream, which is often toxic and must be disposed of. Finally, there is also the social impact of mining. The inhumane methods used to mine cobalt in Congo don’t exactly give the resulting batteries a positive image.

Metal nodules for the taking
The world therefore urgently needs a sustainable, socially responsible source of critical battery raw materials. The good news is that this exists and is even well known. Billions of so-called metal nodules are scattered on the ocean floor around the world, waiting to be harvested. The fist-sized, spherical mineral deposits are formed over millions of years as various minerals in the sediment and the water column are deposited around a nucleus, often a tooth or a piece of bone. The nodules contain a range of metals, such as manganese, nickel, copper and cobalt. To date, the richest known ‘deep-sea mine’ lies in the Pacific Ocean at a depth of five kilometres below the surface. This so-called Clarion-Clipperton Zone (CCZ) contains twice as much nickel and three times as much cobalt as all known ore reserves on land. Moreover, because four metals occur together in the nodules, the CCZ is in fact a combination of several land mines, as you won’t find these four metals together in any one mine on land.

As the metals can be harvested without too much difficulty, the energy consumption of the mining, waste production and the disturbance of the environment are minimal. Moreover, deep-sea mining, although it does not yet exist today, is already very strictly regulated. The CCZ falls under the powers of the International Seabed Authority (ISA), which regulates international waters under the flag of the United Nations. The ISA will soon impose very strict standards on any operators looking to begin mining the deep sea bed for minerals. These are intended to guarantee that the deep-sea marine environment and biodiversity are protected by designating protect areas where no mining will be permitted. In addition, the royalties from deep-sea mining must be fairly distributed among humanity, with an emphasis on developing countries.

The emergence of deep-sea mining is part of a global, even planetary, approach to use the earth’s natural resources in the most responsible way for the transition to a sustainable energy system. In this regard, land-based mining and deep-sea mining cannot be seen in isolation from each other.

Kris Van Nijen, Managing Director at Global Sea Mineral Resources