A new study explores the environmental, social, and economic costs of different sources of base metals used in the world’s transition away from fossil fuels. The white paper is entitled Where Should Metals for the Green Transition Come From? The research considers the age-old question of land vs. ocean, in this case with regards to where mining for EV battery metals should take place.
The study, which was commissioned by deep-sea mining company DeepGreen, uses a “lifecycle sustainability analysis” and “standard lifecycle analysis” framework that provides an in-depth comparison of the cradle-to-gate impacts of producing metals from land ores and polymetallic nodules, both sources of the nickel, cobalt, copper, and manganese required to build one billion EV batteries. Regarding polymetallic nodules, DeepGreen Chairman and CEO Gerard Barron said, “they’re effectively an EV battery in a rock.”
A press release regarding the study notes, “The researchers examine the relative impacts of the extraction, processing and refining of these key base metals on several impact categories, including: greenhouse gas emissions and carbon sequestration, ecosystem services, non-living resources and habitats, biodiversity, human health and economics.”
One of the white paper’s lead researchers, marine biologist and ecologist Dr. Steven Katona, said of the findings: “Over the last 5 years there has been heightened awareness of the environmental, social and economic impacts of producing metals from land ores. We essentially built on existing lifecycle assessment indicators work for land-based mining and created an apples-to-apples comparison for battery material production from ocean nodules.”
The main conclusion: getting the metals from ocean nodules would be better. There is less net cost for society, including the environment we rely on, mining metals from the ocean — according to these researchers.
More specific findings are that obtaining the metals from the ocean result in:
- 70% less CO2e direct emissions
- 94% less stored carbon at risk
- 90% reduction in SOx and NOx emissions
- 100% reduction in solid waste
- 94% less land use
- 93% less wildlife at risk
The press release notes, “While the deep seabed is a food-poor environment with limited biomass, uncertainties remain over the nature as well as temporal and spatial scales of impacts from nodule collection on deep-sea wildlife. The study provides the broader context for a deeper, multi-year environmental and social impact assessment (ESIA) being conducted by DeepGreen, in what the company says will be the largest integrated seabed-to-surface deep-ocean science program ever conducted, with over 100 separate studies being undertaken. DeepGreen has partnered with three pacific island states for deep-sea environmental studies, mineral exploration and project development. Through these relationships with the Republic of Nauru, the Republic of Kiribati and the Kingdom of Tonga, DeepGreen has exclusive rights under the International Seabed Authority to explore for polymetallic nodules in regions of the Clarion Clipperton Zone of the Pacific Ocean. “
DeepGreen’s Exploration Vessel
“Ocean nodules are a unique resource to consider at a time when society urgently needs a good solution for supplying new virgin metals for the green transition. Extraction of virgin metals — from any source — is by definition not sustainable and generates environmental damage. It’s our responsibility to understand the benefits — as well as the damages associated with sourcing base metals from nodules,” Barron adds.
“Polymetallic nodules sitting on top of the seabed can be collected without drilling or having to move rocks or dirt. They are made of almost 100% usable minerals, compared to ores mined from the land which have increasingly low yields (often below 1%),” DeepGreen adds.
“This means that nodule collection has 99% less solid waste compared to land-based mining, and generates no toxic tailings.”
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.”
Important metals for the cleantech transition that are found in these nodules include cobalt, nickel, copper, and manganese.
DeepGreen continues to engender hope of safety, “We plan to lift them to the surface, take them to shore and process them with near-zero solid waste and no tailings; no deforestation, and with careful attention not to harm the integrity of the deep ocean ecosystem.”
DeepGreen aims to have the world generate at least 75% less CO2 using these nodules for EV battery metals than we would create using ores from land-based mines.
That would also mean not taking advantage of indigenous peoples, enrolling child labor, and better safety regulations in the sector.