Do we have enough minerals on Earth to move away from fossil fuels?
The transition to a fully electrified energy system requires mineral resources for batteries, electric motors, transmission lines, solar panels, wind turbines, etc. In this post, we'll examine the volume of materials needed and compare this to what we already have on hand.
When the lifespan of these devices is complete, these minerals can be recycled to create a sustainable, closed-loop system. This is unlike fossil fuel use, which demands a continuous fuel supply; with no end to mining and drilling until the planet is desiccated. Electrification leverages finite mineral reserves that can be reused extensively, offering flexibility and resilience. This is "Electrify Everything, Recycle Endlessly" vision of a sustainable energy future. So let's look at what's required and see if it's possible to get there.
Minerals in Electrified Energy Systems
Batteries
Batteries are central to electrification, powering electric vehicles (EVs) and storing renewable energy. Lithium-ion batteries (depending on the type) rely on lithium, cobalt, nickel, manganese, and graphite. Emerging chemistries, such as lithium iron phosphate (LFP), reduce dependence on cobalt and nickel, using more abundant materials like iron and phosphorus.
Electric Motors
There are seven broad categories of motors (DC, AC Synchronous, AC Induction, Switched Reluctance Motor, Stepper, Universal, Specialty). These broad categories can be further subdivided into 12 to 15 species (depending on your criteria). Not all motor types are suited for any given use case, but there's a lot of overlap in where and how they can be utilized and the materials that comprise them.
Electric motors, particularly those in EVs and wind turbines, often use neodymium and dysprosium for powerful magnets, though alternatives like ferrite magnets are being explored to reduce reliance on scarce materials. Electric motors can be made completely without rare earth materials and even without magnets. For example, the Switched Reluctance Motor (SRM) uses coils of a ferromagnetic material like iron to create a magnetic field in the stator. The rotor coils align with the magnetic field to minimize reluctance, producing motion. Since the rotor is simply iron (or similar materials) and the stator uses copper windings, no permanent magnets or rare earth materials are required.
Another example is the induction motor, which can be designed without permanent magnets. In a squirrel-cage induction motor, the rotor consists of conductive bars (often aluminum or copper) shorted together, and the rotating magnetic field from the stator induces currents in the rotor, creating torque. While some induction motors may use magnetic materials for efficiency, the basic design doesn't rely on rare earths or permanent magnets.
Both types are widely used in industrial applications and are valued for their simplicity, robustness, and lower reliance on costly or scarce materials. However, they may have trade-offs like lower power density or efficiency compared to permanent magnet motors in some applications.
Transmission Lines
Transmission lines are critical for delivering energy. They primarily use aluminum for conductors, such as Aluminum Conductor Steel Reinforced (ACSR), All-Aluminum Alloy Conductor (AAAC), or Aluminum Conductor Alloy Reinforced (ACAR), due to its conductivity and low weight. ACSR often has a steel core for strength. Copper is rarely used due to cost. However, if aluminum is scarce or the price increases significantly, copper or Aluminum Conductor Composite Core (ACCC) with a carbon fiber core can substitute.
Solar Panels
Solar panels use highly abundant silicon for photovoltaic cells. Silver, tellurium, and indium are used for specific designs like thin-film panels.
Wind Turbines
We've already covered the electric motor portion, so now we'll look at the rest of the turbine. Wind turbines primarily use steel for structural components. These materials are finite but highly recyclable.
Round & Round We Go
Good Batteries Become Great Batteries
Recycling is a cornerstone of the electrified energy system. As JB Straubel, founder of Redwood Materials, noted, over 99% of battery metals such as lithium, cobalt, and nickel can be reused without degradation. Recycled materials often outperform newly mined materials since the repeated refining cycles enhance their purity.
This high recyclability contrasts sharply with fossil fuels, where coal, oil, and methane that are burned, dumped into the atmosphere, and lost forever. Recycling programs for batteries, solar panels, and wind turbine components are expanding, reducing the need for virgin materials and mitigating environmental impacts from mining.
Additionally, by the time a battery is recycled for materials, the underlying technology has usually advanced, and new batteries often need less material for the same storage value. For example, the material from 100 five-year-old cells could make 120 new cells today.
