Consider the costs of the green transition to the planet and people.

We make our world by extracting almost a hundred billion tons of resources from the planet every year. Through our relentless resource consumption, we have changed the land, oceans and atmosphere to a point where the future livability of our planet is in question.

In addition to population growth and rising living standards, we are now faced with a new, urgent and resource-intensive need — transitioning our entire energy, transportation and industrial infrastructure away from fossil fuels. We need to build tens of thousands of solar and wind farms, terawatts of energy storage capacity, billions of electric car batteries. This green transition will require an injection of hundreds of millions of tonnes of metal. Where will this metal come from and at what cost to the planet and its people?

Together with independent researchers, we have produced an in-depth lifecycle assessment study that compares the cradle-to-gate impacts of two sources of metals – land ores and deep-sea polymetallic metals. The study focuses on four metals used in manufacturing EV battery cathodes and wiring: nickel, cobalt, manganese and copper.

If the goal is to minimize further damage to the planet and produce the world’s greenest, most ethical electric vehicles, where should EV manufacturers source their base metals? This is the central question motivating the study. You can download it here. You can download it here.

Imagine a billion electric cars

An electric vehicle with a 75KWh battery and NMC 811 (nickel-manganese-cobalt) chemistry needs 56 kg of nickel, 7 kg of manganese, 7 kg of cobalt and 85 kg of copper for electric wiring. About 1.3 billion light passenger cars drive on this planet today emitting planet-heating CO2 and air-polluting NOx and SOx. Imagine we improve the world’s public transport, increase the use of ride-hailing services (and one day robotaxi fleets) and manage to keep the global car fleet size down to 1 billion cars despite adding another three billion people by the end of this century. If we replaced 1 billion gas-guzzling cars with electric cars, we would need 85 million tonnes of copper (21Mt mined in 2019), 56 million tonnes of Ni (2.3Mt mined in 2019,  only 50% suitable for batteries), 7 million tonnes of manganese (18Mt mined in 2019) and 7 million tonnes of cobalt (140Kt mined in 2019).

Explore two alternative sources of metals

Polymetallic nodules are made of almost 100% usable minerals and contain no toxic levels of deleterious elements, compared to ores mined from the land which have increasingly low yields (often below 1%) and often do contain toxic levels of deleterious elements. This means that producing metals from nodules has the potential to generate almost zero solid waste and no toxic tailings, as opposed to terrestrial mining processes which produce billions of tonnes of waste and can leak deadly toxins into soil and water resources.

Compare the impacts


Most of us have learned to read the small print of nutrition labels to make better food choices in the name of our health. We now need to learn to carefully examine the impacts of our resource extraction to make better choices in the name of planetary health (which eventually boomerangs as our own health and long-term prospects on this planet). The bad news is, the extraction of non-renewable metal-bearing mineral resources is by definition not sustainable and cannot be done without damage. The good news is, metals are recyclable and over time, as we build up enough metal stock-in-use to cover our needs, we should be able to cycle and recycle the same stock through the system. In the meantime, where should the missing stock of metals come from? There is no perfect option but there may be a better option.