Geological Resource Planetary Boundaries: Exploring the Limits of Regional Water Available

Geological resources such as metals and minerals are essential for the spread of technologies such as renewable energy and energy storage in a decarbonized society, are essential to supporting modern life in the form of a variety of products and services. Their demand is expected to increase over the next few years due to the global population and economic growth.

So far, scientists and policymakers have primarily discussed the availability of geological resources in terms of ecosphere and technology reserves and resources. However, resources such as metals require a large amount of energy and water resources for various production processes such as mining, beneficiaries, and refining, which can constrain production. Therefore, there is concern as to whether production of geological resources can continue within sustainable use restrictions on water availability (planetary boundaries) or whether production can be increased to meet future increases in demand.

In addition to carbon emissions related to geological resource production, which accounts for around 10% of the world’s carbon emissions, water consumption is another major environmental concern. Surprisingly, water consumption in resource production has already surpassed sustainable levels in many regions, with 24% of the world’s water demand exceeding the capacity of available water resources. This situation could limit the availability of critical metals and minerals needed to advance green technology.

Despite the urgency, comprehensive global analysis of sustainable water use in geological resource production is limited.

In recent advancements, Japan, the National Institute of Advanced Industrial Science and Technology, an international team of researchers led by Masaharu Motoshita of the National Institute of Safety and Sustainability, has investigated the potential for water constraints for the availability of geological resources as planetary boundaries for geological resource production.

This study has been published in Journal Science.

“Previous studies have demonstrated that major basin colonels, who make up 80% of total water consumption, face water overdose beyond their load capacity,” Dr. Mototheta said.

In this new study, the team estimated water consumption associated with the production of 32 major geological resources in around 3,300 mines around the world. The results revealed that water use in the production of 25 of these resources exceeds the sustainable limits of water availability.

In particular, iron production is high water consumption, but in 2010 only 9% of production exceeded water constraints. In contrast, copper production exceeded sustainable water restrictions, despite low water consumption, 37% of current production exceeded sustainable water restrictions. This underscores the need for sustainable water use in geological resource production, particularly water-intensive metals such as copper.

This study emphasizes that constraints on resource production are determined not only by the total amount of water consumed, but also by the availability of local water. Shifting production to areas with low water stress could reduce some of these pressures. However, in many cases, logistics, economic, infrastructure challenges, and the geology of where resources are located makes it impossible to move production operations into the region with abundant water.

“The findings from this project will help predict potential disruptions in the supply of metals and other materials that are critical to modern green technologies, such as renewable energy and energy storage,” says Dr. Motoshita.

“Improve resource efficiency, improve recyclability, and explore alternative resources to address future supply challenges. Furthermore, these insights will guide policy decisions on resource exploration and sourcing, alternative materials selection, and development of sustainability goals for the use and recycling of geological resources.”

This study highlights the need to consider more comprehensively environmental constraints in future production of geological resources. With increasing demand and increasing environmental pressures, understanding and managing the environmental impact of geological resource production is important to achieving long-term sustainability and achieving global goals of clean energy and decarbonization.