Avoid the Fossil Fuel Lock-In
Fossil fuels lock societies into rigid systems. A petrol engine requires petrol, and a diesel engine demands diesel, with little-to-no flexibility to adapt to price surges or supply disruptions. Coal plants are similarly tethered to coal supplies. Continuous mining and drilling are necessary to sustain these systems, leading to environmental degradation and geopolitical dependencies. For example, oil extraction involves ongoing drilling, often in ecologically sensitive areas, while coal mining scars landscapes and emits significant greenhouse gases even before the coal itself is burned.
In contrast, electrified systems offer flexibility. Battery chemistries are diverse, ranging from lithium-ion to sodium-ion, solid-state, or flow batteries. If cobalt prices surge, manufacturers can pivot to LFP or other low-cobalt options. Similarly, electric motors can be made in many ways, with many different materials.
And even renewable energy generation itself is versatile. If solar panel costs rise due to silicon or silver shortages, wind, hydroelectric, or geothermal energy can fill the gap. Market dynamics drive innovation, ensuring that price spikes in one material or technology spur alternatives, fostering a resilient energy ecosystem, rather than a system tethered to a single volatile fuel source.
Challenges and Opportunities
The transition to a fully electrified society requires significant mineral production increases for materials like neodymium, dysprosium, tellurium, and solar-grade polysilicon, as highlighted in a 2023 Joule* study. While geological reserves are sufficient, scaling mining sustainably is critical to avoid environmental damage. Recycling mitigates this by reducing demand for primary sources. For instance, recycled copper from transmission lines and battery components can meet a significant portion of future needs, especially as EV adoption grows and end-of-life batteries become available.
The environmental footprint of mineral extraction, though notable, is a small fraction of fossil fuel emissions. The Joule study estimates that material-related emissions for a 1.5°C scenario (4-29 Gt CO2eq) consume only 1-9% of the carbon budget, far less than the ongoing emissions from burning fossil fuels. Innovations in low-carbon mining and processing, coupled with recycling, further shrink this footprint, aligning with the goal of a "Future Free from Fossil Fuels."
Mineral Requirements and Alternatives
The table below summarizes key elements for electrification, estimated needs for a 100% electrified society by 2050, current mined quantities, global reserves, and alternatives, based on studies like the one from Joule and industry insights.
| Element | Estimated Need (Mt, 2020-2050) | Already Mined/In Use (Mt) | Estimated Global Reserves (Mt) | Alternatives |
|---|---|---|---|---|
| Lithium | 0.5-1.5 | 0.1 | 22 | Sodium, magnesium-based batteries |
| Cobalt | 0.3-0.8 | 0.14 | 7.6 | LFP batteries, nickel-heavy chemistries |
| Nickel | 3.8 | 2.7 | 95 | LFP, iron-based batteries |
| Copper | 81.8 | 26 | 880 | Aluminum, recycled copper |
| Aluminum | 241 | 68 | 30,000 (30Gt) | Recycled aluminum, steel |
| Neodymium | 0.9 - 1.0 | 0.02 | 12.8 | Ferrite magnets, other rare earths |
| Dysprosium | 0.08 - 0.09 | 0.002 | 1.1 | Ferrite magnets, copper induction magnet |
| Tellurium | 0.042 | 0.0006 | 0.031 | Silicon-based PV, CIGS thin-film |
| Silver | 0.068 | 0.025 | 0.64 | Aluminum, copper in PV |
| Silicon (Polysilicon) | 22.5 | 0.75 | N/A (abundant) | Thin-film technologies |
| Steel (Iron and Carbon) | 1,960 | 1,870 | N/A (abundant) | Recycled steel, aluminum |
Notes: Needs are cumulative for 2020-2050 in 1.5°C scenarios (Joule, 2023). "Already Mined/In Use" reflects annual production as a proxy for in-use stock. Reserves are from USGS and other sources. Alternatives include substitutes and recycling.
Conclusion
The mantra "Electrify Everything, Recycle Endlessly" encapsulates the path to a sustainable energy future. Minerals for batteries, motors, transmission lines, and renewables are finite but recyclable (closed-loop), offering a stark contrast to the perpetual extraction demanded by fossil fuels (open-loop). The flexibility of battery chemistries and renewable energy sources ensures resilience against supply constraints, unlike the rigid lock-in of fossil fuel systems. By prioritizing recycling and innovation, we can secure the minerals needed for a "Future Free from Fossil Fuels," minimizing environmental impacts and ensuring a sustainable, electrified world.
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